AIR-COOLED, RECIPROCATING CONDENSING UNITS

Product Manual PM ACR

Group: Chiller

Effective: April 1999

Supersedes: PM ACR/AGR

© 1997 McQuay International

AIR-COOLED, RECIPROCATING CONDENSING UNITS

ACR 060AS – ACR 120AS,

60 to 120 Tons (205 to 410 kW)

60 Hertz, R-22

2 Product Manual ACR

Table of Contents

Introduction .................................3

Features and Benefits ..................4

Design Advantages ......................5CDE Water Chillers......................................8

Selection Procedure, ACR-AS ....9Selection Procedure .....................................9Application Adjustment Factors..................9

Performance Data, ACR-AS......10Part Load Data, ACR-AS .......................... 12

Selection Procedure, CDE ........14

Performance Data, CDE............14

Sound Data, ACR-AS................15

Pressure Drops ..........................18CDE Evaporators ...................................... 18

Electrical Data...........................19Electrical Notes .........................................22Field Wiring Diagram, ACR......................23

Physical Data,............................25ACR-AS .....................................................25CDE Evaporators.......................................27

Dimensional Data, ACR-AS .....28CDE Evaporators.......................................30

Application Data .......................31Clearances ..................................................31Unit Placement...........................................32Sound Isolation..........................................32Typical Chilled Water Piping.....................32Refrigerant Piping......................................33

Optional Features ......................39

ACR-AS Specification..............41

Our facility is ISO9002 Certified

"McQuay" is a registered trademark of McQuay International1997 McQuay International

"Illustrations cover the general appearance of McQuay International products at the time of publication and wereserve the right to make changes in design and construction at anytime without notice"

Product Manual ACR 3

Introduction

IMPORTANT INFORMATION

McQuay International offers air-cooled condensing units from 10- to 120- tons (35 to420 kW) utilizing scroll and reciprocating compressors for use with a variety ofevaporator types. Additionally, most air-cooled chillers up to 425 tons (1500 kW) areavailable with their evaporators shipped loose for remote mounting.

This Product Manual contains information on Model ACR---AS air-cooledcondensing units. Capacity control, liquid line specialties, and evaporator are notincluded with these units.

A C R XXX A S

Information is also included on the Model CDE direct expansion water chillers thatcan be used in conjunction with the Model ACR condensing unit. No controls orrefrigerant specialties are included with the evaporators.

C DE XX XX - X

Air-Cooled

Condensing Unit

Reciprocating Compressor

Design Vintage

Capacity: Nominal Tons

S= Standard Cooling

Cooler Direct Expansion

Tube Count Code

Length (ft)

Diameter (in)


Features and Benefits

Efficiency• Cross-circuit compressor staging

• Copeland Discus compressors

• Exceeds ASHRAE Std 90.1 for efficiency

Reliability• Rugged compressor design

• Factory installed safety controls

• Code and agency approval

Flexibility • Sizes available in 5 ton increments

• Most sizes available from stock

• SpeedTrol (optional)

• Small footprint

Serviceability• Dual refrigerant circuits

• Easy servicing -- Electrical and refrigerantcomponents are readily accessible

• Field installed specific controls


Design Advantages

ConstructionFactory assembled and mounted, to the extent described, on heavy-gauge painted phosphatizedgalvanized steel channel base. This base distributes the unit weight for roof loading. Varied andconvenient installation is possible by virtue of the unit's small footprint.

CompressorsThe ACR product line uses Copeland DISCUS valve semi-hermetic compressors. These ruggedcompressors are designed for R-22 and the high loading associated with air-cooled applications.

Semi-hermetic, 1750 rpm induction type motors are used. The motors are refrigerant-gas cooled.Solid-state modules in the motor terminal box respond to temperature sensors imbedded in all threemotor windings, providing inherent thermal overload protection for all run and start conditions.

The compressor housing is constructed from closed grained, high nickel content, alloy cast-iron withno bolted joint between the motor and compressor. The housing includes a cast-iron cylinder head andstator cover, and a crankcase oil sightglass. A suction strainer built into the compressor in the gasstream between the suction service valve and the motor, filters out foreign and abrasive particles. Aninternal relief valve relieves discharge pressure to the suction side for safety protection at highcompression ratios as required by ANSI/ASHRAE 15 Safety Code.

Main bearings are solid cast bronze insert type with oversized bearing areas that result in ultra-lowbearing loading.

The crankshaft is die-forged, high strength iron alloy with integral counterweights, statically anddynamically balanced for smooth operation.

Connecting rods are lightweight aluminum with integral bearing surfaces on the crankshaft and pistonends. Pistons are close grain cast iron with oil and compression rings. Piston pins are full floatingtype for long life.

Compressors have a forced-feed lubrication system with positive oil displacement, a reversible oilpump, and an operating oil charge. The pump feeds oil through rifle drilled passages in the crankshaftto all bearing surfaces. Magnetic plugs trap magnetic particles that enter the crankcase. The oil supplyfilters through a large area oil strainer. A crankcase heater minimizes oil dilution by refrigerant at start.

Condenser CoilsCondenser coils have internally enhanced seamless copper tubes arranged in a staggered row pattern.The coils are mechanically expanded into McQuay lanced and rippled aluminum fins with full fincollars. An integral subcooler circuit provides subcooling, virtually eliminating the possibility ofliquid flashing. Options such as copper fins and ElectroFin baked epoxy coating are available forextreme duty. Wire mesh coil guards are provided as standard to protect fins from damage.

Condenser Fans and MotorsMultiple direct drive dynamically balanced propeller fans operate in formed venturi openings at low tipspeeds for maximum efficiency and minimum noise and vibration. A heavy-gauge vinyl-coated fanguard protects each fan.

Each condenser fan motor is heavy-duty, 3-phase with permanently lubricated ball bearings andinherent overload protection. Totally enclosed fan motors are available as an option on all sizes, lowambient SpeedTrol Head Pressure Control option includes a single-phase motor with fan speed controlon the lead fan for each circuit.


Electrical Control CenterOperating and safety controls (excluding capacity step control) and motor starting components areseparately housed in a centrally located, weatherproof control panel with hinged and key locked doors.The following components are housed in the panel:

• Power terminal block

• Control, input, and output terminal block

• Control transformer

• Optional disconnect switch with through-the-door handle

• Compressor contactors (circuit breakers are available as an option) Inherent thermal and overloadprotection is standard

• Phase voltage monitor with under/over/phase reversal protection

• Fan contactors with separate fuse blocks

• Optional ground fault protection

• The standard FanTrol system controls fan staging for control of refrigerant discharge pressure.The FanTrol system cycles condenser fans based on discharge pressure and outdoor temperatureand is suited for operation to 40°F (4.4°C).

• The optional SpeedTrol control uses both fan cycling and fan speed control on the lead fan percircuit and allows operation to 0°F (-18°C) outdoor temperature.

• Mechanical high pressure cutout

Control CircuitThe elimination of staging controls furnished with the unit gives the designer the option of choosingany staging controller that will connect to the 4 or 6 stages of capacity reduction available on the ACRunits. These temperature control components are supplied by others and specifically designed for theapplication. The control circuit has a system shut off switch for the unit and a pumpdown switch percircuit. Each compressor circuit has a 5 minute anti-cycle timer to prevent short cycling. Therefrigerant circuits are protected with an evaporator pressure switch with a pre-set switch to stop thatcircuit.

The control circuit contains a 2.75 minute bypass timer per circuit used on start up to give the systemtime to stabilize on low ambient start ups (Low Ambient Start). The control circuit will pumpdowneach circuit after satisfying the cooling load. If the low side pressure increases, the circuit will startpumpdown again after a 120 minute time delay (Limited Pumpdown).


Figure 1, ACR-AS Piping Schematic (one of two circuits shown)


CDE Water ChillersThe CDE evaporator is direct expansion, shell-and-tube type with water flowing in the baffled shellside and refrigerant flowing through the tubes. Two independent refrigerant circuits within theevaporator serve dual refrigerant circuits.

The evaporator has a carbon steel shell and seamless high efficiency copper tubes, roller expanded, intoa carbon steel tube sheet. Water baffles are polypropylene to resist corrosion.

Refrigerant heads are carbon steel with multi-pass baffles to ensure oil return and are removable topermit access to the tubes from either end. For water removal, 3/8" (10mm) vent and drain plugs areprovided on the top and bottom of the shell.

To allow for the installation of the CDE in an area subject to freezing temperatures, the evaporator iswrapped with an electric resistance heater cable and insulated with 3/4" (19mm) thick vinyl nitratepolymer sheet insulation. This will protect against water freeze-up at ambient air temperatures down to-20°F (-29°C). A factory supplied and installed ambient air thermostat controls the heater cable.

The fitted and glued in place insulation has a K factor of 0.28 at 75°F (23°C).

The refrigerant (tube) side maximum working pressure is 225 psig (1552 kPa). The water sideworking pressure is 175 psig (1206 kPa). Each evaporator is designed, constructed, inspected, andstamped according to the requirements of the ASME Boiler and Pressure Vessel Code. Doublethickness insulation is available as an option.


Selection Procedure, ACR-AS

Selection ProcedureACR condensing units are selected in conjunction with some kind of evaporator equipment. The ACRratings are based on saturation suction temperature at the compressor inlet and on ambient airtemperature. For a system selection, the ACR condensing unit is usually selected first, then the lineloss is added to the condensing unit saturated suction temperature to determine the saturatedevaporating temperature. This temperature is used for the selection of the evaporator, whether it be aDX coil or shell and tube heat exchanger. The pipe size can be determined from procedures and data inthe Refrigerant Piping Section. For selection purposes, the tubing size is based on a pressureequivalent of a 2 degree F line loss (equal to about 3 psi pressure drop).

The correction for altitude, Table 1, is applied if applicable, by dividing the required job capacity bythe correction factor to ascertain the unit capacity in the Capacity Tables.

Table 2 and Table 3 (I-P and SI) cover the normal range of saturated suction temperatures and ambientair temperatures.

Selection example, Inch-Pound UnitsGiven:

790 mbh job requirement95°F ambient temperature40°F saturated suction temperature2,000 foot altitude

1. Correct for altitude by dividing the required capacity by the correction factor from Table 1

790 mbh required / 0.986 factor = 801 mbh corrected capacity.

2. From Performance Table 2, an AGR 075 at the given conditions will produce 810.2 mbh with acompressor kW input of 77.0 and a unit EER of 9.6.

3. Correct for altitude:

Capacity = 810.2 x 0.986 = 799mbh

Power = 77.0 x 1009 = 77.7 kW

EER = 9.6 x 0.986/1.009 = 9.4

4. An evaporator would be selected at 42°F saturated evaporating temperature.

Selection example-SI unitsUse the same procedure as I-P but use SI tables and units.

Application Adjustment Factors

Altitude Correction FactorsPerformance tables are based at sea level. Elevations other than sea level affect the performance of theunit. The decreased air density will reduce condenser capacity consequently reducing the unit'sperformance. For performance at elevations other than sea level refer to Table 1.

