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Best Practice industrial refrigeration part
18.01.2013 Version 1.1 1/131
BEST PRACTICE Industrial refrigeration sections
This document is the property of Carrefour and may not be copied or modified without prior permission.
Contents
1 GENERAL ............................................................................................................... 7
1.1 BEST PRACTICE, INDUSTRIAL REFRIGERATION SECTIONS ..................... 7
1.2 DOCUMENTS TO BE APPLIED ....................................................................... 7
1.3 FOREWORD ..................................................................................................... 7
1.4 DEFINITION OF THE SERVICES TO BE PROVIDED ................................... 10
1.5 TECHNICAL DOCUMENTS ............................................................................ 10
1.5.1 TECHNICAL DOCUMENTS ..................................................................... 10
1.5.2 OVERALL POWERS AND FLOW-RATES ............................................... 11
1.6 LEGISLATIONS .............................................................................................. 11
2 CALCULATION BASES ......................................................................................... 11
2.1 BASIC OUTDOOR CONDITIONS................................................................... 11
2.2 BASIC INDOOR CONDITIONS ...................................................................... 11
2.3 PERFORMANCE OBLIGATION ..................................................................... 11
2.4 THERMAL REQUIREMENTS ......................................................................... 12
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2.4.1 COLD ROOMS ......................................................................................... 12
2.4.2 REFRIGERATED SALES FIXTURES ...................................................... 13
3 REFRIGERATION OUTPUT ................................................................................. 15
3.1 CHARACTERISTICS AND GENERAL PRINCIPLE ........................................ 15
3.2 CENTRALIZED LOCATION ............................................................................ 16
3.3.1 REFRIGERATION MACHINES AND ACCESSORIES ............................. 17
3.3.2 REFRIGERATED DISPLAY CABINETS .................................................. 20
3.4 OPERATING RATES AND POWERS ............................................................. 30
3.4.1 BOOSTER CONFIGURATION AND RATES ............................................ 30
3.4.2 LABORATORY OR WORKROOM ........................................................... 32
3.4.3 EXCHANGER FOR FLASHGAS SUPER-HEATING ................................ 33
3.4.4 EXCHANGER FOR LIQUID SUBCOOLING............................................. 34
3.4.5 DE-SUPERHEATER, FREEZER INSTALLATION ................................... 35
3.4.6 GAS COOLER RATES AND CONFIGURATION ..................................... 36
3.5 DESCRIPTION OF THE EQUIPMENT ........................................................... 43
3.5.1 REFRIGERATION, BOOSTER ................................................................. 43
3.6 GAS COOLER ................................................................................................ 51
3.7 FREEZER DE-SUPERHEATER ..................................................................... 53
4 INDUSTRIAL REFRIGERATION SECTION REFRIGERATED UNITS ................. 54
4.1 CHILLER AND FREEZER FIXTURES ............................................................ 54
5 R744 REFRIGERATION INSULATION AND PIPING ........................................... 63
5.1 TECHNICAL SPECIFICATIONS AND GENERAL POINTS, PIPING .............. 63
5.3 DESCRIPTION OF REFRIGERATION PIPING/FITTINGS AND INSULATION .............................................................................................................................. 72
5.3.1 SUCTION AND DISCHARGE LINE .......................................................... 72
6 SAFETY ................................................................................................................. 73
6.1 PLANT ROOM CO2 DETECTION ................................................................... 73
6.1.1 EQUIPMENT DESCRIPTION ................................................................... 73
6.2 CO2 DETECTION FOR COLD ROOMS, FREEZER ROOMS, SALES AREA, AND ADJOINING ROOMS ................................................................................... 74
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6.3 FREEZER ROOM TRAPPED PERSON ALARM ............................................ 75
6.4 SECTION SAFETY AND CUT-OFF VALVES ................................................. 76
6.5 COMPRESSORS ............................................................................................ 77
6.6 PLANT ROOM AIR EXTRACT VENTILATION ............................................... 78
6.7 EMERGENCY COOLING (OPTION) .............................................................. 80
6.8 EMERGENCY STOP AS PER EN 378 ........................................................... 82
6.9 PLANT ROOM ................................................................................................ 82
7 HEAT RECOVERY ................................................................................................ 83
7.1 DEFINITION OF TERMS ................................................................................ 83
7.2 DECISION BASIS FOR DHW HEAT RECOVERY .......................................... 83
7.3 GENERAL ....................................................................................................... 85
7.4 DOMESTIC HOT WATER ............................................................................... 86
7.5 HEATING HOT WATER .................................................................................. 87
7.6 EQUIPMENT DESCRIPTION ......................................................................... 88
7.6.1 DOMESTIC HOT WATER ........................................................................ 88
7.7 REGULATING DESCRIPTION ....................................................................... 90
7.7.1 HEAT RECOVERY, DOMESTIC HOT WATER ........................................ 90
8 REGULATION DESCRIPTION .............................................................................. 92
8.1 REFRIGERATION OUTPUT CO2 BOOSTER ................................................. 92
8.1.1 NORMAL AUTOMATIC OPERATION ...................................................... 92
8.1.2 MANUAL OR DEGRADED OPERATION ................................................. 92
8.1.3 REGULATION OF THE TRANSCRITICAL HIGH PRESSURE ................ 93
8.1.4 GAS COOLER REGULATION.................................................................. 94
8.2 REFRIGERATION UNITS ............................................................................... 95
8.2.1 REGULATION OF CHILLER AND FREEZER REFRIGERATION UNITS 95
8.3 LIGHTING CONTROL ..................................................................................... 97
8.3.1 NIGHT BLIND CONTROL: ....................................................................... 98
8.3.2 NIGHT OFFSET: ...................................................................................... 98
8.3.3 DEFROSTING REGULATION: ................................................................. 98
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8.3.4 EVAPORATION PRESSURE REGULATION ........................................... 98
8.3.5 DEW-POINT REGULATION ..................................................................... 98
8.3.6 CHILLER AND FREEZER ROOM DOOR CONTACTS ............................ 99
8.3.7 FREEZER ROOM AIR CURTAIN ............................................................. 99
8.3.8 FREEZER ROOM FAN STOPPING ......................................................... 99
8.3.9 TEMPERATURE DISPLAY ...................................................................... 99
9 CENTRAL ELECTRICAL DISTRIBUTION CABINETS AND REFRIGERATION UNITS ..................................................................................................................... 100
9.1 GENERAL AND EQUIPMENT ..................................................................... 100
9.1.1 CHILLER AND FREEZER REFRIGERATED UNIT POWER OUTPUTS ........................................................................................................................ 105
9.1.2 EQUIPMENT ......................................................................................... 106
10. REMOTE MONITORING ................................................................................. 111
10.1 GENERAL .................................................................................................. 111
10.2 DIAGRAM OF REMOTE DATA MONITORING ......................................... 112
11. TREATMENT OF ALARMS ............................................................................. 113
11.1 TECHNICAL ALARMS ............................................................................... 113
11.2 MANAGEMENT OF ALARMS .................................................................... 114
11.3 ACTION PROCEDURE – RESPONSE TO ALARMS ................................ 115
11.4 EMS SYSTEM INTERFACES .................................................................... 116
12. INSTALLATION ACCEPTANCE CONDITIONS .............................................. 116
12.1 PRIOR INSPECTION ................................................................................. 116
12.2 MOISTURE – VACUUM EVACUATION – LEAK-TIGHTNESS TEST* ...... 117
12.3 COMMISSIONING ..................................................................................... 118
12.3.1 GENERAL ........................................................................................... 118
12.3.2 PRIOR TO COMMISSIONING ............................................................ 118
12.3.3 PREPARATION FOR COMMISSIONING............................................ 118
12.3.4 COMMISSIONING ............................................................................... 118
12.3.5 COMMISSIONING HEAT RECOVERY FOR SANITARY HOT WATER ........................................................................................................................ 119
12.3.6 FULL TRAINING FOR STORE STAFF ............................................... 119
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12.3.7 DRAFTING THE COMMISSIONING REPORT ................................... 120
12.3.8 AFTER COMMISSIONING .................................................................. 120
12.3.9 PROVISION OF FINAL DOCUMENTS ............................................... 120
12.3.10 CHECKING REMOTE TRANSMISSION OF ALARMS ..................... 120
12.3.11 MARKING .......................................................................................... 121
12.4 DOCUMENTATION* .................................................................................. 121
12.4.1 AS BUILT FILE .................................................................................... 121
12.4.2 MISCELLANEOUS DOCUMENTS ...................................................... 123
12.5 MARKING DESIGN .................................................................................... 123
12.5.1 GENERAL ............................................................................................ 123
12.5.2 DESCRIPTION OF ELECTRICAL CONTROL CABINETS ................... 124
12.5.3 DESCRIPTION OF REFRIGERATION INSTALLATION ...................... 124
12.5.3.1 Conduits ........................................................................................... 124
12.5.3.2 Installation/Refrigerant agent ............................................................ 125
12.5.3.3 Compressor ....................................................................................... 125
12.5.3.4 All components requiring electrical connection .................................. 125
12.5.3.5 Refrigeration chiller/freezer cabinets ................................................. 126
12.5.3.6 Adhesive label for defrosts ................................................................ 126
12.5.4 SANITARY INSTALLATION DESCRIPTION ........................................ 126
12.5.5 HEATING DESCRIPTION .................................................................... 126
13. WARRANTY ..................................................................................................... 127
14. SERVICES NOT INCLUDED IN THE WORK PACKAGE / SCOPE OF SERVICES ............................................................................................................. 127
14.1 SCOPE OF SERVICES .............................................................................. 127
14.1.1 WORKS INCLUDED IN THE FOOD PRODUCTS REFRIGERATION WORK PACKAGE ........................................................................................... 127
14.1.2 WORKS EXCLUDED FROM THE FOOD PRODUCTS REFRIGERATION WORK PACKAGE ............................................................. 129
14.2 STRUCTURAL WORK PACKAGE .............................................................. 129
14.2.1 WORKS EXCLUDED FROM THE FOOD PRODUCTS REFRIGERATION WORK PACKAGE ............................................................. 129
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14.2.2 WORKS REQUIRED BY THE FOOD PRODUCTS REFRIGERATION WORK PACKAGE ........................................................................................... 129
14.3 WATER-TIGHTNESS – ROOF COVERING WORK PACKAGE ................. 129
14.3.1 WORKS EXCLUDED FROM THE FOOD PRODUCTS REFRIGERATION WORK PACKAGE ............................................................. 129
14.3.2 WORKS REQUIRED BY THE FOOD PRODUCTS REFRIGERATION WORK PACKAGE ........................................................................................... 129
14.3.3 WORKS REQUIRED BY THE FOOD PRODUCTS REFRIGERATION WORK PACKAGE ........................................................................................... 129
14.4 PARTITIONS – PAINTING – FALSE CEILINGS WORK PACKAGE .......... 129
14.4.1 WORKS REQUIRED BY THE FOOD PRODUCTS REFRIGERATION WORK PACKAGE ........................................................................................... 130
14.5 PLUMBING – SANITARY FACILITIES WORK PACKAGE ......................... 130
14.5.1 WORKS EXCLUDED FROM THE FOOD PRODUCTS REFRIGERATION WORK PACKAGE ............................................................. 130
14.5.2 WORKS REQUIRED BY THE FOOD PRODUCTS REFRIGERATION WORK PACKAGE ........................................................................................... 130
14.6 ELECTRICITY – HIGH-VOLTAGE .............................................................. 130
14.6.1 WORKS EXCLUDED FROM THE FOOD PRODUCTS REFRIGERATION WORK PACKAGE ............................................................. 130
14.6.2 WORKS REQUIRED BY THE FOOD PRODUCTS REFRIGERATION WORK PACKAGE ........................................................................................... 130
14.7 MISCELLANEOUS ...................................................................................... 130
14.7.1 CONDUCT – SUPERVISION – MAINTENANCE UNTIL ACCEPTANCE ........................................................................................................................ 130
14.7.2 TRAINING OPERATIONAL STAFF AND PROVIDING AS BUILT FILE130
14.7.3 REFRIGERANT FLUIDS ...................................................................... 131
14.7.4 PRESSURISED EQUIPMENT .............................................................. 131
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1 GENERAL
1.1 BEST PRACTICE, INDUSTRIAL REFRIGERATION SECTIONS By working on the basis of a standard within a circle of companies involved at a national and international level, we can develop standardization. Using this system, we obtain installations using current techniques produced in different places and by different people, all of them using identical working processes and techniques. Carrefour’s “Best Practice” is an internal standard used internationally. Putting these concepts into practice will, in the long term, lead to unified engineering with installations of high quality. Cost reduction will be the result of rationalizing resources. The contents of “best practice” documents are for information only and do not constitute a set of specifications. The manual takes account of external temperatures of +34 °C. If this value is different, appropriate measures must be examined separately.
1.2 DOCUMENTS TO BE APPLIED - Standards List document - Detail drawing no. 2597S2 - Detail drawing no. 2597S5 - Detail drawing no. 2597S6 - Outline diagram 2597S1 - Fitting instructions, industrial refrigeration section - Document: "Confirmation that the installation has been finished and is ready for acceptance" - Night blind (optional) - Heat recovery, domestic hot water and heating option - “SHEET industrial refrigeration section” - Best Practice for refrigerated units - Best Practice for cold rooms - Commercial refrigeration index - Framework contract for provision of comprehensive maintenance services for CO2 refrigeration installations. - Full service contract for CO2 refrigeration installations - CO2 installation maintenance operations sheets
1.3 FOREWORD Installations under the contract shall be carried out in accordance with the instructions and dimensions given in this best practice document drawn up by Carrefour as both project owner and project manager, and with the instructions common to all work packages; they shall comply with the set of plans in the dossier. As a general rule, the contract is assumed to include all work or rulings stipulated by the instigators of the project and works inspectors in ensuring the compliance of the work in accordance with the regulations in force for the work covered by the order. All deliveries and work must correspond with statutory requirements and with the requirements of the professional associations.
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In all cases, calculations must be based on the contents of the best practice documents appended and must include all those elements and capacities guaranteeing a suitable implementation and perfect operation of the installations. If the contractor has an alternative opinion in terms of the conditions, design, capacities, controls, or materials, or if they obtain different results, they shall state this in an ancillary document, stating their reasons explicitly. In the absence of written reservations or objections, it is assumed that the best practice document bases also correspond to the opinion of the contractor (refrigeration engineer). The contractor has an obligation to inform the project owner, at the latest at the contract award meetings, in order to agree any possible special conditions. In all cases, the agent shall assume entire responsibility for the installations as well as for their faultless operation. The tender shall include all the associated structures and services necessary for full and perfect completion of the work. The company must supply complete installations and parts in full working order; all work must be carried out in accordance with Best Professional Practice. If there are several possible interpretations of this text, the contractor has an obligation to inform the project owner of this in writing for them to clarify the situation. If they fail to do so, the project owner’s interpretation shall take precedence. If the contractor should wish to use materials or variants other than those indicated, they must make their request in a separate written document. The project owner reserves the right to split the contract award between several suppliers. The contractor will not be able to claim any compensation in the event of partial or total abandonment of certain positions during execution. The contractor shall remove all transport and packing materials from the site at their own expense. Unloading and fitting expenses (e.g. lifting plant) justified by the construction will be billed to the contractor. All prices shall be free at fitting location, with installation and adjustment, including associated works, even if these have not been expressly mentioned in the best practice documents or otherwise, but constitute part of the work required for faultless fitting.
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Any modifications to the order by increasing or eliminating certain work may only be carried out with the agreement of the project owner. No claims will be accepted without written confirmation from the project owner or by a corrective order. All additions or modifications to the original delivery volume will take place under the same conditions as for the principal mandate, as set down in the contractor contract. In principle, under a “cost plus” basis, working time is not remunerated, other than under a formal order from the project owner. Reports must be presented for signing within two days of the order. No “cost plus” reports will be accepted if not duly signed. The warranty starts to run as soon as all defects noted during acceptance have been eliminated. Any defects noted during the warranty period must be repaired at the contractor’s expense (including indirect damage). If the latter is able to prove that they are not responsible for the damage, they will be released from their obligations. The project owner or their consulting engineers shall carry out new checks prior to expiry of the warranty. Any defects shall be rectified within the times laid down in writing, and the project owner shall be informed of the repair. All documents necessary for execution of the work, such as assembly and connection diagrams, installation diagrams, etc., must be submitted by the contractor. A detailed diagram shall be produced for each installation and all devices shall be marked according to their type; no legends or additional sheets will be accepted. The refrigeration diagram shall be submitted to the project owner prior to the start of assembly. Services provided by the project owner or their consulting engineers: - checking execution outline diagrams - technical spot checking of work - acceptance of the installations Acceptance conditions: After the official commissioning, it will be necessary to establish an electronic temperature control strip for each refrigerated object (e.g. Hamster or Escort). For meat and fruit & veg cold rooms, the measurements will be made with the help of thermoscriptes. The measurement points will be agreed in advance with the project owner or their engineers. The minimum measurement duration shall be 24 hours. A check strip for the ambient temperature and relative humidity of the air in the store shall also be presented in addition to the temperature measurement. Each check strip shall be attached to an A4 format sheet; the position, date, and duration of the measurement shall also be indicated on this. At the latest 2 months after the unit has been officially brought into service, and following establishment of the control strips, the unit will undergo acceptance with the project owner or their consulting refrigeration engineers and the project owner’s maintenance department. The contractor shall inform the consulting engineers 3 weeks before the planned date. Acceptance includes: - inspection of the equipment/supplies - temperature checks - checks of functions and powers
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Ten hours shall be set aside for acceptance of the refrigeration installations by the project owner or their engineers. If at that time any untoward issues are observed in the installation or in certain parts, the acceptance process will be interrupted and adjourned. Any additional costs incurred by this delay will be deducted from the contractor’s invoice. The refrigeration installer is responsible for the faultless operation of the refrigeration installations and is liable for any damage caused to merchandise by malfunctions due to their own fault, from commissioning up to reception. Sales staff shall receive all necessary instructions for correct handling of the installations no later than the acceptance date. By signing, the contractor accepts the best practice documents, which form an integral part of the order. The contractor likewise certifies that they have been informed of the nature and volume of the work and deliveries, as well as about local conditions. Within the operating documents, the exact locations of the probes must be shown on each of the diagrams for the refrigerated units (p4, p1, etc.). Using these documents, maintenance personnel must very quickly be able to locate the probes in the event of a breakdown.
1.4 DEFINITION OF THE SERVICES TO BE PROVIDED The work in this work package involves: Chiller and freezer refrigeration production Refrigeration distribution as far as the cold rooms and sales area refrigerated fixtures. Refrigeration pipework from the cold-room and laboratory evaporators Connecting up the sales area refrigerated fixtures Ventilation of the refrigeration plant room Cooling of the refrigeration plant room Connecting up the drains from the cold rooms, laboratories, and refrigerated display cabinets The electrical and regulating installations for the various food refrigeration systems Reports for the BMS, including connection bus Generally, the contractor will be required to supply all necessary work and supplies and to produce installations capable of meeting the requirements as expressed and detailed in this Best Practice document, under all conditions of safety and regularity, or in the graphical documents attached as an annexe.
1.5 TECHNICAL DOCUMENTS 1.5.1 TECHNICAL DOCUMENTS This best practice document is completed by a series of engineering diagrams and drawings: See list provided in Section 1.2 All graphical documents submitted to the contractor for execution of the work must be considered as a proposal that they should examine before submitting their bid. Hence under his duty to advise, the contractor will be required to point out to the project manager those provisions that do not seem to him consistent with the conservation of the installations or their intended use, or any failure to respect best professional practice.
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After on-site reconnaissance by the service provide and unless the client requests a modification, it is specified that the contractor's bid will remain a fixed sum, regardless of any changes to circuit routing that might prove necessary when finalizing the execution plans. 1.5.2 OVERALL POWERS AND FLOW-RATES The powers and flow-rates figuring in the tender documents are given for information only; this work package will be required to adapt the powers to the store configuration in accordance with the client’s requests.
1.6 LEGISLATIONS In general, national and local regulations, standards, and laws must be respected. Exceptions specific to each country, identified in relation to this best practice document, must be communicated immediately to the project owner. It is requested that counter-proposals be presented to the project owner. The best practice document is subordinate to the laws and regulations specific to each country. The contractor is responsible for satisfying all the laws specific to each country, regulations and standards in force. Best Practice has been prepared on the basis of various standards. The separate ‘fundamental standards’ folder gives an overview of the various standards, but the list is not definitive.
2 CALCULATION BASES
2.1 BASIC OUTDOOR CONDITIONS Target values Actual values
depending on country
Summer temperature +34 °C + ___ °C
Chiller refrigerant R744 (CO2)
Freezer refrigerant R744 (CO2)
The manual takes account of outdoor temperatures up to a maximum of +34 °C. If this value is exceeded, appropriate measures must be examined separately.
2.2 BASIC INDOOR CONDITIONS
Sales area Target values Actual values depending on country
Summer temperature +25 °C/60%HR + ___ °C / HR __ % (NC)
Winter temperature +25 °C/60%HR + ___ °C / HR __ % (NC)
Cold rooms: see refrigeration report sheets
2.3 PERFORMANCE OBLIGATION The description of the work and the objective to be attained for each work package are given in the best practice technical request documents for each work package. For requests specific to the project, minimum performance levels shall be proposed by the service-provider and validated by the project owner. In the event of technical inconsistency or insufficiency, or simply to complement the services described, contractors will be required to propose in their bid techniques and products of their choosing, if necessary replacing the planned stipulations, in order to arrive at the description given and the objective to be attained.
