dunham-bush afhx-6sr-77-191tr

8/18/2019 Dunham-Bush AFHX-6SR-77-191TR

1/28

Products that perform...By people who care

AFHX Series 60Hz Air Cooled Screw Flooded Chillers

Cooling Capacity: 77 to 191 TR (271 to 672 kW)

R 134a


2/28

- 2 -

INTRODUCTION

For more than 100 years, Dunham-Bush has focused on innovative product development. Today, we

provide a full portfolio of HVAC/R products from Fan Coil Units to large centrifugal chillers as well as

many other innovative green solutions. Our commitment to innovation, matched with an aggressiveattitude toward growth, makes Dunham-Bush a leader in global markets. Our product development is

tailored to meet the specific needs of customers, building-by-building, country-by-country and region-by-

region. No other HVAC/R manufacturer takes this approach to meeting your performance expectations.

AFHX, Air Cooled Screw Flooded Chillers, have a cooling capacity range from 77 to 191 TR [271 to 672

kW] in 60Hz version using environmentally sound HFC-134a refrigerant. The entire product line features

energy efficiency, installation ease, control flexibility, high reliability and advanced 2020i controller. The

AFHX range is AHRI certified and ETL listed.

TABLE OF CONTENT

Page NoIntroduction .......................................................................................................................................................................................... 2Nomenclature ....................................................................................................................................................................................... 2

Advantages of Flooded Chiller ............................................................................................................................................................. 3Unit Features ........................................................................................................................................................................................ 5Operating Benefits ............................................................................................................................................................................... 8Typical Sequence of Operation ............................................................................................................................................................ 9

Application Data ................................................................................................................................................................................. 10Physical Specifications ....................................................................................................................................................................... 11Performance Data .............................................................................................................................................................................. 13Dimensional Data ............................................................................................................................................................................... 15Floor Loading Diagram ....................................................................................................................................................................... 18Dimensional Clearance ...................................................................................................................................................................... 19Evaporator Water Pressure Drop ....................................................................................................................................................... 20Sound Pressure Data ......................................................................................................................................................................... 20Condenser Fan .................................................................................................................................................................................. 21Electrical Data .................................................................................................................................................................................... 21Typical Wiring Schematic ................................................................................................................................................................... 22Guide Specifications .......................................................................................................................................................................... 26

NOMENCLATURE

A F HX 150 T - 6 S R - HR

Air Cooled Chiller

Flooded Evaporator

Nominal TR

HR = Heat RecoveryLN = Low Noise

5 = 50Hz6 = 60Hz

S = StandardQ = Special

Horizontal Screw Compressor

T = Optional TwoCompressors

Blank = Standard

Blank = R22R = R134a


3/28

- 3 -

ADVANTAGES OF FLOODED CHILLER

In a flooded evaporator the refrigerant surroundsthe tubes in the shell and the water to be cooledflows through the tubes. The level of liquid

refrigerant in the shell is maintained by thecombined action of an electronic level controllerand mod-motor actuated ball valves whichregulates the subcooled liquid refrigerant into theevaporator. This ensures that all the evaporatortubes are completely immersed in the liquidrefrigerant for better heat transfer efficiency.

For a Direct Expansion (DX) Evaporator therefrigerant is expanded into the tubes while thechilled water is circulated through the shell. Athermostatic expansion valve is used to throttlethe refrigerant in maintaining constant superheat

of suction gas to the compressor.The following are the advantages of using aflooded chiller:

1. Higher Capacity and Higher EERachievable with the Same Compressor

The flooded evaporator with all the coppertubes immersed in the “boiling” liquidrefrigerant enables a small approachtemperature between the “boiling” liquidrefrigerant temperature in the shell and theoutlet chilled water temperature in the

evaporator tubes to be achieved. Thisapproach temperature or temperaturedifference between the evaporatingtemperature of the boiling liquid refrigerant andthe chilled water outlet temperature, for aflooded evaporator, is typically less than 3°F[1.7°C].

On the contrary, for a DX or Direct ExpansionEvaporator, the typical approach temperatureis between 8°F [4.4°C] to 10°F [5.5°C]. Thissimply means that the same compressor in aflooded evaporator system will operate at ahigher saturated evaporating temperature

when compared to the same compressor in aDX Evaporator system, when outlet chilledwater temperatures in both cases are set atthe same temperature.

Figure 1 shows the typical screw compressorcapacity performance curve at a particularcondensing temperature over saturatedevaporating temperature of between 30°F[-1.1°C] to 50°F [10°C], and the typical powerinput curve over the same conditions. It can benoted that the same compressor whenoperating with a flooded evaporator willgenerate approximately 8% more coolingcapacity while kW input increases by approx1.8%. Therefore, the same compressor, whencoupled to a flooded evaporator, will typicallyachieve higher cooling capacity with

correspondingly higher Energy Efficiency Ratio(EER) i.e. (BTU/Watt) or lower kW/TR.

FIGURE 1

A DX Evaporator uses TXV throttling tomaintain about 10°F [5.5°C] to 15°F [8.3°C]suction superheat to prevent liquid flood backto the compressor. In a flooded evaporator, therefrigerant boils off in the shell and gas can besucked out from the top of evaporator back to

compressor. The suction superheat is usuallyabout 2°F [1.1°C] to 3°F [1.7°C]. Reduction insuction superheat will further increase thecapacity performance of the compressor.

DX Evaporators are typically designed withhigher tube velocities to ensure proper oilreturn to compressor both at full load and atreduced load. This will contribute to higherrefrigerant pressure drop through theevaporator. On the contrary, there is very littleshell side pressure losses for a floodedevaporator. Therefore, lower suction pressuredrop in the flooded design will impose lesscapacity penalty on the compressor and thiswill further enable the compressor in a floodedevaporator to generate more capacity than onewith a DX Evaporator.


4/28

- 4 -

ADVANTAGES OF FLOODED CHILLER

2. Better Part Load Performance

The Dunham-Bush Air Cooled Flooded Chiller

with its sophisticated advanced controller andpatented oil management system has all

evaporator tubes completely immersed in the

“boiling” liquid refrigerant to achieve superior

heat transfer efficiency while ensuring

adequate oil return to the compressor(s). This

ensures superior full-load efficiency and even

better part-load efficiency as the full heat

transfer surface areas of the evaporator tubes

are utilized even at part-load conditions. In

Direct Expansion Evaporators, because of the

need to maintain adequate refrigerant gas

velocities in the evaporator tubes for proper oilreturn, it is typical for certain bundles of

evaporator tubes to be “blocked” or “baffled

off” at part-load conditions. Therefore not

utilizing the full heat transfer surface of the

evaporator tubes means lower efficiency when

compared with a flooded evaporator chiller at

part-load conditions.

3. Flash Economizer/ Vapor InjectionCycle for Increase Capacity and HigherEER

The renowned Dunham-Bush screw

compressor allows for flash economizer vapor

injection cycle to be incorporated, increasing

capacity by as much as 25% with marginal

10% to 15% increase in kW-input. Most of

Dunham-Bush’s competitors who produce

Rotary Screw Chillers do not incorporate flash-

economizer vapor injection cycle- not to

mention flooded evaporator!