Table 1, Correction FactorsAltitude Capacity Power

Sea Level 1.000 1.0002000 ft (610 m) 0.986 1.0094000 ft (1220) m 0.973 1.0216000 ft (1830) m 0.959 1.031


Performance Data, ACR-AS

Table 2, Performance Rating, ACR 060AS - 120AS, 60 Hz, I-P UnitsACR Ambient Air TemperatureModel SST 75°F 85°F 95°F 105°F 115°FSize (°F) MBH Comp kW EER MBH Comp kW EER MBH Comp kW EER MBH Comp kW EER MBH Comp

kWEER

35 677.2 46.7 12.8 642.0 50.7 11.3 604.8 55.7 9.8 568.9 58.8 8.8 533.7 63.5 7.7060AS 40 732.7 49.2 13.2 694.8 53.5 11.6 654.0 58.6 10.1 615.3 61.9 9.0 576.6 66.8 7.9

45 787.6 51.6 13.6 746.8 56.0 12.0 703.2 61.4 10.4 661.7 64.8 9.3 620.2 70.0 8.150 842.4 52.7 14.3 798.8 57.2 12.6 752.4 62.7 10.9 708.1 66.2 9.8 663.8 71.5 8.535 710.7 48.8 12.9 673.8 52.9 11.4 634.7 58.1 9.9 597.0 61.3 8.8 560.1 66.3 7.7

065AS 40 769.0 51.4 13.3 729.1 55.9 11.7 686.3 61.2 10.2 645.8 64.6 9.1 605.2 69.6 8.045 826.6 53.9 13.8 783.8 58.5 12.1 738.0 64.1 10.5 694.5 67.6 9.4 650.9 73.0 8.250 884.1 55.0 14.4 838.4 59.7 12.7 789.7 65.4 11.0 743.2 69.0 9.9 696.7 74.5 8.635 784.7 54.5 12.7 743.9 59.2 11.2 700.7 65.0 9.7 659.2 68.6 8.7 618.4 74.2 7.6

070AS 40 849.0 57.5 13.1 805.0 62.4 11.5 757.8 68.4 10.0 713.0 72.3 9.0 668.1 78.0 7.845 912.6 60.2 13.5 865.3 65.4 11.9 814.8 71.7 10.3 766.7 75.7 9.2 718.7 81.7 8.150 976.1 61.5 14.2 925.6 66.7 12.5 871.8 73.2 10.8 820.5 77.3 9.7 769.2 83.4 8.535 839.0 61.4 12.2 795.4 66.6 10.7 749.2 73.1 9.3 704.8 77.2 8.3 661.2 83.4 7.3

075AS 40 907.8 64.7 12.6 860.7 70.3 11.1 810.2 77.0 9.6 762.3 81.2 8.6 714.4 87.5 7.545 975.7 67.8 13.0 925.2 73.6 11.4 871.2 80.6 9.9 819.8 85.0 8.9 768.4 91.7 7.850 1043.7 69.2 13.6 989.7 75.1 12.0 932.2 82.3 10.4 877.3 86.8 9.3 822.4 93.7 8.135 923.3 63.3 12.4 875.4 68.9 11.0 824.6 75.9 9.5 775.7 80.2 8.5 727.7 86.9 7.4

080AS 40 999.1 66.8 12.8 947.3 72.8 11.3 891.7 80.0 9.8 839.0 84.6 8.8 786.2 91.4 7.745 1073.9 70.2 13.2 1018.2 76.4 11.7 958.8 83.9 10.1 902.2 88.7 9.0 845.7 95.9 7.950 1148.6 71.7 13.9 1089.2 78.0 12.2 1025.9 85.7 10.6 965.5 90.6 9.5 905.1 98.0 8.335 1038.9 68.6 13.0 984.9 74.6 11.5 927.8 82.1 10.0 872.7 86.8 8.9 818.8 94.0 7.8

090AS 40 1124.1 72.4 13.5 1065.9 78.9 11.9 1003.3 86.6 10.3 944.0 91.5 9.2 884.6 98.8 8.145 1208.3 76.0 13.9 1145.7 82.7 12.2 1078.8 90.8 10.6 1015.2 95.9 9.5 951.5 103.6 8.350 1292.4 77.6 14.6 1225.5 84.4 12.8 1154.3 92.7 11.1 1086.4 97.9 10.0 1018.4 105.9 8.735 1134.8 76.0 13.0 1075.9 82.5 11.5 1013.4 90.7 10.0 953.3 95.8 8.9 894.4 103.6 7.8

100AS 40 1227.9 80.1 13.5 1164.3 87.2 11.9 1095.9 95.6 10.3 1031.1 100.9 9.2 966.3 108.9 8.145 1319.8 84.0 13.9 1251.5 91.3 12.2 1178.4 100.2 10.6 1108.9 105.8 9.5 1039.3 114.2 8.350 1411.7 85.8 14.6 1338.7 93.2 12.8 1260.9 102.3 11.1 1186.6 108.0 10.0 1112.4 116.7 8.735 1230.7 88.0 12.4 1166.8 95.5 11.0 1099.1 104.8 9.5 1033.9 110.6 8.5 970.0 119.5 7.4

110AS 40 1331.7 92.7 12.8 1262.7 100.7 11.3 1188.5 110.3 9.8 1118.3 116.4 8.8 1048.0 125.5 7.745 1431.4 97.2 13.2 1357.2 105.4 11.7 1278.0 115.5 10.1 1202.6 121.9 9.0 1127.2 131.5 7.950 1531.0 99.2 13.9 1451.8 107.6 12.2 1367.5 117.9 10.6 1286.9 124.4 9.5 1206.4 134.3 8.335 1325.5 98.9 12.1 1256.7 107.2 10.6 1183.7 117.5 9.2 1113.5 123.9 8.3 1044.7 133.8 7.2

120AS 40 1434.2 104.1 12.5 1359.9 113.0 11.0 1280.1 123.7 9.5 1204.4 130.4 8.5 1128.6 140.5 7.445 1541.6 109.1 12.8 1461.7 118.3 11.3 1376.4 129.4 9.8 1295.2 136.5 8.8 1214.0 147.2 7.750 1648.9 111.3 13.5 1563.6 120.6 11.9 1472.7 132.1 10.3 1386.0 139.3 9.2 1299.3 150.3 8.1

Notes:1. To determine total unit power (kW), add the following to the compressor kW shown in table: Models 060AS through 065AS, add 6.2 kW for fans and controls Models 070AS through 075AS, add 7.4 kW for fans and controls Models 080AS through 120AS, add 11.0 kW for fans and controls2. EER = Unit output Btu/hr ÷ unit input watts.3. SST = Saturated Suction Temperature


Table 3, Performance Ratings, ACR 060AS - 120AS, 60 Hz, SI UnitsACR Ambient Air TemperatureModel SST 75°F 85°F 95°F 105°F 115°FSize (°F) kW Comp kW COP kW Comp kW COP kW Comp kW COP kW Comp kW COP kW Comp kW COP

35 198.5 46.7 3.7 188.2 50.7 3.3 177.2 55.7 2.8 166.7 58.8 2.5 156.4 63.5 2.2060AS 40 214.8 49.2 3.8 203.6 53.5 3.4 191.7 58.6 2.9 180.3 61.9 2.6 169.0 66.8 2.3

45 230.8 51.6 3.9 218.9 56.0 3.5 206.1 61.4 3.0 193.9 64.8 2.7 181.8 70.0 2.350 246.9 52.7 4.1 234.1 57.2 3.6 220.5 62.7 3.2 207.5 66.2 2.8 194.6 71.5 2.535 208.3 48.8 3.8 197.5 52.9 3.4 186.0 58.1 2.9 175.0 61.3 2.6 164.2 66.3 2.3

065AS 40 225.4 51.4 3.9 213.7 55.9 3.5 201.2 61.2 3.0 189.3 64.6 2.7 177.4 69.6 2.445 242.3 53.9 4.1 229.7 58.5 3.6 216.3 64.1 3.1 203.5 67.6 2.8 190.8 73.0 2.450 259.1 55.0 4.3 245.7 59.7 3.8 231.4 65.4 3.3 217.8 69.0 2.9 204.2 74.5 2.535 230.0 54.5 3.7 218.0 59.2 3.3 205.4 65.0 2.8 193.2 68.6 2.5 181.3 74.2 2.2

070AS 40 248.8 57.5 3.8 235.9 62.4 3.4 222.1 68.4 2.9 209.0 72.3 2.6 195.8 78.0 2.345 267.5 60.2 3.9 253.6 65.4 3.5 238.8 71.7 3.0 224.7 75.7 2.7 210.6 81.7 2.350 286.1 61.5 4.1 271.3 66.7 3.6 255.5 73.2 3.2 240.5 77.3 2.8 225.4 83.4 2.535 245.9 61.4 3.6 233.1 66.6 3.1 219.6 73.1 2.7 206.6 77.2 2.4 193.8 83.4 2.1

075AS 40 266.1 64.7 3.7 252.3 70.3 3.2 237.5 77.0 2.8 223.4 81.2 2.5 209.4 87.5 2.245 286.0 67.8 3.8 271.2 73.6 3.3 255.3 80.6 2.9 240.3 85.0 2.6 225.2 91.7 2.350 305.9 69.2 4.0 290.1 75.1 3.5 273.2 82.3 3.0 257.1 86.8 2.7 241.0 93.7 2.435 270.6 63.3 3.7 256.6 68.9 3.3 241.7 75.9 2.8 227.3 80.2 2.5 213.3 86.9 2.2

080AS 40 292.8 66.8 3.8 277.6 72.8 3.4 261.3 80.0 2.9 245.9 84.6 2.6 230.4 91.4 2.345 314.7 70.2 3.9 298.4 76.4 3.5 281.0 83.9 3.0 264.4 88.7 2.7 247.8 95.9 2.350 336.6 71.7 4.1 319.2 78.0 3.6 300.7 85.7 3.2 283.0 90.6 2.8 265.3 98.0 2.535 304.5 68.6 3.8 288.7 74.6 3.4 271.9 82.1 2.9 255.8 86.8 2.6 240.0 94.0 2.3

090AS 40 329.5 72.4 3.9 312.4 78.9 3.5 294.0 86.6 3.0 276.7 91.5 2.7 259.3 98.8 2.445 354.1 76.0 4.1 335.8 82.7 3.6 316.2 90.8 3.1 297.5 95.9 2.8 278.9 103.6 2.450 378.8 77.6 4.3 359.2 84.4 3.8 338.3 92.7 3.3 318.4 97.9 2.9 298.5 105.9 2.535 332.6 76.0 3.8 315.3 82.5 3.4 297.0 90.7 2.9 279.4 95.8 2.6 262.1 103.6 2.3

100AS 40 359.9 80.1 3.9 341.2 87.2 3.5 321.2 95.6 3.0 302.2 100.9 2.7 283.2 108.9 2.445 386.8 84.0 4.1 366.8 91.3 3.6 345.4 100.2 3.1 325.0 105.8 2.8 304.6 114.2 2.450 413.8 85.8 4.3 392.3 93.2 3.8 369.5 102.3 3.3 347.8 108.0 2.9 326.0 116.7 2.535 360.7 88.0 3.7 342.0 95.5 3.3 322.1 104.8 2.8 303.0 110.6 2.5 284.3 119.5 2.2

110AS 40 390.3 92.7 3.8 370.1 100.7 3.4 348.3 110.3 2.9 327.7 116.4 2.6 307.1 125.5 2.345 419.5 97.2 3.9 397.8 105.4 3.5 374.6 115.5 3.0 352.5 121.9 2.7 330.4 131.5 2.350 448.7 99.2 4.1 425.5 107.6 3.6 400.8 117.9 3.2 377.2 124.4 2.8 353.6 134.3 2.535 388.5 98.9 3.6 368.3 107.2 3.1 346.9 117.5 2.7 326.4 123.9 2.4 306.2 133.8 2.1

