Installation & Maintenance Data

IM 548-3

Group: Chillers

Part Number: 573864Y-01

Date: October 1996

SeasonPak

®

Packaged Air Cooled Water Chiller with Screw Compressor

Models ALS-125A thru 380A

©1996 McQuay International

®

Table of Contents

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

General Description ....................................................... 3

Nomenclature ................................................................. 3

Inspection ...................................................................... 3

Installation and Start-up ............................................... 3-17

Handling ..................................................................... 3-6

Location ......................................................................... 6

Service Access .............................................................. 6-9

Vibration Isolators .................................................. 10-12

Water Piping ........................................................... 13-14

Flow Switch .................................................................. 14

Water Connections ....................................................... 15

Refrigerant Charge ....................................................... 15

Glycol Solutions ...................................................... 15-16

Evaporator Water Flow and Pressure Drop ............. 16-17

Physical Data .............................................................. 17-20

Major Components .......................................................... 21

Compressor Staging Sequence .................................... 21-23

Dimensional Data ...................................................... 24-27

Field Wiring ................................................................ 28-46

General ......................................................................... 28

Overload Dial Setting ................................................... 29

Wire Sizing Ampacities ............................................ 30-35

Compressor and Condenser Fan Motors ................. 35-38

Customer Wiring ..................................................... 39-43

Electrical Data Notes .................................................... 44

Electrical Legend .......................................................... 45

Evaporator Freeze Protection ........................................ 45

Typical Field Wiring .................................................... 46

Unit Layout and Principles of Operation ................... 47-51

Major Component Locations ....................................... 47

Control Center ........................................................ 48-49

Sequence of Operation ............................................ 50-51

Refrigerant Piping Schematic ....................................... 51

Start-up and Shutdown ............................................... 52-54

Pre Start-up .................................................................. 52

Start-up ................................................................... 52-53

Temporary Shutdown ................................................... 53

Start-up After Temporary Shutdown ...................... 53-54

Extended Shutdown ..................................................... 54

System Maintenance ................................................... 54-55

General ......................................................................... 54

Compressor Maintenance ............................................. 54

Fan Motor Bearings ...................................................... 54

Electrical Terminals ...................................................... 54

Condensers ................................................................... 55

Refrigerant Sightglass .................................................... 55

Lead-Lag ....................................................................... 55

Service ......................................................................... 55-61

Compressor Solenoids .................................................. 56

Filter-Driers ............................................................. 56-57

Liquid Line Solenoid Valve .......................................... 57

Liquid Injection Solenoid Valve ................................... 57

Electronic Expansion Valve .......................................... 58

Electronic Expansion Valve Operation ......................... 59

Evaporator .................................................................... 59

Refrigerant Charging ............................................... 59-61

In Warranty Return Material Procedure ......................... 61

Compressor .................................................................. 61

Components Other Than Compressors ........................ 61

Appendix ..................................................................... 61-77

Standard Controls: .................................................. 61-62

Thermistor sensors ..................................................... 61

Sensor locations .................................................... 62-65

Liquid presence sensor ................................................ 65

High condenser pressure control .................................. 65

Mechanical high pressure safety control .................. 65-66

Compressor motor protection ...................................... 66

FanTrol head pressure control ............................... 66-68

Low ambient start ..................................................... 68

Phase/voltage monitor ................................................ 68

Compressor short cycling protection ............................. 69

Optional Controls: .................................................. 69-77

SpeedTrol head pressure control .................................. 69

Reduced inrush start .................................................. 69

Hot gas bypass ...................................................... 69-70

Wind baffles and hail guards ................................ 70-75

ALS controls, settings & functions .............................. 76

Troubleshooting chart ................................................ 77

Periodic Maintenance Log ............................................... 78

Limited Warranty ............................................................ 79

IMPORTANT

See freeze protection references under the heading “Water Piping” on page 11.

“FanTrol”, “McQuay”, “SeasonPak”, “MicroTech” and “SpeedTrol” are registered trademarks of McQuay International, Minneapolis, MN.

©1996 McQuay International. All rights reserved throughout the world.

“Bulletin illustrations cover the general appearance of McQuay International products at the time of publication and we reserve the right to make changes in design and construction at any time without notice.”

