A Dunham-Bush South-Africa Publication August 2016 (Vol 3)

A Dunham-Bush South-Africa Publication August 2016 (Vol 3)

ENGINEERING BULLETIN… AUG 2016 (Vol 3)

Equipment : Screw Chillers with Flooded Evaporator

Model : WCFX-E, WCFX-V, WCHX-A

AVX-A, AVX-B, ACHX-A, ACHX-B, AFVX-B

Description : EEV for Refrigerant Flow Control

Products that perform…By people who care

Electronic Expansion Valves (EEV) are provided to various

flooded screw chillers series for refrigerant flow control to

achieve optimum efficiency. EEV can be also supplied to

some models for superheat control of the PHE economizer.

EEV driver(s) is provided to controls the EEV. An EEV

Display Panel is provided for unit with multiple EEV drivers.

Each unit has one, or up to two EEVs to control the

volume of refrigerant flow into the evaporator. The EEV

control is based on refrigerant liquid level in the

evaporator which feedback by a refrigerant liquid level

transmitter. Controller output a 0-10Vdc control signal to

EEV driver(s) to control the refrigerant flow, in such,

maintaining the refrigerant liquid level in the evaporator.

The controller determines a desired level of EEV opening

target depending on difference between Preset

Refrigerant Liquid Level and actual refrigerant liquid level

feedback by the transmitter. EEV opening target is varied

based on rate of approach to desired refrigerant liquid

level precenting significant liquid level fluctuation.

Below diagram shows how the closed loop control works.

Evaporator

Refrigerant

Liquid Level

Sensor

Electronic Expansion

Valve (EEV)

EEV Driver

Controller

EEV Open When Refrigerant Liquid

Level < required liquid level

EEV Close When Refrigerant Liquid

Level > required liquid level


Besides refrigerant flow control during normal operation, the EEV(s) can be also a

preventive action to recover unit from abnormal operation, and to prevent unit from tripping

by alarm. The controller will override the EEV control logic and force EEV in response to

recover unit from abnormal operation, such as below:

a. Low suction pressure

This function prevents the unit from tripping at low evaporator pressure alarm. When

evaporator pressure is approaching low suction pressure cut-off safety setpoint, the

controller will override the capacity control command of the compressor. The compressor

will be forced to hold or unload, and EEV will be forced to open to bring the unit operation

back to normal and safe zone.

b. Low suction-discharge pressure differential

This control function seeks to maintain pressure differential across evaporator and

condenser for proper lubrication and to prevent low suction-discharge pressure differential

alarm. If the controller detects a refrigerant system is operating in low suction-discharge

pressure differential, the SDD control will force the EEV to closes. This starves the

evaporator, which shall lowered the evaporator pressure and subsequently, increases the

pressure differential. When the pressure differential has been built-up and back to safe

zone, SDD control will be off and EEV will regulates according to the unit load demand.

c. Low discharge superheat

Low discharge superheat is an indication of low suction superheat which may increases

risk of liquid flooded back to compressor. When low discharge superheat is detected, EEV

will be forced to close to increases the unit discharge superheat back to safe zone.


EEV(s) in liquid line can be also served as refrigerant isolation

device. When “R/O/L” selector switch is switched to position

“O” (Off), the EEV driver will close the EEV with additional 120

closing steps after the EEV is fully closed. This is to ensure that

the EEV is “fully closed” and tight to isolate refrigerant at it’s

upstream.


Equipment : Chillers

Model : Water-Cooled & Air-Cooled Chillers

Description : Monitored Shipment with “Drop N Tell”

As DB’s slogan says “Products that perform… by people who care.”, DBI has initiated

improvement action to ensure our customer’s interest during unit shipment is protected.

Beginning from December 2015, The Drop-N-Tell impact indicator has been installed on

the above mentioned products. The location of the installation is shown in the pictures

below. The Drop-N-Tell impact indicator is installed in such a way that the indicator can be

clearly seen without the need to remove the unit packaging.