120AS 40 420.3 104.1 3.7 398.6 113.0 3.2 375.2 123.7 2.8 353.0 130.4 2.5 330.8 140.5 2.245 451.8 109.1 3.8 428.4 118.3 3.3 403.4 129.4 2.9 379.6 136.5 2.6 355.8 147.2 2.350 483.3 111.3 4.0 458.3 120.6 3.5 431.6 132.1 3.0 406.2 139.3 2.7 380.8 150.3 2.4

Notes:1. To determine total unit kW, add the following to the compressor kW shown in table: Models 060AS through 065AS, add 6.2 kW for fans and controls Models 070AS through 075AS, add 7.4 kW for fans and controls Models 080AS through 120AS, add 11.0 kW for fans and controls2. COP = Output Btu/hr ÷ input kW x 3,413 Btu/kWh watts.3. SST = Saturated Suction Temperature


Part Load Data, ACR-ASTable 4, ACR-AS Part Load Data

ACR 060As Tons Btuh Unit kW EER100% 58.6 703.2 67.6 10.475% 43.9 526.7 36.2 14.554% 31.7 380.4 26.4 14.450% 29.3 351.6 24.3 14.531% 17.9 214.5 15.0 14.325% 14.7 175.8 12.4 14.2

ACR 065AS Tons Btuh Unit kW EER100% 61.5 738.0 70.5 10.585% 52.3 628.0 42.5 14.875% 46.1 553.5 38.2 14.565% 40.2 481.9 32.7 14.750% 30.8 369.0 25.1 14.746% 28.0 336.5 22.9 14.725% 15.4 184.5 12.7 14.623% 14.0 168.3 11.5 14.6




Notes:1. Rated in Accordance with ARI Standard 365-94 for condensing units.2. Bold ratings are actual unload points; 75%, 50%, 25%. Part load data is Interpolated between actual staging points.3. Full load point at 45°F saturated suction temperature and 95°F ambient air temperature.4. Part load points based on 50°F saturated suction temperature and 80°F ambient air

temperature per ARI Standard 365-94,

(Tables continued on next page)






Notes:1. Rated in Accordance with ARI Standard 365-94 for Condensing Units.2. Bold ratings are actual unload points, 75%, 50%, 25% part load data is Interpolated between actual staging points.3. Full load points at 45°F saturated suction temperature and 95°F ambient air temperature4. Part load points based at 50°F saturated suction temperature and 80°F ambient

air temperature per ARI Standard 365-94,


Selection Procedure, CDE

CDE evaporator capacity is based on refrigerant saturated evaporating temperature and leaving chilledfluid temperature. Table 5 through Table 8 contain data for normal operating ranges. Consult yourlocal McQuay sales representative for conditions outside the table.

Performance Data, CDE

Table 5, Performance Data, 42°°F WaterCapacity at 42°F Leaving Water Temperature (MBH)

CDE MODEL Saturated Evaporating Temperature32°F 33°F 34°F 35°F 36°F 37°F

CDE 1204-2 1693 1470 1283 1116 972 834CDE 1204-1 1666 1452 1271 1110 962 768CDE 1255-1 1993 1783 1596 1428 1224 1008CDE 1455-1 2327 2107 1908 1728 1500 1260



CDE 1204-2 1693 1470 1283 1116 972 834CDE 1204-1 1666 1452 1271 1110 962 768CDE 1255-1 1993 1783 1596 1428 1224 1008CDE 1455-1 2327 2107 1908 1728 1500 1260



CDE 1204-2 1693 1470 1283 1116 972 834CDE 1204-1 1666 1452 1271 1110 962 768CDE 1255-1 1993 1783 1596 1428 1224 1008CDE 1455-1 2327 2107 1908 1728 1500 1260



CDE 1204-2 1693 1470 1283 1116 972 834CDE 1204-1 1666 1452 1271 1110 962 768CDE 1255-1 1993 1783 1596 1428 1224 1008CDE 1455-1 2327 2107 1908 1728 1500 1260


Sound Data, ACR-AS

Table 9, ACR-AS, Sound Pressure Octave Band DataACR-AS Octave Band and Center Frequency, Hz Overall

Unit Model 63 125 250 500 1000 2000 4000 8000 A-Weighted060AS 65 65 64 63 61 55 53 51 65065AS 65 65 64 63 61 55 53 51 65070AS 65 65 64 63 61 55 53 52 65075AS 65 65 64 64 62 56 53 53 66080AS 66 67 65 65 62 56 55 55 67090AS 66 68 65 65 62 56 56 55 67100AS 67 69 66 65 62 56 56 55 67110AS 68 69 67 66 63 58 58 56 68120AS 69 70 68 66 63 58 58 56 68

Note: 60 hertz data at 30 feet distance from the sides of the unit.

Table 10, ACR-AS, Sound Power Octave Band DataACR-AS Octave Band and Center Frequency, Hz Overall

Unit Model 63 125 250 500 1000 2000 4000 8000 A-Weighted060AS 92 92 91 90 88 82 80 78 92065AS 92 92 91 90 88 82 80 78 92070AS 92 92 91 90 88 82 80 79 92075AS 92 92 91 91 89 83 81 80 93080AS 93 94 92 92 89 83 82 82 94090AS 93 95 92 92 89 83 83 82 94100AS 94 96 93 92 89 83 83 82 94110AS 95 96 94 93 90 85 86 83 95120AS 96 97 95 93 90 85 86 83 95

Note: Sound power octave band data, dB, per ARI Standard 370.

Sound levels are as important as unit cost and efficiency, and must be addressed before to the start ofany development program. Efforts by McQuay design engineers to design chillers that are sensitive tothe sound requirements of the market have paid off.

Background InformationSound is a vibration in an elastic medium and is essentially a pressure and particle displacementphenomena. A vibrating body produces compression waves and as the waves are emitted from thevibrating body, molecules are ultimately compressed. These values are transmitted through gas, liquid,solid-anything which is elastic or viscous.

The sound data provided in this section is presented with both sound pressure and sound power levels.Sound power is the total sound energy radiated by a source per unit of time integrated over the surfacethrough which the sound is radiated. Sound power is a calculated quantity and cannot be measureddirectly like sound pressure. Sound power is not dependent on the surrounding environment ordistance from the source, as is sound pressure.

Sound pressure varies with the distance from the source and is dependent on its surroundings. Forexample, a brick wall located 10 feet from a unit will affect the sound pressure measurementsdifferently than a brick wall at 20 feet. Sound pressure is measured in decibels (dB), which is adimensionless ratio (on a logarithmic scale) between measured sound pressure and a reference soundpressure level.

Sound Pressure Levels - Full LoadAll sound pressure tables give the overall "A" weighted sound pressure levels which are consideredtypical of what may be measured in a free field with a hand held sound meter, in the absence of anynearby reflective surfaces. The sound pressure levels are measured at 30 feet (10 meters) from the sideof the unit at 100% unit load and ARI conditions. 95°F (35°C) ambient air temperature and 54/44°F(12/7°C) evaporator water temperatures for air-cooled units.


Sound Power LevelsAcoustical consultants may require sound power octave band data to perform a detailed acousticalanalysis. The tables present sound power levels per ARI Standard 370, “Sound Rating of LargeOutdoor Refrigerating and Air Conditioning Equipment”. These standards were developed to establishuniform methods of determining the sound power radiated by large outdoor and indoor equipment.The aforementioned methods are based on providing sound power levels by octave band and theoverall ‘A’ weighted value. Measurements are taken over a prescribed area around the unit and the datais mathematically calculated to give the sound power, dB.

Sound Reduction due to Distance from the UnitThe distance between a source of sound and the location of the sound measurement, plays an importantrole in minimizing sound problems. The equation below can be used to calculate the sound pressurelevel at any distance if the sound power is known.

Lp=Lw-(20 log r) + (10 log Q) - .5

Lp = sound pressure

Lw = sound power

r = distance from unit in feet

Q = directionality factor

The directionality factor is a dimensionless number that compensates for the type of sound radiationfrom the source. Figure 2 shows the typical Q values of different reflecting surfaces.

For a unit sitting on a flat roof with no other reflective surfaces or attenuation due to grass, snow, etc.,between source and receiver: Q=2.

With Q=2, the equation simplifies to:

Lp = Lw - (20)(log r) + 2.5

Figure 2, "Q" Values

Uniform Spherical Radiation Uniform Hemispherical Radiation Uniform Radiation over 1/4 of sphere

Q=1 no reflecting surface Q=2 single reflecting surface Q=4 two reflecting surfaces


Unit Orientation to Minimize SoundThe unit’s sound is directional in nature allowing the contractor/engineer to position the unit tominimize potential noise problems. Because the sound pressure levels are lower at both ends of theunit than at the sides, the unit should be oriented such that the control box end or end opposite thecontrol box faces the direction where the lowest sound level is required.

The control box end provides an excellent acoustic barrier to the compressor sound as it covers onefull end of the unit. The sound pressure levels at the control box end will be 4 dBA less than on thesides.

Figure 3, Sound Directionality

Sound Pressure Levels - Low Ambient OperationUnit operation at a lower ambient temperature than 95°F will also result in lower sound pressurelevels. The sound pressure level will decrease approximately 1 dBA for ambient air temperaturesbetween 85°F and 94°F, approximately 2 dBA for ambient air temperatures between 75°F and 84°F,and approximately 3 dBA for ambient air temperatures between 65°F and 74°F.


Pressure Drops

CDE EvaporatorsFigure 4, Pressure Drops

NOMINAL MAXIMUM MINIMUMCDE PD Flow PD Flow PD FlowSize (ft) of Water (gpm) (lps) (ft) of Water (gpm) (lps) (ft) of Water (gpm) (lps)

1204-2 15.8 130 8.20 39.7 217 13.67 6.8 81 5.131204-1 10.0 152 9.59 25.1 253 15.98 4.3 95 5.991255-1 8.9 172 10.85 22.5 287 18.09 3.8 108 6.781455-1 10.5 208 13.12 26.3 347 21.87 4.5 130 8.20


Electrical Data

Table 11, 60 Hz, Single Point Power Electrical DataMinimum POWER SUPPLY Max. Fuse

ACR-A Circuit Field Wire Conduit Hub orUnit Volts Ampacity Wire Nominal HACR Breaker

Model (MCA) Quantity Gauge Quantity Size Size208 231 3 250 1 2.00 300230 231 3 250 1 2.00 300

060A 380 134 3 1/0 1 1.5 175460 114 3 #2 1 1.25 150575 90 3 #3 1 1.00 125208 237 3 250 1 2.00 300230 237 3 250 1 2.00 300

065A 380 137 3 1/0 1 1.50 175460 117 3 #1 1 1.00 150575 90 3 #3 1 1.00 125208 271 3 300 1 2.50 350230 258 3 300 1 2.50 350

070A 380 150 3 1/0 1 1.50 200460 133 3 1/0 1 1.50 175575 98 3 #3 1 1.00 125208 298 3 350 1 2.50 400230 275 3 300 1 2.50 350

075A 380 160 3 2/0 1 1.50 225460 146 3 1/0 1 1.50 200575 104 3 #2 1 1.25 125208 351 3 500 1 3.00 450230 329 3 400 1 2.50 450

080A 380 220 3 4/0 1 2.00 300460 163 3 2/0 1 1.50 225575 126 3 #1 1 1.50 150208 384 6 3/0 2 2.00 500230 373 3 500 1 3.00 500