4. Excellent Capacity Modulation in

Response to Build ing LoadsDunham-Bush utilizes its state-of-the-art

advanced controller in combination

with the electronic level controller and

modulating motor actuated ball valves to

ensure precise control of liquid refrigerant to

the flooded evaporator in response to changes

in cooling load. While maintaining leaving

chilled water temperatures even at very low

load. Whereas most of Dunham-Bush’s

competitors utilize orifice plates to modulate

refrigerant feed to the evaporator, resulting in

lower efficiency at low-load and less reliable oilreturn.

5. Maximum Reliability and Redundancy

Today, the Dunham-Bush screw compressors

are increasingly accepted for its reliability. The2-compressor, 3-compressor and 4-

compressor models are designed to have 2

independent refrigerant circuits for

redundancy. For the refrigerant circuits with 2-

compressors (i.e. 3-compressor and 4-

compressor models), individual compressor is

provided with suction stop valve, suction check

valve, discharge check valve and other

isolating valves in the oil management system

to allow complete isolation of an unlikely faulty

compressor without contaminating the

refrigerant system and further allows othercompressors to continue to operate - thus

ensuring maximum redundancy

6. Cleanable Evaporator

For a single pass evaporator join in a row, the

end plates at both ends of the water boxes (2

pass only at return end and 1 pass ‘u’

arrangement only at ‘u’ elbow end) can be

removed easily without dismantling the chilled

water piping connections, for inspection and

for mechanical tubes cleaning with brushes or

auto-brush. This will enable low tube fouling

factor in the evaporator to be ensured, thus

maintaining system efficiency.

7. Lower Water Side Pressure Drop

In a DX Evaporator, the water flows

transversely over the outside of the tubes. The

water flow is guided with vertical baffles. This

will have a higher-pressure drop compared to

the water flow in the tubes of a flooded

evaporator. In other words, the equivalent

flooded chiller will require smaller water pumpto operate at lower power consumption.

8. Commonly Used In Large TonnageChillers Where Effic iency Is Critical

As a general rule, DX Evaporators are typically

used in small and medium tonnage chillers

where efficiency may not be a primary

consideration but cost is important. However,

with increasing energy cost and the drive to

reduce global warming, flooded evaporator

chillers will increasingly become more

popular not only in the large tonnagechillers but also in the small and medium

tonnage chillers. Dunham-Bush, again,

leads the industry in this respect!


5/28

- 5 -

UNIT FEATURES

ADVANCE CONTROLLER

Vision 2020i a flexible and advance

programmable electronic controller designed

specifically for the application and precise control

of Dunham-Bush Rotary Screw compressor

chillers.

The controller board is provided with a set of

terminals that connect to various devices such as

temperature sensors, pressure and current

transducers, solenoid valves, compressors and

fans contactors, control relays etc. Three sizes of

controller boards are provided to handle different

number of input and output requirements: DB3-S

small, DB3-M medium and DB3-L large board.

The unit algorithm program and operating

parameters are stored in FLASH-MEMORY that

does not require a back-up battery. The program

can be loaded through PC or programming key.

Vision 2020i controller is equipped with a user

friendly terminal with a semi-graphic display and

dedicated keys that provides easy access to the

unit operating conditions, control set points and

alarm history.

Each unit’s controller can be configured and

connected to the local DBLAN network that allows

multiple units sequencing control without

additional hardware. The DBLAN is local area

network made up of several chillers’ controller.

Display and User Terminal

The Vision 2020i controller is designed to work

with a user friendly back-lit 132 by 64 pixels

DBG1 Semi-Graphic Display panel connected

with the controller through a telephone cable. The

terminal allows carrying out of all program

operations and also allows the unit working

conditions, compressor run times and alarm

history to be displayed. Set points and other

parameters can be modified via the user terminal.

The display has an automatic self-test of the

controller on system start-up. Multiple messages

will be displayed automatically by scrolling from

each message to the next. All of these messages

are spelled out in English on the display terminal.

There are 15 dedicated buttons to enable the user

to access information, based on the security level

of the password. For more detail operation of the

DBG1 Display Terminal, please refer to the UnitOperation Manual.

Easily accessible measurements include:

Leaving chilled water temperature

Entering chilled water temperature

Compressor discharge temperature

Leaving chiller water temperature derivative

Evaporator Pressure

Condenser Pressure

Compressor amp draw of each compressor

Compressor elapsed run time of eachcompressor

Compressor starts status

Oil level sensor status

Water temperature reset value

Water flow switch status

External start/stop command status

Optional ambient temperature is available. With

this option the operator can quickly and

accurately read all significant temperatures and

eliminate the need for thermometers. Voltmeter isalso offered as an optional feature.

Capacity Control

Leaving chilled water temperature control is

accomplished by entering the water temperature

setpoint and placing the controller in automatic

control. The unit will monitor all control functions

and move the slide valve to the required operating

position. The compressor ramp (loading) cycle is

programmable and may be set for specific

building requirements. Remote adjustment of theleaving chilled water setpoint is accomplished

either through direct BMS protocols connection to


6/28

- 6 -

UNIT FEATURES

the controller communication ports, or from an

external hardwired control signal from BMS to

supply a chilled water reset 4 to 20mA analoginput signal. Remote reset of compressor current

limiting function may be accomplished in a similar

fashion.

System Control

The unit may be started or stopped manually, or

through the use of an external signal from a

Building Automation System. In addition, the

controller may be programmed with seven-day

operating cycle or other Dunham-Bush control

packages may start and stop the system through

inter-connecting wiring.

System Protection

The following system protection controls will

automatically act to ensure system reliability:

Low suction pressure

High discharge pressure

Freeze protection

Low differential pressure

Low oil level

Compressor run error

Power loss

Chilled water flow loss

Sensor error

Compressor over current

Compressor Anti-recycle

The controller can retain up to 99 alarm

conditions complete with time of failure togetherdata stamping on critical sensor readings in an

alarm history. This tool will aid service technicians

in troubleshooting tasks enabling downtime and

nuisance trip-outs to be minimized.

Remote Monitor ing

Vision 2020i controller can be completed with an

optional RS485 communications card and

NETVISOR software for remote monitoring and

controlled from a PC terminal and optional phone

modem.

With various optional add-on cards the

Vision2020i controller can also be interfaced

directly to the Building Management System

(BMS) with the standard communication protocols

using MODBUS, LONWORKS, BACNET MSTP

as well as over IP.

This sophisticated feature makes servicing easier

and more convenient to the system. The

controller as standard is additionally equipped

with history files which can be used to take logs

and which may be retrieved via the phone modemor internet connection periodically. Now owners of

multiple buildings have a simple and inexpensive

method of investigating potential problems quickly

and in a highly cost effective manner.

REFRIGERATION CYCLE

The refrigerant management system, is shown in

the refrigerant cycle diagram below.

Liquid refrigerant enters the flooded evaporatoruniformly where it absorbs heat from water

flowing through the evaporator tubes. The

vaporized refrigerant is then drawn into the

suction port of the compressor where the

compression begins.

This partially compressed gas is then combined

with additional gas from the flash economizer as

the vapor injection port at an intermediate

pressure is exposed to each interlobe space.

Compressed gaseous refrigerant is thendischarged into the integral oil separator where

oil, which is contained in the refrigerant vapor, is

removed and returned to the oil sump.