Drop-N-Tell indicators are each made with a high-quality sensors that accurately monitors

G Range impact. If shock impact occurs, the blue arrows snaps into place. The 5G Range

non-resettable model is used as it is suitable for our application.


When leaving factory (No Impact)

After drop impact

When the blue arrow is observed on the Drop-N-Tell, customer shall check the condition

of the unit and inspect for damages immediately. DB representative shall be informed

immediately as well for the follow up actions. In case of any incidents that happened during

the shipment that has caused damage to the unit, this small component but with a big

function may save time and money by bringing transportation damage claims to a quick

resolution. As a preventive action, it serves to inform forwarders to be cautious in handling

the equipment throughout the entire shipment process.


Equipment : Air Handling Unit (AHU)

Model : CS3, eCS3, sCS3

Description : SPEC – Ashley 2.0

As part of Dunham-Bush continuous improvement, DB has released the new generation of

SPEC Ashley 2.0 selection software with new features and enhancements. As compare to

previous SPEC Ashley, the new SPEC Ashley 2.0 is much more powerful thanks to the

new software engine that can provide more advanced features.


With SPEC – Ashley 2.0

NO MORE waiting time to generate GA drawing for submittal!!

NO MORE waiting time for price add of optional items and features!!

NO MORE fill in factory order check sheet that consume a lot of time and

may make mistakes!!

All can be done in SPEC ASHLEY 2.0 by mouse clicks.

Other improvements that has been done on latest software that will help the users:-

• User friendly interface

• Develop new projects according to project requirements

• Easily save, retrieve and modify all the projects

• More details data provided compare to previous version

• Optional items such as heat recovery, electric heaters, humidifier etc readily available

• Estimate the cost of the equipment


Unit GA drawing (To-Scale-Drawing) for submission is generated right when unit selection is done.

The GA drawing can be saved in CAD format for easy integration into designer’s drawings. NO MORE WAITING!!


Unit check sheet is also generated when the unit selection is done. The same check sheet will be send into factory for manufacturing process.

Improve Efficiency!!

Shorten order processing time!!


All the relevant information of the units, for example, lengths, weights, structural profile, panel metal sheets, internal metal sheets, filter and supply fan specifications are generated in the Technical Report.

Simple and user friendly interface. By using “Quick Selection Templates”, user can easily select the unit configuration, unit components and features.


In SPEC Ashley 2.0, there are more offers for heat recovery accessories are included into configuration design. Heat recovery option accessories available:-

• Heat Pipe • Plate Heat Exchanger • Heat Wheel

AUG 2016 (Vol 3)


Every electric motor has to come with some sort of motor controller. The motor controller will

have different features and complexity depending on the task that the motor will be

performing. Motor starter is the switching device used to start and stop a motor. This article

discussed about design, operations and applications of various type of motor starters that

used in HVAC equipment, such as chillers, AHUs, pumps, etc..

1. Direct-On-Line (D-O-L) Starter

D-O-L starter is the simplest and cheapest starter which is applicable to all motors. It

consists of one contactor only with full voltage and full torque starts. Starting current (or

inrush current) occurred is 100% of motor LRA (Lock Rotor Amps) or about 7 times of motor

FLA (Full Load Amps).

Photo of Typical

D-O-L Starter

Typical Wiring Diagram

of D-O-L Starter

Motor Starting Curve with

D-O-L Starter (Current vs. RPM)

≈ 7 x FLA

However, D-O-L starter creates extremely high starting current which may cause serious

disturbance to the power supply grid. Besides current surge on the electrical power system,

it also creates torque surge to the mechanical system. Thus, various type of reduced

voltage starters were introduced to reduce starting current as well as starting torque which

created during motor start-up. Below are some of common reduced voltage starters.

2A. Part Winding / Double Delta Starter

2B. Star-Delta / Wye-Delta Starter

2C. Auto-Transformer Starter

2D. Reactance Starter

With technological advancement in electronics industries, solid-state-starter and drives

become more common in the HVAC applications. Both solid-state-starter and drives are

more advanced than any type of the reduced voltage starters by offering controllable and

adjustable starting current and other features like soft-stop, torque control. Drives are more

advanced with the capability of performing motor speed control.

