Modular Air-Cooled Screw Chiller - BT Malta · Modular Air-Cooled Screw Chiller (Modular Air-Cooled Screw Chiller is short) is a type of refrigerant ... water temperature for cooling

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Thank you for choosing Commercial Air Conditioners, please read thisowner’s manual carefully before operation and retain it for future reference.

Modular Air-Cooled Screw Chiller

Commercial Air ConditionersOwner's Manual

Contents

1 Summary ..................................................................................................... 12 Operation Instructions for the Display of the Controller ............................. 2

2.1 Brief Introduction to the Display .......................................................................... 22.2 Operation Instructions to the Display ................................................................... 2

3 Electric Principles ...................................................................................... 163.1 Connections for external control ....................................................................... 163.2 Wirings List ........................................................................................................ 163.3 Connection of units and external connection wires ............................................. 163.4 Connection among Modules ............................................................................... 173.5 Dial-up switch to main board ........................................................................... 17

4 Instruction to installation of unit ................................................................ 174.1 Inspection .......................................................................................................... 174.2 Outline and dimension of the unit ..................................................................... 204.3 Installation and maintenance space .................................................................... 234.4 Connection of water- pipe system ..................................................................... 23

5 Maintenance .............................................................................................. 255.1 Daily startup or stop of the unit ......................................................................... 255.2 Maintenance of the main parts .......................................................................... 255.3 Requirements to water and contaminant release ................................................ 255.4 Maintenance for lengthy shut down ................................................................. 255.5 Startup of the unit after lengthy shut down ...................................................... 265.6 Replacing components ...................................................................................... 265.7 Cooling system .................................................................................................. 265.8 Anti-freezing ....................................................................................................... 265.9 Other notifications .............................................................................................. 27

6 Trouble Shooting ........................................................................................ 287 Attachments ............................................................................................... 31


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1 Summary Modular Air-Cooled Screw Chiller (Modular Air-Cooled Screw Chiller is short) is a type of refrigerant

facility which supplies cooling water in summer as well as heating water in winter. It can be combined with the terminal units with air processing such as air-cooled unitary standing units and combined type units to be various types of large-scale and centralized air-conditioning system. This air-cooled design can avoid installing cooling tower and cooling water pump for users, so the units are especially suitable for water deficient regions. The units can be installed on the rooftop, ground outside and so on instead of being equipped with a special machine house. It can widely applied in new–built or reconstructed industry and civil-building project, such as hotels, apartments, restaurant, office building, shopping mall, theater, gymnasium, hospitals and so on, as well as supplies required cooling (heating) water for factories in technical process of producing, so it’s especially suitable for some special locations around where there are high-level requirements for noise and environments and boiler and cooling tower are difficult to install.

a. Modularization: The patented design of that any unitary module can be as master module, makes various emergencies easy. Each unitary module can be combined with another module with different capacity so that different units with different cooling capacity are formed in a wider application range. Balanced running of compressor extends the lifetime of unit. The compressor of each unitary module will be started one after another to ensure less attack to power network. The design of combination of modular makes the unit compact in size and configuration, convenient in delivery and installation.

b. High efficiency: The new generation of screw compresses with balanced load and high-efficiency and helical twin screw with nearly 100,000-hour lifetime can efficiently avoid leakage and improve the compressing efficiency. Combined with perfectly-matched refrigerant and reliable control technology, they can also make the units efficiently run at full load as well as at partial load.

c. High reliability: As a specialized air-conditioning company, this company has been engaging in technical improvement and innovation; it adopts perfect service parts, strict control on each manufacturing procedure and strict test to each ongoing product in performance to ensure quality and performance, moreover, reliable motor- cooling technology and oil return technology for refrigerant system ensure the compress running in well conditions.

d. Energy saving: With perfect design, the energy levels of each unitary module can be adjusted by 0-25-50-75-100%; in addition to it the combination of many unitary modules make the unloading capacity of unit fold increased, which totally matches the practical load. Because units running at partial load most of time, the energy consumption is much less than before.

e. Quiet running and long life: The double-shaft of the compressor is accurately located by axial direction and radial of rolling bearing to ensure even stress, quick compressing procedure without decentration and reciprocate, low pressure fluctuation, low vibration and reliable running of the compressor.

f. Long-distance monitoring: Adopting high-performance C Builder Software to program under Windows system and graphic means, the computer can clearly display running curve of the units. International universal 485 industrial buses are used for communication with the distance as long as 800m, which can connect and simultaneously monitor 255 units to form a monitoring network, furthermore, all the functions of manual controller owned by the unit can be displayed in the computer so that there is no necessary to monitor or control the units in computers’ house.

g. Environmental friendly refrigerant:The R134a,whose ODP(Ozone Depletion Potential) value is 0,is a environmental friendly refrigerant.It does no harm to Ozone complately, and its usufruct is unlimited.

h. Running in atrocious weather:Adopting multifarious atrocious weather,the units can reliably running in a large temperature scale,from 18 to 52 degrees centigrade.


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2 Operation Instructions for the Display of the Controller

2.1 Brief Introduction to the DisplayAs for the networking control to 1~8 modules, only one display is equipped for displaying the control

menus, receiving and displaying all kinds of parameters from the main board controller, setting the adjustable parameters, as well as sending the adjusted parameters back to the main board controller.