High pressure superheated refrigerant is then

discharged into the condenser, where air is drawn

across the condenser by propeller fans which cool

and condense the refrigerant. This liquid

refrigerant then passes through the first

expansion device and into the flash economizer

where flash gas and liquid refrigerant are

separated.


7/28

- 7 -

UNIT FEATURES

The flash gas is drawn into the vapor injection port

of the compressor. The remaining liquid

refrigerant then passes through a secondexpansion device which reduces the pressure

further and it is introduced into the bottom of the

flooded evaporator via an integral distributor.

By removing the flash gas from the flash

economizer at an intermediate pressure, the

enthalpy of the refrigerant flowing into the

evaporator is reduced. This increases the

refrigeration effect and improves the efficiency of

the refrigeration cycle.

Refrigerant flow into and out of the flasheconomizer is controlled by modulating valves

which eliminate the energy wasting hot gas

bypass effect inherent with fixed orifices.

PART-LOAD PERFORMANCE

Through the use of flash economizer modulating

flow control and multiple compressors, Dunham-

Bush air cooled chillers have some of the best

part-load performance characteristics in the

industry when measured in accordance with AHRIStandard 550/590-2003.

In most cases, actual building system loads are

significantly less than full load design conditions,

therefore chillers operate at part load most of the

time.

Dunham-Bush air cooled chillers combine the

efficient operation of multiple compressors with an

economizer cycle and advanced controller to yield

the best total energy efficiency and significant

operating saving under any load.

When specifying air conditioning equipment, it is

important to consider the system load

characteristics for the building application. In a

typical city, the air conditioning load will vary

according to changes in the ambient temperature.

Weather data compiled over many years will

predict the number of hours that equipment will

operate at various load percentages.


8/28


9/28

- 9 -

TYPICAL SEQUENCE OF OPERATION

The Dunham-Bush air cooled water chiller

depends mainly on its on-board controller for

control. Operation described is for a two-compressor units and is very similar for single

compressor units.

For initial start-up, the following conditions must

be met:

Power supply to unit energized.

Unit circuit breakers in the ‘on’ position.

Control power switch ‘on’ for at least 15

minutes. Compressor switches ‘on’.

Reset pressed on controller keypad.

Chilled water pump running and chilled water

flow switch made.

Leaving chilled water temperature at least 2°F

[1.1°C] above setpoint.

All safety conditions satisfied.

After all above conditions are met, the controller

will call for the lead compressor to start. The

compressor 15-minute anti-recycle timer is

initiated at compressor start.

The controller monitors compressor amps, volts,

leaving water temperature and suction and

discharge pressures. The compressor and cooling

capacity is controlled by pulsed signals to load

and unload solenoid valves on the compressor.

When the compressor starts, it is fully unloaded,

reducing about 25% of its full load capacity. As

the computer gives it load signals, capacity

gradually increases. The rate of compressor

loading is governed by ramp control which isadjustable in the computer.

The computer responds to leaving chilled water

temperature and its rate of change which is

proportional and derivative control. If leaving

chilled water temperature is within the deadband

(+/-0.8°F [0.5°C] from setpoint), no load or unload

commands are given. If chilled water temperature

is above deadband, the computer will continue

loading the compressor until a satisfactory rate of

decline is observed. If leaving chilled water

temperature is below the deadband, the

compressor is commanded to unload. Thus the

compressor capacity is continuously modulated to

match applied load and hold leaving chilled water

temperature at setpoint.

If the applied load is greater than one compressor

can handle, it will load fully and then the controller

will call for a second compressor. After one

minute, the second compressor will start in the

same manner as the first. Then both compressors

will be commanded to adjust load to 50%. They

are gradually loaded up together until the applied

load is satisfied. In this way the two compressors

share the load equally.

If the applied load decreases to the point that both

compressors are running at about 40% capacity,the computer shuts down the lag compressor and

loads the remaining compressor to about 80%. If

applied load decreases further, the remaining

compressor unloads proportionately. If applied

load decreases to less than the minimum capacity

of one compressor, the leaving chilled water

temperature will decline to 2°F [1.1°C] below

setpoint, at which time the lead compressor will

shut down. It will restart automatically if leaving

chilled water temperature rises to 2°F [1.1°C]

above setpoint and both 15 minute anti-recycle

and one minute start delay timers are satisfied.

During start-up operation, the computer monitors

the difference between discharge and suction

pressures to ensure that minimum of 30psi

[2bar] differential is available for compressor

lubrication. If the difference falls below a minimum

of 30psi [2bar], the computer closes refrigerant

flow control valves, starving the evaporator,

causing evaporator pressure to drop, increasing

differential pressure. This is especially helpful at

startup, when warm chilled water and low ambient

temperature would cause a low head situation.

This feature is called EPCAS: Evaporator

Pressure Control at Startup. It is one of several

proactive control features of the controller which

overcome potential problems while continuing

operation.

Two additional proactive features are low suction

and high discharge pressure override. If operating

pressures approach trip level, compressors areunloaded as necessary to continue operation.


10/28

- 10 -

APPLICATION DATA

Low Ambient Operation / FreezeProtection

If unit is required to operate below 20°F [-7°C],optional head pressure control is required.

Immersion heater and circulating pump need to

be provided to be in operation when the chiller is

not operating. Glycol is recommended for added

protection. If wind in area is over 5 mph [8 kph], a

wind barrier is recommended.

Desuperheaters

A hot gas desuperheater can be factory suppliedfor field installation. Suitable fittings in refrigerantlines with shut off valves can be supplied. Consultfactory for further details.

Water Circuit

Constant water flow required with a minimum of 3USgal per TR [3.3 liters / kW°] increasing up to 10

USgal [11 liters] for process, low load applicationswith small temperature ranges and/or vastlyfluctuating load conditions.

Glycol Freeze Protection

If the chiller or fluid piping may be exposed to

temperatures below freezing, glycol protection is

recommended. The re-commended protection is

10°F [5.6°C] below the minimum ambient

temperature. Use only glycol solutions approved

for heat exchanger duty. The use of automotive

anti-freeze is not recommended because they

have short-lived inhibitors and fouling of the

vessels will occur. If the equipment is exposed to

freezing temperature and not being used, the

vessels and piping should be drained.

The use of glycol causes a performance derate asshown below which needs to be included in theunit selection procedure.

Ethylene Glycol

% E. G.By Weight

Freeze Point C1Capacity Factor

K1kW Rate

G1Flow Factor

P1P.D. Factor°F °C

10 26.2 -3.2 0.995 0.998 1.019 1.050

15 22.4 -5.3 0.991 0.997 1.030 1.083

20 17.8 -7.9 0.988 0.996 1.044 1.121

25 12.6 -10.8 0.984 0.995 1.060 1.170

30 6.7 -14.1 0.981 0.994 1.077 1.219

35 0.0 -17.8 0.977 0.992 1.097 1.275

40 -10.0 -23.3 0.973 0.991 1.116 1.331

45 -17.5 -27.5 0.968 0.990 1.138 1.398

50 -28.9 -33.8 0.964 0.989 1.161 1.466

Propylene Glycol

% P. G.