090A 380 240 3 250 1 2.50 300460 187 3 3/0 1 2.00 250575 151 3 2/0 1 1.50 200208 411 6 4/0 2 2.00 500230 408 6 4/0 2 2.00 500

100A 380 256 3 300 1 2.50 350460 206 3 4/0 1 2.00 250575 171 3 3/0 1 2.00 225208 461 6 250 2 2.00 600230 458 6 4/0 2 2.00 600

110A 380 269 3 300 1 2.50 350460 220 3 4/0 1 2.00 300575 176 3 3/0 1 2.00 225208 501 6 250 2 2.00 700230 498 6 250 2 2.00 700

120A 380 279 3 300 1 2.50 350460 231 3 250 1 2.00 300575 180 3 3/0 1 2.00 250

All Electrical Data notes are on page 34


Table 12, 60 Hz, Compressor & Condenser Fan Motor Amp Draw Rated Load Amps Locked Rotor Amps

ACR-A Compressors Fan No. Of Fan CompressorsUnit Volts No. No. Motors Fan Motors Across-The-Line Reduced InrushSize 1 2 (Each) Motors (Each) No. 1 No. 2 No. 1 No. 2

208 89 95 5.8 4 23.7 470 565 292 340230 89 95 5.8 4 21.4 470 565 292 340

060A 380 52 55 3.4 4 14.4 285 342 N/A N/A460 44 47 2.8 4 10.7 235 260 141 156575 36 36 2.3 4 11.5 200 230 130 138208 95 95 5.8 4 23.7 565 565 340 340230 95 95 5.8 4 21.4 565 565 340 340

065A 380 55 55 3.4 4 14.4 342 342 N/A N/A460 47 47 2.8 4 10.7 260 260 156 156575 36 36 2.3 4 11.5 230 230 138 138208 95 122 5.8 4 23.7 565 650 340 400230 95 112 5.8 4 21.4 565 594 340 340

070A 380 55 65 3.4 4 14.4 342 365 N/A N/A460 47 60 2.8 4 10.7 260 315 156 195575 36 42 2.3 4 11.5 230 245 138 152208 122 122 5.8 4 23.7 650 650 400 400230 112 112 5.8 4 21.4 594 594 340 340

075A 380 65 65 3.4 4 14.4 365 365 N/A N/A460 60 60 2.8 4 10.7 315 315 195 195575 42 42 2.3 4 11.5 245 245 152 152208 135 135 7.8 6 30.5 754 754 463 463230 127 127 7.2 6 27.6 594 594 340 340

080A 380 87 87 4.1 6 20.0 365 365 N/A N/A460 63 63 3.6 6 13.8 315 315 195 195575 48 48 3.0 6 11.0 245 245 152 152208 135 162 7.8 6 30.5 754 1070 463 654230 127 162 7.2 6 27.6 594 1070 340 654

090A 380 87 103 4.1 6 20.0 365 740 N/A N/A460 63 82 3.6 6 13.8 315 510 195 330575 48 68 3.0 6 11.0 245 405 152 262208 162 162 7.8 6 30.5 1070 1070 654 654230 162 162 7.2 6 27.6 1070 1070 654 654

100A 380 103 103 4.1 6 20.0 740 740 N/A N/A460 82 82 3.6 6 13.8 510 510 330 330575 68 68 3.0 6 11.0 405 405 262 262208 162 202 7.8 6 30.5 1070 1070 654 654230 162 202 7.2 6 27.6 1070 1070 654 654

110A 380 103 113 4.1 6 20.0 740 740 N/A N/A460 82 93 3.6 6 13.8 510 510 330 330575 68 72 3.0 6 11.0 405 405 262 262208 202 202 7.8 6 30.5 1070 1070 654 654230 202 202 7.2 6 27.6 1070 1070 654 654

120A 380 113 113 4.1 6 20.0 740 740 N/A N/A460 93 93 3.6 6 13.8 510 510 330 330575 72 72 3.0 6 11.0 405 405 262 262



Table 13, 60 Hz Single Point Power, Field Wiring DataWiring to Standard Wiring to Optional

ACR-A Power Block Non-Fused Disconnect SwitchUnit Volts Terminal Connector Wire Range Terminal Connector Wire RangeSize Amps (Copper Wire Only) Amps (Copper Wire Only)

208 335 # 4 - 400 MCM 250 250-500 MCM230 335 # 4 - 400 MCM 250 250-500 MCM

060A 380 335 # 4 - 400 MCM 150 #2 - 3/0460 335 # 4 - 400 MCM 150 #2 - 3/0575 335 # 4 - 400 MCM 100 #6 - 1/0208 335 # 4 - 400 MCM 250 250-500 MCM230 335 # 4 - 400 MCM 250 250-500 MCM

065A 380 335 # 4 - 400 MCM 150 #2 - 3/0460 335 # 4 - 400 MCM 150 #2 - 3/0575 335 # 4 - 400 MCM 100 #6 - 1/0208 335 # 4 - 400 MCM 400 250 - 500 MCM230 335 # 4 - 400 MCM 400 250 - 500 MCM

070A 380 335 # 4 - 400 MCM 250 #4 - 350 MCM460 335 # 4 - 400 MCM 150 #2 - 3/0575 335 # 4 - 400 MCM 150 #2 - 3/0208 335 # 4 - 400 MCM 400 250 - 500 MCM230 335 # 4 - 400 MCM 400 250 - 500 MCM

075A 380 335 # 4 - 400 MCM 250 #4 - 350 MCM460 335 # 4 - 400 MCM 250 #4 - 350 MCM575 335 # 4 - 400 MCM 150 #2 - 3/0208 840 (2 qty.) 1/0 - 600 MCM 400 250 - 500 MCM230 840 (2 qty.) 1/0 - 600 MCM 400 250 - 500 MCM

080A 380 335 # 4 - 400 MCM 250 #4 - 350 MCM460 335 # 4 - 400 MCM 250 #4 - 350 MCM575 335 # 4 - 400 MCM 150 #2 - 3/0208 840 (2 qty.) 1/0 - 600 MCM 400 250 - 500 MCM230 840 (2 qty.) 1/0 - 600 MCM 400 250 - 500 MCM

090A 380 335 # 4 - 400 MCM 250 #4 - 350 MCM460 335 # 4 - 400 MCM 250 #4 - 350 MCM575 335 # 4 - 400 MCM 250 #4 - 350 MCM208 840 (2 qty.) 1/0 - 600 MCM N/A N/A230 840 (2 qty.) 1/0 - 600 MCM N/A N/A

100A 380 335 # 4 - 400 MCM 400 250 - 500 MCM460 335 # 4 - 400 MCM 250 #4 - 350 MCM575 335 # 4 - 400 MCM 250 #4 - 350 MCM208 840 (2 qty.) 1/0 - 600 MCM N/A N/A230 840 (2 qty.) 1/0 - 600 MCM N/A N/A

110A 380 335 # 4 - 400 MCM 400 250 - 500 MCM460 335 # 4 - 400 MCM 250 #4 - 350 MCM575 335 # 4 - 400 MCM 250 #4 - 350 MCM208 840 (2 qty.) 1/0 - 600 MCM N/A N/A230 840 (2 qty.) 1/0 - 600 MCM N/A N/A

120A 380 335 # 4 - 400 MCM 400 250 - 500 MCM460 335 # 4 - 400 MCM 250 #4 - 350 MCM575 335 # 4 - 400 MCM 250 #4 - 350 MCM



Electrical Notes

Notes for “Electrical Data Single Point” Power:1. Unit wire size ampacity (MCA) is equal to 125% of the largest compressor-motor RLA plus

100% of RLA of all other loads in the circuit including the control transformer.

2. If the control transformer option is furnished, no separate 115V power is required.

3. If a separate 115V power supply is used for the control circuit, then the wire sizing amps is 10amps for all unit sizes.

4. Recommended power lead wire sizes for 3 conductors per conduit are based on 100% conductorampacity in accordance with NEC. Voltage drop has not been included. Therefore, it isrecommended that power leads be kept short. All terminal block connections must be made withcopper (type THW) wire.

5. “Recommended Fuse Sizes” are selected at approximately 150% to 175% of the largestcompressor RLA, plus 100% of all other loads in the circuit.

6. “Maximum Fuse or HACR breaker size” is selected at approximately 225% of the largestcompressor RLA, plus 100% of all other loads in the circuit.

7. The recommended power lead wire sizes are based on an ambient temperature of 86°F (30°C).Ampacity correction factors must be applied for other ambient temperatures. Refer to theNational Electrical Code Handbook.

8. Must be electrically grounded according to national and local electrical codes.

9. MCA may vary slightly due to fan motor options such as SpeedTrol, TEFC.

Voltage Limitations:Within ± 10 percent of nameplate rating.

Notes for “Compressor and Condenser Fan Amp Draw”:1. Compressor RLA values are for wiring sizing purposes only but do not reflect normal operating

current draw at rated capacity. If unit is equipped with SpeedTrol condenser fan motors, the firstmotor on each refrigerant circuit is a single phase, 1hp motor, with a FLA of 2.8 amps at 460volts, 5.6 amps at 208, 230, and 575 volts.

2. Compressor LRA for reduced inrush start are for the first winding only. If the unit is equippedwith SpeedTrol motors, the first motor is a single phase, 1 hp motor, with a LRA of 7.3 amps at460 volts, 14.5 amps at 208, 230, and 575 volts.

Notes for “Field Wiring Data”1. Requires a single disconnect to supply electrical power to the unit. This power supply must either

be fused or use an HACR type circuit breaker.