3A. Solid-State-Starter / Soft-starter

3B. Variable Frequency Drive (VFD) / Variable Frequency Drive (VSD)

Equipment : ALL

Description : Various Type of Motor Starter HVAC Equipment

ENGINEERING BULLETIN…

AUG 2016 (Vol 3)


2A. Part Winding / Double Delta Starter

Part Winding Starter is only applicable to motors designed with two identical windings in

parallel, wye-wye or Delta-Delta. Dunham-Bush Vertical Screw MSC compressor motors

(127 & 192 series) are designed with two Delta windings, thus, it works together with Double

Delta Starter as the standard reduced voltage starter. Part Winding Starters consist of two

identical contactors. The motor is started up with 50% of full voltage. Thus, the motor starting

current by part winding starter is about 50% of motor LRA, or around 3.5 times of motor FLA.

Photo of typical

Part-Winding Starter


of Part Winding Starter


Part Winding Starter

≈ 3.5 x FLA

DOL Starter

Part Winding

Starter

2B. Star-Delta / Wye-Delta (Y-∆) Starter

Y-∆ starter is applicable for motors designed with 6 leads terminal post and suitable for Y-∆

starting. Y-∆ motor with windings connected in Delta (∆) when operating in nominal voltage.

Windings are first connected in wye (Y) configuration during start-up; reconnect to Delta (∆)

connection when motor has comes up to speed.The motor is started up approximately 58%

of full voltage, as motor windings are connected in wye (Y). Thus, the motor starting current

is about 33.3% of motor LRA, or about 2~3 times of motor FLA.

Dunham-Bush Vertical Screw MSC compressor motors (223 series) and new Horizontal

Screw HSC compressors motors are designed with Wye-Delta windings, thus, it works

together with Star-Delta Starter as the standard reduced voltage starter.

Photo of typical

Y-∆ Starter


of Y-∆ Starter


Y-∆ Starter

≈ 2.5 x FLA

DOL Starter Star-Delta /

Wye-Delta Starter


AUG 2016 (Vol 3)


2C. Auto-Transformer Starter

Auto-Transformer Starter is applicable for all induction motors. Auto-transformer starters

consist of contactors and transformer, which the transformer generally comes with 3 tapping

points, there are 50%, 65% and 80% tapping. Auto-transformer starters use the transformer

as voltage limiting device, in such, limits the current drawn by motor during start-up. For

typical auto-transformer starter with 65% tapping, 65% of full line voltage is applied during

the motor start-up. Starting current will be about 42% of motor LRA, or about 3 times of

motor FLA.

Photo of typical

Auto-Trans Starter


of Auto-Trans Starter


Auto-Trans Starter

≈ 3 x FLA

DOL Starter

Auto-Transformer

Starter

2D. Reactance Starter

Reactance starter connects resistors in series with each of the motor windings during start-

up. With this additional resistance to the loop, start-up current drawn by the motor is reduced.

However, voltage applied on the motor is reduced as well and thus, produces less starting

torque. The resistors are generally selected to starts the motor at approximately 70% of full

voltage. Thus, the motor starting current is about 70% of motor LRA, or about 4 to 5 times of

motor FLA.

Reactance starter is not popular in Low Voltage (LV) applications. However, it is more

common in Medium Voltage (MV) applications.

Photo of typical

Reactance Starter


of Reactance Starter


Reactance Starter

≈ 4 x FLA

DOL Starter

Reactance Starter


AUG 2016 (Vol 3)


3A. Solid-State-Starter / Soft-Starter

Solid-State-Starter or Soft-Starter is applicable for all induction motors. Soft-starters use

SCRs (Silicon Controlled Rectifier) or Thyristors to control current drawn by motor during

start-up. Thus, biggest advantages and advancements given by soft-starter compare to any

type of reduced voltage starters are controllable starting current and torque, and smooth

starting to reduced mechanical stress on motor during start-up. 2nd inrush current or

changeover inrush current that occurred in other reduced voltage starters is not applicable to

soft-starters. No changeover inrush current with soft-starter.