By Weight

Freeze Point C2

Capacity Factor

K2

kW Rate

G2

Flow Factor

P2

P. D. Factor°F °C

10 26.1 -3.3 0.988 0.994 1.005 1.019

15 22.8 -5.1 0.984 0.992 1.008 1.031

20 19.1 -7.2 0.978 0.990 1.010 1.051

25 14.5 -9.7 0.970 0.988 1.015 1.081

30 8.9 -12.8 0.962 0.986 1.021 1.120

Correction Factor - Elevation

Elevation above Sea Level CapacityCorrection

Factor

kWCorrection

FactorFeet Meters Factor

0 0 1.00 1.002000 600 0.99 1.01

4000 1200 0.98 1.02

6000 1800 0.97 1.03

Correction Factor - FF

Fouling Factor CapacityCorrection

Factor

kWCorrection

Factorhr.ft².°F/BTU m².°C/kW

0.00010 0.018 1.000 1.0000.00025 0.044 0.990 0.995

0.00050 0.088 0.970 0.990


11/28

- 11 -

PHYSICAL SPECIFICATIONS

Model AFHX 75-6SR 80T-6SR 90T-6SR 100-6SR 115-6SR

Unit Nominal Capacity TR[kW] 70 [246] 74 [260] 84 [295] 88 [311] 103 [362]

Unit Nominal Power Input kW 86 92 104 110 128

COMPRESSOR

Model (Qty) HX 1512 (1) HX 1309 (2) HX 1311 (2) HX 1709 (1) HX 1711 (1)

RPM 3550 3550 3550 3550 3550

Min. % Unit Capacity 25% 12.5% 12.5% 25% 25%

EVAPORATOR

Model (Qty) B1R (1) B1R (1) C1R (1) C1R (1) D1R (1)

Water Connector inches[ mm] 5 [127] 5 [127] 5 [127] 5 [127] 6 [152]

Nominal Water Flow / Pressure DropUSgpm/ ft.wg[m³/hr/ kPa]

168.7/ 9.3[38.3/ 27.8]

177.3/ 10.2[40.3/ 30.5]

201.2/ 8.4[45.7/ 25.1]

212.3/ 9.3[48.2/ 27.8]

247.1/ 7.4[56.1/ 22.1]

Min/ Max Water Flow USgpm[m³/hr] 63.0/ 313.0[14.3/ 71.1]

63.0/ 313.0[14.3/ 71.1]

79.0/ 396.5[17.9/ 90.0]

79.0/ 396.5[17.9/ 90.0]

105.0/ 523.0[23.8/ 118.7]

Min/ Max Water Pressure Drop ft.wg[ kPa] 1.6/ 28.3[4.8/ 84.6]

1.6/ 28.3[4.8/ 84.6]

1.6/ 28.7[4.8/ 85.8]

1.6/ 28.7[4.8/ 85.8]

1.6/ 28.5[4.8/ 85.2]

CONDENSER

Coil Rows Deep/ Total Face Area ft²[m²] 3/ 121.9 [11.3] 3/ 121.9 [11.3] 4/ 121.9 [11.3] 4/ 121.9 [11.3] 4/ 162.6 [15.1]

No. Of Fan 6 6 6 6 8

Fan Diameter (Qty) inches[ mm] 31.5 [800](6) 31.5 [800](6) 31.5 [800](6) 31.5 [800](6) 31.5 [800](8)

Motor kWi (Qty) 2(6) 2(6) 2(6) 2(6) 2(8)

FLA, AMP (Qty) 3.8(6) 3.8(6) 3.8(6) 3.8(6) 3.8(8)

Total Air Flow cfm[m³/hr]76734

[130386]74466

[126532]72954

[123963]72954

[123963]101304

[172136]

Min. Operating Ambient °F[°C] 45 [7.2] 45 [7.2] 45 [7.2] 45 [7.2] 45 [7.2]

ELECTRICAL

Nominal Voltage 460/3/60 460/3/60 460/3/60 460/3/60 460/3/60

Unit RLA A 140 151 167 173 200

Unit Max. Inrush A 231 195 203 266 312

GENERAL

Unit Length inches[mm] 150 [3810] 150 [3810] 150 [3810] 150 [3810] 192 [4877]

Unit Width inches[mm] 88 [2235] 88 [2235] 88 [2235] 88 [2235] 88 [2235]

Unit Height inches[mm] 87.5 [2222] 87.5 [2222] 87.5 [2222] 87.5 [2222] 87.5 [2222]

Shipping Weight lbs[kg] 8526 [3867] 9063 [4111] 9601 [4355] 9322 [4228] 10919 [4953]

Operating Weight lbs[kg] 8641 [3920] 9179 [4164] 9749 [4422] 9470 [4295] 11112 [5040]

Operating Charge R134a lbs[k g] 205 [93] 216 [98] 245 [111] 260 [118] 302 [137]

Note: Nominal capacity is based on evaporator LWT 44°F and condenser ambient 95°F, actual capacity depends on the specified operatingconditions.


12/28

- 12 -

PHYSICAL SPECIFICATIONS

Model AFHX 125T-6SR 135-6SR 150-6SR 150T-6SR 175T-6SR 190-6SR

Unit Nominal Capacity TR [kW] 110 [387] 121 [427] 132 [466] 137 [482] 158 [556] 171 [603]

Unit Nominal Power Input kW 138 150 162 172 192 213

COMPRESSOR

Model (Qty) HX 1509 (2) HX 1811 (1) HX 1813 (1) HX 1512 (2) HX 1709 (1)HX 1512 (1)

HX 1816 (1)

RPM 3550 3550 3550 3550 3550 3550

Min. % Unit Capacity 12.5% 25% 25% 12.5% 12.5% 25%

EVAPORATOR

Model (Qty) D2R (1) D2R (1) J1R (1) J1R (1) K1R (1) K2R (1)

Water Connector inches[ mm] 6 [152] 6 [152] 6 [152] 6 [152] 6 [152] 6 [152]

Nominal Water Flow / Pressure DropUSgpm / ft.wg [m³/hr / kPa]

264.3/ 6.8[60.0/ 20.3]

291.6/ 8.1[66.2/ 24.2]

318.0/ 11.2[72.2/ 33.5]

329.3/ 11.9[74.8/ 35.6]

380.1/ 13.3[86.3/ 39.8]

411.7/ 13.0[93.5/ 38.9]

Min/ Max Water Flow USgpm[m³/hr] 117.0/ 587.0[26.6/ 133.2]

117.0/ 587.0[26.6/ 133.2]

117.0/ 588.0[26.6/ 133.4]

117.0/ 588.0[26.6/ 133.4]

128.0/ 640.0[29.1/ 145.3]

142.0/ 705.0[32.2/ 160.0]

Min/ Max Water Pressure Drop ft.wg[ kPa] 1.6/ 28.8[4.8/ 86.1]

1.6/ 28.8[4.8/ 86.1]

1.9/ 33.8[5.7/ 101.1]

1.9/ 33.8[5.7/ 101.1]

1.9/ 33.9[5.7/ 101.4]

1.9/ 34.3[5.7/ 102.6]

CONDENSER

Coil Rows Deep/ Total Face Area ft²[m²] 4/ 162.6 [15.1] 4/ 162.6 [15.1] 4/ 188.2 [17.5] 4/ 188.2 [17.5] 4/ 235.3 [21.9] 4/ 235.3 [21.9]