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2.4 THERMAL REQUIREMENTS 2.4.1 COLD ROOMS 2.4.1.1 POWER Calculation basis for determining cold room powers: Depending on the country's legislation
Product type Stored product
temperature
Air relative humidity
Temperature of products when added
Specific heat capacity of products
Daily addition rate
Guide power per m²
PRE-PACKED MEAT
−1/+1 °C RH 80% 7 °C 3.349 kJ/kg*K 50 kg/m² 0.20 kW/m²
PRE-PACKED POULTRY
−1/+1 °C RH 80% 7 °C 3.349 kJ/kg*K 50 kg/m² 0.20 kW/m²
CARCASSES −1/+1 °C RH 90% 3 °C 3.141 kJ/kg*K 100 kg/m² 0.20 kW/m²
PRE-PACKED DELI MEATS
+1/+3 °C RH 80% 7 °C 3.349 kJ/kg*K 60 kg/m² 0.20 kW/m²
PREPARED DISHES
+1/+3 °C RH 85% 3 °C 3.141 kJ/kg*K 75 kg/m² 0.20 kW/m²
TROLLEYS PREPARED DISHES
−1/+1 °C RH 80% 3 °C 3.559 kJ/kg*K 75 kg/m² 0.20 kW/m²
FRESH CAKES & PASTRIES
0/+2 °C RH 80% 7 °C 2.931 kJ/kg*K 50 kg/m² 0.20 kW/m²
FISH ON ICE −1/+1 °C RH 90% 4 °C 3.349 kJ/kg*K 75 kg/m2² 0.20 kW/m²
FRUITS & VEGETABLES
+6/+8 °C RH 90% 16 °C 3.768 kJ/kg*K 100 kg/m² 0.25 kW/m²
PACKAGED DAIRY/EGGS
+3/+5 °C RH 80% 4 °C 2.722 kJ/kg*K 100 kg/m² 0.20 kW/m²
CHEESE +3/+5 °C RH 85% 6 °C 2.931 kJ/kg*K 70 kg/m² 0.20 kW/m²
FISH −1/+1 °C RH 75% 2 °C 3.768 kJ/kg*K 100 kg/m² 0.20 kW/m²
FOOD WASTE +3/+5 °C RH 75% 10 °C 3.349 kJ/kg*K 80 kg/m² 0.20 kW/m²
FROZEN PRODUCTS
−25 °C RH 90% −18 °C 1.759 kJ/kg*K 90 kg/m² 0.22 kW/m²
ICE-CREAMS −25 °C RH 90% -18 °C 1.885 kJ/kg*K 90 kg/m² 0.22 kW/m²
Given the frequency of deliveries, the refrigeration power shall be calculated with a loading factor of 25% of the total volume of the cold room. The values must be verified according to the country and specifically for each project
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Laboratory type Air temperature
Air relative humidity
Installed power Occupation
CUTTING +8/+10 °C RH 70% 0.06 kW/m² 0.1 person/m²
CUTTING / PACKING +8/+10 °C RH 70% 0.12 kW/m² 0.125 person/m²
PACKING / CUTTING / MARKING
+8/+10 °C RH 70% 0.30 kW/m² 0.167 person/m²
OPERATING TIMES:
Dairy cold rooms 12 hr
Fruit & veg cold rooms 14 hr
Meat cold rooms 14 hr
Fish cold room 14 hr
Miscellaneous cold rooms 14 hr
Freezer rooms 16 hr Insulation assumptions shall correspond to existing thermally-insulating barriers for existing cold rooms, and 6 W/m² (walls, ceiling, floor) for new cold rooms. The air renewal assumptions are specific to the volumes of the cold rooms. 2.4.1.2 THERMAL REQUIREMENTS Where there are no consulting engineers, calculation of the thermal requirements for cold rooms, laboratories, and other areas is the responsibility of the refrigeration work package. The total installed power, resulting from the thermal, furnishing, cold room and laboratory requirements, shall be used to determine the type of refrigeration unit. Chiller installation: Freezer installation:
2.4.2 REFRIGERATED SALES FIXTURES 2.4.2.1 POWER
reserve
+ 5% reserve
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100% Refrigeration power in negative refrigeration units
reserve
+ 5% reserve
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100% Refrigeration power in positive refrigeration units
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The refrigeration power and operating rate (evaporation temperature) are provided by the unit manufacturer. The contractor is responsible for the power calculations. The powers declared shall comply with the EN23953-2:2005 +A1:2012 standard or be in accordance with local legislation. Reminder: cold rooms and refrigerated sales fixtures are intended to keep products for sale at the correct temperature. 2.4.2.2 AMBIENT SURROUNDINGS CLASS The store is heated in winter and cooled in summer, but not in spring or autumn, or air-conditioned for part or all of the year in hot regions. The power of the refrigerated sales fixtures shall be calculated in Class 3.
Dry temperature +25 °C
Relative humidity 60% Depending on country references 2.4.2.3 THERMAL REQUIREMENT Where there are no consulting engineers, calculation of the thermal requirement for refrigerated display cabinets and other elements is the responsibility of the refrigeration work package. Nevertheless, the refrigeration work package service provider must check all the powers. The total installed power, resulting from the thermal, furnishing, cold room and laboratory requirements, shall be used to determine the type of refrigeration unit. Chiller installation: Freezer installation:
reserve
+ 5% reserve
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100% Refrigeration power in negative refrigeration units
reserve
+ 5% reserve
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3 REFRIGERATION OUTPUT
3.1 CHARACTERISTICS AND GENERAL PRINCIPLE Chiller and freezer refrigeration production shall be accomplished by one or more booster units or independent direct-expansion chiller installations, comprising an oil separator, oil regulation system, subcooler, two liquid separators, a liquid receiver, regulating valves, the machine electrical cabinet, all safety, control, and regulating devices (see outline diagram). It is incumbent on the installer to respect the appropriate standards, stipulations, and orders (e.g. OESP, EN 378: 2008). Refrigeration production for all chiller and freezer units, cold rooms, laboratories, and freezer rooms shall be provided using R744 refrigerant. The distribution of the cooling/freezing units between the different installation units must be such that refrigerated units with similar evaporation temperatures (e.g. higher) can be connected to the same refrigeration installation. This allows the refrigeration installation to be sized using a higher evaporation temperature.
Sales area
Positive compressors
Gas cooler
Negative compressors
Positive units
Negative units
Medium pressure regulator valve
Gas cooler/ condenser
High pressure regulator valve
Liquid sub-cooling
Expansio
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Liq
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3.2 CENTRALIZED LOCATION Depending on the configuration of the plant rooms (dimensions) or the store situation, several types of refrigeration plant are possible:
One-piece indoor unit with air gas cooler on roof. Large plant rooms with easy access. Priority variant, the best choice
Example for indoor installation in the form of a complete refrigeration unit
Conventional central refrigeration unit using multiplex and separated circuit piping and air gas cooler on roof. Confined spaces, town-centre stores, etc.
Possible example of a separate factory pre-wired central refrigeration unit with outdoor gas cooler
Outdoor one-piece air condensation unit (gas cooler). Located in yard, outside, or on roof. Combined booster installation comprising all components such as gas cooler, gas de-superheater, etc. Ready to install outdoors. It is necessary to ensure compliance with local orders concerning noise protection and access to the various services.
Example of an outdoor installation in the form of a complete refrigeration unit
Whatever type of unit is installed, outdoor or indoor, one-piece or split production, all of them shall be fitted in a similar way and shall group together all of the refrigeration and hydraulic equipment in accordance with the outline diagram enclosed and the data sheets. The weight of the central units must be communicated to the project manager in order to check the building structure.
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3.3 GENERAL AND TECHNICAL PRESCRIPTIONS
3.3.1 REFRIGERATION MACHINES AND ACCESSORIES Power-optimized, uninterrupted operation of the refrigeration installation must be ensured. As nothing is specified in terms of the types of compressor, these will be required to be of sound construction, in common use, and with a certain reputation on the market. Gas units and spare parts must be available in case of need within reasonable lead-times. Provision must be made for central refrigeration unit fanout factors (relationship between the refrigeration power of the refrigeration units and the refrigeration power provided by the compressors) as follows. Within this factor, the reserve power shall be included as per Sections 2.4.1 and 2.4.2 Chiller installation: Freezer installation:
Fanout factor for chiller installation depending on country _________% Fanout factor for freezer installation depending on country _________% The refrigeration installations must be designed in such a way as to avoid refrigerant or oil reaching the compressors directly and damaging them. If necessary, elements such as e.g. a liquid separator or a suction superheat exchanger will have to be used. The compressor supplier’s prescriptions must be adhered to. This concerns particularly the commissioning procedure, operating levels, and the type of oil recommended by the manufacturer. If necessary, provision must be made for casing heaters, oil coolers, or other necessary elements.
reserve
+ 5% reserve
Refr
ige
rati
on
po
we
r in
neg
ati
ve
refr
ige
rati
on
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its
100% Refrigeration power in negative refrigeration units
90% expansion factor
Ne
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po
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co
mp
res
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ma
xim
um
ou
tpu
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+ 5% reserve
100% Refrigeration power in positive refrigeration units
85% expansion factor
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refr
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The compressors must be fixed to the chassis in such a way that they do not generate excessive vibration, and by the same token do not cause breakage of the piping (risk of leaks) to the multiplex.
If several compressors are working in parallel on one system, each compressor must be separately fitted onto the multiplex system in such a way that it can be changed without interrupting operation of the system as a whole.
The refrigeration installer is responsible for complying with the prescriptions of the electricity company for starting and running the compressors. The necessary measurements shall be included in the price.
Compressors, gas units, and gas coolers shall be fitted on vibration dampers. Machine bases shall be isolated accordingly. The drawings of the bases, together with any vibration dampers, shall be prepared and supplied by the contractor.
Example of anti-vibration elements (Mafund pads)
All control and signalling instruments and devices shall be labelled.
The lubrication of the compressors using R744 must be performed in such a way as to ensure adequate oil viscosity. If necessary, air-cooled oil coolers must be used. Furthermore, compressor oil temperatures must be individually monitored and compressors taken out of circuit if the limit values are exceeded.
The R744 compressors must each have a low- and high-pressure safety valve. This may be fitted within or external to the compressor.
All armatures and suction adjustment devices must be insulated.
The filtration medium must be compatible with the refrigeration oil. Activated alumina may not be used as a filtration medium when polyester-based refrigeration oil with special additives is used.
The filters on the suction pipes of refrigeration installations running on R744 may include pores with a maximum size of 60 µm.
For seals with CO2, which under normal circumstances need to be replaced during the installation’s lifetime (e.g. filter housing seal), these must be provided for in one material (e.g. Ethylene-Propylene EPDM). Rubber (e.g. NBR, FKM) or fluoridated polymer (FP, proprietary name Viton) seals must not be used. In the event that this is not possible, the non-compliant seals must be changed when the circuit is decompressed.
Dryers must use only molecular sieve cores and be sized in such a way as to minimize the moisture level in the installation as far as possible.
Cores using activated alumina are prohibited.
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The liquid receiver must be sized so as to always have correct high and low levels under all conditions (heat recovery / summer / winter).
Provision must be made for at least 4 main safety valves, to be sized according to the standards: 1. HP valve (compressors) 2. MP valve (liquid receiver) 3. Chiller BP valve (evaporators) 4. Freezer BP valve (evaporators)
Sales area
The sizing of the safety valves along with the technical data must allow for all potential hazards (expansion, external fire, circuit partitioning).
In order to guarantee operation of the installation even in the event of a failure in the electronic pressure regulators, provision should be made for mechanical back-up regulators.
Refrigerant alarm: The level in the receiver must be monitored. If the liquid level in the receiver is indicated using a magnetic level indicator, the level indicated must show the actual level and must be able to be isolated from the receiver. The indicator’s lower connecting pipe must be connected to the lowest possible point on the receiver to avoid siphon effects.
Positive compressors
Gas cooler/ condenser
High pressure regulator valve
Medium pressure regulator valve
Liquid
sub-cooling Gas cooler
Negative compressors
Positive units
Negative units
Liq
uid
tan
k
Expansio
n
valv
es
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The level monitoring must include 3 alarm contacts as follows: High level alarm: Priority 1 signalling, closure of HP valve Low level alarm: Priority 2 signalling, max. delay time 20 min. Very low level alarm: Priority 1 signalling, max. delay time 5 min. Equipment used for the chiller and freezer circuits must be compatible with CO2 and have an operating pressure of:
Position Set-point Actual, depending on country
Chiller high pressure, minimum 110 bar dry gas cooler
____ bar
Chiller high pressure, minimum 110 bar water-cooled gas cooler
____ bar
Chiller medium pressure, minimum 42 bar ____ bar
Chiller low pressure, minimum 42 bar ____ bar
Freezer high pressure, minimum 42 bar ____ bar
Freezer low pressure, minimum 24 bar ____ bar
Care must be taken to ensure that the CO2 safety release valves do not present a hazard to personnel. Safety instruction information such as “handling CO2” and “handling cylinders of CO2” shall be legibly and prominently posted adjacent to the refrigeration installations. Safety valve opening pressures must be 2 bar higher than the pressure of the main valves. 3.3.2 REFRIGERATED DISPLAY CABINETS The cutting points as per drawing 2597S2 form part of the technical conditions Direct-evaporation chiller and freezer units using R744 must be regulated in such a way as to minimize the pressure increase in the suction pipe during a failure in the installation. Ventilations, expansion valves, and electric defrost heating must stop automatically when a fault appears and start up again once the fault has been corrected. If display cabinets are not in defrost mode, the evaporator fans and refrigeration power regulation shall run continuously, corresponding to a “Continuous” setting. Delivery ‘free to site’, positioning, and assembly of the refrigerated fixture elements form an integral part of the services to be provided by the supplier. Removal and refitting of the glazing and the provision of frames is the responsibility of the Works Management. Chiller and freezer display cabinets must be protected in exposed locations (passages etc.) using sturdy stainless pillars. Delivery and installation shall be carried out by the refrigeration contractor. The dimensions of a stainless protective pillar shall be L × Ø × thickness, 400 × 60.3 × 2 mm. This protective element is open at the bottom and top, fitted with a welded stainless cap as per attached drawing.
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The pillars shall be fitted to a depth of 100 mm into holes provided for this purpose. Fixing shall be performed using a 2-component adhesive as per the drawing. Hence the visible height of the protective pillars in the store will be 300 mm.
Example of protection for refrigerated units
Example of linear protection
Each chiller or freezer display module shall be fitted with a display giving temperature, defrost, and alarm information. Provision shall also be made for a switch to disable the refrigeration block in each unit.
The display must correspond to the actual temperature in the chiller and freezer cabinets.
All refrigerated sales units shall be fitted with a label indicating:
The number of defrost operations and timetable.
The regulated temperature for the unit.
This unit’s reference on the temperature recording system.
This label shall be positioned on the unit’s front panel adjacent to the display thermometer, as per current legislation.
For the type of defrosting for chiller and freezer cabinets, the following instructions shall be adhered to: Electric defrosting for chiller cabinets is not accepted. If the number of defrosting operations set during commissioning and the optimization phase are no longer enough, the causes must be found and eliminated. Six months after the refrigeration installation is commissioned, the number of defrost operations may be adapted specifically to each store. If units with glazed doors have to be fitted with electric heating elements, prior agreement from the project owner is necessary.
Depth of hole
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Type of display cabinet
Type of defrost Number of defrosts, depending on temperature within unit
Chiller cabinets fan-assisted Once, up to a max. of twice a day
Freezer cabinets electric Once a week, up to a max. of once a day
Defrosting operations must take place as far as possible outside store opening hours and shall be kept to a strict minimum. During the defrost cycles, the temperature of the frozen products @ 1 cm below the surface shall not exceed the following values: - Ice-cream −18 °C - Frozen products −15 °C Heating of frame and glazing: For chiller cabinets, no provision is to be made for heating the frame and glazing. For freezer cabinets, no provision is to be made for heating the glazing (Antifog surface treatment). Frame heating for freezer cabinets shall be controlled in accordance with the heat capacity of the store. Satellite distribution boards for chiller and freezer cabinets: A satellite dis. board must be positioned adjacent to each refrigerated unit. The electrical supply and safety functions shall originate from the main refrigeration distribution board in the plant room. In the satellite dis. board, protective devices shall be installed for the power devices and regulation for the refrigeration unit.
Example of a refrigerated unit satellite dis. panel
The refrigeration contractor is responsible for the electrical supply and the connection between the main distribution board and the satellite boards. The refrigeration contractor is likewise responsible for connecting the satellite boards to the regulators and to the power devices in the unit. The lighting shall be connected up by an electrician. If the satellites are to be placed below the refrigerated units, they shall be raised up off the floor.
Example of a satellite placed on the floor
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The armatures of chiller and freezer cabinets shall be arranged as shown below: - Stop-valves on each cabinet module. - All armatures must be readily accessible. All passages of piping and electrical routing shall be sealed by the refrigeration contractor. All holes for connecting up refrigerated units (refrigeration/drains/electricity) shall be drawn by the refrigeration contractor on the co-ordination plan for the store, as well as being marked in situ. Clearly, there must also be co-ordination with the other trades present, as well as compliance with the specific features of the building (e.g. pre-stressing, etc.) Only 3 holes must be made for each cabinet module (1 each for refrigeration/drains/electricity). It is vital that the number of holes be optimized, in order to minimize the number. The installation of the water discharge (including trap) between the connection on the refrigerated unit and the floor connection shall be carried out by the refrigeration engineer. The drain (min. diameter 40 mm) must be installed with an adequate fall.
Example of a water drain beneath the refrigerated unit
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3.3.3 COLD ROOMS AND FREEZER ROOMS The supply boundaries as per sheet 2597S5 form an integral part of these technical definitions. The evaporators used must be proof-tested (except for evaporators for restoration). Spare parts must be available in case of need within reasonable lead-times. Cold rooms and freezer rooms with direct evaporation using R744 must be regulated in such a way as to minimize the pressure increase in the suction pipe during a failure in the installation. Ventilations, expansion valves, and electric defrost heating must stop automatically when a fault appears and start up again once the fault has been corrected. Cold room and freezer room evaporators must be installed using corrosion-resistant fixings. Refrigerated areas holding merchandise containing vinegar or salt, or where the atmosphere is corrosive, shall be fitted with evaporators with anti-corrosion protection. For example:
Description piping fins panels
Fruit & veg cold rooms (e.g. Küba V6.04)
Copper Bladegold (Alu-Goldlack)
Alu
Dairy product cold rooms (e.g. Küba V6.04)
Copper Bladegold (Alu-Goldlack)
Alu
Fish cold rooms (e.g. Küba V6.02)
Stainless Gold (Goldlack) Stainless
Thermostats, sensors, and thermometers shall be mounted on a common panel, adjacent to the evaporator, on the wall at a minimum height of 220 cm. If the height of the room does not allow this measurement to be complied with, the sensor panel shall be mounted as high as possible. Electrical cables must not be run directly into devices (e.g. alarm button) through the wall/insulation.
Example of configuration for temperature sensor and thermometer panel
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Freezer rooms with rendered ceilings (conventional construction) shall be fitted with a suitable protective plate between the ceiling and the evaporator, adjoining the end wall of the room and overhanging the evaporator by a minimum of 70 cm. The drains (including trap) between the evaporator and the connection point outside the cold room / freezer (pre-installed) shall be installed by the refrigeration engineer. The drain (min. diameter 50 mm) must be installed with an adequate fall (cold rooms min. 5° and freezer rooms min. 10°). In every cold room with evaporators using R744, the concentration of CO2 in the air must be monitored using infra-red detectors. When the limit value is exceeded, an alarm must be set off inside and outside at the entrance to the room, using a flashing illuminated warning device clearly indicating the danger. See also Section 6.2. Evaporators fitted with electric defrosting, fitted in both cold and freezer rooms, must be fitted with an insulating batt in order to compartmentalize the evaporator from the room ceiling. Cold room and freezer evaporators must be fitted with a minimum of 2 fans. All evaporators to be used in cold rooms and freezers shall be fitted with low-consumption fans (electronically-commutated [EC] motors). Drain heating shall be accomplished using a self-regulating system. Cold room and freezer evaporators shall be selected with fin spacing of at least:
Description Evaporator fin spacing
General cold room 4.5 mm
Fruit & veg cold room 7 mm
Dairy product cold room 4.5 mm
Meat cold room 4.5 mm
Bakery cold room 12 mm
Store freezer room 7 mm
Bakery freezer room 12 mm
The evaporator shall be fitted with a readily-accessible point for measuring the pressure. The evaporator position shall be suitable for the room conditions. It is important to guard against air ‘short-circuits’, and to avoid blowing directly into a freezer or cold room. These situations are to be avoided whenever possible. The evaporator positions marked in red are only possible if no other solution is possible.
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Do not position the evaporator above the door and do not direct the air flow towards the door.
Fit two-port evaporators. In long, narrow cold rooms Air directed towards the doors In wide cold rooms Air directed towards the walls
Fit either 2 evaporators or a two-port evaporator.
Do not position the freezer evaporator blowing towards the cold-room door. Do not position the cold-room evaporator blowing towards the freezer door; in this case, position the evaporator blowing towards the cold-room door.
Each cold room shall be fitted with a display giving temperature, defrost, and alarm information. The display must indicate the actual cold-room temperature.
Each cold room shall be fitted with a prominent label indicating defrost times and intervals.
For the type of defrosting for cold rooms and freezers, the following instructions shall be adhered to. If the number of defrosting operations set during commissioning and the optimization phase are no longer enough, the causes must be found and eliminated. Six months after the refrigeration installation is commissioned, the number of defrost operations may be adapted specifically to each store.
Description Type of defrost Max. number of defrosts per day
Cold room temperature > +2 °C fan-assisted maximum 3 times
Cold room temperature < +2 °C electric maximum 3 times
Freezer room electric maximum 3 times
Defrosting operations must take place as far as possible outside store opening hours and shall be kept to a strict minimum.
Cold room Freezer room
Evaporator
Evaporator
Evaporator
Evaporator
E
vapora
tor
Evapora
tor
Cold room or
freezer room
Evaporator
Evapora
tor
Evapora
tor
Evaporator
Cold room or
freezer room
Evaporator
Evaporator
Evapora
tor
Cold room or
freezer room
Evapora
tor
Evapora
tor
Évaporateur
Evaporator
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After defrosting, re-starting of freezer room evaporator fans must be delayed. When users have to enter the freezer room, a switch shall be provided for them to stop the refrigeration and ventilation for around 3 minutes.
The safety devices for the door frame heating and the equalizing valve must be fitted in the satellite where the refrigeration unit regulating control is located.
Example of pressure equalizing valve with heating
Satellite distribution boards for cold rooms and freezer rooms. A satellite distribution board must be fitted adjacent to each refrigeration cell (not over the door mechanism). The electrical supply and safety functions shall originate from the main refrigeration distribution board in the plant room. In the satellite dis. board, protective devices shall be installed for the load devices and regulating the cold room refrigeration unit. The refrigeration contractor is responsible for the electrical supply and the connection between the main distribution board and the satellite boards. The refrigeration contractor is likewise responsible for connecting the satellite boards to the regulators and to the power devices in the cold room. The safety functions for the following load devices must be provided separately (not by the satellite): Refrigerated room lighting (responsibility of the PO; connection to a maintained supply must be examined for each new configuration) - Personnel alarm for freezer rooms (powered from PO’s UPS or self-contained battery) - Floor heating for freezer rooms (from refrigeration satellite dis. board) - Air curtains for freezer rooms (from refrigeration satellite dis. board)
Example of freezer room floor heating
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Example of air curtain
Adjacent to the door of the freezer room or near the satellite dis. board, a label must be fitted with a message drawing users’ attention to the fact that the frame heating must also be turned off when the freezer room is turned off. Points where refrigeration and drain piping pass, as well as cables, must be sealed by the insulation contractor. The personnel alarm emergency button must be positioned near the door. It shall be positioned as per the standards, but at a max. of 30 cm above floor level, in a recess provided for this purpose. This recess shall be produced by the insulation contractor. The personnel alarm must be repeated outside the building. The personnel alarm facilities must be made secure by the use of a UPS. Surface wiring to the personnel alarm button.
Example of alarm button for trapped persons
Cold room lighting shall be controlled using a movement detector, fitted by the electrician. The electrician is responsible for the positioning of these detectors. Cold / freezer room cool-down must be accomplished in a staged manner, in accordance with the indications and instructions from the floor supplier. The refrigeration engineer shall seek information and it is imperative that they ensure the pre-determined cooling curve is adhered to. During the cool-down phase, the ambient temperatures must be recorded and presented to the project owner on request.