In general, motor starting current by soft-starter is around 2 to 4 times of motor FLA

depending on the applications. Besides the built-in motor protection, most of the soft-starters

in today’s market are also having soft-stop as standard feature. This is a good feature

especially when works with water pumps as this helps to prevent water hammering during

pump start and stop, and thus, extend life span of pumps. Soft-starters are usually installed

with bypass contactor, either with built-in bypass or external bypass. Soft-starter will bypass

the line current to bypass contactor after the motor start-up sequence has been completed.

This greatly reduced heat losses at soft-starter.

Photo of typical

Soft-Starter


of Soft-Starter


Soft-Starter

≈ 3 x FLA

DOL Starter

Soft-Starter

3B. Variable Frequency Drive (VFD) / Variable Frequency Drive (VSD)

VFD or Drives is so far the known best motor starter which can be used at all type of motors.

Motor starting by VFD is fully controllable and thanks to this smooth starting, the

mechanical stress on motor during start-up is drastically reduced. Motor start-up by VFD

gives the lowest starting current, which is always less than motor FLA. VFD utilized

rectifier bridges, DC capacitor and IGBTs (Insulated-Gate Bipolar Transistor) to visualized

motor speed control and regulation. Thus, VFD is not just a motor starter, but it is also a

motor controller with built-in motor speed control logics, as well as built-in motor protections.

Besides the excellent motor start-up mechanism, most of the VFDs available in today’s

market will also improved displacement power factor of the motor to the level of 0.95 or

above. Thus, besides low starting current which benefits the power grid design, VFDs are

also helping to reduce heat loss at power distribution line.

However, the biggest benefit of VFD applications on HVAC equipment is the impressive

energy savings during partial load operation which is much more efficient than the

mechanical unloading mechanism. The energy saved is dramatic for applications such as

compressors, fans, centrifugal pumps and blower fans, and etc..


AUG 2016 (Vol 3)


There are a lot more benefits by using VFD, however, designers shall put equal attentions

on some drawbacks by using VFDs, such as efficiency losses and harmonic

distortions.There are commonly 2 to 3% losses across the VFD at full load operation and

the losses are converted into heat dissipations. The efficiency losses on VFD can be easily

recovered from the energy savings gained by VFD operation, however, ventilation of VFDs

shall be taken care as not to overheat the VFDs.

Harmonic distortions and Electromagnetic Interference (EMI) is another point that worth

attentions from designers to minimized the side impacts. VFDs installed shall be equipped

with EMC filter which shall comply to IEC/EN 61800-3:2004. VFDs shall also comply with

IEC/EN 61000-3-2 and IEC/EN 61000-3-12 Standards to restrict the level of harmonic

distortions. EMI may caused signal interference to sensitive devices, while harmonics may

caused damages on sensitive devices, as well as overheating on motor windings and

cabling. For critical applications, harmonic distortions can be mitigated to desired level by

using harmonic filters which widely available in the market.

IEEE Standard 519-2014 (IEEE Recommended Practice and Requirements for Harmonic

Control in Electric Power Systems) specifics maximum harmonic level permitted in a

electrical power system. However, restrictions on harmonics level as specified by IEEE

Standard 519-2014 are focusing on the Point of Common Coupling (PCC) with the

consumer-utility interface, not at individual equipment.

Photo of typical

VFD


of VFD


VFD

FLA

WCFX-V Water-Cooled Variable Speed

Screw Chiller

AVX-B Air-Cooled Variable Speed

Screw Chiller


AUG 2016 (Vol 3)


Below are summary of starting current, advantages and disadvantages of various type of

starters.

Below are summary and comparison of expected starting current (% of FLA) versus motor

speed (RPM) curves of various type of starters.