Page 2 / IM 548

Introduction

General Description

McQuay type SeasonPak ® air cooled water chillers are complete, self-contained automatic refrigerating units that include the latest in engineering components arranged to provide a compact and efficient unit. Each unit is completely assembled, factory wired, evacuated, charged, tested and comes complete and ready for installation. Each unit consists of multiple air cooled condensers with integral subcooler sections, multiple accessible semi-hermetic single-screw compressors, replaceable tube multiple circuit shell-and-tube evaporator, and complete refrigerant piping. Liquid line components included are manual liquid line shutoff valves, charging valves, filter-driers, liquid line solenoid valves, sightglass/ moisture indicators, and electronic expansion valves. Other features include compressor heaters, an evaporator heater for low ambient water freeze protection, automatic one time pumpdown of refrigerant circuit upon circuit shutdown, and an advanced fully integrated microprocessor control system.

The electrical control center includes all safety and operating controls necessary for dependable automatic operation, (the high and low pressure controls and the chiller heater thermostat are external from the electrical

control center.) Thermal overload protected condenser fan motors are fused in all three conductor legs and started by their own three-pole contactors. Compressors are protected by solid state overload protection and over temperature protection. Field installed fused disconnect offers additional protection.

Nomenclature

Air cooled

Liquid refrigerant injected

Screw compressor water chiller

A L S - 155 A

Design vintage

Nominal capacity (tons)

Inspection

When the equipment is received, all items should be carefully checked against the bill of lading to insure a complete shipment. All units should be carefully inspected for damage upon arrival. All shipping damage must be reported to the carrier and a claim must be filed with the carrier. The unit’s serial plate should be checked before unloading the unit to be sure that it agrees with the power supply available.

Physical damage to unit after acceptance is not the responsibility of McQuay International.

Note: Unit shipping and operating weights are available in the physical data tables.

Installation and Start-up

Note: Installation and maintenance are to be performed only by qualified personnel who are familiar

with local codes and regulations, and experienced with this type of equipment.

Sharp edges and coil surfaces are a potential injury hazard. Avoid contact with them.

Start-up by McQuayService is included on all units sold for installation within the USA and Canada.

Two week prior notification of start-up is required. The contractor should obtain a copy of the Start-up

Scheduled Request Form from the sales representative or from the nearest office of McQuayService.

Handling

Care should be taken to avoid rough handling or shock due to impact or dropping the unit. Do not push or pull the unit from anything other than the base, and block the pushing vehicle away from the unit to prevent damage to the sheetmetal cabinet and end frame (see Figure 1).

Never allow any part of the unit to fall during unloading or moving as this may result in serious damage.

IM 548 / Page 3

Page 4 / IM 548

To lift the unit, 2 1 /

2

" (64 mm) diameter lifting holes are provided in the base of the unit. Spreader bars and cables should be arranged to prevent damage to the condenser coils or unit cabinet (see Figures 2, 3,

4 and 5).

Figure 1. Suggested pushing arrangement

Control panel end

Blocking required across full width

Figure 2. Suggested lifting arrangement (125 thru 195)

Unit Models ALS125 thru 204

Speader bar recommended

(Use caution)

Must use these rigging holes.

(Note control box location)

Lift only as shown

Note: Number of fans may vary from this diagram, but lifting method remains the same.

Figure 3. Suggested lifting arrangement (205 thru 280)

Spreader bars must be used to prevent cabinet damage.

Locate bars above unit to clear fan grilles. Minimum distance across unit between cables or chains at bars is 90 inches.

Control box end

Unit Models ALS205 thru 280

Unit weights:

16,250 lbs. with aluminum fin coils

18,750 lbs. with copper fin coils

All (6) rigging holes must be used.

(Note control box locations)

Lift only from (6) base points as shown

Note: Number of fans may vary from this diagram, but lifting method remains the same.

Figure 4. Suggested lifting arrangement (300 thru 340)

Spreader bars must be used to prevent cabinet damage.

Locate bars above unit to clear fan grilles. Minimum distance across unit between cables or chains at bars is 90 inches.

Control box end

Unit Models ALS300 thru 340

Unit weights:

20,400 lbs. with aluminum fin coils

24,075 lbs. with copper fin coils

All (6) rigging holes must be used.

(Note control box locations)

Lift only from (6) base points as shown

Note: Number of fans may vary from this diagram, but lifting method remains the same.

IM 548 / Page 5

Figure 5. Suggested lifting arrangement (360 thru 380)

Spreader bars must be used to prevent cabinet damage.

Locate bars above unit to clear fan grilles. Minimum distance across unit between cables or chains at bars is 90 inches.

Control box end

Unit Models ALS360 thru 380

Unit weights:

22,100 lbs. with aluminum fin coils

22,506 lbs. with copper fin coils

Page 6 / IM 548

All (8) rigging holes must be used.

(Note control box locations)

Lift only from (8) base points as shown

Note: Number of fans may vary from this diagram, but lifting method remains the same.