Control Panel of the Display:

① .“POWER” Indicating Lamp: the lamp shines when the display is energized.② .“ERROR” Indicating Lamp: the lamp flickers in the event of a fault.③ .“RUN” Indicating Lamp: the lamp shines when the display is turned on.④ .“ON/OFF”: switchover between the ON/OFF statuses of the unit. Under the OFF state, press it for

5 seconds to go to the ON state, and it is also available to go to the OFF state in the same way under the ON state. Besides, no continuous clicking is allowed.

⑤ .“MENU”: go to the Menu interface immediately by pressing this button at any condition.⑥ .“▲”: Move the cursor upward or leftward by pressing this button for selecting an option. When

modify some data, the value of the data can be increased also by pressing it. Additionally, pressing this key for much longer time can make the incremental change to the value of the data.

⑦ .“▼”: Move the cursor downward or rightward by pressing this key for selecting an option. When modify some data, the value of the data can be decreased also by pressing it. Additionally, pressing this button for much longer time can make the decremental change to the value of the data.

⑧ .“ENTER”: Confirm the option you want to select by pressing this key. Also, press this button to make the final confirmation to some changed parameters and then move the cursor away.

⑨ .“EXIT”: quit from the current operation by pressing this button.⑩ .“Status Column”: Where a brief indication is offered to tell the function of the current function key.

2.2 Operation Instructions to the Display

2.2.1 HomepageWhen the controller is power-on, the microcomputer will take several seconds for the self-examination


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and the LCD display will be like as follows:

00:00 Sat.2010-05-01

State：Cooling ON ON-OFF Mode：Manual

Module Qty：01 pcs Error：No

Anti-freezing：Yes Modbus：Yes

Press <MENU> to open menu interface. Menu

C/OSCREWUNIT

The date and time is displayed on the upper left, and in the middle is the status of the unit. When an alarm is raised for frequency protection or the unit is locked due to frequency protection, the display will back to the homepage and show up the alarm text which then can be canceled by pressing the “EXIT” button.When there is no any button operation on the wired controller in ten minutes, the display will automatically back to the homepage.

Remarks:About the State, apart from Cooling OFF, Cooling ON can also be displayed.The ON-OFF mode can be either manual or timing. Regarding the error status, if there is no any error, it

will be black lettering in white; if there is, it will be shaded in black.

00:00 Sat.2010-05-01

State：Cooling ON ON-OFF Mode：Manual

Module Qty：01 pcs Error：No

Anti-freezing：Yes Modbus：Yes

Press <MENU> to open menu interface. Menu

C/OSCREWUNIT

Under any condition, Pressing ON/OFF button can jump to the homepage. If it is the operation for startup, meanwhile a window will pop up to indicate “Please input password”. If it is the operation for OFF, the unit will be turned off directly without the popup of such a hint window. (It is not applicable in the condition of the remote shield).If the input passwords are correct, the unit will run normally, while if they are incorrect, a window will pop up to indicate “Wrong Password”. In this case, press ENTER or EXIT and then this window will disappear.


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2.2.2 Menu InterfaceUnder any condition, pressing MENU can go to the Menu interface, through which you can select the

option you want to control or view, as shown below.

Remarks:Select the option in the menu through “▲”and “▼”and then press ENTER for confirmation. When the

menu interface pops up, press MENU and EXIT to quit from this menu interface

2.2.3 User SettingThe interface of User Setting allows the user to set all kinds of parameters for the unit.Select the option of User Setting in the Menu interface and then press ENTER to go to the User Setting

interface. Subsequently, a window indicating “Please input password” will pop up.Remarks:The password for the User Setting is the same with the one for the Startup; however, it can be changed

through the User Setting. Once the correct password is verified by the system, the user can go to the setting interface. If the

password is input incorrectly, a suggestive window will pop up.Through the setting interface, the following items can be adjusted: default parameter (Default Par.), inlet

water temperature for cooling (C Water-in T), hot return water temperature (Hot BW. T), Memory ON-OFF state (Memo. ON-OFF), volume of clicking keys (Key Volume), LCD backlight (Backlight), ON-OFF Mode, timer setting, clock setting, password revision(Pwd. Revision), and Modbus address setting (Modbus Add.).

Remarks:Return Hot Water Temperature (Hot BW.T) is not applicable for the unit without the function of heat

recovery.Select an option through the buttons of “▲” and “▼” and then press ENTER to go to the sub-window of


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it to set the desired value.

Clock Setting:

Timer SettingTimer setting aims to set the ON-OFF time for the unit. Based on the actual need, the user can take one

week (Monday---Sunday) as a cycle to set the timer mode for each day. There are three available timer modes provided for the user, each with four time phases.

a. Setting of the Time Phase under the Timer ModeGo to the Timer Setting, and put the cursor on the place of Mode 1.


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Press ENTER and then the cursor will move to the interface of Mode 1. After that, press “▲” and “▼” to change the time, or select “√” or “--” ( “√” indicated it has been selected, while “--” means it has not). Then, press ENTER to move the cursor away.

After finish the setting of Mode 1, press EXIT to quit from this mode to the main menu shown as below.

The setting of Mode 2 and Mode 3 can also be done in the same way as above.