No. Of Fan 8 8 8 8 10 10

Fan Diameter (Qty) inches[ mm] 31.5 [800](8) 31.5 [800](8) 31.5 [800](8) 31.5 [800](8) 31.5 [800](10) 31.5 [800](10)

Motor kWi (Qty) 2(8) 2(8) 2(8) 2(8) 2(10) 2(10)

FLA, AMP (Qty) 3.8(8) 3.8(8) 3.8(8) 3.8(8) 3.8(10) 3.8(10)

Total Air Flow cfm[m³/hr] 97272[165285]

97272[165285]

103236[175419]

101388[172278]

126735[215348]

129045[219273]

Min. Operating Ambient °F[°C] 45 [7.2] 45 [7.2] 45 [7.2] 45 [7.2] 45 [7.2] 45 [7.2]

ELECTRICAL

Nominal Voltage 460/3/60 460/3/60 460/3/60 460/3/60 460/3/60 460/3/60

Unit RLA A 224 229 243 264 335 319

Unit Max. Inrush A 294 335 497 356 426 536

GENERAL

Unit Length inches[mm] 192 [4877] 192 [4877] 202.5 [5144] 192 [4877] 234 [5944] 234 [5944]

Unit Width inches[mm] 88 [2235] 88 [2235] 88 [2235] 88 [2235] 88 [2235] 88 [2235]

Unit Height inches[mm] 87.5 [2222] 87.5 [2222] 96.5 [2451] 96.5 [2451] 96.5 [2451] 96.5 [2451]

Shipping Weight lbs[kg] 12034 [5458] 11495 [5214] 12329 [5593] 12896 [5850] 15361 [6968] 14579 [6613]

Operating Weight lbs[kg] 12246 [5555] 11708 [5311] 12581 [5707] 13148 [5964] 15641 [7095] 14882 [6750]

Operating Charge R134a lbs[k g] 322 [146] 355 [161] 388 [176] 401 [182] 483 [219] 522 [237]

Note: Nominal capacity is based on evaporator LWT 44°F and condenser ambient 95°F, actual capacity depends on the specified operatingconditions.


13/28

- 13 -

PERFORMANCE DATA

LWT°F

Model AFHX

Ambient Temperatu re, °F

85.0 95.0 105.0 115.0

TR kW° kWI TR kW° kWI TR kW° kWI TR kW° kWI

40.0

75-6SR 67.7 238.0 63.2 65.0 228.4 72.8 61.6 216.5 84.9 57.3 201.3 100.2

80T-6SR 70.5 247.9 68.7 68.2 240.0 79.0 65.0 228.4 92.0 60.6 213.2 108.3

90T-6SR 80.7 283.6 78.4 77.5 272.4 90.6 73.3 257.9 105.5 68.2 239.7 125.5

100-6SR 85.5 300.8 83.9 81.7 287.3 97.0 77.2 271.4 113.4 71.7 252.2 135.1

115-6SR 99.3 349.1 95.6 95.1 334.6 110.3 90.0 316.4 128.8 83.7 294.2 153.3

125T-6SR 106.0 372.9 104.4 101.7 357.7 120.3 96.4 338.9 140.3 89.6 315.1 166.7

135-6SR 117.5 413.2 114.3 112.1 394.4 132.2 105.8 372.2 154.8 98.2 345.5 184.6

150-6SR 128.3 451.3 124.5 122.4 430.4 144.7 115.3 405.7 169.2 106.9 375.9 202.4

150T-6SR 132.7 466.8 132.5 126.7 445.6 153.5 119.4 419.9 180.0 110.6 389.1 215.9

175T-6SR 152.8 537.5 147.3 146.4 514.7 169.9 138.4 486.6 198.6 128.8 452.9 236.4

190-6SR 166.1 584.2 165.1 158.3 556.7 190.7 149.1 524.3 225.5 137.7 484.3 270.2

42.0

75-6SR 70.3 247.3 63.3 67.5 237.4 73.0 64.1 225.5 85.0 59.8 210.2 100.3

80T-6SR 73.2 257.5 69.1 71.0 249.6 79.2 67.6 237.7 92.3 63.3 222.5 108.5

90T-6SR 83.9 294.9 78.8 80.6 283.3 90.8 76.3 268.5 105.9 71.2 250.3 125.5

100-6SR 88.8 312.4 84.3 85.0 298.9 97.3 80.4 282.7 113.9 74.9 263.5 135.0

115-6SR 103.1 362.7 96.0 98.9 347.8 110.7 93.7 329.6 129.5 87.3 307.1 153.4

125T-6SR 110.1 387.1 104.8 105.8 371.9 120.7 100.4 353.1 140.7 93.5 328.9 166.8

135-6SR 122.0 429.1 114.8 116.7 410.3 132.7 110.3 387.8 155.6 102.6 360.7 184.5

150-6SR 133.3 468.8 125.0 127.3 447.6 144.7 120.1 422.5 169.8 111.7 392.7 202.7

150T-6SR 137.9 485.0 133.1 131.8 463.5 154.0 124.4 437.4 180.6 115.6 406.6 215.5

175T-6SR 158.8 558.4 147.8 152.2 535.3 170.5 144.1 506.8 199.6 134.4 472.8 235.6

190-6SR 172.6 607.0 165.8 164.7 579.2 190.7 155.4 546.5 226.6 143.9 506.1 270.4

44.0

75-6SR 73.0 256.9 63.4 70.2 247.0 73.6 66.7 234.7 86.0 62.4 219.5 100.4

80T-6SR 76.1 267.5 69.3 73.8 259.5 79.9 70.3 247.3 92.9 66.0 232.1 108.8

90T-6SR 87.0 306.1 79.0 83.8 294.5 91.6 79.5 279.7 106.3 74.3 261.2 125.3

100-6SR 92.2 324.3 84.4 88.4 310.8 98.2 83.8 294.5 114.2 78.2 275.1 136.0

115-6SR 107.1 376.6 96.1 102.8 361.7 111.7 97.6 343.2 129.9 91.2 320.7 153.1

125T-6SR 114.3 402.0 105.0 110.0 386.8 121.8 104.5 367.6 141.0 97.7 343.5 166.5

135-6SR 126.7 445.6 114.9 121.4 426.8 133.8 115.0 404.3 155.5 107.2 376.9 185.3

150-6SR 138.5 487.0 125.7 132.4 465.5 146.5 125.3 440.7 170.1 116.7 410.3 203.1

150T-6SR 143.3 503.8 133.9 137.1 482.0 156.0 129.6 455.9 181.0 120.8 424.8 216.5

175T-6SR 164.9 579.9 148.0 158.2 556.4 172.0 150.1 528.0 200.3 140.3 493.6 236.8

190-6SR 179.3 630.5 166.5 171.4 602.7 192.9 162.0 569.6 227.5 150.4 529.0 270.8

Notes: 1.) Ratings based on 10°F water range in evaporator and .0001 hr.ft².°F/BTU fouling factor.

2.) Interpolation between ratings is permissible but extrapolation is NOT.3.) kWI is for compressor input.4.) Unit is running on part load for ambient temperature 115°F and above due to current limiter.