2. All field wiring to unit power block or optional non-fused disconnect switch must be copper.

3. All field wire size values given in table apply to 75°C rated wire per NEC.


Field Wiring Diagram, ACRFigure 5, ACR-AS, Field Wiring Diagram


Figure 6, ACR-AS, Field Wiring Diagram, Capacity Control Staging


Physical Data,

ACR-ASTable 14, ACR 060AS - 070AS

PHYSICAL DATA ACR-AS MODEL NUMBERSTANDARD EFFICIENCY 060AS 065AS 070AS

BASIC DATA Ckt.1 Ckt.2 Ckt.1 Ckt.2 Ckt.1 Ckt.2Unit Capacity @ ARI Conditions (1), mbh (kW) 703 (205.9) 738 (216.1) 762 (238.5)Number Of Refrigerant Circuits 2 2 2Unit Operating Charge, R-22, Lbs. 46 46 46 46 55 55Unit Operating Charge, R-22, (kg) (20.9) (20.9) (20.9) (20.9) (24.9) (24.9)Cabinet Dimensions, LxWxH, In. 94.0 x 88.2 x 86.2 94.0 x 88.2 x 86.2 94.0 x 88.2 x 96.2Cabinet Dimensions, LxWxH, (mm) 2388 x 2241 x 2190 2388 x 2241 x 2190 2388 x 2241 x 2444Unit Operating Weight, Lbs. (kg) 3642 (1652) 3712 (1684) 3745 (1699)Unit Shipping Weight, Lbs. (kg) 3550 (1610) 3620 (1642) 3635 (1649)Add'l Weight If Copper Finned Coils, Lbs. (kg) 665 (300) 665 (300) 830 (375)COMPRESSORSType Semi-Hermetic Semi-Hermetic Semi-HermeticNominal Horsepower 30 30 30 30 30 35Number Of Cylinders Per Compressor 4 6 6 6 6 6Oil Charge Per Compressor, oz. 140 140 140 140 140 140Oil Charge Per Compressor, (g) (3969) (3969) (3969) (3969) (3969) (3969)CAPACITY REDUCTION STEPS - PERCENT OF COMPRESSOR DISPLACEMENTStandard Staging - Circuit #1 in Lead 0-23-41-64-82-100 0-17-33-50-67 0-15-33-49-67Standard 6 Stages (2) -83-100 -82-100Standard Staging - Circuit #2 in Lead 0-18-41-59-82-100 0-17-33-50-67 0-18-33-51-67Standard 6 Stages (2) -83-100CONDENSERS - HIGH EFFICIENCY FIN AND TUBE TYPE WITH INTEGRAL SUBCOOLINGCoil Face Area,Sq. Ft. 46.4 46.4 46.4 46.4 58 58Coil Face Area, (m2) (4.3) (4.3) (4.3) (4.3) (5.4) (5.4)Finned Height x Finned Length, In. 80 x 83.5 80 x 83.5 80 x 83.5 80 x 83.5 100x 83.5 100x 83.5Finned Height x Finned Length, (mm) 2032 x 2121 2032 x 2121 2032 x 2121 2032 x 2121 2032 x 2121 2032 x 2121Fins Per Inch x Rows Deep 16 x 3 16 x 3 16 x 3 16 x 3 16 x 3 16 x 3Pumpdown Capacity @ 90% Full (lbs) 86 86 86 86 108 108Pumpdown Capacity @ 90% Full (kgs) (39.) (39.) (39.) (39.) (49.) (49.)Maximum Relief Valve Pressure Setting, psig (kPa) 450 (3103) 450 (3103) 450 (3103) 450 (3103) 450 (3103) 450 (3103)CONDENSER FANS - DIRECT DRIVE PROPELLER TYPENumber Of Fans - Fan Diameter, In. (mm) 4 - 28 (712) 4 - 28 (712) 4 - 28 (712)Number Of Motors - HP (kW) 4 - 1.5 (1.1) 4 - 1.5 (1.1) 4 - 2.0 (1.5)Fan And Motor RPM, 60Hz 1140 1140 114060 Hz Fan Tip Speed, FPM (M/Sec) 8357 (35.4) 8357 (35.4) 8357 (35.4)60 Hz Total Unit Airflow, CFM (M3/sec) 36800 (17.4) 36800 (17.4) 40800 (19.3)

NOTES:1. Nominal capacity based on 95°F ambient air and 45°F saturated suction temperature, no refrigerant line loss.2. Does not include evaporator, suction or liquid line charge. Unit shipped with R-22 holding charge.3. Units with 1.0 Hp Fan Motors, Uses 1.5 Hp Fan Motors when unit is 380V / 60 Hz and 575V / 60Hz.


Table 15, ACR 075AS - 090ASPHYSICAL DATA ACR-ASMODEL NUMBER

STANDARD EFFICIENCY 075AS 080AS 090ASBASIC DATA Ckt.1 Ckt.2 Ckt.1 Ckt.2 Ckt.1 Ckt.2Unit Capacity @ ARI Conditions (1), mbh (kW) 871 (255.0) 959 (280.7) 1078 (315.8)Number Of Refrigerant Circuits 2 2 2Unit Operating Charge, R-22, Lbs. 55 55 80 80 80 80Unit Operating Charge, R-22, (kg) (24.9) (24.9) (36.3) (36.3) (36.3) (36.3)Cabinet Dimensions, LxWxH, In. 94.0 x 88.2 x 96.2 136.4 x 88.2 x 96.2 136.4 x 88.2 x 96.2Cabinet Dimensions, LxWxH, (mm) 2388 x 2241 x 2444 3463 x 2241 x 2444 3463 x 2241 x 2444Unit Operating Weight, Lbs. (kg) 3935 (1785) 4670 (2118) 4905 (2225)Unit Shipping Weight, Lbs. (kg) 3825 (1735) 4510 (2046) 4745 (2152)Add'l Weight If Copper Finned Coils, Lbs. (kg) 830 (375) 1245 (565) 1245 (565)COMPRESSORSType Semi-Hermetic Semi-Hermetic Semi-HermeticNominal Horsepower 35 35 40 40 40 50Number Of Cylinders Per Compressor 6 6 6 6 6 8Oil Charge Per Compressor, oz. 140 140 255 255 255 255Oil Charge Per Compressor, (g) (3969) (3969) (7229) (7229) (7229) (7229)CAPACITY REDUCTION STEPS - PERCENT OF COMPRESSOR DISPLACEMENTStandard Staging - Circuit #1 in Lead 0-16-33-49-67 0-17-33-50-67 0-15-42-58-73Standard 6 Stages -83-100 -83-100 -86-100Standard Staging - Circuit #2 in Lead 0-17-33-51-67 0-17-33-50-67 0-27-42-56-71Standard 6 Stages -84-100 -83-100 -85-100CONDENSERS - HIGH EFFICIENCY FIN AND TUBE TYPE WITH INTEGRAL SUBCOOLINGCoil Face Area,Sq. Ft. 58 58 87 87 87 87Coil Face Area, (m2) (5.4) (5.4) (8.1) (8.1) (8.1) (8.1)Finned Height x Finned Length, In. 100x 83.5 100x 83.5 100x125.9 100x125.9 100x125.9 100x125.9Finned Height x Finned Length, (mm) 2032 x 2121 2032 x 2121 2540 x 3183 2540 x 3183 2540 x 3183 2540 x 3183Fins Per Inch x Rows Deep 16 x 3 16 x 3 16 x 3 16 x 3 16 x 3 16 x 3Pumpdown Capacity @ 90% Full (lbs) 108 108 162 162 162 162Pumpdown Capacity @ 90% Full (kgs) (49.) (49.) (73.5) (73.5) (73.5) (73.5)Maximum Relief Valve Pressure Setting, psig (kPa) 450 (3103) 450 (3103) 450 (3103) 450 (3103) 450 (3103) 450 (3103)CONDENSER FANS - DIRECT DRIVE PROPELLER TYPENumber Of Fans - Fan Diameter, In. (mm) 4 - 28 (712) 6 - 28 (712) 6 - 28 (712)Number Of Motors - HP (kW) 4 - 2.0 (1.5) 6 - 2.0 (1.5) 6 - 2.0 (1.5)Fan And Motor RPM, 60Hz 1140 1140 114060 Hz Fan Tip Speed, FPM (M/Sec) 8357 (35.4) 8357 (35.4) 8357 (35.4)60 Hz Total Unit Airflow, CFM (M3/sec) 40800 (19.3) 61200 (28.9) 61200 (28.9)NOTES:

1. Nominal capacity based on 95°F ambient air and 45°F saturated suction temperature, no refrigerant line loss.2. Does not include evaporator, suction or liquid line charge. Unit shipped with R-22 holding charge.3. Units with 1.0 Hp Fan Motors, Uses 1.5 Hp Fan Motors when unit is 380V / 60 Hz and 575V / 60Hz.


Table 16, ACR-100AS - 120ASPHYSICAL DATA ACR-AS MODEL NUMBER

STANDARD EFFICIENCY 100AS 110AS 120ASBASIC DATA Ckt.1 Ckt.2 Ckt.1 Ckt.2 Ckt.1 Ckt.2Unit Capacity @ ARI Conditions (1), mbh (kW) 1178 (344.9) 1278 (374.1) 1376 (402.9)Number Of Refrigerant Circuits 2 2 2Unit Operating Charge, R-22, Lbs. 82 82 82 82 84 84Unit Operating Charge, R-22, (kg) (37.2) (37.2) (37.2) (37.2) (38.1) (38.1)Cabinet Dimensions, LxWxH, In. 136.4 x 88.2 x 96.2 136.4 x 88.2 x 96.2 136.4 x 88.2 x 96.2Cabinet Dimensions, LxWxH, (mm) 3463 x 2241 x 2444 3463 x 2241 x 2444 3463 x 2241 x 2444Unit Operating Weight, Lbs. (kg) 5224 (2370) 5234 (2374) 5056 (2293)Unit Shipping Weight, Lbs. (kg) 5060 (2295) 5070 (2300) 4888 (2217)Add'l Weight If Copper Finned Coils, Lbs. (kg) 1245 (565) 1245 (565) 1245 (565)COMPRESSORSType Semi-Hermetic Semi-Hermetic Semi-HermeticNominal Horsepower 50 50 50 60 60 60Number Of Cylinders Per Compressor 8 8 8 8 8 8Oil Charge Per Compressor, oz. 255 255 255 255 255 255Oil Charge Per Compressor, (g) (7229) (7229) (7229) (7229) (7229) (7229)CAPACITY REDUCTION STEPS - PERCENT OF COMPRESSOR DISPLACEMENTStandard Staging - Circuit #1 in Lead 0-25-50-63-75 0-23-50-61-75 0-25-50-63-75Standard 6 Stages -88-100 -86-100 -88-100Standard Staging - Circuit #2 in Lead 0-25-50-63-75 0-27-50-64-75 0-25-50-63-75Standard 6 Stages -88-100 -89-100 -88-100CONDENSERS - HIGH EFFICIENCY FIN AND TUBE TYPE WITH INTEGRAL SUBCOOLINGCoil Face Area,Sq. Ft. 87 87 87 87 87 87Coil Face Area, (m2) (8.1) (8.1) (8.1) (8.1) (8.1) (8.1)Finned Height x Finned Length, In. 100x125.9 100x125.9 100x125.9 100x125.9 100x125.9 100x125.9Finned Height x Finned Length, (mm) 2540 x 3183 2540 x 3183 2540 x 3183 2540 x 3183 2540 x 3183 2540 x 3183Fins Per Inch x Rows Deep 16 x 3 16 x 3 16 x 3 16 x 3 16 x 3 16 x 3Pumpdown Capacity @ 90% Full (lbs) 162 162 162 162 162 162Pumpdown Capacity @ 90% Full (kgs) (73.5) (73.5) (73.5) (73.5) (73.5) (73.5)Maximum Relief Valve Pressure Setting, psig (kPa) 450 (3103) 450 (3103) 450 (3103) 450 (3103) 450 (3103) 450 (3103)CONDENSER FANS - DIRECT DRIVE PROPELLER TYPENumber Of Fans - Fan Diameter, In. (mm) 6 - 28 (712) 6 - 28 (712) 6 - 28 (712)Number Of Motors - HP (kW) 6 - 2.0 (1.5) 6 - 2.0 (1.5) 6 - 2.0 (1.5)Fan And Motor RPM, 60Hz 1140 1140 114060 Hz Fan Tip Speed, FPM (M/Sec) 8357 (35.4) 8357 (35.4) 8357 (35.4)60 Hz Total Unit Airflow, CFM (M3/sec) 61200 (28.9) 61200 (28.9) 61200 (28.9)NOTES:

1. Nominal capacity based on 95°F ambient air and 45°F saturated suction temperature, no refrigerant line loss.2. Does not include evaporator, suction or liquid line charge. Unit shipped with R-22 holding charge.3. Units with 1.0 Hp Fan Motors, Uses 1.5 Hp Fan Motors when unit is 380V / 60 Hz and 575V / 60Hz.