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Press ENTER and then the cursor will move to the interface of Mode 2. After that, press “▲” and “▼” to change the time, or select “√” or “--” ( “√” indicated it has been selected, while “--” means it has not). Then, press ENTER to move the cursor away.

b. Move the cursor to Set week and press ENTER to select the timer mode for each day within one week.

Press “▲” and “▼” to change the Timer Mode, and press ENTER to change the date.


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c. Move the cursor to Save and press ENTER to save the changed value of the Timer Setting. (Only with this operation, all changes to the Timer Setting can be saved)

When the user is intended to set some parameter under the remote control shielding mode, a prompt dialogue box will pop up, as shown below, indicating “Remote shield! No setting!”


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2.2.4 Module ViewSelect the Module View on the Menu interface and press ENTER to go to the module view interface.

Remarks:The existent module will be indicated by “Yes”, while the inexistent will be indicated by “No”. Besides,

the module marked by “!’ means it is in error or has the automatic anti-freeze function or defrosting function.The inexistent module hasn’t any submenu. Press EXIT to quit this interface and back to the previous menu. Or press “▲” and “▼” to select the

expected module. After that, press ENTER for confirmation.For the existent module, the user can view the submenus of Sampling Information, State View, Current

Error, and Error Record. Press the “▲” and “▼” to switch over four three submenus and then press Enter for more details.

a. Sampling InformationIt is used to view the temperature and pressure of each temperature spot of this module, and it can be

refreshed in real time.

Remarks: When the function of heat recovery of the unit is deactivated, there is no Hot BackWater Temperature

(Hot Backwater T).The displayed pressure is relative pressure, equal to the absolute pressure minus 1.01bar.b. State View It aims to view the load status of each module and it can be refreshed in real time.


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Remarks:Items which are started will show ON, or show OFF. For the compressor, there are several statuses: OFF,

25%, 50%, 75%, and 100%.c. Current ErrorIt aims to view the error status of the current module and it can be refreshed in real time.

When one page is not enough for listing all errors, more pages are needed. Move the cursor to Current Error and then press ENTER, the cursor will go to the place of Next Page. At this time, in the top middle of the page shows Page 1 and the whole page is about the contents of page 1.

Then press ENTER, and the cursor will be at the place of Last page. At this time, in the top middle of the page will show Page 2 of the Current error and the whole page is about the contents of page 2.


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Switch page one to page two by pressing ENTER and press “ ▲” or “ ▼” to switch submenus.Frequent Protection Alarm① .Frequent protection times are accumulated by the single unit, of which the timing and counting are

done individually.② .When “LP protection of comp.,Comp.Phase fault Pro.,Overload pro.of comp. ,Comp.built-in

pro.”occur to the running compressor, its protection times will be accumulated.③ .Protection times will not be accumulated when the unit is in downtime.④ .During the specified period, if both the above conditions happen once, one more frequent protection

time will be accumulated.When it is detected that the accumulated protection times for the compressor are up to 4 in 12 hours, the

frequent protection alarm will work.The following is the interface of the frequent protection alarm.

Remarks:When an alarm is raise for frequency protection, the page will go to the homepage and also show a hint

textbox, saying “Moduls 1 is frequently protected, Please handle it as soon as possible! Or the unit will be locked”. At this time, press ENTER, then all alarm information and lock information will be listed on by one (During this time,all buttons expect ON/OFF and ENTER are deactivated). After that, this textbox will fade away.

Frequent Protection LockIf it is detected that the accumulated protection time for the running compressor is up to 6 in 12 hours,

then the unit will be locked.


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Remarks:When the unit is locked due to frequency protection, this page will back to the homepage and a textbox

will pop up, saying “Module 1 is locked for frequent protections. Startup is forbidden”. At this time, all operations are the same as those of the frequent protection alarm.

Recovery of the Frequent Protection LockOnce the frequent protection is locked, it can be only recovered by inputting the correct unlocking

password. Refer to the factory parameter settings for more details.d. Error RecordIt is used for viewing the error status of the current module. This page contains 16 latest error records,

including error type and occur time. The smaller the serial number of the error, the later it occurs. This error record can still be kept even in the event of power-off and can be refreshed in real time.

Move the cursor to Error Record and press ENTER and then the cursor will go to the place of Next page. At this time, in the top middle of the page shows the Page 1 of the Error Record and all contents are about page 1.

After that, press ENTER and then the cursor will go to the place of Last Page. At this time, in the top middle of the page shows Page 2 of the Error Record and all contents are about page 2.


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2.2.5 Factory ParameterSelect Factory Parameter on the Menu interface. After inputting the correct password, you can go to this

interface, which offers all adjustable parameters of the unit. However, this interface is only available to the factory staffs who know the correct password. Additionally, all contents of this page can be kept even in the event of power-off.

Press “▲” and “▼" to adjust the value of figures and press ENTER to switch to other option . The access to this page is only allowed by inputting the correct password, or it will tell the input password is incorrect.

Press “▲” and “▼" to move the cursor to the place of System password revision and then press ENTER to access to a textbox of system password revision, shown as the below figure.


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0

Press “▲” and “▼" to move the cursor to the expected option and then press ENTER to go to the submenu of it to adjust the value of some items.

2.2.6 ResetGo to the menu interface by pressing MENU at any condition and then press “▲” and “▼" to select Reset

error.

Press ENTER and then a text window will pop up. In this case, select Yes and press ENTER, reset of the unit starts.