14/28

- 14 -

PERFORMANCE DATA

LWT°F

Model AFHX

Ambient Temperatu re, °F

85.0 95.0 105.0 115.0

TR kW° kWI TR kW° kWI TR kW° kWI TR kW° kWI

46.0

75-6SR 75.8 266.4 63.8 72.9 256.5 74.0 69.5 244.3 85.9 65.1 228.8 101.3

80T-6SR 79.0 277.7 69.3 76.6 269.4 80.3 73.1 257.2 92.9 68.7 241.7 109.0

90T-6SR 90.3 317.7 79.4 87.0 305.8 92.0 82.8 291.2 106.5 77.5 272.4 125.9

100-6SR 95.8 336.9 84.9 91.8 323.0 98.6 87.2 306.8 114.9 81.6 287.0 135.8

115-6SR 111.2 391.1 96.6 106.9 375.9 112.1 101.6 357.4 130.5 95.1 334.6 153.8

125T-6SR 118.6 417.2 105.5 114.2 401.7 122.4 108.8 382.5 141.4 101.8 358.0 167.2

135-6SR 131.6 462.8 115.5 126.1 443.3 134.4 119.6 420.5 156.9 111.8 393.1 184.8

150-6SR 143.7 505.5 125.8 137.6 484.0 146.8 130.4 458.5 171.1 121.7 428.1 202.3

150T-6SR 148.8 523.3 134.1 142.4 500.9 156.2 135.0 474.7 182.0 126.0 443.0 215.7

175T-6SR 171.2 602.0 148.9 164.4 578.2 172.9 156.2 549.5 200.3 146.3 514.4 237.1

190-6SR 186.1 654.6 167.4 178.1 626.5 192.0 168.6 593.1 228.2 157.0 552.1 270.1

48.0

75-6SR 78.6 276.4 64.0 75.6 265.8 74.0 72.1 253.6 86.6 67.6 237.7 101.9

80T-6SR 81.8 287.6 69.8 79.4 279.4 80.3 76.0 267.1 93.7 71.4 251.3 110.4

90T-6SR 93.6 329.3 79.9 90.2 317.1 92.2 85.9 302.2 107.5 80.5 283.0 126.5

100-6SR 99.3 349.1 85.6 95.2 334.9 98.9 90.5 318.4 115.7 84.8 298.2 136.3

115-6SR 115.2 405.3 97.5 110.8 389.8 112.3 105.5 370.9 131.2 98.8 347.4 154.4

125T-6SR 123.1 432.8 106.3 118.4 416.6 122.4 112.9 397.0 143.4 105.8 371.9 168.6

135-6SR 136.4 479.7 117.1 130.8 459.8 135.0 124.2 436.7 158.0 116.2 408.6 186.7

150-6SR 149.0 524.0 127.5 142.8 502.2 147.1 135.4 476.1 172.4 126.6 445.3 204.3

150T-6SR 154.3 542.5 135.6 147.8 519.7 156.6 140.2 492.9 183.3 131.0 460.9 217.9

175T-6SR 177.5 624.2 150.0 170.5 599.7 173.1 162.2 570.3 202.3 152.0 534.6 238.0

190-6SR 193.0 678.7 168.8 184.8 649.9 193.5 175.1 615.9 229.8 163.4 574.6 273.1

50.0

75-6SR 81.5 286.6 64.6 78.5 276.0 74.2 74.9 263.5 86.8 70.3 247.3 102.0

80T-6SR 84.9 298.5 70.2 82.4 289.9 80.7 78.9 277.4 94.1 74.3 261.2 110.6

90T-6SR 97.1 341.5 80.7 93.6 329.3 92.5 89.3 314.1 108.1 83.8 294.5 127.3

100-6SR 103.0 362.3 86.2 98.9 347.8 99.0 94.1 330.9 116.3 88.4 310.8 137.0

115-6SR 119.6 420.5 98.2 115.1 404.7 112.9 109.6 385.5 132.0 102.9 362.0 154.9

125T-6SR 127.6 448.6 107.3 123.0 432.4 122.8 117.3 412.6 143.8 110.1 387.1 168.6

135-6SR 141.5 497.5 117.4 135.8 477.7 135.4 129.1 453.9 158.9 121.1 425.8 187.1

150-6SR 154.6 543.8 127.9 148.3 521.7 147.8 140.8 495.2 174.2 132.0 464.2 205.0

150T-6SR 160.0 562.7 136.0 153.5 539.9 157.1 145.7 512.4 185.5 136.6 480.4 218.4

175T-6SR 184.1 647.3 151.3 177.1 622.9 174.1 168.5 592.8 203.5 158.4 557.1 239.3

190-6SR 200.2 704.2 169.3 192.0 675.1 195.0 182.2 640.7 231.7 170.3 599.1 273.4

Notes: 1.) Ratings based on 10°F water range in evaporator and .0001 hr.ft².°F/BTU fouling factor.

2.) Interpolation between ratings is permissible but extrapolation is NOT.3.) kWI is for compressor input.4.) Unit is running on part load for ambient temperature 115°F and above due to current limiter.


15/28

- 15 -

DIMENSIONAL DATA

AFHX 75-6SR, 100-6SR

AFHX 80T-6SR, 90T-6SR

AFHX 115-6SR, 135-6SR

Note : All dimensions are in inches[mm].


16/28

- 16 -

DIMENSIONAL DATA

AFHX 125T-6SR, 150T-6SR

AFHX 150-6SR



17/28

- 17 -

DIMENSIONAL DATA

AFHX 175T-6SR

AFHX 190-6SR



18/28

- 18 -

FLOOR LOADING DIAGRAM

a.) POINT LOAD LOCATION – inches[mm]

Model AFHX A Dim. B Dim. C Dim. D Dim. E Dim.

75-6SR 86[2184] 18[457] 57[1448] 57[1448] 18[457]

80T-6SR 86[2184] 18[457] 57[1448] 57[1448] 18[457]

90T-6SR 86[2184] 18[457] 57[1448] 57[1448] 18[457]

100-6SR 86[2184] 18[457] 57[1448] 57[1448] 18[457]

115-6SR 86[2184] 18[457] 78[1981] 78[1981] 18[457]

125T-6SR 86[2184] 18[457] 78[1981] 78[1981] 18[457]

135-6SR 86[2184] 18[457] 78[1981] 78[1981] 18[457]

150-6SR 86[2184] 18[457] 83-1/4[2115] 83-1/4[2115] 18[457]

150T-6SR 86[2184] 18[457] 78[1981] 78[1981] 18[457]

175T-6SR 86[2184] 18[457] 99[2515] 99[2515] 18[457]

190-6SR 86[2184] 18[457] 99[2515] 99[2515] 18[457]

b.) POINT LOAD DATA – lbs [kg]

Model

AFHX

Pos.

#1

Pos.

#2

Pos.

#3

Pos.

#4

Pos.

#5

Pos.