CDE Evaporators

Model Number, CDE 1204-2 1204-1 1255-1 1455-1Operating Weight Lbs (kg) 777 (352) 777 (352) 997 (452) 1126 (511)Shipping Weight Lbs (kg) 745 (338) 745 (338) 925 (420) 1025 (465Diameter, in. - Length, Ft. 12.75- 04 12.75- 04 12.75 - 5.5 14 - 5.5Diameter, (mm) - Length, (mm) 324 - 1220 324 - 1220 324 - 1676 356 - 1676Water Volume, Gallons, (L) 12.8 (48.5) 12.8 (48.5) 17.6 (66.6) 21.2 (80.3)Refrigerant Volume, cu. Ft. (cu. m.) 1.25 (0353) 1.25 (0353) 1.69 (.0478) 2.33 (.0659)Operating Charge, Per System, Lbs (kg) 2.8 (1.27) 2.8 (1.27) 3.8 (1.72) 5.2 (2.36)Maximum Water Pressure, psig (kPa) 175 (1207) 175 (1207) 175 (1207) 175 (1207)Maximum Refrigerant Working Pressure, psig (kPa) 225 (1552) 225 (1552) 225 (1552) 225 (1552)Water Inlet / Outlet Victaulic Connections, In. (mm) 4 (101.6) 5 (141.3) 5 (141.3) 5 (141.3)Drain - NPT int, In. (mm) .375 (9.5) .375 (9.5) .375 (9.5) .375 (9.5)Vent - NPT int, In. (mm) .375 (9.5) .375 (9.5) .375 (9.5) .375 (9.5)


Dimensional Data, ACR-AS

Figure 7, Dimensions, ACR 060AS - 075AS

ACR COMPRESSOR # 1 (SUCTION #1) COMPRESSOR # 2 (SUCTION #2)MODEL inch (mm) inch (mm)

NUMBER A B C D E F G H060AS 86.2 (2190) 81.7 (2075) 50.84 (1391) 20.88 (597) 23.52 (597) 10.09 (256) 20.88 (597) 23.52 (597)065AS 86.2 (2190) 81.7 (2075) 50.09 (1272) 20.88 (597) 23.52 (597) 10.09 (256) 20.88 (597) 23.52 (597)070AS 86.2 (2190) 81.7 (2075) 50.09 (1272) 20.88 (597) 23.52 (597) 9.34 (237) 20.88 (597) 23.52 (597)075AS 23.52 (597) 91.7 (2329) 49.34 (1253) 20.88 (597) 23.52 (597) 9.34 (237) 20.88 (597) 23.52 (597)

ACR CENTER OF GRAVITY UNIT WEIGHTS ADDITIONAL WEIGHT FORMODEL inch (mm) lb (kgs) UNITS W/COPPER FIN COILS

NUMBER X Y Z OPERATING SHIPPING lb (kgs)060AS 43.4 (1102) 36.4 (925) 40.7 (1034) 3642 (1652) 3550 (1610) 665 (300)065AS 43.4 (1102) 36.4 (925) 40.6 (1031) 3712 (1684) 36.20 (1642) 665 (300)070AS 43.4 (1102) 36.5 (927) 40.6 (1031) 3745 (1699) 3635 (1649) 665 (300)075AS 44.0 (1118) 37.4 (950) 43.2 (1097) 3935 (1785) 3825 (1735) 830 (375)


Figure 8, Dimensions, ACR 080AS - 120AS

ACR COMPRESSOR # 1 (SUCTION #1) COMPRESSOR # 2 (SUCTION #2)MODEL inch (mm) inch (mm)

NUMBER A B C D E F G H080AS 96.2 (2444) 91.7 (2329) 88.5 (2248) 20.9 (531) 25.5 (648) 48.5 (1232) 20.9 (531) 25.5 (648)090AS 96.2 (2444) 91.7 (2329) 88.5 (2248) 20.9 (531) 25.5 (648) 49.0 (1245) 23.9 (608) 27.8 (707)100AS 96.2 (2444) 91.7 (2329) 86.0 (2184) 23.9 (608) 27.8 (707) 49.0 (1245) 23.9 (608) 27.8 (707)110AS 96.2 (2444) 91.7 (2329) 86.0 (2184) 23.9 (608) 27.8 (707) 49.0 (1245) 23.9 (608) 27.8 (707)120AS 96.2 (2444) 91.7 (2329) 86.0 (2184) 23.9 (608) 27.8 (707) 49.0 (1245) 23.9 (608) 27.8 (707)

ACR CENTER OF GRAVITY UNIT WEIGHTS ADDITIONAL WEIGHT FORMODEL inch (mm) lb (kgs) UNITS W/COPPER FIN COILS

NUMBER X Y Z OPERATING SHIPPING lb (kgs)080AS 59.8 (1519) 37.5 (953) 41.5 (1054) 4670 (2118) 4510 (2045) 1245 (565)090AS 59.8 (1519) 36.9 (937) 40.8 (1036) 4905 (2224) 4745 (2152) 1245 (565)100AS 59.8 (1519) 37.3 (947) 40.9 (1039) 5224 (2370) 5060 (2295) 1245 (565)110AS 59.8 (1519) 37.3 (947) 39.3 (998) 5234 (2374) 5070 (2300) 1245 (565)120AS 59.8 (1519) 37.3 (947) 39.3 (998) 5238 (2376) 5070 (2300) 1245 (565)


CDE EvaporatorsFigure 9, CDE 1204-2 - 1455-1

CDE WATER CONNECTION REFRIGERANT CONNECTIONMODEL inch (mm) inch (mm)

NUMBER C L P T M NCDE-1204-2 39.3 (998) 9.5 (241) 4.0 (102) 5.4 (137) 2 1/8 (54) 1 3/8 (35)CDE-1204-1 36.0 (914) 9.5 (241) 5.0 (127) 7.0 (178) 2 1/8 (54) 1 3/8 (35)CDE-1255-1 54 (1372) 11.0 (278) 5.0 (127) 7.0 (178) 2 1/8 (54) 1 3/8 (35)CDE-1455-1 54 (1372) 11.0 (278) 5.0 (127) 7.0 (178) 2 1/8 (54) 1 3/8 (35)

CDE DIMENSIONAL DATAMODEL inch (mm)

NUMBER A B D E F GCDE-1204-2 53.5 (1359) 17.5 (445) 7.1 (180) 17.5 (445) 12.1 (307) 2.3 (58)CDE-1204-1 53.5 (1359) 17.5 (445) 8.8 (224) 17.5 (445) 12.1 (307) 2.3 (58)CDE-1255-1 71.5 (1816) 17.5 (445) 8.8 (224) 19.0 (483) 12.1 (307) 3.0 (76)CDE-1455-1 71.5 (1816) 19.1 (485) 8.8 (224) 19.0 (483) 12.1 (307) 3.0 (76)

CDEMODEL

DIMENSIONAL DATAinch (mm)

NUMBER K R S U V W AA BBCDE-1204-2 3.0 (76 50.0 (1270) 52 (1321) 1.8 (45) 2.8 (71) 16.0 (406 ---- 14.0 (356)CDE-1204-1 3.0 (76 50.0 (1270) 52 (1321) 1.8 (45) 2.8 (71) 16.0 (406 ---- 14.0 (356)CDE-1255-1 3.0 (76) 68.0 (1727) 70.0 (1778) 1.8 (45) 2.8 (71) 16.0 (406) ---- 14.0 (356)CDE-1455-1 3.0 (76) 68.0 (1727) 70.0 (1778) 1.8 (45) 2.8 (71) 17.6 (447) ---- 14.0 (356)

NOTE: CDE physical data can be found in the Physical Data


Application Data

ClearancesDo not block the flow ofair to and from thecondenser coil.Restricting airflow orallowing air recirculationwill result in a decreasein unit performance andefficiency becausedischarge pressures areincreased. There must beno obstruction above theunit that would deflectdischarge air downwardwhere it could berecirculated back to theinlet of the condensercoil. The condenser fansare propeller type andwill not operate withductwork on the fanoutlet.

Install the unit withenough side clearance forair entrance to the coiland for servicing. Provideservice access to theevaporator, compressors,electrical control paneland piping components.

Do not allow debris toaccumulate near the unit.Air movement may drawdebris into the condensercoil causing coilstarvation. Give specialconsideration to lowambient operation wheresnow can accumulate.Keep condenser coils andfan discharge free ofsnow or otherobstructions to permitadequate airflow forproper unit operation.

Figure 10, Clearances


Unit PlacementACR condensing units are designed for outdoor applications and can be mounted either on a roof or atground level. For roof mounted applications, install the unit on a steel channel or I-beam frame tosupport the unit above the roof. For ground level applications, install the unit on a substantial basethat will not settle. A one-piece concrete slab with footings extended below the frost line isrecommended. Be sure the foundation is level (within 1/2"(13mm) over its length and width). Thefoundation must be strong enough to support the operating weights listed in Table 14 through Table16.

On ground level applications protect fins against vandalism using the optional base guards or byerecting a screen fence. It must allow free flow of air to the condenser coil for proper unit operation.

The remote evaporator has a resistance heater cable and can be used outdoors down to -20°F with fieldapplied piping freeze protection and wiring to the heater.

Sound IsolationThe low sound level of ACR units is sufficient for most applications. However, there will beapplications where sound generation may be an issue. The most effective isolation method is to locatethe unit away from sound sensitive areas. Avoid locations beneath windows or between structureswhere normal operating sounds may be objectionable. Reduce structurally transmitted sound byisolating water lines, electrical conduit and the unit itself. Use wall sleeves and rubber isolated pipinghangers to reduce transmission of water or pump noise into occupied spaces. Use flexible electricalconduit to isolate sound through electrical conduit. Spring isolators are effective in reducing the lowamplitude sound generated by scroll compressors and for unit isolation in sound sensitive areas.

Typical Chilled Water Piping (Where Applicable)Flush the system water piping thoroughly before making connections to the unit evaporator. Install astrainer of 40 mesh in the return water line before the inlet to the chiller. Design the water piping sothe chilled water circulating pump discharges into the evaporator inlet.

Connect the return water line to the evaporator inlet connection (the connection closest to thecompressors). Connect the supply water line to the evaporator outlet connection.

Install a flow switch in the horizontal piping of the supply (evaporator outlet) water line.

Provide drain connections at low points in the system to permit complete drainage of the system.Locate air vents at the high points in the system to purge air out of the system. A vent connection ontop of the evaporator vessel allows air to be purged out of the evaporator. Purge air from the watersystem before unit start-up to ensure adequate flow through the evaporator.

Install pressure gauges in the inlet and outlet water lines to the evaporator to measure pressure dropthrough the evaporator and compare to flow as shown in Figure 4. Vibration eliminators arerecommended in both the supply and return water lines.

If located in an area subject to freezing, insulate chilled water piping to reduce heat loss and preventcondensation. Outdoor chillers not running in the winter should have their water systems thoroughlydrained to protect against freezing. If the chiller operates year round, or if the system is not drained forthe winter, protect the chilled water piping exposed to outdoor temperature against freezing. Wrap thelines with a heater cable and add proper amount of glycol to the system to further protect the system.

The total water volume in the system should be sufficient to prevent frequent “on-off” cycling.Turnover rate should not be less than 15 minutes for normal variable cooling loads. Turnover rate forprocess cooling or a constant load, should not be less than 6 minutes.

The thermostat sensor is factory mounted in the leaving water well. If an optional high return watersensor is provided, install sensor bulb in a field supplied tee or strap to the outside of the water line.