2.2.7 Helping This interface introduces four kinds of information: “Operation Instruction”, “Units Introduction”, “Other

Instruction”, and “Version Introduction”, shown as follows:


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3 Electric Principles

3.1 Connections for external control Connections for external control

Chiller water pump contactor for outgoing control (220V front line)Water pump associate

Neutral line for outgoing control

3.2 Wirings ListSpecification for power cord and breaker is recommended as follow:

Model LSBLGF230MT3/Nb-M LSBLGF 350MT3/Nb-M LSBLGF 430MT3/Nb-M

Size of the Power Cable (mm2) 150 185 300

Size of the Ground Wire(mm2) 70 95 150

Capability of the Air Switch(A) 250 320 400

Note: ① .The specifications of the breaker and power cable listed in the table above are determined based on

the maximum power (maximum amps) of the unit.② .The specifications of the power cable listed in the table above are applied to the conduit-guarded

multi-wire copper cable (like, YJV XLPE insulated power cable) used at 50℃ environment temperature and capable of enduring 90 ℃ cable temperature (see GB/T 16895.15). If the working condition changes, they should be modified according to the related national standard.

③ .The specifications of the breaker listed in the table above are applied to the breaker used at 40 ℃ environment temperature. If the working condition changes, they should be modified according to the related national standard.

A piece of square sheet metal removable is equipped where the inlet wire comes in. During installation, remove the metal sheet firstly, which shoud be drilled a hole accoding to dimesion of the cable joint, and then keep the cable through the hole and fix the cable.

Square sheet metal

Hole

Local cable joint Local cable joint Cable sleeve

Square sheet metalCable

3.3 Connection of units and external connection wires

3.3.1 General rules All leads, facilities and connection wires supplied at field must be in accordance with all applicable

laws and project standard.All the connections of wirings at field must be performed by electrician with certification.Connections must be performed after cutting off all power supply.


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The persons who perform the installation must be responsible for any damage resulting from incorrect connection of exterior lines.

Warning- Copper leads must be adopted.

3.3.2 Connect the power cord into electric cabinet of the unitKeep the power cord through slot, wire duct or cable trench.The power cord connected into electric cabinet of the unit must be protected with rubber or plastic

to prevent the edge of the sheet metal from scratching it. The part of power cord near the electric cabinet of the unit must be reliably fixed to prevent external

force affecting the power terminal board of electric cabinet of the unit. The power cords must be reliably ground.

3.3.3 Control wiresThe minimum length of the control lead at filed is 1mm2

The wires connected with water flow switch is with DC light current signal, so never side by side line it and the lead with 50V or more voltage; provided that is actually unavoidable, keep the light current signal above 150mm from the heavy current signal.

The signals for chilled water pump and auxiliary electric heater in electric cabinet of the unit (220V AC; Capacity: 5A), can drive the AC contactors to chilled water pump and auxiliary electric heater, but do not directly drive the chilled water pump and auxiliary electric heater.

The power cord inserted into the unit can not be too long .Never bind the rest of the power cord in the electric cabinet.

3.4 Connection among ModulesModule1 2 ModuleN

Communication Line

3.5 Dial-up switch to main board Four-bit dial-up switch indicates the address of each module (0-7), and the display panel displays in turn

“Module 1, Module 2…….Module 8”. .1234 in the dial-up are binary codes, in which 1 is the least significant bit, and 4 is the most significant bit.


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4 Instruction to installation of unit

4.1 Inspection In order to ensure normal running of the unit and avoid malfunction, the installation should be operated by

the professionals with air-conditioning knowledge and working experience, please read this manual carefully before installation.

The units were manufactured under strict quality control system of the company, and have passed through the strict inspection. Please install, operate and maintain the units according to the manual to keep the unit normally run and extend the unit lifespan. If neglect some special factors in installation, some danger such as installation, startup and maintenance of the unit will occur.

4.1.1 Receiving and checking When units are delivered to the appointed place by contract, the user should organize personnel to check

and accept. a. In terms of the attached documents check equipment model and specification. b. Check whether the unit is damaged and spare parts are all completed.c. Check whether the refrigerant charge is leaked. Having passed through the above checking, if the damage and problems exist, please inform the local

office of our company to solve them.Note：After the equipment checking is completed, safeguard is necessary to be adopted. Do not open the

packing too early to avoid damage to the facility.

4.1.2 Delivery and hoisting Each unit has passed through strict inspection and test, to ensure the unit performance and quality, it

should be very careful to install and carry to avoid damage to control system and parts of pipeline.Before opening the packing, carry the unit closely to the final installation place, and keep the units

upward. When carry the unit, of which the packing has been opened, the process should accord with follows: a. Move the unit with rolling lever: Put three pieces of rolling lever under the unit, make sure the length

of lever is 1/5 longer than the unit width, and keep the unit balanced. b. Hoisting（Please refer to attached Fig.1）

Stay bar

Rigging hole

Fig.1 Sketch for hoisting of the unit① .Pease use the stay bar not less than 2300mm for rigging.


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② .Apply the hole marked with the rigging symbol for figging.③ .When rigging,ensure the angle between the bottom of the unit and the horizontal plane is not large

than 15°.④ .The fan quantity is allowed to be different with that showed in the schematic diagram,and they share

the same rigging means.