#6

Total Operating

Weight

75-6SR 1297 [588] 1464 [664] 1630 [739] 1465 [665] 1416 [642] 1368 [621] 8641 [3919]

80T-6SR 1633 [741] 1578 [716] 1523 [691] 1462 [663] 1482 [672] 1501 [681] 9179 [4164]

90T-6SR 1737 [788] 1675 [760] 1612 [731] 1550 [703] 1575 [714] 1599 [725] 9749 [4422]

100-6SR 1415 [642] 1614 [732] 1813 [822] 1598 [725] 1543 [700] 1487 [674] 9470 [4296]

115-6SR 1607 [729] 1849 [839] 2091 [948] 1795 [814] 1855 [841] 1915 [869] 11112 [5040]

125T-6SR 2169 [984] 2094 [950] 2020 [916] 1819 [825] 1987 [901] 2156 [978] 12246 [5555]

135-6SR 1700 [771] 1954 [886] 2208 [1002] 1886 [855] 1949 [884] 2011 [912] 11708 [5311]

150-6SR 1794 [814] 2102 [953] 2411 [1094] 2057 [933] 2091 [948] 2125 [964] 12581 [5707]

150T-6SR 2323 [1054] 2258 [1024] 2192 [994] 1994 [904] 2125 [964] 2256 [1023] 13148 [5964]

175T-6SR 3046 [1382] 2787 [1264] 2528 [1147] 2145 [973] 2427 [1101] 2708 [1228] 15641 [7095]

190-6SR 2056 [933] 2257 [1024] 2458 [1115] 2715 [1232] 2704 [1227] 2692 [1221] 14882 [6750]


19/28

- 19 -

DIMENSIONAL CLEARANCE

SPACE REQUIREMENTS

Single Pit (See Note 2)

Double Pit (See Note 2)

Multi Pit

Corner Wall

Notes:

1.) All dimensions are minimal, unlessotherwise noted.

2.) Pit installations are not re-commended. Re-circulation of hotcondenser air in combination withsurface air turbulence cannot bepredicted. Hot air re-circulation willseverely affect unit efficiency (EER)and can cause high pressure or fanmotor temperature trips. Dunham-Bush will not be responsible for

ducting fans to a higher level toalleviate the above mentionedconditions.


20/28

- 20 -

1

10

100

10 100 1000

P R E S S U R E D R O P - f t . w g .

WATER FLOW RATE - USgpm

1

10

100

1000

10 100 1000

P R E S S U R E

D R O P - k P a

WATER FLOW RATE - m³/hr

EVAPORATOR WATER PRESSURE DROP

IMPERIAL UNITS

S. I. UNITS

SOUND PRESSURE DATA

ModelOctave Band (Hz)

TotaldB (A)63 125 250 500 1K 2K 4K 8K

AFHX 75-6SR 45 44 50 52 57 55 51 43 61

AFHX 80T-6SR 46 45 51 53 58 56 51 44 62

AFHX 90T-6SR 46 45 51 53 58 56 51 44 62

AFHX 100-6SR 48 46 52 53 60 57 52 44 63

AFHX 115-6SR 48 47 53 54 61 58 53 45 64

AFHX 125T-6SR 47 46 52 54 59 57 52 45 63

AFHX 135-6SR 50 49 54 55 63 60 55 46 66

AFHX 150-6SR 51 49 55 55 63 60 55 46 66

AFHX 150T-6SR 48 47 52 54 60 57 53 45 63

AFHX 175T-6SR 49 48 54 55 61 59 54 46 65

AFHX 190-6SR 51 49 55 56 63 61 55 46 67

Note: Unit Sound Pressure Level (Lp) @ 33 ft [10m] (free field), ± 2 dB tolerance.

AFHX 75-6SR AFHX 80T-6SR

AFHX 90T-6SR AFHX 100-6SR

AFHX 115-6SR AFHX 150-6SR

AFHX 150T-6SR


AFHX 175T-6SR

AFHX 190-6SR

AFHX 75-6SR AFHX 80T-6SR


AFHX 115-6SR AFHX 150-6SR

AFHX 150T-6SR




21/28

- 21 -

CONDENSER FAN

FAN POSITION NUMBER & CYCLING SEQUENCE

AFHX 75-6SR, 100-6SR,80T-6SR, 90T-6SR

AFHX 115-6SR, 135-6SR, 150-6SR,125T-6SR, 150T-6SR

BASE FANS 2, 4, 6 BASE FANS 2, 4, 6, 8

STAGE 1 1, 5 STAGE 1 1, 5

STAGE 2 3 STAGE 2 3, 7

AFHX 175T-6SR, 190-6SR

BASE FANS 2, 4, 6, 8, 10

STAGE 1 1, 5

STAGE 2 3, 7

STAGE 3 9

ELECTRICAL DATA

MODEL AFHX

COMPRESSOR DATA COND. FAN MOTOR DATA UNIT ELECTRICAL DATA

MODEL QTY RLA LRA QTY HP FLA FLA MCA MFS

75-6SR HX1512 1 107 625 6 2 3.8 130 157 250

80T-6SR HX1309 2 58 325 6 2 3.8 139 153 200

90T-6SR HX1311 2 67 325 6 2 3.8 157 174 200

100-6SR HX1709 1 143 730 6 2 3.8 166 202 300

115-6SR HX1711 1 162 845 8 2 3.8 192 233 350

125T-6SR HX1509 2 89 500 8 2 3.8 208 231 300

135-6SR HX1811 1 194 915 8 2 3.8 224 273 450

150-6SR HX1813 1 213 1400 8 2 3.8 243 297 500

150T-6SR HX1512 2 113 625 8 2 3.8 256 285 350

175T-6SRHX1709HX1512

11

142109

730625

10 2 3.8 289 325 450

190-6SR HX1816 1 281 1495 10 2 3.8 319 389 600

Note: MCA - Minimum Circuit Ampacity MFS - Maximum Fuse Size RLA - Running Load AmpsFLA – Full Load Amps LRA - Locked Rotor Amps


22/28


23/28

- 23 -

TYPICAL WIRING SCHEMATIC


24/28

- 24 -

Ω

Ω



25/28

- 25 -



26/28

- 26 -

GUIDE SPECIFICATIONS

1. The contractor shall in accordance with the plans,

furnish and install _____________ Dunham-Bush

_______________ packaged liquid chiller(s). Theunit(s) shall be completely factory packaged

including rotary screw compressor(s), evaporator,

condenser, and controller control center. The

packaged chiller shall be factory assembled,

charged and tested with a full operating refrigerant

and oil charge. The refrigerant type shall be R134a.

2. Capacity of each chiller shall be not less than

_________________ TR (kW output) cooling

_____________ USgpm (liters/min.) of water from

__________ °F[°C] to _________ °F[°C]. Power

input requirements for the unit(s), incorporating all

appurtenances necessary for unit operation,

including but not limited to the control accessories

and oil pump or pumps, if required, shall not exceed

___________kW input at design conditions. The

unit shall be able to unload to _______% of cooling

(refrigeration) capacity when operating with leaving

chilled water and entering condenser water

temperature at full load design temperatures. The

unit shall be capable of continuous operation at this

point, with stable compressor operation, without the

use of hot gas bypass.

3. Heat transfer surfaces shall be selected to reflect

the incorporation of a fouling factor of 0.0001 hr.ft².

°F/BTU [0.000018m².°C/W] for the evaporator.

Water pressure drop at design conditions shall not

exceed ____________ feet of water through the

evaporator.