Figure 11, Typical chilled water piping

Series Compared to Parallel OperationConsider system pressure drop when designing the water piping. Parallel piped systems have half ofthe total system flow going through the evaporator of each chiller, reducing the individual unit andtotal system pressure drop.

Series piped evaporators require that the total system water flows through both evaporators. Not onlyis the pressure drop through each evaporator increased but the pressure drops must be added togetherto obtain the total evaporator pressure drop. Series piped evaporators normally require largercirculating pumps for the chilled water system.

Temperature and Water Flow LimitationsMcQuay CDE evaporators are designed to operate in temperatures from 40°F (-4.5°C) to 115°F(46°C). Evaporator flow rates below the minimum values may result in laminar flow causing freeze-up problems, scaling and poor control. Flow rates above the maximum values will result inunacceptable pressure drops and may cause excessive nozzle and tube erosion, potentially leading tofailure. See Figure 4 for acceptable values.

Refrigerant Piping

IntroductionProper refrigerant piping can represent the difference between a reliable, trouble free system andmonths or years of inefficient, problematic performance. The following section is based on ASHRAEinformation.

System concerns related to piping are:

1. Refrigerant pressure drop

2. Solid liquid feed to the expansion valve(s)

3. Continuous oil return

Of the three listed, the most important and least understood is number 3. “Continuous oil return”. Thefailure of oil to return at or close to the rate of displacement from the compressor can result in oiltrapping and ultimate compressor failure.


On the other hand, the instantaneous return of a large volume of compressor oil, as a slug, can beequally damaging to a compressor.

All compressors displace some oil during operation. Reciprocating compressors displace more thancentrifugals, scroll and McQuay screw compressors since oil is carried into compressor cylinders withsuction gas; and oil present on cylinder walls is entrained by that same gas as it is being compressed.The sum of the two is then pumped into the discharge piping.

Also more oil is displaced at start-up of a compressor than occurs during a normal running period.Thus, if a compressor experiences excessive starts because of recycling pumpdown control, the largerquantity of oil pumped out is trapped in the condenser with the refrigerant charge, and may not returnregardless of the adequacy of the piping system.

A similar problem to a lesser extent occurs when the equipment is oversized for the available coolingload.

In short, extreme care should be exercised to assure that both piping and controls are suitable forthe application such that displaced oil is returned to the compressor moderately. Note, too, thatoil loss to the system can be due to a hang up in the evaporator, as well as in the piping.

SUCTION LINESMcQuay recommends the use of ASHRAE for guidelines in sizing and routing piping with oneexception. See the 1998 ASHRAE Handbook Refrigeration Edition, Chapter 2 for tables andguidelines. The single exception is to the piping of direct expansion cooling coils located above thecompressors. In all cases, regardless of whether the equipment has pumpdown control or not, a trap inthe suction line equal to the height of the coil section is recommended. In its absence, upon a powerfailure, all of the liquid in the coil will fall by gravity to the compressor below.

Suction line gas velocities may range between 900 and 4000 feet per minute. Consideration should begiven to the possibility of objectionable noise in or adjacent to occupied space. Where this is aconcern, gas velocities on the low side are recommended.

Routing must also take into account the requirement established in the latest ANSI/ASHRAE 15.

To size the suction line, determine:

a. The maximum tons for the circuit.

b. The actual length in feet.

c. The equivalent length contributed by elbows, fittings, valves or other refrigerant specialties. ASHRAE Tables 2-10, 11 & 12

d. If a vertical riser exists including the trap at the coil, determine the minimum tons for the circuit.

Add b and c above to obtain the total equivalent feet. Use ASHRAE Table 3 (for R22) or Table 4 (forR134a). Suction line selections are based upon the pressure equivalent of a 2ºF loss per 100equivalent feet.

Select a line size that displays an equal or slightly larger tons then that determined in a) above.

To determine the actual line loss:

1. Modify the table tons by the value in Note 4 of Table 3 or 4 for the design condensingtemperature.

2. Use the formula in Note 3 to calculate the line loss in terms of the saturation temperature.

3. Convert the saturation temperature loss calculated to a pressure drop equivalent using the (Delta)listed in the table for the comparable delta temperature.


Caution: Excessive pressure drop is undesirable because:

• It reduces available compressor capacity.

• It increases power consumed from the net tons realized.

• It may affect the performance of both the evaporator and the expansion valve previously selectedfor the application.

Note: The line loss calculated, expressed in temperature, or PSID pressure drop will be used toestablish the temperature required at the evaporator to produce the required cooling, as well as, thesuction pressure that the compressor must operate at to deliver the required capacity.

Having selected the suction line size, based upon total equivalent length and maximum tons, verify theline size selected will maintain entrainment of the lubricating oil up any vertical risers at the minimumtons for the circuit. See d above, and ASHRAE Table 2-13.

Note: If the line size selected will not maintain satisfactory oil return in a suction riser, the followingoptions are available:

The vertical length can be sized smaller to accommodate the lower circuit tons at reduced load.

The minimum compressor capacity can be increased by eliminating the lowest step of compressorcapacity.

Hot gas bypass can be introduced at the distributor to the evaporator, increasing the volume of gasavailable in the suction line to entrain the oil.

An oil separator may be installed in the discharge line.

With reciprocating compressor units only, and only as a last resort, double suction risers can beutilized. Since a double suction riser works by providing an oil trap to assure the return of some oil,with refrigerant, up the smaller diameter line, a) the trap must be as small as possible, b) there must notbe multiple traps, and c) whenever double risers are used in a suction line, a suction accumulator witha controlled oil return must be installed in the line ahead of the compressor.

In horizontal refrigerant gas lines, oil return to compressors is assured by sizing lines at a velocityabove the minimum recommended and pitching the lines in the direction of refrigerant flow.

SIZING A DOUBLE RISERAt maximum circuit tons, the line size should be selected from the table based upon the recommendedmaximum line loss.

With the minimum tons known, a smaller line size should be selected from ASHRAE Chapter 2, Table13 or 14 capable of entraining oil at the reduced tons. The smaller sized line should be the oneinstalled to be always active.

The net internal area of this smaller sized line (see Table 13 or 14) should be deducted from the area ofthe size selected in paragraph 1) immediately above. The remainder represents the area of the otherriser. From Table 13 or 14, select a line size with an area equal, or close, to the calculated net area.The combination of these two risers will provide the required performance at full circuit tons. Theline selected for the minimum load should always be active; and both lines should enter the overheadhorizontal line in a manner to prevent spillage of oil back down the other riser.

LONG VERTICAL RISER INSTALLATIONWhere job conditions require refrigerant gas lifts of more than 25 feet, McQuay recommends theinstallation of a short trap half-way up the riser or at not more than 20 feet intervals. These traps arerequired to capture and hold small quantities of oil during off cycles.


DX Coil PipingThe following should be designed into DX coil refrigerant piping:

• Split coils should have a solenoid valve in each liquid feed line.

• Shut down the top coil with capacity reduction on the condensing unit.

• Feed hot gas bypass (if used) to both distributors through a low pressure drop check valve aheadof the distributor.

• Install the expansion valve bulbs on the horizontal line ahead of the traps.

Figure 12, Typical DX Coil Piping (Hot Gas Bypass Not shown)

Condensing Unit Above Coil Condensing Unit Below Coil

EXPANSION VALVECONTROL BULBSTRAP TO LINEAND INSULATE

SUCTION TRAPSHORT ASFITTINGS PERMIT

LIQUID TOCOIL

SUCTION

PITCH TO

COMPRESSOR

Condensing Unit Above Coil Condensing Unit Below Coil

LIQUID TOCOIL

SUCTION PITCH

TO ONE COMPRESSOR ONLY

SUCTION TRAPSHORT ASFITTINGS PERMIT

EXPANSION VALVECONTROL BULBSSTRAP TO LINEAND INSULATE

LIQUID TOCOIL

EXPANSION VALVECONTROL BULBSTRAP TO LINE

A

B

DUAL RISERSUCTION TRAPSHORT AS

SUCTION PITCH

TO ONE COMPRESSOR ONLY


Liquid LinesLiquid lines are generally sized for 1º to 2ºF line losses or their equivalent in pressure drop. Actualselection can vary based upon the pressure drop expected from refrigerant specialties such assolenoids, refrigerant driers, valves, etc. piping lifts or risers and the amount of condenser sub-coolingexpected.

The principal concern in sizing and routing liquid lines is assurance that liquid is present in the line atstart-up of the compressor, and that liquid and not vapor is available at the inlet to the expansion valveduring system operation.

Liquid may not be available in a liquid line at start-up if:

• The solenoid valve is located adjacent to the condenser or condensing unit; remote from theexpansion valve.

• An excessive length of liquid line is located in a heated ambient and the application permitsmigration of the refrigerant to a cold air cooled condenser.

• Liquid refrigerant is permitted to gravitate from the liquid line to the condenser because of therelative location of components.

• Liquid line solenoid valves should be located adjacent to the expansion valve with possibly only asight glass interposing the two.

In the event 2) or 3) above are possible, the application should include a check valve at the condenserend of the liquid line. The check valve should be a low pressure drop valve, and since the line betweenthe check valve and the solenoid valve can be comparable to a pressure vessel it should include apressure relief device, relieving from the line side to the condenser side of the circuit. The relief canbe sized for a pressure differential from 80 to 180 psi, but not more than 180 psi, and should be auto-resetting as the pressure is relieved.

CAUTION: The liquid line should not include a check valve unless the line also includes anautomatic resetting pressure relief device.

CAUTION: If the relief device being used is relieving from the line to the condenser side of the checkvalve, the maximum desirable pressure differential with R-22 refrigerant is 180 psi. With 134a, 100psi.

If liquid lines are short, they may be of smaller diameter than the size indicated in the ASHRAERefrigerant Handbook, 1998 Edition, Chapter 2, Table 3 or 4. As indicated above, the designer mustsize the liquid line to assure that pure liquid will reach the inlet of the expansion valve. If thecondenser is sized to produce 10ºF of subcooling, and each degree represents 3.05 psi with R-22 (or2.2. psi with R-134a), the liquid line and its refrigerant specialties may have pressure losses totaling10 x 3.05 psi (or 10 x 2.2) and still satisfy the objective of delivering pure liquid to the expansionvalve.

In calculating the pressure losses, or gains, note that each foot of rise in a liquid line results in anapproximate 0.5 psi loss. Thus a 10 foot rise represent 5 pounds per square inch loss in refrigerantpressure, or the equivalent of 1.6ºF subcooling with R-22. Total line losses will include values forline friction, equivalents for valves and elbows and pressure losses from manufacturers’ catalogs fordriers, solenoids, sight glasses, etc.

In estimating condenser subcooling, note that saturated condensing pressure should be read, orestimated, at the same point in the system where the liquid refrigerant temperature is obtained. Thatcondensing pressure is not the discharge pressure read at the compressor outlet. Because it is less, thenet value of subcooling will be lower than might otherwise be assumed.


Where rises in liquid lines result in a 0.5 PSI loss per foot of lift, a drop in the liquid line results in arise in the refrigerant pressure. A substantial drop in the liquid line can assure the existence of pureliquid at the valve. If it is a substantial increase because of a large drop, the expansion valve selectionmust be re-checked to confirm that the valve to be used is not radically oversized.

Liquid Lines from Condensers to ReceiversReceivers in a refrigerant system have both liquid and gas contained within the same vessel. In air-cooled condenser applications, the condensing temperature can change rapidly resulting in therequirement for more liquid at a lower temperature and pressure to be introduced into the receiver.