4.1.3 Base of Unit installation a. The base of unit installation must be conducted and designed by the professionals according to field

conditions. b. The base of installation must be made of concrete or steel frame, which can bear the running weight of

unit and whose surface must be level.c. Please refer to the base of unit installation sketch (Fig. 2). Exactly put a steel plate and shockproof

rubber joint on the base, and then install the unit with the ground bolts which should be installed 60mm higher than the installation level, at last, perform the second grouting.

d. Keep required space for installation, operation and maintenance of the unit.e. Keep the installation place from fire, tinderbox, and corrosive gas or exhaust gas; spacer for ventilation

should be reserved; take applicable measures as much as possible to decrease noise and vibration.

Fig. 2 Sketch for base of units installation

A（mm) B(mm)

LSBLGF230MT3/Nb-M 2350 2000




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4.2 Outline and dimension of the unit LSBLGF230MT3/Nb-M

abov

e 18

00m

m

front

side

abov

e 10

00m

mab

ove

1800

mm

mai

nten

ance

sp

ace

2000

hois

ting

loca

tion

2300

2020 31

50

hois

ting

loca

tion

2100

elec

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cabi

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wat

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ound

bol

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atio

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fron

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nam

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200

380

430

1522

880


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LSBLGF350MT3/Nb-M

mai

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ance

sp

ace

abov

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00m

m

abov

e 18

00m

mfront

side

abov

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00m

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hois

ting

loca

tion

grou

nd b

olt l

ocat

ion

hois

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grou

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wat

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wat

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22

LSBLGF430MT3/Nb-M

2000

230030

00

5250

2100

4350

2000

mai

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ance

sp

ace

abov

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4.3 Installation and maintenance spacea. The unit should be levelly installed without obstacles, keep each unit above 1m from another unit

lengthways, and above 2 m or much more than 2m breadth wise. If there are obstacles on either side of the units, keep it above 1.8 m from the units. If barrier is on the top of the units, keep it above 2.5m from the units.

more than 1m

more than 1m

more than 2mmore than 1.8m

put the u

nits brea

dthwise

put the units lengthways

b. If obstacles are around the units, keep the unit above 1m from another unit. Keep the unit above 1.8 m from the obstacles on either side of the units; moreover, the obstacles can not be higher than 2.1m. If barrier is on the top of the units, keep it above 3m from the units.

less

than

2.1

m

mor

e th

an 3

m

more than 1.8m more than 1.8mmore than 1m

4.4 Connection of water- pipe system During connection, pay more attention to following points:a. Notice marks of water-in(out) pipe for shell and tube evaporator to prevent incorrect connection of

pipes. b. Flexible joints should be used for the chilled water-in (out) pipe joints of the units to decrease

vibration. c. Thermometer, manometer and sluice valve should be installed at the chilled water inlet (outlet).d. To ensure normal running of the units water flow switch must be installed, which is suggested to

associate with the controller of the units.e. The drain valve should be installed on water-out pipe and manual or auto air release valve should be

installed on the peak or raised location in the water-pipe system. When the units are normally running, it is better to take away the valve handle to ensure that the valve cannot be opened, if not, the water-break accident should happen.

f. Chilled water pipe should be covered with heat insulator to avoid loss of heat as well as condensation.


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g. Impurities in the water-pipe system is unavoidable and will deposit on the shell and tube evaporator, so filter should be installed in front of the water pump.

h. Make sure pass by the units before cleaning the waterway system to avoid sewage flowing into the units.

i. When the ambient temperature is very low in winter, if the units is stopped at night, water in the shell and tube evaporator and the pipes may be frozen to damage the facilities and pipes. In order to avoid freezing, the water pump should be always kept running when the units is stopped. The safe ways are to drain out the water of the pipes or add mixture of ethanol and propanol in water-pipe system to prevent freezing.

Note: Never adopt salt mixtures to prevent it from corroding and damaging the units.

CA

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Fig. 5-3 Installation sketch for the units and water-pipe system.


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5 Maintenance In order to make the unit reliably run for a long time, the unit debugging should be operated by

professionals or personnel with air-conditioning knowledge by the guide, the daily operation and maintenance should be operated by the personnel with specialized training.

5.1 Daily startup or stop of the unit The daily startup or stop of the unit should be operated by the manual controller. The knob switch on the

electric cabinet gate is used to turn on /off the unit during maintenance or in emergencies. The sequence of starting the unit is: turning on the water pump first, then the main unit. The sequence of stopping the unit is: turning off the main unit, then water pump. The power supply must have been supplied for 8 hours before turning off the unit (do not start the water pump), so that heat tape of the compressor can operate, liquid refrigerant kept in the compressor can volatilize to avoid damage to compressor by direct startup of the unit.

5.2 Maintenance of the main parts a. During running of the unit, pay more attention to the pressure of air out / in, if any abnormity exists,

please check and debug. b. Control and protect the equipment, do not adjust any set points on the spot. c. Periodically check tightness of the electric connection wires to timely fasten the loose one.d. Periodically check the reliability of electrical components to timely replace the ineffective and unsafe

parts.