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Example of a temperature/time curve:
Cool-down in days
Am
bie
nt
tem
pe
ratu
re (
°C)
commissioning
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3.4 OPERATING RATES AND POWERS 3.4.1 BOOSTER CONFIGURATION AND RATES Depend on the climatic conditions in the country. To be verified and adapted if necessary. The following data are to be adhered to when sizing a booster or a chiller multiplex. Fundamentally, the manufacturer’s data take precedence. Rates Minimum values Target values Maximum
values Actual values
depending on
country
Chiller evaporation temperature
max. 2 K lower than the refrigeration
units’ evap. temp.
−9 °C −9 °C − °C
Freezer evaporation temperature
max. 2 K lower than the refrigeration
units’ evap. temp.
−33 °C −33 °C − °C
Freezer installation condensation temperature
Corresponds to the evaporation temperature of the chiller installation
− °C
Return pressure in summer (with atomizer)
min. 80 bar min. gas cooler output temperature ( °C) × factor
of 2.55
max. 85 bar bar
Return pressure in summer (w/o atomizer)
min. 90 bar min. gas cooler output temperature ( °C) × factor
of 2.55
max. 100 bar bar
Return pressure in winter min. 45 bar 45 bar max. 50 bar bar
Mean pressure min. 34 bar 35 bar max. 38 bar bar
Max. outdoor temperature (wet bulb) for sizing with atomizer*
min. +30 °C +31 °C max. +33 °C + °C
Max. outdoor temperature w/o atomizer*
min. +32 °C +34 °C max. +37 °C, otherwise warning to
FCAG
+ °C
Gas cooler output temperature (with atomizer)*
2K higher than incoming air temp. (wet bulb)
max. +35 °C + °C
Gas cooler output temperature (w/o atomizer)*
2K higher than incoming air temp. max. +39 °C + °C
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Suction temperature at chiller compressors (min. 10K super-heating between evaporator output and compressor output)
min. ±0 °C +5 °C In booster installations, the temperature is influenced by the freezer installation
max. +10 °C + ____ °C
Suction temperature at freezer compressors (min. 10K super-heating between evaporator output and compressor output)
min. −7 °C −9 °C max. −10 °C − ____ °C
Liquid temperature at sub-cooler output
min. 4 K sub-cooling required ____ K
Useful super-heating min. 6 K 8 K max. 8 K ____ K
Compressor speed 1,450 rpm 1,450 rpm max. 2,900 rpm
_____ rpm
Chiller simultaneity factor min. 90% 95% max. 110% ____ %
Freezer simultaneity factor min. 95% 95% max. 110% ____ %
* See gas cooler sizing Section 3.4.6 Chiller: The refrigeration power to be taken into account in sizing central refrigeration units shall be the total power with a frequency controller setting of 100%. Voltages to be verified for each country Chiller compressor no. 1 with speed control for proportional adjustment according to the evaporation pressure, with sinewave filter (if necessary) and cooling provided. Compressor 1 must be sized such that the part-charge and summer and winter operation rates function without significant fluctuation of the compressor. The refrigeration power of the chiller stage shall comprise the power of the chiller units and that of the freezer stage return (for boosters only). The minimum and maximum number of compressors per multiplex is to be respected. Each installation shall require a minimum of 4 compressors and a maximum of 6. Above a refrigeration power of 200 kW, provision must be made for at least 2 installations. Above a refrigeration power of 400 kW, provision must be made for at least 3 installations. Care must be taken that in winter periods with partial charge, the size of the compressors makes it possible to ensure correct operation of the installation. The multiplex must be sized in such a way as to be able to handle a minimum partial charge power equivalent to 10% of the maximum charge refrigeration capacity.
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Freezer: The refrigeration power to be taken into account in sizing central refrigeration units shall be the total power with a frequency controller setting of 100%. Voltages to be verified for each country Freezer compressor no. 1 with speed control for proportional adjustment according to the evaporation pressure, with sinewave filter (if necessary) and cooling provided. Compressor 1 must be sized such that the part-charge and summer and winter operation rates function without significant fluctuation of the compressor. The refrigeration power of the freezer stage shall comprises the power of the freezer units. Each installation shall require a minimum of 3 compressors and a maximum of 5. Above a refrigeration power of 50 kW, provision must be made for at least 2 installations. Above a refrigeration power of 100 kW, provision must be made for at least 3 installations. When 2 chiller installations have to be installed, check if it is necessary to double-up the freezer installation from the point of view of redundancy. 3.4.2 LABORATORY OR WORKROOM Dependent on the climatic conditions in the country. To be verified and adapted if necessary. Corridors are not to be cooled. For cooling of the LABORATORY or WORKROOM, the following variants should be examined on the basis of the power: - Connection to the booster (with no separate compressor/installation) up to a maximum
of 20 kW
- Connection to the refrigeration installation booster, but with a separate, independent compressor with higher evaporation temperature (see table below)
- Completely separate CO2 refrigeration installation with several compressors and higher evaporation pressure (see table below)
Rates Minimum values Target values Maximum
values Actual values depending on country
Evaporation temperature max. 2 K lower than the refrigeration units’ evap. temp.
−2 °C −2 °C − °C
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3.4.3 EXCHANGER FOR FLASHGAS SUPER-HEATING In the absence of any specification in terms of plate exchanger manufacturers, only recognized makes of exchanger are to be used. Spare parts must be available in case of need within reasonable lead-times. These plate exchangers must be connected up in accordance with the manufacturer’s data. They must generally be connected up so as to obtain opposite flow directions between the exchanger primary and secondary. The gas temperature at compressor inlets must be able to generate a minimum of 10 K
super-heating in all the operating levels for the installation.
General observations R-744 Target values
Actual values
depending on country
Maximum operating pressure (OP) at least min. 42 bar ____ bar
Maximum operating temperature (OT) at least +120 °C ____ °C
R-744 primary side (biphase) Target
values Actual values depending on country
Pressure 35 bar ____ bar
Input temperature ± 0 °C ____ °C
Output temperature ± 0 °C ____ °C
Input vapour content 45 % ____ %
Output vapour content 42 % ____ %
Max. pressure drop max. 50 kPa _____ kPa
R-744 secondary side (flashgas) Target
values Actual values depending on country
Evaporation temperature −8 °C ____ °C
Input vapour content 98 % ____ %
Output vapour content 100 % ____ %
Suction output temperature min. > −3 °C ____ °C
Max. pressure drop max. 30 kPa _____ kPa
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3.4.4 EXCHANGER FOR LIQUID SUBCOOLING In the absence of any specification in terms of plate exchanger manufacturers, only recognized makes of exchanger are to be used. Spare parts must be available in case of need within reasonable lead-times. These plate exchangers must be connected up in accordance with the manufacturer’s data. They must generally be connected up so as to obtain opposite flow directions between the exchanger primary and secondary. Liquid subcooling of 4 K must be guaranteed at the evaporator inputs.
General observations R-744 Target values
Actual values
depending on country
Maximum operating pressure (OP) at least min. 42 bar bar
Maximum operating temperature (OT) at least +120 °C °C
R-744 subcooling primary side Target
values Actual values
depending on country
Saturation pressure ± 0 °C ____ °C
Input temperature ± 0 °C ____ °C
Output temperature min. < −4 °C ____ °C
Max. pressure drop max. 20 kPa _____ kPa
R-744 (evaporation) secondary side Target
values Actual values
depending on country
Evaporation temperature −8 °C ____ °C
Liquid inlet saturation pressure ± 0 °C ____ °C
Liquid inlet temperature ± 0 °C ____ °C
Suction output temperature min. > −3 °C ____ °C
Super-heating 8K ____ K
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3.4.5 DE-SUPERHEATER, FREEZER INSTALLATION Dependent on the climatic conditions in the country. To be verified and adapted if necessary. In the absence of any specification in terms of de-superheater manufacturers, only recognized makes of de-superheater are to be used. Spare parts must be available in case of need within reasonable lead-times. The permitted sound level for the sizing of these elements must correspond to the order on noise protection. The constraints due to the layout and geography of the premises must also be taken into account in selecting the device. In order to reduce the effect of pulsations in the de-superheater, it is wise to fit a muffler at the refrigerating unit. If there is a significant risk of the refrigerant’s liquefying due to low outdoor temperatures, an automatic bypass will have to be installed. The speed of the de-superheater’s EC fan shall be modulated using a variable-frequency controller. General observations R-744 Target values Actual
values depending on country
Materials (heat exchanger) Stainless or copper
Materials (fins) Alu
Materials (housing) Galvanized steel, composite
paint
Maximum operating pressure (OP) at least min. 42 bar ____ bar
Maximum operating temperature (OT) at least +120 °C ____ °C
Fin spacing min. 2.1mm ____ mm
Pressure drop max. 1.0 bar ____ bar
Sound level @ 5 m max. 50 dB(A) ____ dB(A)
R-744 de-superheater Target values Actual
values depending on country
Hot gas inlet temperature +80 °C ____ °C
Hot gas output temperature max. +45 °C ____ °C
Outdoor air temperature +34 °C ____ °C
Max. refrigerant pressure drop max. 40 kPa _____ kPa
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3.4.6 GAS COOLER RATES AND CONFIGURATION Dependent on the climatic conditions in the country. To be verified and adapted if necessary. The power to be taken into account in selecting the gas coolers and piping is the power of the central refrigeration unit at its 100 % operating level. In the absence of any specification in terms of gas cooler manufacturers, only recognized makes of gas cooler are to be used. Spare parts must be available in case of need within reasonable lead-times. The permitted sound level for the sizing of these elements must correspond to the Order on noise protection. The constraints due to the layout and geography of the premises also need to be taken into account in selecting the device. If several gas coolers are connected in parallel on the same installation, the return feeds shall be connected separately to the liquid receiver. For high-power installations with / or high outdoor temperature conditions, the use of atomized water must be verified. The decision to use a gas cooler with atomized water cooling shall be made in each country, according to its mean annual outdoor temperature. Gas coolers using atomizing shall ideally be executed with a V-shaped heat exchanger. Execution without water atomizing Execution with water atomizing
Example of gas cooler without atomizing
Example of gas cooler with atomizing
Water
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Decision matrix for using an atomizing system 1. Obtain graph of local cumulative temperature frequency
The diagram represents the cumulative number of hours against the outdoor temperature ( °C) in a diagram.
Diagram: Frequency, cumulative probability against outdoor temperature (calculation example) 2. Defining the design temperature (DT)
The sizing of the installation, such as for example the compressors, gas cooler, etc. must be calculated at the design temperature. “Design Temperature” is defined as the temperature limit that the outdoor temperature does not exceed for more than 10 hours per year.
3. Determining the median temperature (MT)
The median temperature is the temperature limit where half the annual operating hours are above/below it. Alternatively, the average annual temperature may also be taken.
α coefficient against outdoor temperature Ta (calculation example)
∝-V
alu
e [
-]
Outside temperature Ta [°C]
∆∝ Atomisation
< 31 Not recommended
31 – 33 Weight
> 33 Recommended
Overall
Cu
mu
lati
ve
fre
qu
en
cy
[h
rs/y
r]
Outside temperature Ta [°C]
Key
LT Atomisation temperature
DT Design temperature
MT Mean temperature
Regional
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4. Determining the mean temperature α value Starting from the mean temperature, the αMT can be read off the diagram. The diagram is valid globally.
5. Determining the design temperature α coefficient
In a similar manner to point 4, starting from the design temperature, the αDT can be read off the diagram.
α-value as a function of outdoor temperature
Diagram: α coefficient with respect to outdoor temperature
6. Determining the difference between αMT and αDT
The difference between the two α coefficients is then derived: Δα = αMT – αDT 7. The decision whether to use atomizing or not is based on the difference Δα.
If Δα is greater than 33, atomizing should be used. If Δα is between 31–33, atomizing needs to be examined in terms of profitability. Below 31, atomizing need not be used.
8. Determining the atomizing temperature limit
If atomizing has to be installed, the start/stop atomizing temperature limit can be read off the cumulative temperature frequency graph. An atomizing system in which the gas cooler fins come into direct contact with the water must not be used for more than 200 hours a year.
CAUTION: The matrix takes only the basic design temperature into account. However, when sizing the gas coolers, it is necessary to take into account the maximum possible outdoor temperature, and if necessary, depending on the region, look into other kinds of cooling or other refrigeration systems (see Section 2.1).
∝-V
alu
e [
-]
Outside temperature Ta [°C]
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The refrigeration contractor shall be responsible for delivery and installation of the water atomizing system, including the atomizer piping and valves. When a water atomizing system is used for cooling the gas cooler, provision must be made for a water-softener in the system’s water supply. Water atomizing Target values Actual values
depending on country
Hardness of mains water supply min. 30°fH
Hardness of softened water (proposal) max. 0.5°fH
Peak hourly consumption min. 0.6m³/hr
Peak daily consumption min. 4.0m³/hr
Pressure drop max. 1.0 bar
Atomizer operating time max. 200 hr a year
In sizing the alternating water-softener, the gas cooler manufacturers’ data are to be taken into account and shall take precedence with respect to the values quoted in this document. The following rate data shall be determining for sizing the gas cooler. But in general the manufacturer’s data shall be taken into account. Account must be taken of the manufacturers’ objectives / installation directions. The following data are to be used for sizing the gas cooler. The manufacturer’s data take precedence. General observations R-744 Target values Actual
values depending on country
Materials (tube array) Stainless or copper
Fin material with water atomizing Alu, Epoxy
Fin material w/o water atomizing Alu
Materials (housing) Galvanized steel, composite paint
Maximum operating pressure (OP) min. 120 bar ____ bar
Maximum operating temperature (OT) +150 °C ____ °C
Coefficient of performance (COP) COP = power consumed PKL / Gas cooler power Qe = ≤ 3.5%
< 3.5% ____ %
Number of fans per unit min. 2 No. ____
Fin spacing min. 2.1mm ____ mm
Subcooling in winter min. 3 K ____ K
Pressure drop max. 1.0 bar ____ bar
Sound level @ 5 m max. 50 dB(A) ____ dB(A)
to be verified and adapted according to the location of the site and the country’s legislation
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Rate (with atomizing) Minimum values
Target values Maximum values
Actual values depending on country
Max. outdoor temperature (wet bulb) for sizing
min. +30 °C +31 °C max. +33 °C + °C
Return pressure in summer min. 80 bar Gas cooler output temperature ( °C) × factor of 2.55
max. 85 bar bar
Gas cooler input temperature summer
+100 °C +110 °C <0}max. + °C
Gas cooler output temperature 2K lower than the incoming air temperature (wet bulb)
<0}max. + °C
Gas cooler input temperature winter
+45 °C +55 °C +55 °C + °C
Condensation temperature winter
min. +10 °C min. +14 °C min. +15 °C + °C
Incoming air temperature winter
min. +5 °C min. +5 °C min. +10 °C + °C
Rate (w/o water atomizing) Minimum
values Target values Maximum
values Actual values depending on country
Max. outdoor temperature for sizing
min. +32 °C +34 °C max. +37 °C + °C
Return pressure in summer min. 88 bar Gas cooler output temperature ( °C) × factor of 2.55
max. 100 bar bar
Gas cooler input temperature in summer
+110 °C +120 °C max. +130 °C + °C
Gas cooler output temperature 2K greater than the incoming air temperature
max. +39 °C + °C
Gas cooler input temperature in winter
+45 °C +55 °C +55 °C + °C
Condensation temperature in winter
min. +10 °C min. +14 °C min. +15 °C + °C
Incoming air temperature in winter
min. +5 °C min. +5 °C min. +10 °C + °C
One factory-wired operating switch shall be installed per fan. All of the wiring shall be brought together on a terminal block inside an enclosure. The refrigeration contractor shall be responsible for ensuring that the element is delivered as requested.
For horizontally-operating gas coolers, the distance between the lower edge of the gas cooler and the ground must be a minimum of 1 metre.
Gas cooler refrigerant content is to be kept to a minimum.
A water supply and a power socket must be provided adjacent to the gas cooler for maintenance purposes. The refrigeration contractor is responsible for ensuring these elements are installed.
The spacing between the fins of the gas cooler register is to be adapted in accordance with the environment. The spacing must be 2.1 mm minimum.
Directive for locating gas coolers. Account must be taken of the manufacturers’ objectives /
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installation directions.
Clear horizontal location (1 gas cooler)
Clear horizontal location (several gas coolers)
Height of legs = 1 m min. Height of leg Height of leg Length Width Area for location = 2 × (device length + width) × leg height Height of legs = 1 m min. (to be adapted in accordance with the location)
Height of legs = 1.2 m min. Length Width Max. distance 100 mm
Area for location = 0.8 × device length × width × number of units Max. distance between units 100 mm Height of legs = 1.2 m min. (to be adapted in accordance with the location)
1 horizontal gas cooler alongside a wall 1 horizontal gas cooler alongside 2 walls
Height of legs = 1 m min. Length Width
Adapt the height of the legs so that the aspiration area is 0.8–1.0 × the exchange area (device length × width)
Minimum distance Length Width Minimum distance
Adapt the height of the legs so that the aspiration area is 0.8–1.0 × the exchange area
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Open vertical location (1 gas cooler)
1 vertical gas cooler alongside 2 walls
Direction of prevailing wind
Avoid installing the device so it blows into the wind
Height Minimum distance Length Minimum distance
Min. distance to wall for 1 row = device height × 0.8 2 rows = device height × 0.6 Distance to side wall for 1 row = device height × 0.5 min. 800 mm
V gas cooler, open location Gas cooler influence
Minimum distance Length
Min. distance between devices for 1 row = device length × 0.5
Do not position devices in series
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3.5 DESCRIPTION OF THE EQUIPMENT According to the French OESP [Pressurized Equipment Order] standard and the EN 378: 2008 standard for Europe, or as per local legislation. In terms of the pressure resistance of all the components, the contractor shall bear full responsibility for respecting the law and the standards. 3.5.1 REFRIGERATION, BOOSTER Pipework may be run in copper or stainless steel. This also includes the compressor connections. Pipework, insulation, and fitting must be carried out as per the technical data in Section 5.1. For chiller refrigeration, a minimum of 4 compressors must be used and a maximum of 6. Care must also be taken that in winter periods with partial charge, the size of the compressors makes it possible to ensure correct operation of the installation. Above 200 kW, provision must be made for 2 multiplexes (see Section 3.4.1) The installation must be sized in such a way as to be able to handle a minimum partial charge power equivalent to 10% of the maximum charge refrigeration capacity. Freezer refrigeration shall comprise a minimum of 3 compressors and a maximum of 5 per booster. Above 50 kW, provision must be made for 2 multiplexes (see Section 3.4.1) When 2 chiller installations have to be installed, check if it is necessary to double-up the freezer installation from the point of view of redundancy. Compressors shall be mainly semi-hermetic reciprocating types made by BITZER, BOCK, or DORIN, specially designed for optimum efficiency using R744. Electric motors shall be sized so as to be able to operate overspeed at a frequency of 70 Hz or higher (depending on voltage/frequency in the country) Chassis shall be fitted with anti-vibration pads. EACH COMPRESSOR SHALL BE FITTED WITH: - Suction valve - Return valve - Hot gas temperature transducer - Low pressure switch (manual mode pressure switch) - Safety valves and HP + LP pressure switches as per OESP - High pressure and low pressure pressure discharge device (compressor) 1 Electronic safety HP pressure limiter (pressure switch) 1 Electronic HP pressure limiter (pressure switch) - Connecting pipework compressor inlet to insulated liquid separator - Connecting pipework compressor outlet to insulated hot gas header - Case heater - Oil distribution system with ball valves and filter - Oil level or oil pressure (depending on type) control system - Oil cooling (as per supplier’s indications) - An oil circuit isolation valve
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1 BOOSTER SHALL BE FITTED WITH: - Chiller hot gas piping: Stainless, insulated as per Section 5.2 - Freezer hot gas piping: Copper, insulated as per Section 5.2 - Gas cooler return piping: Stainless, insulated as per Section 5.2 - Flashgas piping: Stainless, insulated as per Section 5.2 - Liquid piping: Stainless, insulated as per Section 5.2 - Chiller suction piping with flashgas: Stainless, insulated as per Section 5.2 - Chiller suction piping w/o flashgas: Stainless, insulated as per Section 5.2 - Freezer suction piping: Copper, insulated as per Section 5.2
1 Chiller suction header in stainless, insulated, including connections for suction piping, 1 angle valve and 1 drain cock
1 Chiller hot gas header in stainless, insulated, including connections for hot gas piping, 1 angle valve and 1 drain cock
1 Freezer suction header in stainless, insulated, including connections for suction piping, 1 angle valve and 1 drain cock
1 Freezer hot gas header in stainless, insulated, including connections for hot gas piping, 1 angle valve and 1 drain cock
1 Insulated chiller suction filter 2 Schrader valves 1 Manual full-bore stop valve in main suction pipe, insulated 1 Gas filler valve 1 Safety valve 1 Main safety valve fitted external to chiller units, opening pressure 42 bar, sized as per
relevant standards. Safety valve output discharge pipe, sized as per relevant standards.
1 Insulated freezer suction filter 2 Schrader valves 1 Manual full-bore stop valve in main suction pipe, insulated 1 Gas filler valve 1 Main safety valve fitted external to freezer units, opening pressure 24 bar, sized as per
relevant standards. Safety valve output discharge pipe, sized as per relevant standards. LIQUID SEPARATOR
Liquid tank
Level sensor
Safety valve
Changeover valve
Dryer
Lamp with humidity indication
Liquid filler valve
Safety valve
Ball valve
Measuring valve
Safety valve
Emergency generator for maintaining CO2 pressure
CO2 gas air cooler, ±0°C
CO2 compressors,
+30°C
CO2 supercooler, ±0°C
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Liquid separators shall be of vertical or horizontal type, fitted with: - Complete refrigerant receiver, insulated as per Section 5.2, including the necessary
safety and stop valves (no Rotalock valves), including connections and fixings, capacity sized as per the technical standards.
- Authorization, control, and verification of the liquid receivers, if necessary as per the OESP standard.
2 Refrigerant level detectors, including two alarms for low refrigerant level (pre-alarm and alarm)
1 Refrigerant level detector, including high refrigerant level alarm 2 Intermediate-pressure main safety valves, opening pressure: 42 bar, sized as per
relevant standards. Externally-fitted safety valves: fitting of external valves and piping from the booster. Safety valve output discharge pipes, sized as per relevant standards.
1 Replacement valve for main safety valves. 1 Dryer with interchangeable core, insulated 1 Sight-glass with humidity indicator 1 Liquid filler valve 1 Safety valves 3 Full-bore ball valves (dryer bypass) 2 Measurement valves 2 Liquid pipe safety valve - Isolation valve on gas cooler liquid return - The volume of the liquid separator must be correctly sized in order to ensure correct
operation at summer, winter, and heat-recovery rates - Liquid pipework shall be insulated, e.g. as per Section 5.2 or equivalent, between the
dryer output and the exchanger input.