In order for this flow of lower temperature and pressure liquid refrigerant to enter the receiver, 1) thereceiver must be located below the condenser outlet with no restrictions in the line, and 2) the liquidline connecting the condenser and the receiver must be sized for a maximum velocity of 100 fpm.Piping sizes for this are shown in the ASHRAE tables.

Note: If the interconnecting piping described above contains a Seasontrol back-flooding type headpressure control valve representing a restriction in the liquid line, a separate vent from the top of thereceiver to the discharge line entering the condenser is required.

Liquid Line ComponentsTo assist in laying out and specifying split systems, the following recommended (or equal) componentscan be used.

Table 17, Liquid Line Components for Dual Independent Refrigerant CircuitsNom.R-22 Sporlan Part Number Shown - (Equivalents Are Acceptable)

Unit Refrigerant Tons Filter Solenoid Sight Expansion Unit Conn.Model Circuit (mbh) Drier Valve Glass Valve In/Out

ACR 060A #1 335 C-967 E19S270 SA-17S OVE-30 7/8-1-3/8#2 368 C-967 E19S270 SA-17S OVE-30 7/8-1-3/8

ACR 065A #1 & #2 368 C-967 E19S270 SA-17S OVE-30 7/8-1-3/8

ACR 070A #1 379 C-967 E25S270 SA-17S OVE-30 7/8-1-3/8#2 436 C-967 E25S270 SA-17S OVE-40 7/8-1-3/8

ACR 075A #1 & #2 436 C-969 E25S290 SA-19S OVE-40 1 1/8-1-3/8

ACR 080 #1 & #2 480 C-969 E25S290 SA-19S OVE-40 1 1/8-1-3/8

ACR 090A #1 490 C-969 E25S290 SA-19S OVE-40 1 1/8-1-3/8#2 589 C-1449 E25S290 SA-19S OVE-55 1 1/8-1-3/8

ACR 100A #1 & #2 589 C-1449 E25S290 SA-19S OVE-55 1 1/8-1-3/8

ACR 110A #1 589 C-1449 E25S290 SA-19S OVE-55 1 1/8-1-3/8#2 689 C-1449 E25S290 SA-19S OVE-70 1 1/8-1-3/8

ACR 120A #1 & #2 689 C-1449 E25S290 SA-19S OVE-70 1 1/8-1-3/8


Optional Features

Hot Gas BypassHot gas bypass permits unit operation down to 10% of full load capacity. This field installed optionincludes a hot gas bypass valve, solenoid valve, and manual shutoff valve for each refrigerant circuit.

GaugesOptional factory mounted gauges include high side and low side refrigerant gauges for each refrigerantcircuit.

Protective Base GuardsOptional factory installed vinyl-coated welded wire base guards provide all-around protection on thelower portion of the unit on ground level installations.

Hail/Wind GuardsField installed protection for the fins in areas subjected to hail storms. Also important for applicationsoperating at low ambient air temperatures and exposed to wind across the coil greater than 5 mph.

Copper Fin Condenser CoilsCopper fin condenser coils are available as an option on all models.

Aluminum or Copper Fins with Protective CoatingCoating is Electro Fin flexible dip and bake epoxy coating providing corrosion resistance to a widerange of chemicals and salt water.

Disconnect Switch with Through-the-Door HandleA field installed service use, nonfused disconnect switch (mounted inside the power section of controlbox) with a through-the-door handle is available with single point power supply. Requires fieldmodification to panel door.

Totally Enclosed Condenser Fan MotorsAvailable on all fan motors for standard ambient air operation. If the low ambient SpeedTrol option isselected, the variable speed lead condenser fan motor on each refrigerant circuit will be a protectedcommercial-duty single phase open drip-proof motor.

Circuit BreakersFactory installed circuit breakers are available on units with single point power supply. This optionprovides unit installed compressor short circuit protection and makes field servicing easier by notrequiring access to a remote disconnect switch.

Phase Loss/Voltage ProtectionPhase loss with under/over voltage protection and multiple LED indication of fault type is available asa factory installed option to guard against compressor motor burnout:


Water Flow SwitchA water flow switch is available for field installation in the chilled water piping to prevent evaporatorfreeze-up under low or no flow conditions. Terminals are provided in the unit control center for fieldhook-up of the water flow safety switch. If this option is not ordered with the unit, then a fieldsupplied water flow switch is required.

Vibration IsolatorsSpring vibration isolators are available for field installation to reduce vibration transmission throughthe unit base. A total of four per unit is required.


ACR-AS Specification

SECTION 15XXXAIR-COOLED CONDENSING UNITS WITH

RECIPROCATING COMPRESSORACR 060AS - ACR 120AS

PART 1 - GENERAL1.01 SUMMARY

Section includes design, performance criteria, refrigerants, controls, and installationrequirements for air-cooled reciprocating compressor chillers.

1.02 REFERENCES

Comply with applicable Standards/Codes of ANSI/ASHRAE 15, ETL, cETL, ASME Section

VIII, NEC, ASHRAE Standard 90.1, and OSHA as adopted by the State.

1.03 SUBMITTALS

A. Submit shop drawings and product data in accordance with the specifications.

B. Submittals shall include the following:

1. Dimensioned plan and elevation view drawings, required clearances, and

location of all field connections.

2. Summary of all auxiliary utility requirements such as: electricity, water,

compressed air, etc. Summary shall indicate quality and quantity of each

required utility.

3. Single line schematic drawing of the power field hookup requirements,

indicating all items which are furnished.

4. Schematic diagrams of control system indicating points for field

interface/connection.

5. Diagram shall fully delineate field and factory wiring.

6. Installation manuals.

7. Drawing of refrigerant piping

1.04 QUALITY ASSURANCE

A. Qualifications: Equipment manufacturer must specialize in the manufacture of the

products specified and have five years experience with the equipment and refrigerant

offered.

B. Regulatory Requirements: Comply with the codes and standards specified.

C Chiller manufacturer plant must be ISO9002 Registered.


1.05 DELIVERY AND HANDLING

A. The condensing units shall be delivered to the job site as a single component

consisting of housing, compressors, condensers, and controls, less capacity control

staging which will be furnished and installed by the contractor.

B. Comply with the manufacturers instructions for rigging and handling equipment.

1.06. WARRANTYThe equipment manufacturer’s warranty shall be for a period of one year from date of start-up

but not more than 18 months from shipment. The warranty shall cover material and

workmanship that prove defective within the above period, excluding refrigerant.

1.07 MAINTENANCEMaintenance of the chillers shall be the responsibility of the owner and performed in

accordance with the manufacturer’s instructions.

PART 2--PRODUCTS

2.01 ACCEPTABLE MANUFACTURERS

A. McQuay International

B. (Approved Equal)

2.02 UNIT DESCRIPTION

Provide and install as shown on the plans factory assembled, and factory run tested, air-

cooled reciprocating compressor condensing units,

2.03 DESIGN REQUIREMENTS

A. General: Provide a complete air-cooled reciprocating compressor condensing unit as

specified herein and as shown on the drawings. The unit shall be in accordance with

the standards referenced in section 1.02 and any local codes in effect.

B. Performance: Refer to the schedule of performance on the drawings. The chiller

shall be capable of stable operation to a minimum of 30 percent of full load without

hot gas bypass.

C. Acoustics: Sound pressure levels for the unit shall not exceed the following

specified levels. The manufacturer shall provide the necessary sound treatment to

meet these levels if required. Sound data shall be provided with the quotation and be

measured at 30 feet from the unit and one meter above the unit base line.

Octave Band63 125 250 500 1000 2000 4000 8000 dBA

___ ____ ____ ____ ____ ____ ____ ____ _____


2.04 UNIT COMPONENTS

A. Structure: The unit shall have a heavy duty fully painted formed steel, full length

and width base. The base, condenser support legs and all other sheet metal

components shall be galvanized, phosphorized, and painted. Coils shall be protected

with wire grilles or louvers. Adequate space shall be provided to service or remove

all components.

B. Compressors: The compressors shall be accessible hermetic reciprocating type with

suction and discharge service valves, crankcase oil heater and suction strainer.

Compressors shall have a forced feed lubrication system with a reversible oil pump

and initial oil charge. The compressor motor shall be refrigerant gas cooled, high

torque, hermetic induction type, four-pole, with inherent thermal protection on all

three phases and shall be mounted on RIS vibration isolator pads.

C. Condenser: The condenser coils shall consist of 3/8 inch (10mm) seamless copper

tubes mechanically bonded into rippled plate type fins. The fins shall have full

drawn collars to completely cover the tubes. A subcooling coil shall be an integral

part of the main condenser coil. Condenser fans shall be propeller type arranged for

vertical air discharge and individually driven by direct drive fan motors. Each fan

shall be in its own compartment to eliminate cross flow of condenser air during fan

cycling and shall be equipped with a heavy-gauge vinyl coated fan guard. Fan

motors shall be weather protected, three-phase, direct-drive, 1140 rpm, open drip-

proof type. Speed controlled fan motors shall be single-phase, direct drive, 1140

rpm. Exterior coil surfaces shall be protected by coil guards.

E. Refrigerant Circuit: The unit shall be factory equipped with suction and liquid

shutoff valves, relief valves, charging valves and discharge mufflers..

F. Control System: A centrally located weatherproof control panel shall contain the

field power connection points, control interlock terminals, and control system.

Power and starting components shall include factory fusing of fan motors and

control circuit; individual contactors for each fan motor, solid-state start timer,

solid-state three-phase motor overload protection, inherent fan motor overload

protection and unit power terminal blocks for connection to remote disconnect

switch. Hinged access doors shall be lockable. Barrier panels are required to

protect against accidental contact with line voltage when accessing the control

system. Capacity control for staging unloading shall be supplied and installed by the

contractor.

G. The refrigerant discharge pressure shall be controlled by a FanTrol system cycling

condenser fans based on discharge pressure and shall be operational 40°F (4.4°C).

- OR -


The refrigerant discharge pressure shall be controlled by a SpeedTrol control

employing both fan cycling and fan speed control and allow operation to

0°F (-18°C).

2.05 OPTIONS AND ACCESSORIES

The following options are to be included:

• Hot gas bypass on all circuits, field installed

• Low ambient, variable speed, head pressure control to 0°F (-17.8°C)

• Copper fin condenser coils

• Wire mesh guards for base section protection

• Chilled water flow switch, field mounted and wired to terminals in the control panel

• Spring vibration isolators for field installation

• Factory mounted refrigerant pressure gauges for each circuit

• Factory installed nonfused disconnect switch, with through-the-door handle, mounted in

the unit control panel

• Factory installed circuit breaker to provide unit short circuit protection

• Phase loss with under/over voltage protection and with LED indication of the fault type.

PART 3 - EXECUTION

3.01 INSTALLATION

A. Install in strict accordance with manufacturer’s requirements, shop drawings, and

contract documents.

B. Adjust and level chiller outdoor and indoor sections on supports.

C. Coordinate electrical installation with electrical contractor.

D Coordinate controls with control contractor.

E. Provide all appurtenances required to ensure a fully operational and functional

chiller system.

3.02 START-UP

A. Leak test, evacuate and charge system with proper charge of refrigerant and oil.

B. Provide testing, and starting of machine, and instruct the Owner in its proper

operation and maintenance.

END OF SECTION

Post Office Box 2510, Staunton, Virginia USA (540) 248-0711

AIR-COOLED, RECIPROCATING CONDENSING UNITS

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