DOL Starter

Part Winding Starter

Star-Delta Starter

Soft-Starter

VFD

Starter Type Expected Starting

Current Advantages Disadvantages

Direct-on-Line (DOL) 100% of LRA ≈ 7 times of FLA

Simple, lowest cost

Highest starting current

Part Winding (Double Delta)

50% of LRA ≈ 3.5 times of FLA

Simple, low cost High starting current

Star-Delta (Y-D) 33.3% of LRA ≈ 2 to 3 times of FLA

Simple, low cost High starting current

Auto-Transformer 42.3% of LRA (65% tap) ≈ 3 times of FLA

Lower starting current

Lower starting torque

Reactance 70% of LRA (70% tap) ≈ 4 to 5 times of FLA

Higher starting torque

Higher starting current

Soft starter / solid state

Adjustable and controllable ≈ 2 to 4 times of FLA

Low starting current and controllable

Higher cost

Variable Frequency Drive (VFD) / Inverter

< FLA Best starting method

Highest cost


APPLICATION BULLETIN… AUG 2016 (Vol 3)

Equipment : Air Handling Unit (AHU)

Model : CS3, eCS3, sCS3

Description : AHU For Outdoor Installation

Dunham Bush Air Handling Unit (AHU) CS3, eC3 and sCS3 Series are designed for indoor

installation. The AHUs construction design can be configured for draw thru or blow thru

application, with blower arrangement in either horizontal, vertical, or footprint-saving

arrangements. Site-assembly option is available with unit delivered to site in sections,

which is very helpful for renovation and retrofit jobs. The sections can pass through

standard doorways, and fitted into cargo lifts.


CS3 and sCS3 series AHUs will be good for outdoor installation with add-on accessories

and features as below.

Pitch Roof Powder Coated Casing &

Base structure

Recommended

in One Section

Stainless Steel

Fasteners


RT Access

Door

Air Hood

Dunham Bush RT-AHU Series is designed and manufactured specifically for outdoor

installation. Besides all the required accessories and features as mentioned above for

outdoor installation, RT-AHU series is also designed with provision for blower fan with

down flow configuration. RT-AHU series is the ultimate solution of AHU for weather proof

operation.


Recommended add-on accessories for outdoor installations.


Equipment : Air-Cooled Chillers

Description : Adiabatic Air Inlet Cooling System

Global warming and increased in climate temperature bring more and more challenges to

designers and operators to design and operate a HVAC system efficiently. Increasing in

ambient temperature gives direct impact to air-cooled chiller systems as the chillers’

efficiency are very much depending on the ambient dry bulb temperature. Hotter summer

days will give additional stress to the air-cooled chillers operation.


The phenomena above increases the heat rejected by the chiller up to 40% or even more

depending on design and operation. By reducing the on-coil air dry bulb temperature and

keeping the coil clean, it is possible to realized peak savings to be as much as 30-40% with

annual savings of 15-25% depending on the location, application and operational patterns

of the system.

Adiabatic Air Inlet Cooling or Evaporative

Cooling System is a technology introduced to

work together with an air-cooled chiller, which

to improve chiller efficiency by lowering the

on-coil air dry bulb temperature at air-cooled

condensers via the evaporative cooling cycle.

See Figure 1 on the left which explained the

working principle of this air inlet cooling

system. Figure 2 below shows the potential

reduction on air intake dry bulb temperature

across the evaporative cooling cycle in

relation to relative humidity of ambient air.

Discharged

Air

Hot Air

Cooled

Evaporative Air

Figure 1

Figure 2

Hot Climate

Temperate Climate

How the system works?

The air inlet cooling system is activated

by an external command, either by

ambient temperature, or the chiller’s

head pressure. When the system is

activated and water is sprayed around

the chiller, below processes will take

part to improve the chiller operation.

A. Water evaporation in air reduces the air

temperature significantly thanks to the

evaporative cooling effect.

B. Water drops not evaporated in air will

then deposit on the fins of the coils and

water starts to evaporate into the air

streaming through the coils. This

evaporation is forced by the so-called

mass convection.


Below DB air-cooled screw chiller, model ACHX-A 210T was installed with adiabatic air

cooling system for a project located in Middle East region. Concept of the design is to

activate this adiabatic air cooling system during summer season to lower the chiller

operating head pressure, as well as to maintain the chiller’s cooling capacity when operate

at extreme high ambient temperature. This unit is designed to operate without fail for

ambient temperature up to 125oF [52oC].