1 PRESSURE MAINTENANCE WITH COOLING OFF (BACKUP) - Independent refrigeration unit allowing the CO2 to be liquefied when the main
refrigeration plant is stopped. This shall include the condenser, evaporator, solenoid valve, dryer, sight-glass with humidity indicator, thermostatic expansion valve, the regulation system, fixings, and minor hardware for fitting. Also included shall be the refrigeration connections, fitting, and commissioning
Under normal circumstances, the pressure maintenance with cooling off (backup) is powered from the refrigeration electrical distribution board, but in the event of an electricity outage, the supply must be provided from the building’s standby generator. If this is not possible, the refrigeration engineer shall be required to supply and fit a UPS to ensure operation in the event of an electricity outage. The pressure maintenance with cooling off (backup) must be tested automatically once a week.
1 Chiller high-pressure safety valve, opening pressure: 110 bar, sized as per relevant standards. Externally-fitted safety valves: fitting of external valves and piping from the booster. Safety valve output discharge pipes, sized as per relevant standards.
1 Freezer high-pressure safety valve, opening pressure: 42 bar, sized as per relevant standards. Externally-fitted safety valves: fitting of external valves and piping from the booster. Safety valve output discharge pipes, sized as per relevant standards.
3 Full-bore ball valves (gas cooler bypass) 1 Freezer manual hot gas stop valve 3 Full-bore ball valves (freezer de-superheater bypass)
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LIQUID SEPARATOR
Liquid separators shall be fitted in the chiller and freezer central refrigeration unit suction line. These accumulators will make it possible to avoid liquid reaching the booster. 1 Insulated chiller suction liquid separator 1 Oil return sight-glass 1 Manual stop valve 1 Solenoid valve - Oil return piping to the multiplex 1 Insulated freezer suction liquid separator 1 Oil return sight-glass 1 Manual stop valve 1 Solenoid valve - Oil return piping to the multiplex OIL CIRCUIT LINE
Suction pipe liquid separator
Manual stop valve
Magnetic valve
Oil return lamp
CO2 compressors, -9°C
Oil compressors
CO2 positive and
negative units, -9°C
Positive compressors
Negative compressors
Oil separator
Manual stop valve
Magnetic valve
Flowrate regulator valve
Oil tank
Oil filter
Indicator light on oil return pipe
Oil level regulation
Safety valve
Measuring valve
Differential pressure valve
Manual valve before each regulator
Gas air cooler
Positive units
Negative units
Per compressor
Per compressor
Liquid tank
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1 Insulated HP oil separator, with oil return piping, drain cock
1 Oil reservoir sized according to the power and minimum oil volume for each compressor 1 Safety valve 2 Pressure measurement connection and stop valves 1 Solenoid valve 4 Manual stop valves 1 Oil filter 1 Sight-glass on oil return pipe 1 Regulating valve 1 Discharge valve 1 Degassing pipe between oil reservoir and liquid receiver - Oil piping - Tapping points with isolating valves for supplying the various regulating and checking
devices (pressure gauge/switch/detector, etc.) - Manual isolating valves ahead of each compressor’s oil level regulator GENERAL: - Air oil cooler, including fixing, regulation, and connecting piping (depending on
compressor type).
- Oil pressure or level checker (depending on compressor type).
1 Filling with …..kg R-744 refrigerant, quality at least 4.5, guaranteed maximum humidity 100 ppm.
1 High-pressure filling hose, operating valve, safety relief valve, safety cable, pressure gauge, dryer, connections.
1 Filling with refrigeration oil
- Safety valves on pipes, if necessary in addition - Service valves on pipes or for pressure measurements, if necessary in addition.
1 Sturdily-built lacquered steel frame to take the above-mentioned machines and the electrical cabinets for the machines.
- The machine shall be assembled in such a way that each compressor can be removed easily by separating each element (all pipes must be removable).
- A discharge control system must be present for installations where the refrigerant capacity exceeds 300 kg. This is to verify that the safety valves have indeed operated and discharged gas. For example, a U-tube of oil with sight-glasses or a pressure controller with an alarm.
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CONTROL AND SAFETY PANEL Chiller low pressure suction
Freezer low pressure suction Intermediate pressure Chiller high pressure Freezer high pressure
Chiller suction Freezer suction Intermediate pressure Chiller high pressure Freezer high pressure
This panel shall include all the control and regulating organs such as: 1 High-pressure gauge (adjustable), stop valve, and connection for measuring pressure 1 Intermediate pressure gauge (adjustable), stop valve, and connection for measuring
pressure 1 Chiller suction pressure gauge (adjustable), stop valve, and connection for measuring
pressure 1 Freezer suction pressure gauge (adjustable), stop valve, and connection for measuring
pressure 1 Pre-alarm high-pressure safety pressure switch
1 Main high-pressure safety pressure switch 1 Intermediate pressure switch 1 Freezer installation high pressure switch 1 Chiller overall low-pressure safety pressure switch 1 Freezer overall low-pressure safety pressure switch - Pressure transducers (high pressure, intermediate pressure, low pressure)
System
System
System
System
System
Manometer, positive suction pressure Manometer, negative suction pressure Manometer, intermediate pressure High pressure manometer Positive low pressure manometer Manometer, negative low pressure Manometer, intermediate pressure
Positive safety pressure switch
Negative safety pressure switch
Intermediate pressure switch
Safety valve
Pressure limiter, high pressure alarm
High pressure switch
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EXCHANGER FOR FLASHGAS SUPERHEATING
The heat exchanger is fitted to the booster 4 Pressure measurement connection and operating valves HIGH-PRESSURE AND INTERMEDIATE-PRESSURE REGULATING VALVES PER BOOSTER 1 Electronic high-pressure regulating valve, c/w drive 1 Mechanical high-pressure regulating valve 1 Fine-mesh filters ahead of the high-pressure regulating valve 1 Electronic flashgas regulating valve, c/w drive 1 Mechanical flashgas regulating valve 4 Full-bore manual stop valves (high-pressure regulating valves) 4 Full-bore manual stop valves (flashgas regulating valves) 4 Pressure measurement connection and operating valves
Electronic high pressure regulator valve
High pressure regulator valve
Electronic flash gas regulator valve
Mechanical flash gas regulator valve
Manual stop valve
Measuring valve
Temperature sensor
High pressure regulation
Intermediate pressure regulator
Fine mesh filter
CO2 gas air cooler, +36°C
CO2 composite refrigeration, -2°C
Superheater
Medium pressure regulator valve
Tank, CO2 ±0°C
Tank, CO2 ±0°C
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EXCHANGER FOR LIQUID SUBCOOLING
The heat exchanger is fitted to the booster 1 Full-bore stop valve (liquid phase) 1 Full-bore stop valve (extracted gas) 3 Pressure measurement connection and service valves 1 Danfoss AKV 10 electronic expansion valve 1 Pressure transducer 1 Regulation, e.g. refrigeration unit regulator 1 Sector and discharge valve 1 Pressure measurement connection and operating valves 1 Temperature transducer including fitting and positioning
Stop valve
Electronic expansion valve
Pressure sensor
Temperature sensor
Regulation
Measuring valve
Safety valve Supercooler
CO2 compressor,
-2°C
CO2 positive and negative units, -2°C
Tank, CO2 ±0°C
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3.6 GAS COOLER Condensation/de-superheating of the R744 shall be accomplished using a spiral-type air gas cooler. As per the technical specifications 1 CO2 gas cooler for sub-critical and trans-critical operation with block optimized for sub-
critical operation - Vibration dampers, capable of withstanding the contact pressure and weather-resistant - Craning, positioning the element - Including EC fans + regulator for external 0–10 V signal - Where the air flow is vertical ↑, at least 1 m of aspiration must be ensured. - Factory-fitted operating switches (1 per fan), fitted adjacent to each fan and wired back
to a terminal block The permitted sound level for the gas cooler for the execution phase must be in line with the Noise Protection Order. The constraints due to the location, including the outdoor temperature, must likewise be taken into account and must be adapted according to the project. Reminder: The gas cooler must be selected for the booster power as per the rates in Section 3.4.6 and for the outdoor air temperature, depending on the climate in the country. When an atomizer system is used with a gas cooler, it is wise to make provision for a device for demineralizing the water.
Example of a water treatment installation for atomizing
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1 WATER DEMINERALIZATION INSTALLATION AS PER DESCRIPTION
Salt tank, filled, connected up, commissioned 2 Hoses - Supply of demineralizing salt, 50 kg min. - Discharge piping - Overflow pipes - Electronic regulation, including measuring and positioning elements - Water hardness test kit - Maintenance log - Supply piping to gas cooler for atomization 5 Stop valve 1 Non-return valve 1 Pressure reducer (if necessary) 1 Drain cock 2 Solenoid valves for atomization and draining - complete water atomization system, including nozzles and installing pipework
Salt reservoir
Flexible pipes
Magnetic valve, water vapour and drainage
Drainage valve
Stop valve
Non-return valve
Pressure reducer
Outside temperature Ta = +34°C
Interface, refrig. contr.
Sanitary interface
Gas air cooler
Automatic draining
Water softener
Mains water
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3.7 FREEZER DE-SUPERHEATER
The de-superheater shall make it possible to cool the freezer CO2 return down to a temperature 10 degrees above ambient temperature. No account shall be taken of the de-superheater in sizing the compressors and gas cooler. As per the technical specifications 1 Air-cooled de-superheater for cooling the hot gas in the freezer installation - Vibration dampers, capable of withstanding the contact pressure and weather-resistant - Craning, positioning the element - Including EC fans + regulator for external 0–10 V signal 2 Measurement valves - Provision must be made for bypass valves for bypassing the de-superheater in the event
of low outdoor temperatures
An example of a gas de-superheater for outdoor installation
Service valve
Temperature sensor
Regulator
De-superheater
Negative CO2 compressors, +80°C
Positive CO2 compressors, +45°C
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4 INDUSTRIAL REFRIGERATION SECTION REFRIGERATED UNITS
4.1 CHILLER AND FREEZER FIXTURES The fixture manufacturer supplies the electronic expansion unit and regulators, displays, and transducers with the units. Each unit must be standalone, and hence there is one regulator per unit. The refrigeration work package contractor must provide (see interface sheet 2597S2): - Connection to the alarm switch. - Electrical connections, including the communication bus. - Refrigerant connections. - Condensate connections (to connections pre-installed by structural work package). - Connection of the voltage-free contact from the store's BMS to an input of the
refrigeration installation's regulator system in the plant room (from the cable in the plant room that is not part of the food refrigeration work package).
Technical equipment to be supplied by the refrigeration work package: 2 Identified, sealed stop valve with built-in safety valve for each product section (maximum
of 4 refrigerated units) 2 Service valves for decompression - Connecting up display cabinet piping - Mounting hardware - Industrial refrigeration connections Technical equipment to be provided by the display cabinet supplier: 1 Special R-744 evaporator 1 Electronic R-744 expansion valve, Danfoss AKV 10 1 Temperature probe for expansion valve overheat - Regulator temperature probes, intake and outflow (min. 2 per unit) 1 Pressure transducer (1 for a maximum of 4 refrigerated units) 1 Temperature defrost probe (1 per unit) 1 Regulator displays, make and type to be indicated by the refrigeration contractor - Condensate drain with trap per connection - Electrical control boxes and protective boxes for the defrosting components, plus a fire
safety thermostat. - Machinery standards require the manufacturer to include an electrical cut-off system for
each unit. NB: The location and mounting of the probes is the sole responsibility of the manufacturer, who is also in the best position to know where best to fit them. If chiller fixtures are supplied with frame heaters, these shall not be connected up. The supplier of the refrigerated units must provide:
An electrical terminal strip onto which ventilation, lighting, heater cables and defrost elements are connected.
For electrical defrosting, the contactors for the defrost heating elements shall be as per reference.
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Example of a dis. board fitted with terminal blocks on a refrigerated unit
4.2 LABORATORIES AND COLD ROOMS For cold rooms, preparation cold rooms, and walk-in freezers, a CO2 detector shall be installed in any refrigerated spaces where the gas concentration might be exceeded. See Section 6.2.
In the event of an excessive gas level being detected, an audible and visual alarm shall clearly indicate that it is forbidden to enter and the need to leave the room, in accordance with current legislation.
Each cold room shall be fitted with one or more evaporators (see Section 3.3.3), each of which shall be equipped as follows: 1 Special evaporator for R-744 with EC motor as per description 1 Evaporator mounting element 1 Electronic R-744 expansion valve, Danfoss AKV 10 1 Temperature probe for expansion valve superheat 1 Pressure transducer (where necessary) 2 Sealed, identified stop valves 2 Service valves for decompression 1 Temperature transducer (regulation and alarm) 1 Temperature transducer (defrosting) in the case of electric defrosting 1 Self-regulating drain heater unit (when ambient temperature <+2 °C) 1 Analogue thermometer 1 Digital thermometer with position indicator 1 Dis. board for temperature transducers and thermometer 1 Drain trap per cold room
Each freezer room shall be fitted with one or more evaporators (see attached file), each of which shall be equipped as follows: 1 Special evaporator for R-744 with EC motor as per description 1 Evaporator mounting element 1 Electronic R-744 expansion valve, Danfoss AKV 10 1 Temperature probe for expansion valve superheat 1 Pressure transducer 2 Sealed, identified stop valves 2 Service valves for decompression 1 Temperature transducer (regulation and alarm) 1 Temperature transducer (defrosting) 1 Self-regulating drain heater unit - drain insulation as per Section 5.2 (in freezer rooms) 1 Trapped person alarm as per Section 6.3 (in freezer rooms) 1 Analogue thermometer 1 Digital thermometer with position indicator 1 Dis. board for temperature transducers and thermometer 1 Magnetic door contact
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1 Drain trap per freezer room
Example of an evaporator in a cold room
Example of a temperature transducer and thermometer panel in cold rooms and freezers
Example of a satellite unit
Example of a magnetic door contact
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4.2.1 REFRIGERATION AND CONDENSATE DRAIN CONNECTIONS Suction pipework insulated as per Section 5.2.
Liquid pipework insulated as per Section 5.2.
Condensate and defrost water drain in 50 mm Ø PE-HP, including trap, for cold rooms.
Condensate and defrost water drain in PE-HP (provided this meets local requirements) or V4A stainless-steel or copper, 50 mm Ø, with trace heating and insulation on the pipework, including trap, for freezer rooms.
All PVC drains visible to customers must be installed in white. As far as possible, all refrigeration circuits shall be run above the ceiling of cold rooms, where the cold rooms are accessible from above, or otherwise (if not accessible) within the cold rooms.
4.2.2 ELECTRICAL CONNECTIONS On the front of each cold room shall be fitted an electrical display unit (satellite) comprising:
A regulator
A contactor for the fans
A circuit-breaker for the supply to the regulator and fans
A circuit-breaker for the defrosting heating elements
A defrost contactor (freezer rooms)
An alarm relay
A differential circuit-breaker (30 mA) for the trace heating (freezer rooms)
A connecting terminal block using modular terminals (with spare capacity).
The refrigeration work package contractor shall be responsible for connecting up the decompression valve and supplying and connecting up the “trapped person” system
Freezer room floor heating (if necessary)
Freezer room cold air curtain (if necessary)
Freezer room door frame heating
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4.3 ICE MACHINE The ice generator is located either in the room above the cold room, with the ice delivered in wheeled bins to the fishmongery section, or above the fishmongery section itself.
Example of installation within the cold room and above it.
Example of an ice machine above the fishmongery section/ counter
The ice shall be directed via a guide channel into the ice bucket or bin. Possible products and the quantity of ice required are indicated by Carrefour (country-specific). Optional, depending on country requirements: Defrosting of the ice may be accomplished as per the following variants: - Natural melting depending on the ambient temperature (country-specific)
- Hot water – it is obligatory for this to be obtained from the refrigeration installation heat recovery facility.
- Ventilation with hot air over the fish counter, blowing hot air onto the ice. It is obligatory that this hot air is heated using heat recovery
- Separate area where the ice is melted using heating supplied from heat recovery.
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The minimum quantity of ice can be calculated using the diagram available below.
Quantity of ice required
Ice machine Target value Actual value, depending on country
Housing/body material Stainless steel
Ice machine material Stainless steel
Ice discharge pipe material Plastic or stainless steel
Type of ice as per Carrefour instructions
Daily ice output as per minimum daily quantity diagram or Carrefour instructions
4.3.1 EQUIPMENT, SUPPLIES - Ice-maker as per project owner’s specifications, completely in stainless steel, fully
independent production unit (separate refrigeration installation just for the ice machine) For ice machine installation within the cold room, appropriate measures must be taken to
avoid the ice-maker’s freezing up. 1 Electronic regulator, including external key-operated control panel, including 10 m of
cable, electrical power and control devices complete and ready to be connected, all wired up with a manual switch
1 Thermostatic expansion valve c/w necessary temperature transducers 1 Solenoid valve including coil 1 Evaporation pressure regulator
Qu
an
tité
de
gla
ce
(kg
)
Filling height 0.10m
Filling height 0.15m
Filling height 0.20m
Filling height 0.25m
Filling height 0.30m
Filling height 0.35m
Filling height 0.40m
Filling height 0.45m
Frozen surface
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4 Schrader connections 2 Ice machine stop valves 1 Refrigeration unit with liquid receiver, including all necessary safety devices (pressure
switches) 1 Outdoor air condenser with fan speed control (condenser installed outside the building) 2 Condenser stop valves - connecting pipework (suction and liquid / hot gas and condensate pipes) insulated as
per Section 5.2. - Ice machine and refrigeration unit alarm contact to main refrigeration plant electrical
cabinet under this contract. 1 Filled salt bin, size as per project owner’s information (including 1 spare fill) 1 Salt-water metering pump, flow rate according to ice machine requirements - Salt-water metering pump control, together with an alarm signal from it for the main
refrigeration plant electrical cabinet under this contract. 1 Ice guide channel in stainless steel or transparent plastic, as per project owner data - Vibration-damping supports - Sturdy stainless steel wall brackets or ceiling hangers for ice machine. - In the event of the ice machine’s being installed on the roof of the cold room, a retaining
tray shall be installed under the machine, including water outlet/drain pipe - Truck presence detector kit (automatic stop) and bin-full stop 1 Stainless steel or plastic channel, insulated using e.g. 19 mm Armaflex outside the cold
room - e.g. using Aeroflex insulation (passing through the cold-room wall), including fitting and
sealing - Vibration-damping supports - Small hardware and mounting hardware 2 Insulated plastic wheeled truck for transporting the ice, with inspection grille and drain
cock, capacity for approx. 400 litres of ice.
Example of a truck for transporting ice
As a variant, the contact to enable ice production may be accomplished by a voltage-free
contact from the BMS system rather than from the machine’s own regulation.
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4.4 COOLING THE PLANT ROOM Where the temperature in the plant room may exceed +30 °C, provision must be made for cooling, to be supplied by the refrigeration work package. Set-point temperature +30 °C. The plant room cooling shall operated via a split air-conditioning installation (inverter). The outdoor unit shall be housed in a weather- and corrosion-resistant housing. Electrically, the installation must be completely pre-wired. Powering shall be from the main refrigeration electrical distribution board. The installation must satisfy standards, prescriptions, and statutory stipulations (particularly EN 378).
Outdoor unit technical data Target value Actual value, depending on country
Refrigerant R410A, if possible CO2 or other natural liquid
Refrigeration power min. 6–13 kW ____ kW
Evaporation temperature +5 °C + ____ °C
Condensation temperature +46 °C + ____ °C
Incoming air temperature +35 °C + ____ °C
SPL @ 5 m 50 dB(A) ____ dB(A)
1 Air-cooled outdoor compressor/condenser unit - Possibility of external 0–10 V start command 1 Liquid shut-off valve in outdoor unit 1 Suction shut-off valve in outdoor unit 1 Winter regulation - Liquid pipework insulated as per Section 5.2 - Suction pipework insulated as per Section 5.2 - Anti-vibration elements - Small hardware and mounting hardware such as unions, weldable materials, clamps,
bolts, etc. - Refrigeration connections - Commissioning - Plant room temperature monitoring (hot and cold) by a regulator on the commercial
refrigeration installation, with connection to the remote monitoring system
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Indoor unit technical data Target value Actual value, depending on
country
Refrigerant R410A, if possible CO2 or other natural liquid
Refrigeration power min. 6–13 kW variable
____ kW
Evaporation temperature +5 °C + ____ °C
Incoming air temperature +27 °C + ____ °C
SPL @ 5 m 50 dB(A)
1 Indoor unit - Small hardware and mounting hardware such as unions, weldable materials, clamps,
bolts, etc. - Refrigeration connections Commissioning and start-up
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5 R744 REFRIGERATION INSULATION AND PIPING
5.1 TECHNICAL SPECIFICATIONS AND GENERAL POINTS, PIPING General According to the French OESP [Pressurized Equipment Order] standard and the EN 378: 2008 standard for Europe, or as per local legislation. In terms of the pressure resistance of all the components, the contractor shall bear full responsibility for respecting the law and the standards. The headers shall be determined in accordance with the distance and the refrigeration powers assigned to each circuit, taking the temperature schemes and programmed unit shutdowns such as butchery work area, delivery airlock, etc. into account in assigning the refrigeration units. Piping, pipe runs Refrigeration piping may be carried out in Cu-DHP copper (semi-annealed copper, refrigeration quality, material no. EN CW024A), corrosion-resistant stainless steel (1.4301, 1.4306, 1.4307, 1.4401, 1.4404, 1.4435) or in K65. The indications given in EN 378 and usual best professional practice must be observed and adhered to. If other materials are employed, this must be clarified in advance with the project owner. Copper refrigeration pipes must be brazed using special hard solder ensuring sufficient pressure resistance and under gas protection (forming gas) or using a flow-rate indicator. Proofs of adequate pressure strength and the wall thickness calculations for pipes and unions as per the Pressurized Devices Order are to be presented on request. The maximum permitted operating pressure for refrigerant pipes and valves etc. must, if necessary, be determined according to best professional practice, or if necessary in accordance with valid regulations. The combination of pressure and temperature shall always be determinant for the maximum permitted operating pressure in valves etc. and piping. For hot gas, the maximum temperature shall always be taken as at least +140 °C. In the case of minimum temperature, account must be taken of the fact that extremely low temperatures can arise during refrigerant filling. If the system is subject to other pressures, the protection and the possible pressure ranges of the components shall be adapted. In all cases, piping shall be degreased and delivered to the site with protective end caps. Overhead runs of suction and liquid pipes (fitted on brackets) shall be carried out in stainless steel or refrigeration-quality copper pipe, with sufficient fall to ensure natural oil return. Pipework shall be fixed in such a way as to avoid friction, vibration, or other mechanical stresses. Flexible hoses shall only be used if they satisfy the mechanical requirements in terms of safety. They must in particular withstand pressure peaks, vibration, permeability, and explosive decompression. In the case of vertical (and horizontal) suction and pressurized piping, special care shall be taken to ensure faultless transport of the oil under all operating conditions that arise. Risers shall allow efficient oil return, without excessive pressure loss, with trap and backflow preventer.