Location

Care should be taken in the location of the unit to provide proper airflow to the condenser, minimizing effects on condensing pressure.

Due to the vertical condenser design of the ALS125A thru ALS380A chillers, it is recommended that the unit is oriented so that prevailing winds blow parallel to the unit length, thus minimizing the effects of condensing pressure on performance. If the unit is installed with no protection against prevailing winds it is recommended that wind baffles be installed.

Using less clearances than shown in Figures 6, 7 and 8 will cause discharge air recirculation to the condenser and could have a significant and detrimental effect on unit performance.

Service Access

Each end of the unit must be accessible after installation for periodic service work. Compressors, filterdriers, and manual liquid line shutoff valves are accessible on each side of the unit adjacent to the control box. High pressure and low pressure transducers are mounted on the compressor. The cooler barrel heater thermostat is located on the cooler. Compressor overloads, microprocessor, and most other operational, safety and starting controls are located in the unit control box.

On all ALS units the condenser fans and motors can be removed from the top of the unit. The complete fan/motor assembly can be removed for service. The fan blade and fan motor rain shield must be removed for access to wiring terminals at the top of the motor.

Disconnect all power to the unit while servicing condenser fan motors. Failure to do so may cause bodily injury or death.

Figure 6. Clearance requirements (125 thru 204)

4'-0" working clearance per

National Electric

Code Article

110-16

5'-0" if open fence or 50% open wall

6'-0" if solid wall

(see note 3 for pit)

No obstructions.

Recommended area required for unit operation, air flow and maintenance

10'-0" clearance for evaporator service or removal

3'-0" gate or opening centered on unit width

2'-0" min.

Field installed disconnect switch, locate so as not to block service access to unit components

3'-9" door swing

2'-0" min.

5'-0" if open fence or 50% open wall

6'-0" if solid wall

(see note 3 for pit)

Top View

Air flow.

No obstructions allowed above unit at any height

See notes 2 & 4 concerning wall height

Wall or fence

See note 6

See note 5

Elevation

Notes:

1. Minimum side clearance between two units is 12 feet.

2. Unit must not be installed in a pit or enclosure that is deeper or taller than the height of the unit unless extra clearance is provided per note 4.

3. Minimum clearance on each side is a 8 feet when installed in a pit no deeper than unit height.

4. Minimum side clearance to solid wall or building taller than unit height is 8 feet provided no solid wall above 6 feet tall is closer than 12 feet to opposite side of unit.

5. Removable post for compressor service access must not be blocked at either side of unit.

6. Do not mount electrical conduits, etc. above the side rail on either side of unit.

7. There must be no obstruction of the fan discharge.

IM 548 / Page 7

Figure 7. Clearance requirements (205 thru 280)

4'-0" working clearance per

National Electric

Code Article 110-16

5'-0" if open fence or 50% open wall

6'-0" if solid wall

(see note 3 for pit)

No obstructions.

Recommended area required for unit operation, air flow and maintenance access

8'-0" gate or access opening centered on corner of unit for evaporator removal

3'-9" door swing

Field installed disconnect switch, locate so as not to block service access to unit components

2'-0" min.

See notes 2 & 4 concerning wall height at unit sides

5'-0" if open fence or 50% open wall

6'-0" if solid wall

(see note 3 for pit)

Top View

Air Flow.

No obstructions allowed above unit at any height d

Wall or fence

See note 5

Side View

2'-0" min. for unit operation.

4'-0" min. for major component removal.

10'-0" min. for evaporator removal (see access

opening dimension above)

See note 6

Wall or fence

Notes:

1. Minimum side clearance between two units is 12 feet.

2. Unit must not be installed in a pit or enclosure that is deeper or taller than the height of the unit unless extra clearance is provided per note 4.

3. Minimum clearance on each side is a 8 feet when installed in a pit no deeper than unit height.

4. Minimum side clearance to solid wall or building taller than unit height is 8 feet provided no solid wall above 6 feet tall is closer than 12 feet to opposite side of unit.

5. Removable post for compressor service access must not be blocked at either side of unit.

6. Do not mount electrical conduits, etc. above the side rail on either side of unit.

7. There must be no obstruction of the fan discharge.

Page 8 / IM 548

Figure 8. Clearance requirements (300 thru 380)

4'-0" working clearance per

National Electric

Code Article 110-16

5'-0" if open fence or 50% open wall

6'-0" if solid wall

(see note 3 for pit)

No obstructions.

Recommended area required for unit operation, air flow and maintenance access

3'-9" door swing

Field installed disconnect switch, locate so as not to block service access to unit components

2'-0" min.