4. The packaged chiller shall be furnished with single-

stage direct connected positive displacement rotary

screw compressor(s) as required, of the oil injected

type, driven by a 3500 RPM (2900 RPM-50Hz)

motor. Each compressor shall include an integral oil

separation system, oil sump and oil filter. The oil

temperature shall be controlled during operation to

maintain proper oil temperatures throughout the

lubrication system. An electric oil heater shall be

supplied with each compressor to maintain oil

temperature during shutdown period. Each

compressor shall have a suction filter, suction

service valve and a discharge check valve.

Compressor capacity control shall be obtained by

an electrically initiated, hydraulically actuated slidevalve within each compressor housing. (Provide

isolation valves on all connections to compressor to

allow condenser to be used as a pump down

receiver.)

5. Evaporator vessels shall all be cleanable shell and

tube type with integral finned copper water tubes

mechanically expanded into heavy fixed steel tube

sheets. They are to be available in one, two or three

pass design as required on the drawings with

Victaulic connections. Flanges or stub out

connections optional. The shell side of the

evaporator is to have a single relief valve with

provision for refrigerant venting. Evaporators shall

be designed, constructed in accordance with the

ASME Code for Unfired Pressure Vessels. The

flooded evaporator shall have a built in distributor

for feeding refrigerant evenly under the tube bundle

to produce a uniform boiling action and baffle plates

shall be provided to ensure vapor separation. Water

headers are to be removable for tube cleaning. Vent

and drain plugs are to be provided in each head.

(All low temperature surfaces shall be factory

insulated.)

6. The flooded evaporator shall be fitted with an oil

recovery system. The oil recovery system will

ensure that the evaporator is operating at peak

efficiency at all times and provide optimal energy

efficiency during extended periods of part load.

Units without oil recovery systems mounted on the

evaporator will not be acceptable.

7. The condenser coil is to be constructed of copper

tubes and die formed aluminum fins having self-

spacing collars. Fins shall be mechanically bonded

to the tubes. An integral sub-cooling loop shall be

incorporated into the coil. Condenser divider baffles

shall fully separate each condenser fan section tocontrol the airflow to maintain proper head pressure

control. The condenser shall be sized for pump

down capacity.

8. To maximize energy efficiency, the packaged chiller

shall be equipped with a flash economizer cycle and

modulating refrigerant expansion devices.

Refrigerant vapor from the flash economizer shall

be fed back into an intermediate compressor stage,

reducing the enthalpy of the refrigerant and

increasing the net refrigeration effect of the

evaporator.


27/28

- 27 -

GUIDE SPECIFICATIONS

9 The fans shall be heavy duty, polypropylene blade,

direct drive propeller type. Motors shall be three

phase with internal overloads and are to bepermanently lubricated.

10. The packaged chiller shall be furnished with a

modulating refrigerant control system to optimize

efficiency and compressor protection. This

refrigerant control system will reduce the flow of

efficiency robbing refrigerant vapor in the

condenser from entering the evaporator at reduced

load by directly modulating a motorized refrigerant

valve in the liquid line entering the evaporator. In

addition, the refrigerant control system shall

measure the level of liquid refrigerant in theflooded evaporator and restrict refrigerant flow

entering the evaporator upon a rise in the level,

protecting the compressor from liquid slugging.

Fixed orifice control systems will not be

acceptable. (Hot gas bypass shall be factory

installed for operation below minimum percent of

unit capacity.)

11. The packaged chiller shall be equipped with

controller control. The control shall provide for

compressor loading based on leaving chilled water

temperature. It shall provide for high and low

refrigerant pressure protection, low oil level

protection, evaporator water freeze protection,

sensor error protection, and motor load control

(demand limiter) based on amp draw. Anti-recycle

protection shall also be provided. The controller

shall have a simple keypad accessed input system

and be complete with a two-line 80 character

alphanumeric display. Input shall be accomplished

through simple menu driven display screens, with

on-line help available by pressing a help button at

anytime during operation. The controller shallcontinuously monitor evaporator leaving water

temperature; evaporator and condenser pressure;

compressor amp draw; and refrigerant. The

controller shall be complete with all hardware and

software necessary to enable remote monitoring of

all data through the addition of only a simple,

phone modem and terminal. The controller shall be

complete with an RS232 "local" communications

port and an RS485 long distance differential

communications port. The controller shall also

accept a remote start and stop signal, 0 to 5VDC

chilled water temperature reset signal and (0 to

5VDC compressor current limit reset signal).

Terminal or PC with communication software

installed to enable remote monitoring.

12. The electrical control panel shall be wired to permitfully automatic operation during - initial start-up,

normal operation, and shutdown conditions. The

control system shall contain the following control

and safety devices:

MANUAL CONTROLS

Control circuit stop and start switches

Compressor enable switch

SAFETY CONTROLS

Solid state compressor motor starter overloads

(3 phase)

Low oil level optical sensor

High condenser pressure

Low evaporator pressure

Freeze protection

Chilled water flow loss

Under voltage phase failure relay

AUTOMATIC CONTROLS

Compressor motor increment contactors

Increment start timer

Anti-recycle timer

Oil sump heater interlock relays

REFRIGERANT CONTROLS

Motorized refrigerant flow control

Liquid refrigerant level sensor for evaporator

Compressor load and unload solenoid valves

INDICATOR LIGHTS

Power on

Compressor high oil temperature

Compressor motor overload

System common alarm

13. The control system shall be provided with an anti-

recycle device. The control shall limit compressor

starting to a minimum of 15 minutes between

starts.

14. The packaged chiller shall be furnished with unit

mounted reduced inrush starting system for each

compressor. The starters shall be factory mounted

and wired, with individual circuit breakers on

multiple compressor units. The unit shall be wired

so that the only field electrical connection to the

packaged chiller shall be to a single three-phasepower terminal.

Optional items in ( )


28/28

[email protected] dunham bush com

Africa

South Africa

No. 57 Sov ereign DriveRoute 21 Corporate ParkIrene, PretoriaSouth Africa

Tel: 27-12-345 4202Fax: 27-12-345 4203

Europe

United Kingdom

8 Downley Road,Havant, Hampshire,England PO9 2JD

Tel : 44-23-9247 7700Fax: 44-23-9245 0396

India

304 Sky Station,Plot No. 109,Viman Nagar,Pune 411014,India

Tel: 91-20-4131 4682Fax: 91-20-4131 4683

Russia & CIS

Russia

Lot 11, Novinskiy Boulevard,Moscow,121099 Russian Federation

Tel: 7-499-255 6953Fax: 7-499-255 6953

Malaysia

Lot 5755-6, Kidam ai Industrial Par k,Bukit Angkat,43000 Kajang,Selangor Darul Ehsan,Malaysia

Tel: 603-8924 9000Fax:603-8739 5020

China

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

Tel: 86-535-658 8999Fax: 86-535-658 1999

Middle East & North Africa

United Arab Emirates

Platinum Business CentreOffice No. 704P. O. Box 30922,

Al Nahda 2nd, Dubai, UAE

Tel: 971-4-280 6699Fax: 971-4-280 9886

Asia

Singapore

146B, Paya Lebar Road,No. 05-01,

ACE Bui ld ing,Singapore 409017

Tel: 65-6842 2012Fax: 65-6842 2013

Products that perform By people who care

Americas

United States of America

175 South Street,West Hartford,CT 06110, USA

Tel: 1-860-249 8671Fax: 1-860-953 3300

dunham-bush afhx-6sr-77-191tr

Documents