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All refrigeration pipes are to be fitted to the concrete floor slab. Fixing hardware such as stirrups, pipe collars, etc. shall be supplied and fitted by the refrigeration engineer. All refrigeration piping is to be fitted in such a way as to be free of oscillations and structure-borne noise (insulation level 98%). All piping is to be fitted with a sufficient number of flow direction arrows. The arrows must indicate the type of liquid and the physical state (in the case of refrigerant pipes). See Section 12.5 Calculation and operating points: In direct expansion installations, the pressure loss in the suction pipe, measured between the evaporator output of the most distant refrigerated unit and the compressor suction connector must not exceed the values below: Chiller installation: 1.5 bar and 2 K Freezer installation: 0.9 bar and 2 K In the case of execution using buried pipework, the contractor shall be responsible for the plastic sleeves, soldering/brazing/welding points shall be grouped together in the inspection chambers; in cases where there are no inspection points, the locating plans and the application of marker points on the tiling (to look into on site during the works) must allow reliable, fast, easy location for repair work in the event of leaks. All pipework that will be subsequently inaccessible shall have been pressure and vacuum tested. The contractor will be required to provide certification of its sealing. Upward-flow areas (see ‘industrial refrigeration’ section of ‘fitting instructions’ document): In the case of short areas of upwards flow on suction pipes, elbows and counter-elbows shall be installed. In the case of longer areas of upwards flow, double risers shall be fitted. In the case of short areas of upwards flow on hot gas pipes, elbows and counter-elbows shall be installed. In the case of long areas of upwards flow on hot gas pipes, elbows and counter-elbows shall be installed approx. every 4–6 m. In the case of long areas of upwards flow on gas cooler return pipes or liquid pipes, allowance shall be made for hammer because of the height difference. If the refrigeration installation is located lower than the refrigerated units, the risk of flashgas shall be taken into account. All soldered/welded/brazed joints concealed by insulation must be marked using adhesive tape.
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Outgoing feeds (see industrial refrigeration part of fitting instructions document): It is obligatory that suction pipe outlets shall be mounted upwards. The outgoing feed must be at least 45° with respect to the main pipe (oil). Outgoing liquid feeds should be introduced using a tee with the branch downwards (the main pipe is fed in at the bottom). If this is not possible, outgoing feeds must at least be made in a downwards direction. Safety relief valves All sections of lines must be fitted with section pressure discharge valves, if they can be closed in operation and may contain a certain amount of liquid, or if the gas temperature may be lower than the ambient temperature. The segment pressure discharge valve opening pressures must as far as possible be set 2 bar higher than the opening pressures of the main safety valves. Miscellaneous As far as possible, all joints must be soldered, welded or brazed. Screw or compression fittings shall only be used where soldering, welding or brazing are not possible, or where removable joins are necessary for repairing or maintaining the installation. Flange fittings are prohibited. Provision shall be made exclusively for shut-off valves with protective shroud. Under no circumstances must installations containing R744 refrigerant include elastomer hoses or any other form of piping in plastic. The chiller and freezer refrigeration has been determined for a compressor operating rate as per Section 3.4.1 and as per the terms of reference for the country. WARNING All soldering, brazing or welding operations are FORBIDDEN in the vicinity of cold rooms with open doors and/or unwrapped produce. In the event of contamination of fresh produce (particularly meat) by heavy metals, this work package shall be held responsible for the loss of merchandise and shall assume the financial and commercial consequences. In the event of loss of merchandise, the project owner will submit to the food refrigeration work package contractor an invoice, accompanied by the certificate from the Public Health authorities or the removal note from a knackery, or other regulations in force under local legislation.
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Implementation The R744 and Polyolester oil together form an aggressive solution. Hence special attention shall be paid to cleaning tubing: elimination of:
Oils and grease
Carbon and oxidation deposits, rust, etc.
Metal shavings, filings, burrs Consequently, it is imperative that tubing is cut using a pipe cutter; using a hacksaw is forbidden. Deburring, together with re-rounding of the tube if necessary, are obligatory in order to avoid creating additional resistance losses. Surfaces to be brazed shall be cleaned using steel wool or emery cloth; any other abrasives are prohibited. Brazing Brazing or silver-soldering must be carried out in a controlled inert gas atmosphere (Nitrogen R, forming gas) to avoid any internal oxidation that might generate carbon deposits or slag. Surface mounting Surface-mounted pipework shall be in stainless or refrigeration-quality copper tubing. Connections such as tees, elbows, etc. may be produced on site by tapping-in, bending, etc. or by the use of standard fittings. Embedded installation Embedded installation shall be carried out using annealed tubing; cold-drawn tubing may be used, but only on runs shorter than one length of pipe, with elbows produced by bending. In embedded installation, unions and even butt-joining pipe lengths is forbidden. The pipes shall be fitted in ducts or within insulating sleeves. This work package is responsible for these sleeves. The contractor shall take care that piping is not crushed, pinched, or deformed during the embedding operations, whether this work is performed by themselves or by the structural contractor. In the event of damage, the contractor is liable for replacing the part concerned; the circuit must then be pressurized in order to verify the sealing.
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5.2 TECHNICAL SPECIFICATIONS AND GENERAL POINTS, INSULATION Insulation is achieved using close-cell synthetic rubber foam, impermeable to water vapour. All pipework inside the building must be insulated. Provision shall be made for the minimum insulation thicknesses as per the table below. Insulation thickness must be specially adapted to each project and to specific local conditions, but it is obligatory that the prescribed minimum thicknesses be adhered to. The insulation material must have Microban antimicrobial protection and must meet the DIN EN 13501 European fire class certifications (min. B/BL-s3, d0 for pipework and at least B/BL-s3, d0 for insulating panels) or local stipulations. Valves and other such devices in suction and liquid pipes must be insulated. Insulating materials for refrigeration components: e.g. artificial synthetic rubber (e.g. EPDM) Water permeability (μ) Thermal
transmission (W/m*K) for ±0 °C
Minimum insulation thickness
Target Actual Target Actual Target Actual
Hot gas piping up to and with heat recovery
min. 5,000 min. 0.032
min. 25 mm
Hot gas piping from heat recovery min. 5,000 min. 0.032
min. 20 mm
Gas cooler flow and return lines min. 5,000 min. 0.032
min. 20 mm
Liquid pipes min. 10,000 min. 0.033
min. 20 mm
Chiller suction piping w/o flashgas
min. 10,000 min. 0.033
min. 20 mm
Chiller suction piping with flashgas
min. 10,000 min. 0.033
min. 20 mm
Freezer suction piping min. 10,000 min. 0.033
min. 32 mm
Liquid receiver/separator min. 10,000 min. 0.033
min. 32 mm
Freezer room drain min. 10,000 min. 0.033
min. 20 mm
Ice machine channels min. 10,000 min. 0.033
min. 20 mm
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Insulating materials for DHW components: e.g. PIR-Alu polyisocyanate duromer insulating materials Tank insulation using soft foam and quick-fit technique.
Water permeability (µ)
Thermal transmission
(W/m*K) for ±0 °C
Minimum insulation thickness
Target Actual Target Actual Target Actual
Heat recovery, domestic hot water (tank)
min. 0.035
min. 100 mm
DHW heat recovery, water side
min. 0.035
30 mm
Insulating materials for heating components: e.g. PIR-Alu polyisocyanate duromer insulating material Tank insulation using soft foam and quick-fit technique.
Water permeability (µ)
Thermal transmission
(W/m*K) for ±0 °C
Minimum insulation thickness
Target Actual Target Actual Target Actual
Heat recovery, heating hot water (tank)
min. 0.035
min. 100 mm
DHW heat recovery, water side
min. 0.035
30 mm
Halogen-free insulation may be used as long as it meets the prescribed values. These tables give the minimum values to be complied with when installing, on pain of rejection at acceptance, with an obligation to replace the insulation. Piping to be insulated shall first be cleaned and if necessary degreased; the latter is obligatory in the case of bonded fitting. The surfaces must be protected against corrosion. All straight sections of piping shall be insulated before being fitted to their supports. The internal diameter of the insulation tube shall be equal to or barely larger than the external diameter of the pipe being insulated. Collars and supports shall be fitted before the piping is run. After the installation has been sealing tested, the insulation shall be fitted at the position of welded/brazed/soldered joints, unions, and valves and their accessories, using split sleeves or appropriately-cut pieces of insulation, in such a way as to be an exact fit around the parts to be insulated. The adhesive used shall be that recommended by the insulation manufacturer, and shall be applied transversely and longitudinally so as to maintain the continuity of the insulation.
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Example of insulation on a refrigeration pipe
Example of insulation on a domestic hot water pipe
Example of insulation on a heating pipe
All suction and liquid pipes must be fitted with decoupled and thermally-insulated pipe clamps in such a way as to avoid the formation of condensation or ice.
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Insulating materials for clamps/shells: e.g. PUR/PIR (elastomer) body (e.g. EPDM)
Water permeability (µ)
Thermal transmission
(W/m*K) for ±0 °C
Minimum insulation thickness
Target Actual Target Actual Target Actual
Liquid pipes min. 7,000
min. 0.033
min. 20 mm
Chiller suction piping w/o flashgas
min. 7,000
min. 0.033
min. 20 mm
Chiller suction piping with flashgas
min. 7,000
min. 0.033
min. 20 mm
Freezer suction piping min. 7,000
min. 0.033
min. 32 mm
Hot gas, gas cooler flow/return, and heating and DHW piping are to be installed with traditional pipe clamps fitted with noise-reducing material. After installation, these shall be insulated using insulation as per Section 5.2. Clamps with shells shall be fitted externally with a layer of aluminium which contributes to stability as a vapour block for PUR/PIR sections. Tube fixing shall be provided by means of a rigid foam compartment. Fitting of PVC half-shells will be rejected and the installer will have to replace them with insulated supports at their own expense.
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Implementation It is obligatory for adjoining sleeves to be bonded together. The collars used shall be of standard type, with no resilient material. Valves and accessories to which access is required for verifying, maintenance, or other reasons, shall be fitted with removable insulating shrouds with quick-release catches. Operating hand-wheels and handles must remain accessible. Other refrigeration valves shall be insulated using a product identical to that used for insulating the pipe. Exterior coverings All insulation, piping and accessories, shall be protected by PVC cladding (UV- and volatile compound resistant). This cladding must be guaranteed. In all cases, sheet aluminium-type cladding must include 8 mm Ø holes every 50 cm, to drain off water ingress and/or condensation. Not necessary for suction pipes. All plaster cladding is strictly PROHIBITED. Prior to using any other insulation or cladding not described but equivalent or more suitable for certain uses, this must be proposed to the project owner or their consulting engineers in order to obtain their approval in writing.
Example of fixings for refrigeration pipes, liquid part
Example of gas cooler pipe fixings before and after insulation
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Example of DHW pipe fixings before and after insulation
Example of heating pipe fixings before and after insulation
5.3 DESCRIPTION OF REFRIGERATION PIPING/FITTINGS AND INSULATION The weight of the systems must be taken into account when calculating the supports. It must also be communicated to the project manager for checking the building structure. 5.3.1 SUCTION AND DISCHARGE LINE Complete circuit comprising piping, insulation, fittings, and cutting to length up to and with connection of the refrigerated positions, as per the technical specifications, commissioning as per the Pressurized Devices Order and the EN 378: 2008 standard or according to current local legislation. In terms of the pressure resistance of all the components, the contractor shall bear full responsibility for respecting the law and the standards. The price must include all minor hardware and tool for a complete circuit, ready to operate correctly.
5.3.2 HP, MP RETURN AND LIQUID RETURN LINES Complete circuit comprising piping, insulation, fittings, and cutting to length from the refrigeration unit and with connection to the gas cooler or liquid separator respectively, as per the technical specifications, commissioning as per the Pressurized Devices Order and the EN 378: 2008 standard or according to local legislation in force. In terms of the pressure resistance of all the components, the contractor shall bear full responsibility for respecting the law and the standards. Within the central technical unit and inside the building, hot gas and gas cooler return piping must be insulated.
5.3.3 BOOSTER REFRIGERATION CONNECTIONS All the suction, return, liquid flow and return headers shall be fabricated from stainless steel or refrigeration-grade copper, with cross-sections large enough to minimize pressure loss. Max. speed in suction header 2.5 m/s.
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6 SAFETY
6.1 PLANT ROOM CO2 DETECTION A CO2 detector shall be installed in the plant room, 40 cm above the floor, and shall operate: - the extract fan which must discharge the air outside the building - the flashing emergency warning signs inside and outside the plant room, marked: - “CO2 alarm – leave the room” - “CO2 alarm – do not enter room” A remote alarm shall be connected into the remote refrigeration monitoring system and as per local legislation. The electrical ventilation control shall be incorporated into the refrigeration control cabinet. The plant room ventilation is run by: a) The refrigerant gas alarm b) Manually, using a switch located on the front panel of the refrigeration control cabinet c) Manually, using a switch located outside the refrigeration plant room, adjacent to the
entrance door. Proposed limit values to be monitored as per EN 378. See in relation to local legislation
Main alarm
Target Actual
CO2 concentration in the air Min. 1.9 % vol. (19,000 ppm) ______ %vol. (_______ ppm)
Emergency illuminated visual and audible warning signals
Automatic triggering
Plant room ventilation Automatic triggering
Generating a technical alarm Priority 1
Alarm transmission to the refrigeration contractor
Alarm reset automatically
Example of gas detection sensor device with “Do not enter room” warning
6.1.1 EQUIPMENT DESCRIPTION Complete detection with detectors and illuminated warning signs with wording as per Section 6.1
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6.2 CO2 DETECTION FOR COLD ROOMS, FREEZER ROOMS, SALES AREA, AND ADJOINING ROOMS
A CO2 detector shall be installed in each cold room, preparation cold room, and freezer room at 40 cm above the floor and shall operate flashing illuminated emergency signs inside and outside the spaces marked: - “CO2 alarm - / leave the room” - “CO2 alarm - do not enter room” A remote alarm shall be connected into the remote refrigeration surveillance system and as per local legislation.
Main alarm
Target Actual
CO2 concentration in the air Min. 1.9 % vol. (19,000 ppm) ______ %vol. (_______ ppm)
Emergency illuminated visual and audible warning signals
Automatic triggering
Room ventilation Automatic triggering
Generating a technical alarm priority 1
Alarm transmission to the refrigeration contractor
Alarm reset automatically
Example of gas detection sensor device with “Do not enter room” warning
6.2.1 EQUIPMENT DESCRIPTION Complete detection with detectors and illuminated warning signs with wording as per Section 6.2
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6.3 FREEZER ROOM TRAPPED PERSON ALARM A ‘trapped person’ alarm shall be installed in every freezer room. As per local legislation When the alarm is set off, a signal parallel to the siren is sent directly to the remote management system. The trapped person alarm can only be stopped from inside the freezer room. Out of opening hours, the trapped person alarm is signalled directly via the remote management system and a voltage-free contact that is relayed to the project owner’s own security company (if there is one). If operated, the trapped person alarm shuts down the refrigeration and ventilation in the freezer room.
Example of a freezer room ‘trapped person’ alarm
a) Unit with warning sounder outside the room and b) Button inside the room
6.3.1 EQUIPMENT DESCRIPTION One ‘Trapped person’ alarm per freezer room as per Section 6.3 with: 1 Alarm device including safety button and shut-off switch 1 robust protective surround for safety button
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6.4 SECTION SAFETY AND CUT-OFF VALVES Each pressure range must be protected by main discharge valves (MDV). The actual safety valve operating pressures shall be set in such a way that they react before the section discharge valves (SDV) (lower pressure setting). In normal operation, only the main discharge valves (MDV) must react. In normal cases, the main discharge valves must be sized and set with the following ‘set-point’ pressure settings:
Sales area The section safety valves (SDV) are called upon to protect line sections in which an increase in pressure may occur due to a blockage and a heat contribution. Depending on how they are arranged, these SDVs are either active or inactive during normal operation. Inactive SDVs become active only by blocking the refrigerated unit.
Example of a connection to the refrigeration unit from below
In refrigeration units, it is possible to use shut-off valves instead of safety valves, but this requires that the shut-off valves be sealed and labelled to indicate that the pressure in the closed sector must be reduced below 6 bar.
Equipment for refrigeration units with safety valves
CO2
compressors
CO2 compressors
CO2 compressors
CO2 supercooler
CO2 supercooler
CO2 supercooler
NEW: Equipment for refrigeration units without safety valves
Three-way valve
Stop valve
Safety valve
Manual overpressure valve
Electronic expansion valve
Refrigeration unit
Stop valve with integral discharge flap-valve
CAUTION! Closure valves can be activated only by trained authorised personnel After closure, the pressure should immediately be reduced to under 6 bar.
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6.5 COMPRESSORS Depending on flow rate, compressors shall be fitted with a pressure switch or/and a pressure switch discharge device. A compressor pressure discharge device is usually set higher than the maximum permitted pressure for the installation and should not be used for protecting the installation or other components, unless it is set to the maximum permitted pressure. The statutory base is based on EN 378-2: 2008 +A1: 2009. Table 3 summarizes the requirement concerning pressure switches. Terminology and definitions:
Designation as per EN 378 Previous names
PSL Pressure switch (falling pressure) Low pressure switch
PSH Pressure switch (rising pressure) High pressure switch
PZL Pressure limiter (falling pressure) Safety low pressure switch
PZH Pressure limiter (rising pressure) Safety high pressure switch
PZLL Safety pressure limiter (falling pressure) Safety low pressure switch
PZHH Safety pressure limiter (rising pressure) Safety high pressure switch
Arrangement of pressure switches per compressor:
Compressor swept volume V' < 90 m³/h
Compressor swept volume V' < 90 m³/h
Charge < 100 kg
Charge ≥ 100 kg
Either variant 1 or variant 2
1 approved pressure switch (PSH)
(electrical in series): 1 approved pressure limiter
(PZH)
1 Approved safety pressure limiter (PZHH)
Variant 1: pressure discharge device with PS depending on installation
1 approved pressure limiter (PZH)
Variant 2: 1 pressure discharge device (PS
compressor) (electrical in series): 1 approved
pressure limiter (PZH) 1 safety pressure limiter
(PZHH)
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6.6 PLANT ROOM AIR EXTRACT VENTILATION The refrigeration engineer shall be responsible for fitting emergency ventilation in the central refrigeration plant room. The emergency ventilation shall not be used for cooling the machine room. Outline diagram of central refrigeration plant room ventilation installation:
*) Execute both speed when the air flow is substantial **) Only when sucking from outdoors
Example of an air extract ventilation device, including the switch fitted outside
The mechanical ventilation is only started up as a safety facility in the event of malfunction. The installation of this ventilation must comply with the relevant standards and directives. The extract fan is started either when the refrigerant detector is triggered or by manual operation of the switch. It discharges the extracted air directly to outside the refrigeration plant room. Fan starts immediately – refrigeration plant room motorized air extract and air intake flaps open – fire dampers already open. The expelled air must be discharged outdoors.
Fire-stop flap-valve
Corridors
Light switch
Voltage-free switch
Corridors
Fire-stop flap-
valve
From warehouse or outside
Refrigeration plant room
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The incoming air shall be drawn from outdoors or via a fire damper. Care shall be taken in positioning the air inlets and extracts to ensure that transverse ventilation occurs across the plant room. The refrigeration engineer shall scale the extract flow on the basis of the EN 378 standard, which gives the air flow calculation as follows:
Air flow = 14 × 10-3
× (refrigerant content of largest installation) × 3600 =
Example for a 200 kg load:
14 × 10-3 × 200 × 3600 = 1,723 rounded up to 1,800
In all cases, the minimum air flow must not be less than 1,000 .
If, when the size of the plant room is taken into account, the air renewal is less than 15× per hour, the ventilation shall be sized on the basis of air renewal. This means that a greater air flow will be necessary.
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6.7 EMERGENCY COOLING (OPTION) Emergency cooling is quoted as an option only, if the project owner wishes it. For the planning and operation of the emergency cooling, the following objectives shall be determining: The emergency cooling may only be used in an emergency. If it is observed to operate for lengthy periods without obvious cause, the cost of the water consumed will be billed to the refrigeration engineer. In the event of problems with the refrigeration installation that necessitate emergency cooling, the faults must be eliminated within a reasonable time and the emergency cooling stopped. Provision for emergency cooling is only made where a plate heat exchanger has been installed for heating hot water heat recovery. The procedure for starting and stopping it must be described in great detail and prominently displayed in the location. The various elements must be labelled accordingly. Emergency cooling for refrigeration installations with heating hot water heat recovery: The heating hot water heat exchanger is also used for the refrigeration installation’s emergency cooling, e.g. in the event of a malfunction in the gas cooler. The emergency cooling shall always be started up manually. To this end, provision shall be made in the electrical control cabinet for a switch for starting the emergency cooling. Starting the emergency cooling shuts down the heat recovery. When the emergency cooling is started, the refrigeration circuit 3-way regulation valve allows the refrigerant to pass through the heat exchanger. On the water side, the 2-way valve regulates and if this is not available, a water valve (option) controlled by the temperature in the discharge pipe adjusts the output temperature to the fixed value set to +40 °C. Operation of the emergency cooling must be notified and recorded as a Prio. 1 breakdown.
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Sizing of the emergency cooling heat exchanger using mains water: Rate Target Actual value,
depending on country
De-superheating power 100% at the emergency cooling high pressure
____ kW
Flow rate 100% of compressor High pressure 80 bar ____ bar
Incoming refrigerant temperature +110 °C + ____ °C
Outgoing refrigerant temperature < +45 °C + ____ °C
Incoming water temperature max. +15 °C + ____ °C
Outgoing water temperature max. +40 °C + ____ °C
Pressure drop, refrigeration side max. 40 kPa _____ kPa
Pressure drop, water side max. 25 kPa _____ kPa
Example of emergency cooling and connection
Heating water heat recovery Sanitary hot water
heat recovery or CO2 composite refrigeration, +110°C
Heating water heat recovery
CO2 gas air cooler, +45°C
Flowrate regulator valve
Optional
Emergency water cooler
Connection to emergency water cooler, 3 - 4 bar
To be connected only when emergency water cooling is required
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6.8 EMERGENCY STOP AS PER EN 378 For stopping the refrigeration installation, provision must be made a remote stop outside the plant room, adjacent to the door. The refrigeration engineer shall also make provision for a switch for this purpose in an appropriate location within the plant room. The switches must meet the emergency switch requirements as per EN ISO 13850 and EN 60204-1
a) Emergency stop switch inside plant room b) Emergency stop switch outside, together with plant room air extract ventilation switch
6.9 PLANT ROOM
The EN 378-3: 2008 standard shall form an integral part of the refrigeration plant stipulations. Local requirements are to be complied with. The plant room must have a sufficient number of outward-opening doors to ensure persons within the space can be rescued in the event of an emergency. The doors must have automatic closure devices and be able to be opened from inside (panic bars). Emergency exits and escape routes, if not immediately recognizable as such, must be indicated, preferably using pictograms. The refrigeration engineer must fit the following indicator signs outside the plant room.
Example ‘No smoking’ Example ‘No entry to unauthorized persons’
Condensed instructions for use as per EN 378
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7 HEAT RECOVERY 7.1 DEFINITION OF TERMS
HR = Heat recovery DHW = Domestic hot water CW = Cold water HHW = Heating hot water HE = Heat exchanger HW = Hot water
7.2 DECISION BASIS FOR DHW HEAT RECOVERY 1. Identify the consumers in detail and measure the additional pipe runs needed for
connection to the industrial refrigeration system.