5.3 Requirements to water and contaminant releaseWhen the industrial water is used as the refrigerant liquid, there will be little scale incrustation produced,

but if use the water from well or river, that would be a lot of scale incrustation and sand produced, this is because when the sand and clay is in the evaporator, that will reduce the water flow volume and cause the freezing accident. Therefore, before flowing into the refrigerant liquid system, the water should be filtrated, and demineralized the water by demineralizing plant. Before it is using, the PH value, conductivity, consistence of chlorion, consistence of sulphion etc. should be analyzed. The following is the required water quality standard for the unit:

PH value: 6.5~8.0Conductivity: <200uV/cm(25℃ )

Chlorion：<50ppmSulphuricacid hydronium：<50ppm

Content of iron：<0.3ppmAlkali hydronium：<50ppm

Total hardness：<50ppmSulphion：None

Ammonia hydronium：NoneSilicon：<30ppm

Natrium hydronium：Has no requirementIn spite of qualified water and after lengthy running of the unit, burnt lime and other mineral substances

may still deposit on the surface of shell and tube exchanger, which will affect the performance of heat transfer and can be cleared by organic acid like citric acid and acetic acid.


26

5.4 Maintenance for lengthy shut down If the unit is need to be lengthily shut, inside and outside of the units should be clean and dry. Cover the

units to prevent dust and turn on the water drain valve to drain the water stored in the evaporator.

5.5 Startup of the unit after lengthy shut down Following work should be prepared if stat the unit after lengthy shut downCompletely check and clean the units:a. Clean the water-pipe system.b. Check the water pump.c. Fasten all the joints to lines.

5.6 Replacing components When replacing the components, should only adopt the components, which are supplied by GREE, the

similar components of other company could not be used.

5.7 Cooling system Check the refrigerant charging by checking the air in pressure and air out pressure, if there is leakage or

replacing the components of cooling system, that will need to examine the air tightness, when charging the refrigerant, should accord to the following:

5.7.1 The refrigerant leaks completely If this kind of situation happened, high-pressure nitrogen (15~20 kilogram pressure) or refrigerant

should be adopted for system leak hunting, if need to fill the welding, after the air of system inside drained out, it could be weld. Before charging refrigerant, the whole cooling system should be dry and vacuumized completely.

a. Connect the vacuum pipe at the low-pressure side and high-pressure side of fluorine charging mouth. b. To vacuumize the system pipelines by vacuum pump.c. When it had reached the requirement of vacuity (absolute pressure below 100Pa), to charge the cooling

system by refrigerant bottle, the appropriate charging volume has been marked on the nameplate and the technical parameter list. The refrigerant should be charged from the side of low-pressure pipe.

d. The ambient temperature would affect the refrigerant charge volume, if they haven’t meet the required charge volume, can make the refrigerant liquid circulated, and start up the unit for charging, could short circuit the low-pressure control switch. (Note: After charging, the wiring should be resumed )

5.7.2 Recharge the refrigerant To connect the refrigerant charging bottle at the low-pressure side of the fluorine charging mouth, and

connect the pressure gauge at the low-pressure side and high-pressure side. a. Make the refrigerant liquid circulated, start up the unit, to short circuit the low-pressure control switch

when it is necessary. b. To charge the refrigerant to the system slowly, and check the air in pressure and air out pressure. Warning ！！

When it is in the leak hunting test and air tightness test, could not charge the oxygen, acetylene etc. such these kind of inflammable and poisonous gas to the system, the high-pressure nitrogen and refrigerant only could be used.

5.8 Anti-freezingIf the freezing of tubular heat exchanger flow vent happed, that will cause the serious damage, that is


27

the tubular heat exchanger damaged and leaked, but the damage due to the freezing is not belong to the maintenance range, so should pay more attention to the anti-freezing of following:

a. The units are stopping and stand-by under the lower ambient temperature: If the units are placed out of the room with the outdoor temp. is lower than 0℃ , water in the evaporator should be drained out.

b. When running: If the chilled water flow switch and anti-freezing temp. sensor are ineffective, they may cause water pipes freeze, so water flow switch must be kept the interlocking with the units.

c. When maintaining: When charging the refrigerant or discharge the refrigerant while maintaining, the evaporator may be frozen. Whenever the pressure of the refrigerant in the container is lower than 0.4Mpa, the pipes should be possibly freezing. So, water in the evaporator should be kept flowing or drained out completely.

5.9 Other notificationsa. Regular maintenance: Regularly maintain the units according to the requirement of the specification

to ensure the units operate excellently. b. Refrigerant leakage: If there is any leakage of the refrigerant, stop the unit at once and communicate

with the maintenance worker. Do avoid any fire nearby, as the fire can break down the leaking gas into poisonous gas.

c. Fireproofing: If it happens, turn off the switch of the main power source immediately, and then extinguish the fire by the fire extinguisher.

d. Prevent flammable gas: The units should be kept from the combustibles things such as gasoline, alcohol, etc. to prevent explosion.

e. Error: If the units are stopping due to the malfunction, the reason should be found out and the error should be solved, and then restart the units. It is forbidden to start the units while the error isn’t eliminated. If the refrigerant or the chilled water is leak, turn off all the switches. At this time, if the units cannot be closed through the controller, turn off the switch of the main power source.

f. Please don’t make the circuit that needs the protectors into short connection, or it can cause the error.In order to prolong service life and enhance efficiency and saves energy, it is necessary to conduct check,

maintenance, and repair regularly. User should keep down the check, repair and maintenance circumstance in every month, every season and every year. What is more important is to keep down damage and repair circumstance of unit in detail, it is convenient for technician to deal with error.