Click HERE to see the operation

This cooling system comes with mesh which to be placed in front of the condenser coils. Water

spray is triggered by ambient temperature and it is sprayed onto the meshes via nozzles. This

provides an adiabatic cooling effect on the incoming air, reducing the temperature before it has

even reached the condenser coils and reducing power consumption. Factory testing shows that

the adiabatic cooling system has lowered the on-coil air dry bulb temperature of condenser coils by

10oF [5.5oC].

Figure 3 – Layout of Adiabatic

Cooling System

https://youtu.be/30vTvJ8nhDY

SERVICE BULLETIN… AUG 2016 (Vol 3)

Equipment : All Chillers

Model : Chillers with Built-in Controller

Description : Disconnected Controller Power Supply Prior To

Shipment

DB Product Quality team was aware of increasingly controller failure prior to testing &

commissioning of chiller, since year 2015. After careful studies and investigations of

various departments, it was concluded that the root cause of such failure was improper

handling at site, such as, chiller’s base was used as “Earthing” of welding machine when

site installers were setting up inter-connection piping from chiller to system water piping.

Welding machine draws high current when it was in operation. Power supply of the

controllers are “Earth” to the electrical enclosure. Thus, the above wrong practice may

cause high voltage spike to the controller, and thus, damage the controller.

In order to protect the user’s benefits, Service Bulletin SB002/16 has been issued at Mid

March 2016 to enforced practice to disconnect all power supply connectors from controllers

prior to unit shipment.


The circled connectors as shown in the pictures above shall be supplied in disconnected

form as a preventive action to avoid any damage to the electronic parts before Testing &

Commissioning. Each connector is tagged and its matching corresponding connection

point on the controller body is also tagged. These connectors are to be re-connected to the

controller as per tag during Testing & Commissioning.

CASE STUDY #1… AUG 2016 (Vol 3)


The Customer

The 2200 building is located on Biscayne

Boulevard in downtown Miami. The building is a 7

story, 97,500 ft2 office building and data center.

CASE STUDY 2200 Building – Low Noise Water-Cooled Chiller for Outdoor Installation

Challenges

The 2200 building had an old chiller that wasn’t

very efficient and was very costly due to equipment

deterioration. The building owner didn’t have space

inside the building for a new water-cooled chiller,

or any space outside for an air-cooled chiller.

Solution

Dunham-Bush teamed up with local representative to design the WCFX-E water-cooled chiller for

outdoor installation. The building is just 500 meters away from sea side and is located in a semi-

residential area. Model WCFX38TAR was proposed with below features:

• Rated cooling capacity 260 Ton; Full load efficiency 0.6kW/Ton with IPLV 0.41kW/Ton

• IP55 rated electrical and control panels, and compressor terminal box.

• Weather proof accessories for those installed out of electrical enclosure; stainless steel fasteners

• Anti-corrosion painting (Rated to withstand 5000 hours salt spray test as per ASTM B-117)

• Compressor sound enclosure

• Factory mounted condenser pump starter with motorized valve controls

• Factory mounted Variable Speed Drive (VSD) for cooling tower fan control

Results

The high efficiency WCFX-E chiller has provided a tremendous savings to the customer. With the

compressor sound enclosure, the unit operational sound is only 66 dBA, measured at 3ft from chiller.

ENGINEERING SOLUTION │ Tailor Made Chiller

Click HERE to see and hear the unit operation

https://www.youtube.com/watch?v=0c6g5w-UvBg&feature=youtu.be


ENGINEERING SOLUTION │ Low Temp. Industrial Chiller

The Customer

GlaxoSmithKline plc (GSK) is one of the world's largest pharmaceutical company,

and was the first global healthcare company to establish a presence in Singapore.

GSK is a science-led global healthcare company who research and develop a broad

range of innovative products in three primary areas of pharmaceuticals, vaccines and

consumer healthcare sciences industry. GSK Global Manufacturing Plant located at

Jurong, Singapore manufactures active pharmaceutical ingredients (APIs) used in a

variety of GSK prescription medicines.