Principle for determining the length of additional pipe runs
Conn
ectio
n to h
ea
t
recovery
circuit i.a
.w.
schem
atic d
iagra
m
Standard
Additional, plus-value
Daily water requirements [litres/day]
Additional pipe lengths (m) = l1 + l2 + … + ln
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2. Determine the consumer’s hot water requirements
Graph for determining the gain from DHW heat recovery of a given consumer
3. On the basis of the graph, it is possible to determine whether or not the consumer
should be connected to the DHW heat recovery system.
Ad
dit
ion
al p
ipe l
en
gth
s [
m]
Daily water requirements [litres/day]
Hot water preparation with heat recovery is sustainable but not financially viable
Transition zone (detailed
analysis necessary)
Hot water preparation with heat recovery is sustainable and
financially viable
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7.3 GENERAL Heat recovery for DHW shall always have a higher priority than for heating hot water. Heating hot water recovery is described in a separate document “Best Practice for heating hot water recovery”. Special country or local stipulations shall be taken into account. The refrigeration engineer remains responsible for installing, controlling, and regulating the recovery system, as well as for its faultless operation. If the set values are wrong or inappropriate handling of the hot water recovery system is noted, all related expenses together with the cost of the energy lost will be billed to the refrigeration engineer. Flow rate calculation:
Example of a flow rate calculation for a plate heat exchanger with a de-superheating power of 50 kW:
Sizing circulating pumps:
Rate Target value Actual value, depending on country
Primary liquid Drinking water
Type of construction Inline pump
Materials Grey cast-iron for the intermediate circuit and stainless steel for the load circuit
Minimum max. operating pressure (OP)
10 bar ____ bar
Minimum max. operating temperature (OT)
+110 °C + ____ °C
Flow rate as per separate formula ____ m³/h
Head as per system pressure loss calculation
____ m WATER
Electrical connection 1/230V ____ V Coefficient of performance (COP) Electrical power Gas cooler power
< 3.5% ____ %
Local specifications shall take priority over the above information.
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7.4 DOMESTIC HOT WATER Domestic hot water recovery shall be produced by a heat exchanger, including the intermediate circuit. Account shall be taken of the fact that the hot water must be softened in order to avoid scaling in the boiler. The de-superheating capacity shall be determined by the water consumption.
Fehler! Textmarke nicht definiert. The boiler capacity shall be sized on the basis of the water flow required. The ideal conditions for the boiler below shall also be taken into account:
1. Maximum height, taking into account the height of the space available
2. Diameter (max. Ø = 0.5 of the boiler’s height from the ground)
3. If necessary, couple a 2nd boiler in series.
CO2 compressors, +110°C
Sanitary hot water
recovery
Heat recovery fault
Heating water heat recovery or CO2 gas cooler, +45°C
Monitoring
Commercial refrigeration
Sanitari
Sanitary hot water recovery
Recovery between circulation
Circulating pump
Three-way regulator valve
Progressive valve
Ball valve
Safety and regulator sensor
Pressure monitor
Safety valve
NO magnetic valve
NC magnetic valve
Regulator
Emergency stop regulator
Sanitary hot water boiler
Cold water supply
Hot water supply
Circulation
Hot charge circuit connection
Cold charge circuit connection
Safety thermostat
Temperature regulator
Temperature sensor
230 V protective anode
Fuses for electric heating
Thermal safety
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Sizing exchanger 1 (refrigerant):
Rate Target value Actual value, depending on country
Primary liquid Refrigerant R-744 CO2
Secondary liquid Heating water
Materials stainless steel
Type of construction Tube bundle, coaxial, or plate heat exchanger
____
Maximum operating pressure (OP) at least
120 bar ____ bar
Maximum operating temperature (OT) at least
+140 °C + ____ °C
Superheat capacity as per separate formula; 30% of gas cooler power
____ kW
Flow rate 100% of compressor
High pressure 80 bar ____ bar
Incoming refrigerant temperature
+110 °C + ____ °C
Outgoing refrigerant temperature
Calculate, < +40 °C + ____ °C
Incoming water temperature +25 °C + ____ °C
Outgoing water temperature +58 °C + ____ °C
Pressure drop, refrigeration side
max. 40 kPa _____ kPa
Pressure drop, water side max. 25 kPa _____ kPa
Sizing boiler internal damper (intermediate circuit):
Rate Target value Actual value, depending on country
Primary liquid Heating water
Secondary liquid Drinking water
Materials Stainless steel
Type of construction Tube bundle ____
Maximum operating pressure (OP) at least
10 bar 10 bar
Maximum operating temperature (OT) at least
+100 °C +100 °C
Superheat capacity Same as exchanger 1
Incoming heating water temperature
Same as exchanger 1 + ____ °C
Outgoing heating water temperature
Same as exchanger 1 + ____ °C
Domestic hot water boiler incoming temperature
+15 °C + ____ °C
Domestic hot water boiler output temperature
+55 °C + ____ °C
Pressure drop, heating water max. 25 kPa _____ kPa
7.5 HEATING HOT WATER
Heating hot water recovery is described in a separate document “Best Practice for heating hot water recovery”.
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7.6 EQUIPMENT DESCRIPTION 7.6.1 DOMESTIC HOT WATER
7.6.1.1 DHW HEAT RECOVERY WITH HEAT EXCHANGER AND INTERMEDIATE
CIRCUIT
Fehler! Textmarke nicht definiert. The refrigeration engineer must supply and install the following components: - The heat exchanger, including insulation, shall be fitted to the booster - Exchanger 1, insulated as per Section 5.2 - Load circuit pump, make Grundfos (w/o speed regulation) or equivalent, insulated using
manufacturer’s insulating shell - 3-way regulating valve, make Siemens VVG 41 (with SQX 62 actuator) or equivalent, insulated
using manufacturer’s insulating shell - Ballorex / STA adjusting valves in the load circuit as per outline diagram - Regulating / safety probes, including thermowells - Sufficient measuring fittings for the system - Load circuit connecting piping to hot water cylinder, insulated as per Section 5.2 - Pressure monitoring for emergency changeover (automatic bypass) - Air bleed valves / drain cocks - 6 bar safety valves for the load circuit - Expansion vessel for load circuit, including pressure gauge and filling connector - Refrigerant bypass valves for bypassing the exchange - Refrigerant bypass valves for emergency changeover (bypass) > 2 no. normally open solenoid valves > 1 no. normally closed solenoid valve - Load circuit water analysis after 1 year in operation - Load circuit water analysis after 2 year in operation
CO2 compressors, +110°C
Sanitary hot water recovery
Heat recovery
fault Heating water heat recovery or CO2 gas cooler, +45°C
Monitoring
Commercial refrigeration Sanitary
Sanitary hot water recovery
Recovery between circulation
Circulating pump
Three-way regulator valve
Progressive valve
Ball valve
Safety and regulator sensor
Pressure monitor
Safety valve
NO magnetic valve
NC magnetic valve
Regulator
Emergency stop regulator
Sanitary hot water boiler
Cold water supply
Hot water supply
Circulation
Hot charge circuit connection
Cold charge circuit connection
Safety thermostat
Temperature regulator
Temperature sensor
230 V protective anode
Fuses for electric heating
Thermal safety
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Boiler equipment: 1 Boiler insulated using soft PU foam and PVC sheath, including cutting out holes ready
for the quick-fit connections (insulation as per Section 5.2), in gas-welded stainless-steel, and full insulation. Certified as per the stipulations specific to the country.
1 Introducing and positioning the boiler (water connection by the sanitation work package) 1 Cold water connection, min 1½", at bottom 1 Hot water connection, min. 1½", at top 1 Circulation connection, min. 1½", located in centre (if necessary) 1 Boiler internal coil, sized on the basis of the necessary capacity, located at the bottom,
as per outline diagram 1 6 bar safety valves (security valve) including discharge to drain - min. 4 probes, including thermowells (regulation) 1 Safety thermostat to shut down heat recovery in the event of overheating - min. 3 thermometers, including thermowells 1 230 V protective anode, if necessary 1 Additional electrical heating (sized according to the size of the boiler, to heat the water
within the boiler up to +60 °C within 12 hr); the heater unit will be verified by the heating installation, country-specific
1 Thermal discharge safety device, including discharge to drain - Service/inspection opening The sanitary plumbing installer will provide the following elements: - Main cold- and hot-water supply connections - Hot water circulating pump connection, including pump (if necessary) - Delivery, fitting, regulating, and commissioning hot water circulating pump
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7.7 REGULATING DESCRIPTION 7.7.1 HEAT RECOVERY, DOMESTIC HOT WATER
Fehler! Textmarke nicht definiert. Control / regulation: The domestic hot water supply shall be heated using the heat from the refrigeration circuit de-superheater via a booster refrigeration installation. Provision shall be made for heat recovery to be installed on the refrigeration installation having the greatest amount of heat. The high pressure for operating the recovery is not offset. The boiler probe (no. 2) starts the recovery process. This probe controls the refrigeration circuit 3-way bypass valve and the load circuit pump starts up. The exchanger output water temperature is adjusted to the desired value using a 3-way regulating valve, and the boiler is heated. If the desired exchanger output water temperature value is not reached, this is offset or reduced (time delay) in such a way that there is always a minimum flow to the boiler and that the latter can be heated to a lower temperature level. If the temperature in the boiler indicated by the probe (no. 1) is already higher than the hot gas input temperature, the recovery process will be stopped (time delay). If the desired temperature is reached at the probe (no. 4), the recovery process is stopped. All the set values and time delays must be freely adjustable. It shall be possible to visualize and record the whole of the heat recovery process through the remote monitoring system. Heater unit: If the desired boiler temperature is not reached and if a defined target value is not achieved at the probe (no. 1), the heater unit (heating) is started and the water is heated to the desired temperature. It must be possible to adjust the start and stop temperatures for the heater and heat recovery units independently of each other, and starting of the heater unit is to be notified as a Prio. 2 breakdown message. The regulation, including the starting command, for the heater unit is controlled by the refrigeration system.
CO2 compressors, +110°C
Sanitary hot water recovery
Heat recovery
fault Heating water heat recovery or CO2 gas cooler, +45°C
Monitoring
Commercial refrigeration Sanitary
Sanitary hot water recovery
Recovery between circulation
Circulating pump
Three-way regulator valve
Progressive valve
Ball valve
Safety and regulator sensor
Pressure monitor
Safety valve
NO magnetic valve
NC magnetic valve
Regulator
Emergency stop regulator
Sanitary hot water boiler
Cold water supply
Hot water supply
Circulation
Hot charge circuit connection
Cold charge circuit connection
Safety thermostat
Temperature regulator
Temperature sensor
230 V protective anode
Fuses for electric heating
Thermal safety
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Safety: The boiler must be protected against overheating on the one hand and over-pressure on the other. In the event of too high a temperature in the boiler, the heat recovery must be stopped via the probe (no. 1) or a safety thermostat and only started again when the water temperature reaches the predefined value. If excess pressure builds up in the boiler (e.g. because of a leak), the pressure monitoring shall stop the heat recovery system and the hot gas shall be bypassed directly to the gas cooler. The boiler must likewise be protected against over-pressure by a safety release valve. Excess temperature and over-pressure are both to be notified to remote management as Prio. 1 breakdowns. Setting parameters: The setting parameters are given as an indication only. They are to be optimized and adapted specifically for the purpose.
Regulation setting parameters Target value Actual value, depending on
country
Stage 1 input (probe no. 2) +50 °C + ____ °C
Stage 1 stop (probe no. 4) +52 °C + ____ °C
Stage 2 input (probe no. 2) +45 °C + ____ °C
Stage 2 stop (probe no. 4) +45 °C + ____ °C
Heating unit input (probe no. 1) +45 °C + ____ °C
Heating unit stop (probe no. 1) +50 °C + ____ °C
Safety stop +70 °C + ____ °C
Safety input +65 °C + ____ °C
Input circulation DHW
Circulation stop DHW
Monitoring intermediate circuit input pressure
5 bar ____ bar
Monitoring intermediate circuit stop pressure
4 bar ____ bar
Load starting temperature minimum setting (valve set to minimum flow)
+40 °C + ____ °C
Temperature difference for boiler temperature
5 K ____ K
Time delay for starting temperature offset 30 sec. ____ sec.
Time delay for stopping recovery because of low hot gas temperature
180 sec. ____ sec.
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8 REGULATION DESCRIPTION The regulation of CO2 installations is inherently more sensitive with respect to variations in refrigeration power requirements. Primarily because of the high pressures (small ‘cushions’ of gas) and the high volumetric heat capacity of CO2. It may be wise to adjust the setting parameters to a little “faster”. In practice, the objectives are generally achieved using the usual settings – however, very particular attention must be paid to the setting of the refrigeration points in order to avoid liquid reaching the compressors. Attention must be paid to the specific features of the different regulation system manufacturers. The regulation systems must have a “read only” function for the remote monitoring system (no management function) with the help of all the parameters, and the Log evaluations shall be able to be consulted remotely.
8.1 REFRIGERATION OUTPUT CO2 BOOSTER 8.1.1 NORMAL AUTOMATIC OPERATION Regulation of the chiller and freezer central refrigeration units shall be achieved via an electronic regulator with the ability to vary the number of compressor stages and fans in the gas cooler by using extension modules. The regulation system must have a consistent communication bus allowing all the adjusting devices in the system to communicate with each other. The following types are approved (inasmuch as the ‘read only’ function and the process diagram are possible):
- Carel, pRack series
- Danfoss, AK series
- Eckelmann, LDS series
- Wurm, Frigolink series
- Eliwell All adjustment values must be visible via the remote monitoring system. 8.1.2 MANUAL OR DEGRADED OPERATION Emergency manual compressor operation: In the event of a breakdown or regulation problem, the compressor must be able to continue running by means of manual high / low pressure switches. To achieve this, it must be possible to operate the compressors by means of an on-site switch (or control panels) and to switch them from automatic to manual mode. The switch position must be monitored. Emergency manual use of the high pressure regulating valve: In the event of a problem with the electronic high pressure regulating valve or with the high pressure regulating system, the mechanical high pressure regulating valve, installed in parallel, must be operated manually. When the refrigeration installation is commissioned, the valve shall be set to a specific pressure (e.g. 80 bar) so that it is ready for use in emergency operation. In the event of emergency operation, this operation must be monitored.
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Emergency manual use of the flashgas valve: In the event of a problem with the electronic flashgas regulating valve or with the flashgas regulating system, the mechanical flashgas regulating valve, installed in parallel, must be operated manually. When the refrigeration installation is commissioned, the valve shall be set to a specific pressure (e.g. 35 bar) so that it is ready for use in emergency operation. In the event of emergency operation, this operation must be monitored. Operation of the regulator in the event of breakdown/failure: All regulators must have a backup mode that makes it possible to set an imposed fixed value in the event of transducer failure. 8.1.3 REGULATION OF THE TRANSCRITICAL HIGH PRESSURE In the transcritical zone, the temperature and pressure are not explicitly dependent on each other. This is why it is necessary to have an additional high pressure valve that adjusts the high pressure in accordance with the gas cooler output temperature. In the subcritical zone, the high pressure is adjusted so that there is always subcooling of a few Kelvins. The graph below shows the theoretical high pressure values with respect to the gas cooler output temperature, as achieved by certain makes of regulation devices.
Diagram of high pressure with respect to gas cooler output temperature
Towards the high and low ends, the theoretical values are limited by a number of threshold values: the minimum high pressure and the condensation pressure depend on the compressor use limit and the maximum high pressure as a function of the application point with a maximum outdoor temperature or as a function of the sizing of the installation. This last point includes the compressor use limit, as well as the maximum pressures and temperatures for the installation with respect to high pressures. When setting the high and medium pressures, it is important to keep them as stable as possible. Instabilities may lead to the following: - Pressure peaks and triggering of the safety valves or pressure switches - The flashgas bypass stays closed too long: insufficient motor cooling and tripping of
the motor protection contactor and high suction gas temperatures
Pre
ss
ure
P [
bara
]
High pressure setpoint Critical point
[+31°C / 74 bara]
Two-phase region
Enthalpy [kJ/Kg]
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8.1.4 GAS COOLER REGULATION The gas cooler fan speeds shall be adjusted in accordance with the refrigerant gas output temperature. The refrigerant gas output temperature must be 2 K higher than the outdoor temperature. If the refrigerant gas output temperature exceeds this limit, the fan speed is increased. At refrigerant gas output temperatures above +20 °C, the fans run at maximum speed. A minimum speed is often laid down. In this way, more stable system operation is obtained. This increased speed is not a problem as long as the refrigerant gas output temperature is above +5 °C. The refrigerant gas output temperature must never fall below +5 °C; to achieve this, the speed offset must be disabled in the event of low outdoor temperatures. The graph below shows gas cooler output temperature with respect to outdoor temperature.
Example of gas cooler fan regulation
Atomizing: The atomizer is controlled in accordance with the outdoor temperature and the gas cooler output temperature (adjustable value). The fans and atomizer are controlled in accordance with the power demand.
Fan speed [%]
With a gas cooler outlet temperature ≥ +20°C fans rotate at
100%
The gas cooler outlet temperature must always be ≥ +5°C. Below an outlet
temperature of +5°C there is no minimum setpoint for the speed of the
fans.
The gas cooler outlet temperature is controlled by fan speed to be 2 K above
the outside temperature A minimum speed may be predefined for stable
operation.
Gas cooler outlet temperature [°C]
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8.2 REFRIGERATION UNITS
8.2.1 REGULATION OF CHILLER AND FREEZER REFRIGERATION UNITS For maintenance of the unit:
Unit is shut down from the remote monitoring system and the corresponding alarm bypassed
Faults and alarms are dealt with by addressing the regulators via the remote monitoring system
Alarm thresholds:
Low threshold, to avoid the products freezing
High threshold, to avoid exceeding the food standards, in accordance with legislation in force.
Unit by unit defrosting. Defrosting managed by time and/or by the end defrost probe (maximum number of defrosts as per Section 3.3). Confirmation of return to normal operation at end of defrosting via the interconnection bus. Handling of “defrost time too long” fault. If “defrost too long” fault, then re-start until regulation level is reached. Supply, fit, and connect up the protective circuit-breakers for all units. The supply, electrical and refrigeration connections of the various components for all units. Injection adjustment: The regulation of the superheating for these refrigeration units is more tricky than on ordinary installations, as CO2 has greater enthalpy (heat capacity) and the volumes in the evaporators are smaller. Particular attention must be paid in positioning the superheat temperature probes and when commissioning the refrigeration units. Chiller refrigerated fixture:
Temperature of the merchandise regulated by continuous or pulse-modulated electronic expansion valve as per PID, target value: merchandise temperature
Fans run constantly
No adjustment of superheating (it results from operation and is around 15 K), minimum superheating limitation.
Cold room and freezer room:
Temperature of the merchandise regulated by electronic expansion valve in thermostatic mode target value: merchandise temperature
Ventilation runs only during operation
Target values: merchandise temperature and superheating
During operation: Temperature of the merchandise regulated by continuous or pulse-modulated electronic expansion valve as per PID, target value: superheating e.g. 10 K
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Provision must be made for freezer unit regulators with the following adjustable MOP values:
t0 reaches MOP1: electronic expansion valve fully closed, setting e.g. −20 °C
t0 reaches MOP2: in addition, the refrigerated unit fans are stopped, setting e.g. −19 °C
This function makes it possible to avoid constant opening of the safety valve because of the heat input, which creates a pressure increase. Also advisable is a type of control such that complete failure of the freezer multiplex safety chain closes the electronic expansion valves on the freezer refrigeration units. Remark:
Danfoss (AKV) pulse-modulated electronic expansion valves require special (more powerful) solenoid coils for CO2. This is why it is vital to specify the refrigerant used (CO2) when ordering.
When electronic expansion valves are being commissioned on refrigeration units, the superheating must be set to a high enough value and then reduced.
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8.3 LIGHTING CONTROL On: The lighting for all refrigerated fixtures is powered when the store’s shelf stocking
lighting is turned on. When the night blind is opened using the zone switch, the refrigerated unit lighting comes on.
Off: The refrigerated unit lighting is turned off completely with the store lighting.
Sep
ara
te s
witch
for
blin
d
Exte
rna
l
sw
itch for
blin
d P
ow
er
su
pp
ly fro
m C
arr
efo
ur
ma
in
pane
l
Main
23
0V
/50H
z d
istr
ibutio
n
Lig
hting
Caution e
xte
rna
l vo
ltag
e
Nig
ht-
blin
d m
oto
r
(optio
na
l)
Openin
g n
ight-
blin
d:
- D
uring
op
enin
g w
ith 1
00
% s
hop lig
hting
-
Usin
g (
manu
al) s
witches w
ith 5
0%
sh
op lig
hting
Nig
ht-
blin
d c
losure
:
- W
he
n th
e s
hop
is c
losed a
nd t
he lig
hting t
urn
ed o
ff
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8.3.1 NIGHT BLIND CONTROL: Only for display cabinets with electric night blinds. See separate “Night blind” option documentation 8.3.2 NIGHT OFFSET: The night-time increase in evaporation temperature can be obviated if an offset is established for the store heat capacity and the effective evaporation temperature necessary at the multiplex. On: the night offset signal is activated when the lighting is turned off in the chiller and
freezer units. Off: If the lighting is turned on on the chiller and freezer units, the night set-point offset
must be disabled. 8.3.3 DEFROSTING REGULATION: Refrigerated fixtures shall be defrosted as a first priority by means of the ambient air. The number of defrost operations and the defrost time must be kept to a strict minimum. Refrigeration units shall be defrosted using ambient air or electrically. Freezer refrigeration units shall be defrosted electrically. Provision to be made to stop the outer air curtain from the regulator when the night blind is closed and in defrost mode for fixtures fitted with a double curtain, in accordance with manufacturer’s recommendations. Defrosting times shall be programmed:
spread at regular intervals throughout the day, for all defrost types (electric and fan-assisted)
separately distributed throughout the day in order to minimize electrical consumption peaks for all electric defrosts (this distribution shall take account of fixture defrosting)
In accordance with cold room activity, outside the times when the doors are assumed to be opened often and/or for a long time. For example, meat carcass cold rooms shall be defrosted outside the 4–6 am time slot.
A single sales display unit (adjoining units with no transparent separators) shall be defrosted all at the same time, even if the unit is supplied by 2 (or more) separate electric expansion valves. 8.3.4 EVAPORATION PRESSURE REGULATION Thanks to the good heat transfer characteristics and the LOW suction pipe pressure losses, the theoretical suction pressure value can be 1–2 K higher than for ordinary installations. Suction pressures of −9 °C or −35 °C and lower on the compressors are common. Evaporation temperatures must be adapted to the refrigeration installation in accordance with the enthalpy of the store and the effective evaporation temperature required. 8.3.5 DEW-POINT REGULATION Freezer fixture glazing and frame heating regulation must be carried out in accordance with the enthalpy of the store. To do this, the temperature and humidity are measured at a defined position in the store, which together determine a dew-point. The heaters are tacté/adjusted in accordance with the enthalpy.