See notes 2 & 4 concerning wall height at unit sides

Wall or fence

5'-0" if open fence or 50% open wall

6'-0" if solid wall

(see note 3 for pit)

Top View

Air Flow.

No obstructions allowed above unit at any height d

See note 5

Side View

See note 5

6'-0" gate or access opening centered on corner of unit for evaporator removal

Alternate access opening at side opposite water connections

2'-0" min. for unit operation.

4'-0" min. for major component removal.

10'-0" min. for evaporator removal (see access

opening dimension above)

See note 6

Wall or fence

Notes:

1. Minimum side clearance between two units must be 12 feet.

2. Unit must not be installed in a pit that is deeper or enclosure higher than the height of the unit unless extra clearance is provided per notes 3 and 4.

3. Minimum clearance on each side is a 8 feet when installed in a pit no deeper than unit height.

4. Minimum side clearance to solid wall or building higher than unit height is 8 feet. In addition, the opposite side of the unit must be at least 12 feet away from a solid wall higher than 6 feet.

5. The removable posts for compressor or evaporator service access must not be blocked at either side of unit.

6. Do not mount electrical conduits, etc. above the side rail on either side of unit.

IM 548 / Page 9

Vibration Isolators

Vibration isolators are recommended for all roof mounted installations or wherever vibration transmission is a consideration. Figure 9 (125 thru 204), Figure 10 (205 thru 280), Figure 12 (300 thru

340) and Figure 13 (360 thru 380) show isolator locations in relation to the unit control center. Table 2

(125 thru 204), Table 3 (205 thru 280), Table 5 (300 thru 340) and Table 6 (360 thru 380) give the isolator loads at each location shown in Figures 9, 10, 12 and 13. Figure 11 gives dimensions that are required to secure each McQuay isolator section to the mounting surface.

Table 1. Vibration isolators (spring)

ALS UNIT SIZE

125-280

TYPE

CP2-32

COLOR

OF

STRIPE

MCQUAY PART

NUMBER

White 0047792932

RECOMMENDED

MAXIMUM LOAD

LBS. (KG)

2600 (1180)

Note: The same isolators are used when the chiller is

supplied with the optional copper finned condenser coils.

The spring is fully compressed at approximately 3900 lbs

(1769 kg).

Table 2. Isolator loads (125A thru 204A)

ALS

UNIT

SIZE

ISOLATOR LOADS AT EACH MOUNTING LOCATION

LBS (KG)

1 2 3 4 5 6

125A

1625 (737) 2065 (937) 1270 (576) 1625 (737) 2065 (937) 1270 (576)

140A

1680 (762) 2145 (973) 1350 (612) 1680 (762) 2145 (973) 1350 (612)

155A

1720 (780) 2205 (1000) 1410 (640) 1720 (780) 2205 (1000) 1410 (640)

170A

1730 (785) 2220 (1007) 1425 (647) 1730 (785) 2220 (1007) 1425 (647)

175A

1880 (853) 2350 (1066) 1395 (633) 1880 (853) 2350 (1066) 1395 (633)

185A

1880 (853) 2350 (1066) 1395 (633) 1880 (853) 2350 (1066) 1395 (633)

195A

1920 (871) 2440 (1107) 1440 (653) 1920 (871) 2440 (1107) 1440 (653)

204A

2081 (944) 2644 (1199) 1560 (707) 2081 (944) 2644 (1199) 1560 (707)

Table 3. Isolator loads (205 thru 280)

ALS

UNIT

SIZE

ISOLATOR LOADS AT EACH MOUNTING LOCATION

LBS (KG)

1 2 3 4 5 6 7 8 9 10

205A

1790 (812) 1840 (834) 2040 (925) 1370 (621) 950 (431) 1630 (739) 2020 (916) 1640 (744) 1650 (748) 1000 (454)

220A

1790 (812) 1850 (839) 2050 (930) 1370 (621) 950 (431) 1630 (739) 2030 (921) 1650 (748) 1660 (753) 1000 (454)

235A

1820 (825) 1880 (853) 2080 (943) 1370 (621) 960 (435) 1670 (757) 2060 (934) 1680 (762) 1660 (753) 1000 (454)

250A

1820 (825) 1880 (853) 2080 (943) 1380 (626) 960 (435) 1670 (757) 2060 (934) 1680 (762) 1670 (757) 1000 (454)

265A

1820 (825) 1880 (853) 2080 (943) 1380 (626) 960 (435) 1670 (757) 2060 (934) 1680 (762) 1670 (757) 1000 (454)

280A

1830 (830) 1890 (857) 2080 (943) 1380 (626) 960 (435) 1680 (762) 2070 (939) 1690 (766) 1670 (757) 1000 (454)