CASE STUDY GSK – Low Temperature Process Cooling Chiller

Challenges

The process cooling fluid was supplied by two number of 20 years old chillers, each with rated

capacity 120Ton. Performance of the chillers were de-rated a lot over the time, and was operated at

efficiency of 2.2kW/Ton. Chillers were operated with high power consumption, as well as huge

maintenance cost. The client plan to replace two chillers with one bigger chiller for best ROI (return

of investment), with below design requirements.

i. Capacity = 245TR

ii. Fluid Type = 45% EG (Mono-Ethylene Glycol)

iii. Entering / Leaving Fluid Temp. = 6.8/-5.8oF [-14/-21oC]

iv. Pressure vessels to be certified by MOM (Ministry of Man Power, Singapore)

v. Unit to be installed at outdoor, with shelter above the unit to avoid direct sunlight and rain water

vi. Multiple compressors for redundancy

vii. 24/7 continuous operation

viii. Full load efficiency to be less than 1.9kW/Ton




Solution DB IWCHDX 240-5Q was supplied. Unit was designed with 4 no’s of screw compressors with twin

refrigerant circuits for reliable operation and ease of servicing. Unit was also designed to have

provision to deliver chilled fluid temperature down to -7.6oF [-22oC]. This water-cooled chiller was

designed to meet Ingress Protection Rating at IP55, which suitable for outdoor operation.

Inspector from authorized agency by MOM (Ministry of Man Power, Singapore) attended to factory

during fabrication of vessels to inspect and certify the vessels in accordance with MOM’s guidelines

for pressure vessel. Evaporator was insulated with 2” thick PU foam (by injection) with stainless steel

jacketing in factory to prevent condensation on evaporator due high humidity ambient and low

temperature operation.

Results

The chiller has been commissioning early

year 2016 and has undergoes extensive

tests at site including performance test,

reliability test, stress test, etc.. Upon the

success, the process cooling cycle has been

transferred to new chiller and the client is

now enjoying the operational cost saving

with dramatic reduction on chiller power

consumption; the new chiller is operated at

efficiency of 1.8kW/Ton. Consistent and

precise temperature control of leaving

chilled fluid delivered by chiller to the

process cooling cycle also helps on

consistency of product output quality.

Unit Specifications

Chiller Model : IWCHXX 240-5Q

Refrigerant : R507

Compressor : 4 x Horizontal Screw

Refrigerant System : Two

Compact foot print of the chiller compared to existing chillers has also saved precious space in the

factory for chiller installation. As new chiller is installed in outdoor plantroom, the existing indoor

chiller plantroom will be no longer in used and can be valuable space for factory’s future expansion.



ENGINEERING SOLUTION │ High Efficiency WCFX-V Chiller

The Customer

PKNS (Perbadanan Kemajuan Negeri Selangor), or Selangor Development

Corporation is a development Corporation fully owned by Selangor State

Government, in Malaysia. PKNS involved actively in properties development in

the state of Selangor, as well as building the community.

CASE STUDY Laman PKNS – High Efficiency Chiller for Green Building

Challenges

Laman PKNS is PKNS’s new headquarter located in Section 14, Shah

Alam. This RM170 million building is designed to meet Malaysia’s Green

Building Index (GBI) Platinum rating. GBI is created by Malaysia in

reference to other international Green Building certification programs as

well as considerations taken on actual needs and project executions in

Malaysia. GBI assessment criteria for Non-Residential New Construction

(NRNC) include Energy Efficiency, Indoor Environmental Quality,

Sustainable Site Planning & Management, Material & Resources, Water

Efficiency and Innovations. Platinum rating is the highest rating which

required minimum scoring of 86 points out of 100 points.