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8.3.6 CHILLER AND FREEZER ROOM DOOR CONTACTS Cold room and freezer room doors shall be monitored using a door contact supplied and installed by the refrigeration engineer. If a door remains open for a given length of time (set to e.g. 60 min), a Priority 2 alarm shall be generated. The door open position must be signalled through the remote monitoring system. When the door contacts are fitted, account must be taken of the door frame heating and other installations. Supplied under Refrigeration work package 8.3.7 FREEZER ROOM AIR CURTAIN If freezer room doors are open, there is a rapid exchange of air because of the temperature difference. To reduce this problem, an airlock cold room must be installed whenever possible. If for constructional reasons this is not possible, it is absolutely essential to install an air curtain on the outside above the freezer room door. A door contact sets off the air curtain as soon as the freezer room is opened. It remains in operation as long as the door is open. Supply and fit by the cold room and freezer room manufacturer. 8.3.8 FREEZER ROOM FAN STOPPING If the evaporator continues to run with freezer room doors open, the hot, moist outside air is driven into the freezer room because of the significant exchange of air. This leads to icing on the walls, ceiling, and equipment, which can cause the installation to break down. Moreover, it is not pleasant for the staff to work with the refrigeration running. In order to counter this effect, a door contact shall be installed on the outside to shut down the refrigeration for a given time (e.g. 600 seconds, adjustable). Supplied under Refrigeration work package. 8.3.9 TEMPERATURE DISPLAY In accordance with the EN ISO 23953 standard, temperature display is required on each fixture in all countries, including outside Europe. The refrigeration engineer shall include in their bid digital display thermometers fitted to the front of the fixtures. The sales fixture temperature display shall correspond to a probe located in the air extract, except for freezer cabinets with doors, where the probe will be within the interior space. The extract probe shall be positioned in the least-favourable location in the fixture. Under no circumstances shall the probe be positioned too close to the refrigeration heat exchanger, which would cause a false reading if it became iced up. Ideally, it should be positioned in the extract grille at the front of the fixture. The Food Refrigeration work package shall check that the fixture supplier has correctly installed the display probes in the air extract.
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9 CENTRAL ELECTRICAL DISTRIBUTION CABINETS AND REFRIGERATION UNITS
9.1 GENERAL AND EQUIPMENT
These are the currently applicable legal requirements.
These electrical distribution cabinets shall be located in the plant room, in the proximity of the refrigeration units, and installed on the floor using a plinth provided for that purpose.
Electrical distribution cabinets for the retail refrigeration installation, divided in a carefully designed manner between the various systems: gas cooler, heat recovery, distribution of satellite units etc.
All the chiller and freezer units shall be equipped with a frequency converter on at least one compressor (two variable switches for those equipped with 6 No. compressors).
The electrical distribution cabinets shall include the necessary electrical equipment for protection, control and emergency operation applying to the use of frequency converters.
The automatic controllers shall also include the components needed for operation and control of the frequency converters.
Electrical connections to compressors supplied by frequency converter must utilise armoured cables of a section dependent upon the type of compressor and the maximum amperage set by the manufacturer.
Cabinets shall be equipped with at least 2 No. doors in order to limit the spatial impact when they are opened.
Cabinets shall be of sheet steel, totally enclosed, with a base frame (not a concrete base), divided into sections of 80 cm maximum width. Each section to have 1 No. single-leaf, waterproof door with an espagnolette lock and, on the inside of the doors, a pocket for diagrams and replacement fuses. The indicator lights may be mounted inside the cabinet, so long as they are visible and readable from outside (window).
Fuses and other control facilities shall be labelled. The distribution of connection terminals shall be agreed beforehand with the electrician.
In the supermarket context, these same cabinets shall contain the equipment for control, monitoring and supply of refrigeration output (central unit, gas cooler etc.) and the refrigeration unit outputs in relation to the unit they are supplied from (chiller storage units/main chiller unit).
Though contained within the same enclosure, a general circuit breaker shall protect the storage unit output distributor.
Electrical power for the whole installation shall be metered using an electricity meter with a 0/10 V output or Modbus serving all the installations. This shall be COUNTIS E40 type by SOCOMEC.
The electrical equipment as well as regulation of the refrigeration units are definitively
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specified by a diagram contained in the file.
This diagram constitutes the minimum for equipment and regulators to be contained in the electrical cabinets.
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The electrical diagram shall be drawn with current off, the switches being in the "cooling" position. All electrical diagrams shall be spontaneously submitted to the Owner before installation. The neutral earthing schemes shall be: TN neutral, TT or unearthed neutral. The short-circuit currents (SCC) shall be as follows:
Supermarket smaller than than 2500 m²: 15KA
Supermarket larger than 2500 m²: 20 Ka.
Hypermarket: 25Ka The electrical distribution panel shall include: – 2 No. sockets, – lighting system, – thermostat-controlled ventilation system as shown in the drawing below:
Natural ventilation
Separate rack sections on the electrical distribution panel. Mechanical ventilation
Example of electrical cabinet ventilation
Aluminium or steel sheet cabinets, totally enclosed, with a 10 cm plinth, splash-protected according to current Standards. The inside of doors shall have a fitting to hold diagrams.
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A transparent, Plexiglass covering shall be fitted behind the doors and suitably divided. The control and signage devices shall be integrated into the door and be covered on the inside face with a safety contact device. The signage devices shall be located within the cabinet insofar as the special windows in the cabinet door enable easy reading and visibility. Safety and control devices as well as equipment shall be durably labelled. The layout of connection terminals shall be arranged beforehand with the competent electricity company. Each control cabinet shall be equipped with a main switch with latch. Waterproofing of the cable ducts shall be checked by the service provider after completion. The control cabinets shall be constructed and installed in such a way that the doors can be freely opened and complying with the requirements of the country concerned with regard to the minimum space between the control cabinet and components and with regard to the minimum escape route that shall not be obstructed. The control cabinet shall have clear marking and inscriptions compliant with the electrical engineer's instructions. The main circuit breaker shall be labelled with the plant room number and the name/description of the control cabinet containing the supply fuse. A main switch shall be provided on the front of the control cabinet for each main feed (heavy current). The control devices, control safety devices, operating switches, heating, defrost heating, ventilator fans, timers, signal lights, terminals etc. shall also be durably marked with clear text and location numbers. The compressors must be restarted in stages after an emergency stop or any other fault. Moreover, the multiplex control shall be equipped to limit current peaks to the compressors, with regard to local conditions. All operating states (e.g. heat recovery operation etc.) shall be clearly, visibly indicated. Fault messages shall be indicated by a flashing light until the fault is resolved. An indicator lamp shall be installed to all signage displays. All the alarm displays shall have automatic UPS and a reset button. Regulations applying to electrical installations and control installations must be complied with. All major safety-related alarms shall be operated in a closed circuit with no electrical current (phase monitoring). Transmission of alarm signals shall be supported by an inverter. The refrigeration contractor shall deliver install and test it and maintain it. Frequency switches shall be mounted on a wall, outside the electrical control cabinets. The requirement for sine filters for the frequency controllers shall be determined by the refrigeration contractor.
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The switch being in the STOP position shall cut out the power and control circuit for the energy-consuming device concerned. Unless required by local law, it is not necessary to install isolation switches on the compressors once the electrical control cabinet is located within visual range of the energy-consuming device concerned. Temperature fault alarms shall be indicated on the corresponding group alarm systems. There shall be three indicator lights on the electrical cabinet doors:
Power on: white/yellow,
Fault: red,
Unit operated manually: orange. The front of the cabinet shall also include the emergency-stop, mushroom-head button, wired in parallel with that situated at the plant room entrance. 1 No. AUTO/STOP/MANUAL manual switch shall be provided for: – each compressor, pump, gas cooler fans; – the plant room ventilation control, linked to the R744 monitoring system. Operating hours metering shall be provided for: – each compressor, – all gas cooler fans, – emergency mains-water cooling (if available), – gas cooler atomising (if available). A meter to register the number of activations per day shall be provided for: – each compressor, The following indicators are mandatory: – per compressor operating, overload (thermal), coil (thermal resistor), high pressure, oil pressure hot gas.
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The following indicators are mandatory: – per system low pressure, high pressure, R744 alarm level, CO2 gas leak: plant room, CO2 gas leak: adjoining premises, CO2 gas leak: store, CO2 gas leak: cold stores and freezer rooms, emergency mains-water cooling (if available), electronic control; – plant room high-temperature – heat recovery positive operation for sanitary hot water, operation for heating system hot water (if available); – temperature alarm all refrigeration points; –group alarm temperature alarm on voltage-free switch. The temperature and technical fault alarms shall be separate from the general alarms. The number of times the compressors are switched on and off should be limited to a maximum of six an hour. No other energy-consuming device, of any type whatsoever, may be connected to the safety installations is not permitted. Switches that can be easily manipulated shall be installed to the various electrical circuits. The electrical diagram shall show the system disconnected from the power source, it being understood that the switching contacts shall be drawn in the "refrigeration" position. All electrical diagrams shall be presented to the Project Owner or specialist planner before being distributed, without this having to be specifically requested. The electrical diagrams shall be the property of Carrefour. The files shall be presented to Carrefour in, at least, .pdf and .dwg formats. If other formats are used, the corresponding software shall be submitted with them. 9.1.1 CHILLER AND FREEZER REFRIGERATED UNIT POWER OUTPUTS There shall be as many refrigerated unit outputs as there are regulators (see furnishing and cold store equipment table). These outputs shall be of the bipolar circuit breaker type with neutral cut-out. The selection curve shall be a function of the length, the cable section and the current drawn. NB. These cabinets only contain outputs, distribution and regulation shall be effected at the units and cold stores. This is with the exception of refrigeration plant room and refrigeration unit cooling.
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9.1.2 EQUIPMENT
Example of electrical control cabinet for refrigeration blocks and booster (with removable, hinged door leaves)
– Panel comprising multiplex cabling for all components on the booster or chiller
installation. A main circuit breaker for supply to the whole installation. Power control cabinet by booster or chiller unit operation: – Control and regulation of chiller and freezer installation according to suction
pressure; – Raising the evaporation temperature of the chiller and freezer installation
according to the store temperature and humidity as well as day/night operation; – All necessary control, monitoring, display and data input modules for the chiller
and freezer installation; – 1 No. chiller installation, hot gas temperature sensor; – 1 No. freezer installation, hot gas temperature sensor; – 1 No. hot gas temperature sensor, post heat recovery for sanitary hot water; – 1 No. hot gas temperature sensor, post heat recovery for heating system hot
water (if available); – 1 No overheat temperature sensor to gas cooler outlet conduit, for flash-gas; – 2 No. overheat temperature sensors for inlet and outlet flash-gas – 2 No. temperature sensors to liquid inlet and outlet of liquid sub-cooler; – 1 No. temperature sensor for monitoring chiller suction gas prior to integration of
freezers; – 1 No. temperature sensor for monitoring chiller suction gas after integration of
freezers; – 1 No. temperature sensor for monitoring chiller suction gas after integration of
flash-gas; – 1 No. temperature sensor for monitoring suction gas for the chiller suction
collector; – 1 No. temperature sensor for monitoring suction gas for the freezer suction
collector; – 6 No. reserve temperature sensors; – all modules required for temperature data input; – regulation of refrigeration units and liquid sub-cooler; – Main module with control timer, including grouping and clear signage of operation and
fault messages.
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Full regulation of gas cooler: – High pressure regulation according to external temperature or temperature of the gas
cooler outlet for optimum production under subcritical and transcritical operation, including control of HP valve regulation;
– Offsetting the high pressure setpoint in heat recovery operation (if applicable); – Regulating the high pressure emergency schedule; – Direction, continuous control and monitoring of the gas cooler fans according to the gas
cooler outlet temperature and the external temperature; – 1 No. external air temperature sensor; – Setting the minimum and maximum high-pressure and outlet temperature for the gas
cooler; – Regulating atomising as well as draining down if not used (if available); – Regulation of average temperature in relation to a configurable setpoint value, including
control of the bypass valve; – Control of high-pressure (HP) valve for average, minimum and maximum pressures; – Remote monitoring of all settings and measurement values as well as the setpoint value; – Pressure recorders for: chiller installation low pressure (LP), freezer installation LP,
average pressure (AP) and HP, including manual cut-off valves; – All necessary control, monitoring, display and data entry modules; – Temperature sensor at gas cooler outlet; – All modules required for operation of valve adjustments and status monitoring; – All logical links for safe functioning of the installation in compliance with regulations
(valve closing, compressor shut off etc.); – Emergency cut out for refrigeration installations inside and outside the plant room (press
button); – Security, control and regulation of gas cooling fans according to external temperature; – Security, distribution and control (interfaces) of heat recovery, sanitary hot water and
heating as well as logical links with the outlet temperature. Additional measurement and display of inlet and outlet water temperatures;
– Switch for setpoint value changeover for heating hot water recovery and signalling the emergency functioning on the remote monitoring system (if available);
– All interfaces for heat recovery for other systems; – Monitoring the refrigerant level; – Incorporating the day/night store lighting control. – All operating and fault indicator panels for: – Display for sanitary hot water recovery, Booster 1, Level 1; – Display for sanitary hot water recovery, supplementary electric heating / post-heating in
operation; – Various displays for heating system hot water recovery (if available); – Pre-alarm display/main alarm refrigerant level low; – Pre-alarm display/main alarm refrigerant level high; – Gas cooler fault display.
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– High pressure regulation fault display. – Emergency-water operation display. – Display as Priority 1, for emergency switching of sanitary hot water and heating system
heat recovery, alarm interval one minute (adjustable). – Display of all pressures, temperatures, valve position signals and turning speeds, as well
as operating status and fault messages on the remote monitoring system. – Price for complete installation and cabling of power control cabinet. – Complete cabling between power control cabinet and booster. – Cablequick cable entry plates, or equivalent, for water-tightness of control cabinet. Complete delivery of control cabinet, cooler and freezer refrigerator units. – Main cold power supply with separate outputs to booster installations power control
cabinets. – 1 No. kWh meter according to measurement design, calibrated and sealed for the main
power supply, transformer ratio (calculation factor for meter reading) on a clearly visible, engraved plate on the meter with M-Bus connection.
– All necessary control, monitoring and data entry modules. – Distribution and securing of all refrigeration units – Pressure sensors for electronic expansion valves, with a 1/4 inch shut-off valve for the
refrigeration chiller units. – Distribution and securing of plant room cooling. – Distribution and securing of all glass door freezer cabinets, freezer rooms, ice machines
and fermentation chambers. – Necessary pressure sensors for electronic expansion valves, with a 1/4 inch shut-off
valve for refrigeration freezer units. – Regulation of heating for frames of all glass door freezer cabinets and for evaporation
pressure according to the dew point. – Indication of door position for each cold room and freezer room "door open" with Alarm
Priority 2 (delivery of door contacts: refrigeration work package). Three-minute timing (adjustable).
– Direction of refrigerant gas leak monitoring in plant room. – Voltage-free switch for R744 gas alarm in plant room (230V/13A). – Voltage-free switch for Priority 1 (technical) fault signalling. – Starting up air extract ventilation in and outside the plant room.
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– Direction of R744 refrigerant gas leak monitoring in the adjacent premises; – Voltage-free R744 gas alarm switch in the adjacent premises (230V/13A); – Voltage-free switch for Priority 1 (technical) fault signalling for each of the adjoining plant
room; – Direction of R744 refrigerant gas monitoring on sales floor; – Voltage-free switch for R744 gas alarm on sales floor (230V/13A); – Voltage-free switch for Priority 1 (technical) fault signalling for each detector on sales
floor. - All operating and fault indicator panels required for: – Indicating R744 gas leak in the plant room; – Ventilation and air extraction in rooms with equipment in operation; – Indicating R744 gas leak on sales floor (for each gas detector); – Indication of R744 gas leak in adjoining premises (for each of the premises); – Signalling door position for each cold room and freezer room with Alarm Priority 2 for
"door open" (delivery of door contacts: refrigeration work package). Five-minute timing (adjustable);
– Day/night operation display; – 2 No. voltage-free switches to indicate Priority 1 faults (1 x temperature – 1 x technical);
– Voltage-free switch for CO2 alarm for each cold room and freezer room (230V/13A); – Voltage-free switch for trapped person alarm for each freezer room (230V/13A); – Treatment of the system / Electrical diagram and commissioning; – Schematic drawing / Visualisation of store;
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Example: visualisation of store
Cold room and freezer cabinets
Example: schematic drawing
– Price for complete installation and cabling of refrigeration units cabinet; – Complete cabling between the cabinet and refrigeration units; – Attendance at progress meetings for clarification of interfacing; – Cablequick cable entry plates, or equivalent, for control cabinet water-tightness. – If this is not provided for on the low voltage master distribution board, overload
protection shall be provided. It shall be ensured that the protection and the conductor are as close together as possible.
– Interface with the building management system compliant with Section 11.4.
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10. REMOTE MONITORING
10.1 GENERAL Delivery and commissioning an alarm system COMPRISING: A central unit made up of a central multi-gate processor (with data backup), multiplex and modem, mounted in the electrical cabinet, inclusive of operating software and commissioning. For monitoring purposes, a check shall be made of all de-superheat or condensation and evaporation temperatures for the cooler and freezer system. Both pressures and merchandise temperatures shall be checked. The alarm must be able to operate even during a power outage. Backup is provided by means of an uninterruptible power supply (UPS), that shall be delivered by the refrigeration contractor. All necessary components for the proper functioning of the remote management system shall be delivered by the refrigeration contractor. Installation of software and integration of the parallel alarm system connected to the Project Owner's control centre. Delivery and installation data to the specialist contractor. During the guarantee period, a complete remote monitoring and data storage service shall be provided by the refrigeration contractor (including linkage and connection costs). The contractor shall, at all times and upon request by the Project Owner, be able to transmit installation data. Moreover, the contractor shall supply the client and the specialist planner with all things required for access to the remote management system in read-only format. Control and alarm system tests:
Tests of temperature, technical and person alarms and of the linkage between these and the building's Measurement Control and Adjustment (MCR) system, in collaboration with other trades.
Testing lighting and ventilator fan cut-out power supply in the freezer compartments, to be conducted with the electrician.
Testing heating, ventilation and sanitary facilities connections with the contractors concerned.
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10.2 DIAGRAM OF REMOTE DATA MONITORING
Internet connection (e.g. TCP/IP) Fixed interface connection (e.g. RS 232)
Store No.1 Store No.2 Store No.3 Store No.4 Store No.
Firewall
Firewall
Danfoss Server
Eckelmann Server
Wum Server
… Server
Contractor 1 Contractor 2 Contractor 3 Contractor 4
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11. TREATMENT OF ALARMS 11.1 TECHNICAL ALARMS
The refrigeration contractor shall ensure that all necessary alarms are generated by the remote monitoring system in order to determine action to be taken or possible causes. Various alarm situations are listed below, showing the priority of each. This list is not exhaustive. It is essential that the priorities are observed, save in the event that the Project Manager demands otherwise. Component Alarm Priority 1 Priority 2 Priority 3
Compressor High pressure X
Low pressure X
Oil level X
Oil pressure X
Motor X
Frequency regulator compressor fault X
Gas cooler Motor fans X
Regulation fault X
Sensor fault X
Gas outlet temperature too high/low X
Systems Each gas detection alarm, individually X
Pre-alarm: low refrigerant level X
Main alarm: low refrigerant level X
Alarm: refrigerant level too high X
Regulation sensor fault X
Display sensor fault X
Defective pressure sensor X
Suction gas temperature too high/low X
Hot gas temperature too high/low X
Power outage fault X
Safety low-pressure X
Safety high-pressure X
Safety average pressure X
HP regulating valve fault X
Flash-gas regulating valve fault X
Freezer installation, gas de-superheater dysfunction
X
Emergency stop button activated X
Emergency cooling in operation X
Refrigeration pressure maintenance unit fault
X
Operation of refrigeration unit and pressure maintenance
X
UPS fault X
Sanitary hot water recovery
Heat recovery in operation X
Safety thermostat X
Heat recovery pump fault X
Chiller and freezer refrigeration units
Too hot X
Too cold X
Defrost time exceeded X
Sensor fault X
Each gas detection alarm, individually X
Trapped person alarm X
Negative logic physical contacts (power on in normal operation and cut off in the event of a fault). Malfunctions are indicated by means of an alarm contact as group faults:
Priority 1: requiring immediate action (group technical and temperature fault);
Priority 2: requiring action within three working days (group technical and temperature
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fault);
Priority 3: not requiring immediate action, status indicators, not communicated externally.
Transmission of alarms is mandatory from the time that an item of equipment is made available to the operator (cold rooms and glass-door display cabinets).
11.2 MANAGEMENT OF ALARMS The two gateway fault switches are connected to an alarm box (see diagram) installed in the proximity of the remote monitoring control centre. The alarm box, supplied and installed under this work package, enables:
the gateway fault switches to be kept open for between two and 10 minutes (signalling new faults);
automatic maintenance of fault status until cancelled by use of a push button on the front of the box (store staff taking account of the fault).
signalling non-cancelled faults with two red indicator lights;
signalling the occurrence of a new fault with a buzzer. NB. The refrigeration contractor performing the installation shall check with the store's remote monitoring company that alarms are being correctly transmitted. All equipment transferred for operation shall be fitted with alarms. In default of this, the contractor for this work package shall be held responsible for loss of merchandise in affected equipment.
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11.3 ACTION PROCEDURE – RESPONSE TO ALARMS The company providing standby service shall be jointly specified by the refrigeration contractor and the Project Owner. The following procedure is specified:
Daytime, during store opening hours Night-time, outside store opening hours
Alarm/Fault via remote monitoring
Alarm/Fault via remote
monitoring
Fault/ Message from store
Ala
rms
/
Fa
ult
s
Ala
rms/
Fa
ult
s
Refrigeration contractor Refrigeration contractor
Action by the remote
monitoring service
Direct action on site
Action by the remote
monitoring service
Direct action on site
Access procedure Clearing the fault
Action sheet
Information to technical manager
Clearing the fault
Action sheet
Information to technical manager
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11.4 EMS SYSTEM INTERFACES The following interfaces shall be made available to Carrefour by the refrigeration contractor by means of an RS-232 interface: – Automatic controller, virtual watchdog; – Chiller cabinets temperature; – Freezer cabinets temperature; – HP, LP overview: chiller compressors; – HP, LP overview: freezer compressors; – Refrigerant fluid level low; – Communications faults: units and cold/freezer rooms.
12. INSTALLATION ACCEPTANCE CONDITIONS Each country's specific regulations shall be taken into account. All additional duties arising from other Standards shall be taken into account during commissioning and preparing for commissioning.
12.1 PRIOR INSPECTION The contractor responsible for refrigeration shall submit all components or the entire refrigeration installation to the following pre-commissioning inspections:
Pressure strength testing in compliance with Standard EN-378-2: 2008, Section 6.3.3;
Testing leak tightness in compliance with the Standard EN378-2: 2008, Section 6.3.4;;
Operational inspection of pressure-limiting control and safety devices;
Compliance inspection of the total installation in accordance with Standard EN378-2: 2008, Section 6.3.5;
Markings and documentation of components in accordance with Standard EN378-2: 2008, Section 6.4;
Training of staff responsible for use in compliance with Standard EN378-2: 2008, Section 4.2;
Performing an external visual inspection of the total installation in compliance with Standard EN378-2: 2008 (Annex G).