Maintenance record of the unit

Check the lubricant level Every dayCheck the water-flow volume Every dayPower Volt and power Every dayCheck the refrigerant amount Every dayCheck the wiring and electric parts insulation condition Every seasonCheck and setup the temp. info Every seasonCheck the dry filter Every seasonChange compressor oil filter Every 3000 HoursChange the compressor axletree Every 40000 Hours


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6 Trouble Shooting

Malfunction Possible cause Solution

Discharge pressure is too

high

A. Cooling① .Atmosphere or other non-condensing gas

in the system;② .Condenser fins are dirty or blocked;③ .The condense air volume is not sufficient

or the condensing fan is malfunction;④ .Air suction pressure is too high;

⑤ .The refrigerant is too much;⑥ .The ambient temperature is too high.

⑦ .Inner system is dirty and blocked (e.g. one-way valve, dry filter)

⑧ .Set value for high pressure s top is incorrect.

B. Heating① .There is air or other non-condensing gas in

the system② .Shell and tube heat exchanger scaling or

waterway system filter blocked.③ .Water flow volume is small.④ .Suction pressure is too high⑤ .Heating is started when terminal load is too

small.⑥ .Set value for high pressure s top is

incorrect.

Exhaust the air from the freon intake. If needed, the unit is vacuumized again;

Cleaning the condenser fins;To overhaul the condensing fan and get

back the operation;Please see “Air suction pressure is too

high”;Discharge the part refrigerant.Check if installation environment for

unit contains well ventilation, and improve it.

Change the dirty components.

Check high pressure switch.

Exhaust the air from the freon intake. If needed, the unit is vacuumized again;

Clean the shell and tube heat exchanger and waterway system.

Adjust water flow volume.Refer to “Suction pressure too high”.

Check high-pressure switch

Exhaust pressure is too

low

① .Air suction pressure is too low

② .The refrigerant is leak or charge is not enough

Please see “Air suction pressure is too low”

Check the leakage and charge the freon

Suction pressure is too

high

① .Air exhaust pressure is too high

② .The refrigerant charge is too much③ .The liquid refrigerant flows into the

compressor from the evaporator.④ .The chilled water-in temp. is higher than

the max. accepted value.

Please see “Air exhaust pressure is too high”

Discharge the part refrigerantCheck and adjust the expansion valve

to ensure the expansion valve sensor is closely touching air suction pipe and completely insulated from the outside.


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Suction pressure is too

low

A. Cooling① .The ambient temp. is too low② .Chilled water in temp is obviously lower

than stipulated value.③ .Flow volume of chilled water is not

enough.

④ .System dirty and blocked (e.g. one-way valve, dry filter)

⑤ .Set value for low-pressure stop is incorrect.B. Heating

① .Environmental temperature is too low.② .System dirty and blocked (e.g. one-way

valve, dry filter).③ .Expand valve is not adjusted or error

occurred. ④ .Refrigerant is charged too less.⑤ .If defrost is normal.⑥ .Set value for low-pressure stop is incorrect.

Check leakage and charge Freon.Check installation circumstance.

Check if water intake and outlet pipe pressure at evaporator is too low, adjust greater chilled water flow volume in proper.

Change blocked components.

Check low-pressure switch.

Change blocked components.Adjust to proper overheat temperature,

and check if there is leakage at expand valve sensor.

Adjust defrost set parameter.

Check low-pressure switch.

Compressor stops due to

motor overload

① .The voltage is too high or low

② .Air exhaust pressure is too high or low

③ .Water return temp. is too high

④ .The overload components have the malfunction

⑤ .The ambient temp. is too high

⑥ .The motor or the terminal has short circuit.

The voltage cannot exceed ±10% of the rated voltage.

Check air exhaust pressure and find out the reason

Check water return temp. and find out the reason

Check the compressor current and compare i t to the full load current stipulated on the specification

Check is installation space of unit contains well ventilation and improve it.

Check the corresponding resistors of the motor and terminal.

Compressor stops due to the action of

the inner temp. controller

① .The voltage is too high or low

② .Air exhaust temperature is too high

③ .The chilled water-in temp. is too high

④ .The inne r t emp . con t ro l l e r o f t he compressor has the malfunction

⑤ .The refrigerant of the system is not enough

Check the voltage and it cannot exceed the above prescribed limit.

Check air exhaust temperature and find out the reason

Check the chilled water-in temp. and find out the reason

Check the freon leakage


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Noise of compressor is

large

① .The liquid refrigerant can flow into the compressor from the evaporator. It can arise “liquid impact”

② .Compressor lacks oil.

Adjust the charging refrigerant and check if the expansion valve and the degree of air suction superheat is normal

Recharge compressor oil.

Compressor cannot start up

① .The overflow relay is tripping and the fuse is burned.

② .The control circuit isn’t connected.③ .No current④ .High pressure protection or low pressure

protection

⑤ .The winding of contactor is burned.⑥ .The phase sequence of the power source is

connected wrong⑦ .Water system has the malfunction and

water flow switch is broken⑧ .The manual controller sends out alarm

⑨ .The on/off time of the manual controller is set wrong

⑩ .The temp. checked by the temp. sensor exceeds the preset value.