One of the important assessment criteria for GBI is Energy Efficiency Performance. GBI Platinum

building is designed with BEI (Building Energy Index) around 100kWh/m2.year. As air-conditioning

system consumed more than 60% of building total power consumption, a high efficiency chiller

system is crucial to meet such criteria. The chiller system of Laman PKNS is designed with variable

speed water-cooled screw chillers with variable primary flow pumping system for energy saving

operation. The Air Handling Units (AHU) are designed to incorporate Electronic Air Cleaner (EAC) for

intake air filtration, and variable speed drive (VSD) on blower fan motor for motor speed control.



Results

Laman PKNS has successfully pass the GBI’s Design Assessment and obtained the GBI Platinum

Certification. Achievement of Laman PKNS is remarkable as this is one of the very few buildings that

can achieve GBI Platinum rating in Malaysia.

Solution Below equipment was supplied:-

3 x 400TR Variable Speed Water-Cooled Screw

Chiller - WCFX-V 50T

21 x AHU - CS3 series

The 400TR WCFX-V 50T chiller is designed with

supreme efficiency with full load efficiency 0.572

kW/Ton [COP 6.15] rated at Malaysia standard

design conditions. The chiller operates even more

efficient at partial loading condition with part load

efficiency up to 0.426 kW/Ton [COP 8.26].

The AHUs (CS3 series) are furnished with factory

installed Electronic Air Cleaner which served as

pre- and secondary filter of the unit. This feature

also helps to score 1 point under IN1 (Innovation).

Blower motors are also furnished with factory

supplied variable speed drive (VSD) for speed

control to maximized the operation savings of

AHUs.

This high efficiency performance assured the GBI scoring in assessment criteria EE5 (Advanced EE

Performance – BEI) which can contribute up to 15 points. The green refrigerant R134a with zero

ODP (Ozone Depletion Potential) used in WCFX-V chiller is also helps to score 1 point under MR6

(Green Products – Refrigerant & Clean Agent). Vessels of the chillers are designed to obtained

Malaysia JKKP approval (JKKP is equivalent to DOSH in English). JKKP approved vessels are

having more stringent requirements than ASME coded vessels.

DUNHAM-BUSH WORLWIDE…

Singapore Malaysia

China

South Africa

Dubai

Indonesia

Vietnam

Thailand

United Kingdom

Malaysia

Lot 5755-6, Kidamai Industrial Park, Bukit Angkat 43000, Kajang Selangor Darul Ehsan

Tel: +603-89249000 Fax: +603-87395020

China

No 1 Dunham-Bush Rd Laishan District, Yantai, Shandong Province, China 264003

Tel: +86-535-6588999 Fax: +86-535-6581999

United Kingdom

No 8, Downley Road, Havant, Hampshire, England PO9 2JD

Tel: +44-2392477700 Fax: +44-2392450396

United States of America

2125 NW 86th Ave Doral, Florida 33122 United States of America

Tel: +305-883-0655 Fax: +786-527-3539

South Africa

57, Sovereign Drive Route 21 Corporate Park Irene, Pretoria South Africa

Tel: +27-123454202 Fax: +27-123454203

Singapore

2 Kallang Pudding Road, #07-07, Mactech Building Singapore 349307

Tel: +65-68422012 Fax: +65-68422013

Indonesia

Vietnam

10th Floor, Nam A Bank Tower, 201-203 Cach Mang Thang 8 Street, District 3, Ho Chi Minh City, Vietnam

Tel: +84-862903108 Fax: +84-862903109

Thailand

1, Qhouse Lumpini, 27th Floor, south Sathorn Road, Tungmahamek, Sathorn, Bangkok, Thailand 10120

Tel: +66-026103749 Fax: +66-026103601

AUG 2016 (Vol 3)

The Vida Building 7th Floor Jl. Raya Pejuangan, No 8 Kebon Jeruk, Jakarta 11530, Indonesia

Tel: +62-2129778100 Fax: +62-2129778001

UAE

Office # 2606, Fortune Executive Towers, Cluster T1, Jumeirah Lake Tower Dubai,UAE

Tel: +971- 44439207 Fax: +971-44439208

United States of America

Documents

A Dunham-Bush South-Africa Publication August 2016 (Vol 3)