All inspection results shall be recorded.
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12.2 MOISTURE – VACUUM EVACUATION – LEAK-TIGHTNESS TEST* *According to current local legislation
Both R744 and Polyol Ester fluid are very moisture sensitive. If this precaution is not taken, hydrofluoric acid may be formed, considerably reducing the service life of the installation (especially compressors).. This operation shall be carried out to the entire installation. If particular site conditions obtain, pipework shall be isolated segment by segment. This work package shall apply the same method to each segment as to the entire installation. The various segments shall be commissioned in such a way that introduction of air into the circuit is prevented. These vacuum evacuations shall be carried out once all soldering and connections have been carried out to the part concerned. The vacuum evacuation shall be carried out:
with a vacuum pump: in two stages, with sufficient capacity to obtain a final vacuum of 0.03 mbar (3 Pa) suitable for R744 fluid containing Polyol Ester oil;
using R744-compatible hoses (lined with nylon or polyamid) of sufficient diameter to limit loss of pressure.
A vacuum meter, located in the proximity of or on the installation, shall be used to monitor pressure. Under no circumstances shall vacuum pressure be measured in the proximity of the pump (measurement error due to pressure loss in the hoses). The vacuum shall be maintained for 24 hours (pump stopped) in the first instance. Changes to the vacuum shall be measured each hour. The test shall only be deemed successful if the pressure rise does not exceed 0.3 mbar. The refrigeration plant being delivered pressurised by dehydrated nitrogen, the plant isolation valves shall remain closed during the first vacuum evacuation. Once the vacuum has been maintained 24 hours without a pressure rise greater than 0.3 mbar, the vacuum shall be released with dehydrated nitrogen in order to absorb residual moisture. The unit valves shall, thus, be open. The vacuum shall be released at least once with the nitrogen and recreated once more. The vacuum shall, thus, be created a second and final time over the whole installation (the circuit plus the central refrigeration unit), to the same levels as the first time. Following these two operations and after the installation has been in operation for 72 hours, the residual moisture, which should not exceed 40 ppm, shall be measured by the contractor for this work package. This measurement shall be clearly shown in the oil sample analysis required. After commissioning the refrigeration installation, and oil test is required and shall be the subject of a written confirmation during technical acceptance of the installations.
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12.3 COMMISSIONING
12.3.1 GENERAL The finished installations shall be brought into operation as soon as possible.
The contractor shall the proceed with the commissioning, safety and alarm operations described in the "Acceptance conditions" Section.
The contractor shall produce written instructions for both routine monitoring and checks of proper functioning.
Electrical installations insulation check.
Programming and adjusting the automatic controller regulators.
All commissioning of refrigeration equipment shall be carried out by the equipment manufacturer.
The contractor shall supply the necessary calibrated measuring instruments to take accurate readings and these instruments shall remain its property.
The schedule of checks of performance, temperature compliance, hygrometry etc. shall be carried out and reported upon in the acceptance report according to the terms of the "Acceptance conditions" Section.
The following points, set out between Section 12.3.2 and Section 12.3.9, are only a partial extract of the relevant points. Checks and commissioning shall be carried out according to Standard EN-378 and the pressurised equipment regulations, as well as in relation to local conditions.
12.3.2 PRIOR TO COMMISSIONING
Check the safety valves degassing device.
Check the position of the safety valves for the various sectors.
Check the markings/labelling on the safety valves (regulating pressure, rated decompression power, flow rates and diameter of opening).
Check positioning of gas detectors. 12.3.3 PREPARATION FOR COMMISSIONING
Check operation of alarms.
Check operation of gas detection.
Check and re-tighten all terminals, protective systems, relays etc.
Create vacuum.
Air extraction to plant room operational.
Verify leak tightness of plant room.
Remote monitoring operational. 12.3.4 COMMISSIONING
Regulation and testing of emergency circuits.
Regulation and checking all safety devices.
Checking temperatures, regulation of expansion valves.
Measurement of air and hydraulic flows as well as balancing them.
Measurement of pressure loss to the most vulnerable refrigerant circuits, under maximum load.
Measurement of electrical current drawn.
Regulation of calibration and reference points of probes and other sensors.
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Regulation of thermo relays after checking their proper functioning.
Checking alarm and regulation safety sequences.
Behaviour of various materials.
Setting up cold rooms (temperature and hygrometry).
Measurement of speed of refrigeration for food items on the premises.
Defrosting tests.
Checking safety devices and automatic controllers.
Measurement of power consumed by compressors and motors using clamp-on ammeter.
Certification of contractual temperatures by furnishing recorded temperature curve.
Commissioning refrigeration unit and pressure maintenance, with all necessary tests (with emergency generator).
12.3.5 COMMISSIONING HEAT RECOVERY FOR SANITARY HOT WATER
Check that all connections to the boiler are present and sealed.
Check that the system has been correctly installed and that all safety devices are in place (safety pressure valves, pressure switches, sensors etc.)
Check boiler filled.
Check intermediate circuit filled.
Calibration of pressure gauges and thermometers
Check that intermediate circuit expansion vessel correctly commissioned (initial pressure etc.)
Safety sequence testing
Checking the siting of probes (provide all sensors with conductive paste, aluminium strip and insulation).
Open all valves and frames.
Switch on the intermediate pump for the circuit.
Start up the pump.
Set regulation mode to Δp constant.
Check the flow volume and, in all events, reduce the flow if there is a major discrepancy.
Regulate the settings according to Section 7.7.1.
Check the 0-10 V signal to see whether the pump is operating with the signal.
Test the fault contact.
Commission the three-way valve in the charging circuit.
Calibrate the valve.
Check regulation against a constant/linear percentage.
Test starting and stopping contacts.
Test boiler load.
Commission the heat recovery system.
Check safety devices once more.
Complete the commissioning report.
12.3.6 FULL TRAINING FOR STORE STAFF Before commissioning, the contractor responsible for the refrigeration installation is required to provide full instruction for sales staff as well as technical personnel. For this purpose, the attached "Instruction form" document should be completed and signed off by the relevant departments at the end of training. The document shall be submitted at the same time as the service documents.
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12.3.7 DRAFTING THE COMMISSIONING REPORT In compliance with Standard EN-378, the refrigeration contractor is required to document the settings. To this effect, a commissioning report shall be drafted with all settings important to the safety of the installation. Commissioning protocols shall be submitted before technical acceptance. 12.3.8 AFTER COMMISSIONING Refrigerant fluid and oil The refrigeration work package contractor is required to supply the fluids necessary for operation of the refrigeration installations: refrigerant fluid, non-freezing oil etc. The contractor shall provide an analysis of the oil before acceptance of the installations, another analysis one year after commissioning and an analysis two years after commissioning. The contractor must supply the Project Owner, before final acceptance of the installations, with analyses of the oil of each installation. These oil analyses must show the moisture levels, contamination levels of the circuit by metals and the acid levels. These analyses shall be carried out by a competent laboratory and shall be accompanied by comments regarding the residual water content (max. 10 ppm at evaporation -30° C). Thus, three analyses shall be furnished. In the event that the installations are not accepted due to non-compliance, or that they are accepted subject to reservations, the contractor shall provide additional products, after the modifications that he has to make to the installations. This work package is, thus, responsible for the additional supply of refrigerant fluid and oil for the installations. 12.3.9 PROVISION OF FINAL DOCUMENTS
Analysis of intermediate circuit sanitary hot water heat recovery water after 1st year of operation;
Analysis of intermediate circuit sanitary hot water heat recovery water after 2nd year of operation;
Analysis of intermediate circuit heating system heat recovery water after 1st year of operation;
Analysis of intermediate circuit heating system heat recovery water after 2nd year of operation;
Training report;
Commissioning report;
Oil analysis prior to technical acceptance;
Oil analysis after 1st year of operation;
Oil analysis after 2nd year of operation;
Maintenance documents;
Refrigeration assembly specification. 12.3.10 CHECKING REMOTE TRANSMISSION OF ALARMS The contractor for this work package shall furnish a document certifying that each alarm is transmitted to the remote monitoring company named in the protocol to this document. Faults shall not be checked using a summary of faults, but shall each be independently checked.
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12.3.11 MARKING After official commissioning, technical acceptance or quality checking shall be undertaken with the Project Owner or their consulting engineers. Two weeks in advance, the company shall inform the Project Owner or their consulting engineers, in writing, of their availability for the acceptance meeting (by sending the "Ready for acceptance" declaration form, and instructions for installation of the technical refrigeration section). This work package is responsible for completes labelling of its installations and, in particular:
Labelling service valves, compressors and all safety and emergency devices;
Installation of a general installation plan, in the plant room. This plan shall be mounted on a board and protected with plastic film. It shall show the marking of regulator devices for all cold rooms, display cabinets and other installed equipment. This plan shall set up clear references between the terms used for automated temperature recording of the refrigeration units and the physical units As shown on the plan. E.g. if the self-service meat display unit is coded "48", the number "48" shall be shown on the plan;
Labelling all refrigeration units, showing the number of defrostings, the regulatory temperature for the unit, the unit's reference in the temperature recording system. E.g., if the self-service meat display unit is coded "48" on the recording system, the number "48" shall be marked on the unit's label.
12.4 DOCUMENTATION* *According to current local legislation
12.4.1 AS BUILT FILE The following As Built documents must be submitted to the Project Owner or their consulting engineers at least two (2) weeks before acceptance and one (1) copy in paper form (in a binder): 1. Acceptance protocols 2 Display on installations:
– a list of refrigerated units showing temperature and cooling power; – booster configuration showing main technical data; – heat exchanger information; – gas cooler information; – liquid cooler information; – de-superheater information; – compressor information; - store layout drawing; – safety valves design calculation; – all design calculations other than those furnished by the thermal energy audit
(TEA). 3. Functional description notice of the installation and declarations in compliance with
Standard EN378. 4. Commissioning and refrigeration output test protocols, showing settings, pressure tests
and inspection for leakproofness of the installation (according to current legislation). 5. Commissioning and test protocol for refrigeration points, showing settings (according to
current legislation).
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6. Refrigeration and hydraulic diagram on a single plan: one copy, under glass, mounted on the wall in the plant room;
7. Electrical diagram including IT equipment for programming automated systems; 8. Temperature recording chart; 9. Maintenance notice showing periodic inspections and maintenance work to be carried
out each day, each week, etc.; 10. Service notice for particular cases (Danfoss, Bitzer, Güntner, speed regulators etc.); 11. Coordination plans; 12. Cold room plans; 13. List of spare parts for the main components showing the make, type and reference
number and a suppliers address list; 14. Risk analysis, compliance and instructional protocols; 15. Certificate from the authorised body, confirming collection for recycling of used
refrigerant fluids collected during the works. Plan to be installed on site in the refrigeration plant room:
Refrigeration diagram printed on a display panel [Artopex].
On-site store layout plan printed on a display panel. No acceptance shall take place without the above-mentioned documents. Technical acceptance shall not take place unless the premises are absolutely clean. No later than acceptance, operating staff shall be instructed in the appropriate use and upkeep of the installations. After validation, three copies of the completed works folder must be submitted on paper, and one copy on computer media. The following shall be added to the computer media:
A copy, in Excel format, of all regulator settings of the refrigeration installation.
The acceptance file for the refrigeration installations.
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12.4.2 MISCELLANEOUS DOCUMENTS The refrigeration equipment work package contractor shall also furnish:
A plasticised refrigeration diagram for display in the plant room;
Compliance reports for installed equipment with regard to current Standards;
The maintenance and service record book, enabling reference to the equipment service history (faults, actions taken etc.).
The operation and maintenance handbook, including emergency measures.
The contractual documentation.
12.5 MARKING DESIGN 12.5.1 GENERAL The requirements of Standard EN 2405 or local instructions must be observed. Numbering of floors: RL = Roof Level 1F = 1st floor MF = Mezzanine floor GF = Ground floor 1B = 1st basement level Colour:
Colour Colour of background/panel
Colour of inscription
CR Commercial refrigeration Black RAL 9005 White
S Sanitary installations Green RAL 6024 White
H Heating installations Red RAL 3020 White
Positioning and description of the installation: The refrigeration installations shall be marked according to the installation numbering plan. Pos. A = Booster refrigeration chiller units Pos. A = Booster refrigeration freezer units Pos. B = Booster or chiller installation refrigeration chiller units Pos. B = Booster refrigeration freezer units Pos. C = Booster or chiller installation refrigeration chiller units Pos. C = Booster refrigeration freezer units Pos. D = Booster or chiller installation refrigeration chiller units Pos. D = Booster refrigeration freezer units Example of positioning: Pos. A1.1 Self-service, refrigerated, glass-door display cabinet: fruit and vegetables (Booster A) Pos. B1.1 Self-service freezer cabinet (Booster A) Pos. C1.1 Self-service, refrigerated, glass door display cabinet: meat (Booster A)
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12.5.2 DESCRIPTION OF ELECTRICAL CONTROL CABINETS In compliance with the electrical planning instructions. 12.5.3 DESCRIPTION OF REFRIGERATION INSTALLATION
12.5.3.1 Conduits
– Yellow colour adhesive sign
– Medium type (Green = liquid conduit, Blue = suction conduit, Red = hot gas conduit)
– Type of fluid and description of installation to be added
– Dimensions according to the above instructions
Label dimensions a1 x b1
a2 b2 h
126 x 148 52 x 297
18 37
74 148
12,5 25
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12.5.3.2 Installation/Refrigerant agent – Black colour plastic label
– White colour, engraved inscription
– Dimensions according to the above instructions
- Type of mounting: rivets or screws
12.5.3.3 Compressor
– Black colour plastic label
– White colour, engraved inscription
– Dimensions according to the above instructions
- Type of mounting: rivets or screws
12.5.3.4 All components requiring electrical connection
– Black colour plastic label
– White colour, engraved inscription
– Dimensions according to the above instructions
– Type of mounting: with small chain or cable clip (not glued) fixed onto the electric cable
Booster R744 / CO2
Chiller refrigeration compressor 1
Freezer refrigeration compressor 3
Chiller refrigeration compressor 1
HP Pressure switch
Number on electrical diagram
Description of peripheral unit / description
Installation number/description
Electrical distribution panel description
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12.5.3.5 Refrigeration chiller/freezer cabinets – Black colour plastic label
– White colour, engraved inscription
– Dimensions according to the above instructions
- Type of mounting: rivets or screws
12.5.3.6 Adhesive label for defrosts
– White colour, self-adhesive, synthetic film label
– Black colour inscription
– Dimensions according to the above instructions
- Type of mounting: rivets or screws
12.5.4 SANITARY INSTALLATION DESCRIPTION In compliance with the sanitary installation planning instructions. 12.5.5 HEATING DESCRIPTION In compliance with the heating installation planning instructions.
Defrosting timetables
Time 00 01 02 03 04 05 06 07 08 09 10 11
Time 12 13 14 15 16 17 18 19 20 21 22 23
Pos. ______ Target temperature ______ Name ______ Date __/__/____ Signature _________________
Installation number/description
Description of refrigeration cabinet
Chiller refrigeration booster
Self-service, glass-door display cabinet: cheese
Position No.
Electrical diagram No.
Electrical distribution panel description
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13. WARRANTY Warranty: comprehensive warranty of the entire installation for two years; five years for hidden defects. This two-year, on-site warranty is specific to and assignable with the store and only concerns installations modified during the works. The Project Owner shall retain responsibility for water and electricity consumed. Overall upkeep, maintenance, fault repair, cleaning, optimising energy performance and remote monitoring of the refrigeration installations shall be the subject of a separate proposal according to the following documents: – Framework contract for provision of comprehensive maintenance services for CO2
refrigeration installations; – Comprehensive service contact for CO2 refrigeration installations; – Worksheets for maintenance tasks on CO2 installations A bid must be attached to this food products refrigeration work package, based on the above-mentioned documents.
14. SERVICES NOT INCLUDED IN THE WORK PACKAGE / SCOPE OF SERVICES
14.1 SCOPE OF SERVICES 14.1.1 WORKS INCLUDED IN THE FOOD PRODUCTS REFRIGERATION WORK PACKAGE The contractor for this work package is responsible for provision of the following services and installations, this list not being exhaustive. 1) Detailed design of the installations together with:
Detailed design notes;
Complete AutoCAD execution drawings of all installations proposed;
Drawings of boxing out and plinths with indication of loads;
Operational diagrams;
Operational and regulatory analyses;
Electrical and regulatory diagrams;
Drawings and files in relation to fire safety;
Drainage plan;
List of installed equipment with technical documents and manufacturers' references;
Test and performance record book, including test certificates, covering all plant and installed equipment;
Furnishing test reports and reports on fire resistance of materials used;
Maintenance notice of operational and safety devices;
Furnishing all these documents to the Owner and to the supervising body according to site requirements.
2) Manufacture, provision, transport to site, provisional storage and installation of equipment;
3) Setting up and removing all lifting plant, bracing equipment and scaffolding required for handling.
4) Labour required for various drain downs and fillings as the works progress. 5) Tests and trials, commissioning and regulating the whole installation.
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6) Measurements provided with tests, such as temperatures, pressures, electrical current drawn, measurement devices being provided by the contractor for this work package. With a view to acceptance of the works, the contractor must proceed with programmes of measurements carried out on the premises by means of recorders (temperature, speed, flow, pressure etc.) on a sampling basis, according to the Project Owner's instructions.
The contractor shall be responsible for provision, leasing and setting up calibrated measurement apparatus and drafting reports in table form. These tables shall be attached to the in-house service file for the installation.
7) Participation in BMS tests. 8) Labelling and marketing all items of equipment and services installations, as well as
the various regulation and isolating devices. 9) General schematic outline diagrams: multicoloured, non-modifiable, plasticised. These
schematic diagrams shall be installed by the contractor for this work package in each plant room in the proximity of the electrical cabinet.
10) General cleaning upon completion of works, in addition to routine cleaning. 11) Services in connection with the conduct, supervision and maintenance of the
installations between the completion of works and their acceptance. 12) Training management and maintenance personnel (also see Section 14.7.2). 13) All documents shall be the property of Carrefour and must be sent to Carrefour in
electronic format.
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14.1.2 WORKS EXCLUDED FROM THE FOOD PRODUCTS REFRIGERATION WORK PACKAGE Works in connection with the Food Products Refrigeration work package that are not within the remit of the contractor of this work package, but that concern it, shall be designed and executed under its supervision.
The contractor shall furnish, in good time, to the trades concerned, all information, schematic diagrams and plans necessary for the said works.
The contractor shall confirm and specify or modify, with the prior agreement of the Project Manager, without, however, there being financial consequences for any work package covered in the draft call for tenders.
14.2 STRUCTURAL WORK PACKAGE 14.2.1 WORKS EXCLUDED FROM THE FOOD PRODUCTS REFRIGERATION WORK PACKAGE
Masonry plinths, blocks and bases for equipment supplied and installed under this work package;
Masonry ducts for vertical conduits.
Boxings out larger than 15 x 15 cm in the walls and concrete slab or in existing or new masonry.
Stopping up ducts to floors and walls after feeding through pipework. NB. Works not asked for in good time and that are not shown on the boxing out drawings shall be performed at the cost of the contractor of this work package. 14.2.2 WORKS REQUIRED BY THE FOOD PRODUCTS REFRIGERATION WORK PACKAGE
Design and implementation of boxings out, floor openings, plinths and structures necessary for this work package;
All holes, chases, cemented fixings, fixings necessary for the passage of pipework and assembly of equipment.
Restoration of fire rating to walls and floor slabs.
14.3 WATER-TIGHTNESS – ROOF COVERING WORK PACKAGE 14.3.1 WORKS EXCLUDED FROM THE FOOD PRODUCTS REFRIGERATION WORK PACKAGE
Sealing around protrusions to flat roof.
Water-tightness surveys of roof protrusions. 14.3.2 WORKS REQUIRED BY THE FOOD PRODUCTS REFRIGERATION WORK PACKAGE
Enclosures (covers or cladding). 14.3.3 WORKS REQUIRED BY THE FOOD PRODUCTS REFRIGERATION WORK PACKAGE
Supply of pipework supports to refrigeration display unit downpipes.
Supply of supports for horizontal pipework, both exposed and ducted.
Cladding vertical stacks/stanchions on refrigerated display units in lacquered steel sheeting.
14.4 PARTITIONS – PAINTING – FALSE CEILINGS WORK PACKAGE
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14.4.1 WORKS REQUIRED BY THE FOOD PRODUCTS REFRIGERATION WORK PACKAGE
Anti-rust paint to all metal parts implemented;
Painted finish to pipework in plant rooms;
Cutting out and drilling to partitions and false ceilings for pipework penetrations;
Painted finish to pipework.
Visual identification of services installations.
14.5 PLUMBING – SANITARY FACILITIES WORK PACKAGE 14.5.1 WORKS EXCLUDED FROM THE FOOD PRODUCTS REFRIGERATION WORK PACKAGE
Works for evacuation of evaporator condensates;
Tapping off, valve and water supply to rooftop tap. 14.5.2 WORKS REQUIRED BY THE FOOD PRODUCTS REFRIGERATION WORK PACKAGE
Condensate collectors up to connection points;
Positioning of collection points for compensate evacuation.
14.6 ELECTRICITY – HIGH-VOLTAGE 14.6.1 WORKS EXCLUDED FROM THE FOOD PRODUCTS REFRIGERATION WORK PACKAGE
Power supply to upper floor refrigeration plant room;
Power supply to automatic control enclosure circuit;
Power supply for lighting refrigerated display units including remote control from the refrigeration cabinet.
14.6.2 WORKS REQUIRED BY THE FOOD PRODUCTS REFRIGERATION WORK PACKAGE
Confirmation of requirements for power supply;
Connection of the entire installation from the upper floor refrigeration plant room;
Connection of lighting to refrigerated display units.
14.7 MISCELLANEOUS As well as the works and installations set out in the Best Practice document and the drawings, the overall lump sum price also includes, in a specific provision, costs in connection with execution of works and supply of goods and services with regard to:
Bringing the refrigeration into operation before opening of the store.
Conduct, supervision and maintenance until acceptance and opening of the store.
Training operational staff and providing As Built file. 14.7.1 CONDUCT – SUPERVISION – MAINTENANCE UNTIL ACCEPTANCE At completion of installation works of this work package, the contractor shall be required to conduct, supervise and maintain the installations in good operational order. Maintenance shall include all works and equipment according to the maintenance contract. 14.7.2 TRAINING OPERATIONAL STAFF AND PROVIDING AS BUILT FILE This work package is responsible in particular for:
Training in operation of installations, to take place prior to acceptance.
Furnishing 4 No. copies of a maintenance manual including, in addition, contact details of all suppliers, all plans and schematic diagrams as executed (see: Scope of Services).
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14.7.3 REFRIGERANT FLUIDS Implementation of refrigerants shall comply with the following regulations:
According to current legislation in the country concerned. 14.7.4 PRESSURISED EQUIPMENT
According to current legislation in the country concerned.
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