Change the damaged components.

Check the control system wiringCheck the power supplyPlease see the above items, regarding

the malfunction of air suction/exhaust pressure.

Change the damaged components.Connect the wires again, can adjust two

wires among themCheck water system

Check the alarm type and adopt the corresponding measures

Check the timer and set it again

Water switch protection

① .No water in the system;② .Water switch error or not being correctly

installed;③ .Water pump error;④ .Not complete vacuum of the water

system;⑤ .Water volume is not enough and is lower

than the limit of the switch.

Add water to the system;Change the water switch or reinstall it

according to corresponding standard.Use spare water pump;

Completely drain out things in the water system;

Increase the water volume according to the designation and inspection table.


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7 Attachments Attached Table 1 : Inspection records before debugging

Installation

Location Min. dimension between the unit and the ambient barriers

Recommended value ＞ 2m

Foundation (Cement/ steel structure) Dashpot

Guard mode (“ ∧ ”-type (Herringbone)/” ∨ ”-type

(Herringbone reverse)

The top point of air cylinder; The bottom point of sunshade

Recommended value ＞ 2m

Routine Inspection on user’s

supporting facilities

The chilled water pipe

system

Water flow (Water pump)（T/h）

The state of cut-off valve (On/Off)

The state of drain valve (On/Off)

The state of water

filter (On/Off)

The state of evacuation valve (On/Off)

Intake Outlet

The value of hydraulic pressure meter

The value of thermometer

Water flow switch is working

normal or not

Heat preservat condition

Each cut-off valve in the water

pipes

Washing times of the pipeline Water quality

Intake Outlet Intake Outlet

Load Connected to fan coil Smooth of air supply outlet

Exhaust enough

Airtight space and heat insulation for user’s

air conditioner

The matching between the cooling capacity and the units

Power source (check it at

the end of the service cable.)

The voltage of power supply（V）

Accepted value: 360~400V Voltage fluctuation % Accepted

value: ＜ 3%

Phase-to-phase insulation resistance Insulation resistance between three-phase and earth

Rab Rbc Rac Min. accepted value Rag Rbg Rcg Min. accepted value

1 1

Insulation of the units (Check it in front of the

main breaker.)


R12 R23 R13 Min. accepted value R1g R2g R3g Min. accepted value

1 1

Insulation of the compressor (Check it from the terminal.)


R12 R23 R13 Min. accepted value R1g R2g R3g Min. accepted value

1 1

The cooling system

Make-up soldering of the

pipeline

To vacuumize（MPa）

Max. accepted value 0.0080MPa Maintenance time

(min)＞

30min

Balance pressure of system I （MPa）

Balance pressure of system II（MPa）

Ambient temp.（℃）

Check and confirm the preset value of control & protection

parts

Low pressure controller High pressure controller Three-phase supply monitor

Water-out temp.（℃）

Stopping time of the evacuation

Setting value (Mpa) CO/

HP

Moment (Mpa)

Setting value (Mpa)

Moment(Mpa) Setting value Setting

value Amplitude Setting value

0.15/0.05 0.05 2.60 0.2 380~400V 5S

Oil pressure difference controller

Setting value (Mpa)

Moment(Mpa)

0.35 0.05


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Attached Table 2: Inspection records on trial run and debug

Trial run

Regular checking

before operation

Water system

Flow direction Water temp.（℃）

Full exhaust（Y/N）

Flow volume （T/h） Water

pressure (Pa)

Intake Full load（Y/N）

90% Flow volume Outlet Ambient temp.

（℃）

Test the units at starting state Pickup current （A） Startup state (Normal/Abnormal)

Test the units after starting for 10min.

High pressure Low pressure Error record

F r e e z i n g t e m p .（℃）

Water-in

System Ⅰ Water-out

System Ⅱ Air-in temp.（℃）

Test the units after starting for 30min. (The water

flow volume should return

to the required value.)

High pressure Low pressure Error record

F r e e z i n g t e m p . （℃）

Water-in

System Ⅰ Water-out

System Ⅱ Air-in temp.（℃）

System condition in the running

Error handling

Test

Flow control of the chilled

water

Finally, adjust water flow volume according to the water-in temp. and the load of user’s air conditioner. （T/h）

Water-out temp. （℃）

Nominal value12/7℃

Unloading condition

System Ⅰ --Water-out temp. at the stopping state（℃）

Stop t ime（S）

Water-out tempat the restartingstate（℃）

The 2nd stop time（min）

System Ⅱ --Water-out temp. at the stopping state（℃）

Runtime（min）

Stop timefor theevacuation（S）

5S

Adjustment records of water-out

temp. control on the spot

System Ⅰ --Water-outtemp. at the stopping state（℃）

Stop t ime（S）

Water-out tempat the restartingstate （℃）

The 2nd stop time（min）

System Ⅱ --Water-out temp. at the stopping state（℃）

Runtime（min）

Stop time for the evacuation （S）

5S

DeliveryGeneral

train for the operator

Notes Emergencystop

Special maintenance

Summary

GREE ELECTRIC APPLIANCES, INC. OF ZHUHAI

Add: West Jinji Rd, Qianshan, Zhuhai, Guangdong, China, 519070Tel: (+86-756) 8522218 Fax: (+86-756) 8669426E-mail: [email protected] www.gree.com

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