Figure 9. Isolator locations (125A thru 204A)

4

5

6

A = 13" (330 mm)

B = 95" (2413 mm)

C = 215" (5461 mm) ALS125A-155A

250" (6350 mm) ALS170A-204A

1

2 3

A

B

C

Page 10 / IM 548

Figure 10. Isolator locations (205 thru 280)

+

6

+

7

+

8

+

9

+

10

+

1

A

B

+

2

C

D

A = 13" (330 mm)

B = 95" (2413 mm)

C = 177" (4496 mm)

D = 259" (6579 mm)

E = 341" (8661 mm)

+

3

E

+

4

+

5

Figure 11. Spring flex isolator

3"

(76.2 mm)

3 ⁄

8

"(15.8mm)

1 ⁄

2

" (12.7 mm) dia.

positioning pin

7

3

⁄

4

" (196.8 mm)

9

1

⁄

4

" (234.9 mm) C-C FDTN. bolt

10 1 ⁄

2

" (266.70 mm)

5

⁄

8

" (15.8 mm)

6" free ht.

(152.4 mm)

9

⁄

16

" (14.1 mm)

Adjust mounting so that upper housing clears

1 lower housing by at least

⁄

4

" (6.3 mm) and not more than

1

⁄

2

" (12.7 mm)

1

⁄

4

" (6.3 mm) acoustical non-skid neoprene pad

Figure 12. Vibration isolator (300 thru 340)

•

1

•

3

•

5

•

7

•

9

13

2

•

82

4

•

82

6

•

82

8

•

116.7

10

•

14

Table 4. Vibration isolators (spring)

ALS UNIT SIZE

300A-340A

TYPE

CP2-32

COLOR

OF

STRIPE

MCQUAY PART

NUMBER

White 047792932

RECOMMENDED

MAXIMUM LOAD

LBS (KG)

3000 (1360)

Note:

The same isolators are used when the chiller is supplied with the optional copper finned condenser coils. The spring is fully compressed at approximately 3900 lbs (1769 kgs).

IM 548 / Page 11

Table 5. Operating weight loads (300 thru 340)

ALS

UNIT

SIZE

300A

315A

330A

340A

OPERATING WEIGHT LOAD AT ISOLATOR LOCATIONS, LBS (KGS) FOR UNITS WITH ALUMINUM FINNED COILS

OPERATING

WEIGHT

LBS (KGS)

1 2 3 4 5 6 7 8 9 10

1780 (807) 2060 (934) 2530 (1147) 2530 (1147) 2560 (1161) 2560 (1161) 2170 (984) 2170 (984) 1445 (655) 1445 (655) 21250 (9637)

1780 (807) 2060 (934) 2530 (1147) 2530 (1147) 2560 (1161) 2560 (1161) 2170 (984) 2170 (984) 1445 (655) 1445 (655) 21250 (9637)

1780 (807) 2060 (934) 2540 (1152) 2540 (1152) 2570 (1166) 2570 (1166) 2180 (989) 2180 (989) 1450 (658) 1450 (658) 21320 (9669)

1780 (807) 2060 (934) 2540 (1152) 2540 (1152) 2570 (1166) 2570 (1166) 2180 (989) 2180 (989) 1450 (658) 1450 (658) 21320 (9669)

Note: 1. Unit to be supported at (5) isolator mounting locations per side, 10 total, as indicated.

2. Add approximately 370 lbs (168 kgs) at each isolator location for units with optional copper finned condenser coils.

3. Unit to be level in both directions within

1

⁄

8

inch (3 mm) per 10 feet (3 m).

4. See dimensional drawing 073124701 for exact location of isolator support holes in base frame.

Figure 13. Vibration isolator (360 thru 380)

•

1

•

3

•

5

•

7

•

9

•

11

13

2

•

82

4

•

82

6

•

82

8

•

82

10

•

104

Table 6. Vibration isolators (spring)

ALS UNIT SIZE

360A-380A

TYPE

COLOR

OF

STRIPE

MCQUAY PART

NUMBER

CP2-32 White 047792932

RECOMMENDED

MAXIMUM LOAD

LBS (KG)

3000 (1360)

Note: The same isolators are used when the chiller is supplied with the optional copper finned condenser coils. The spring is fully compressed at approximately 3900 lbs (1769 kgs).

12

•

14

Table 7. Weights (360 thru 380)

ALS

UNIT SIZE

360A

370A

380A

OPERATING WEIGHT

LBS (KGS)

22920

22970

23020

(10394)

(10417)

(10440)

Table 8. Operating weight loads (360 thru 380)

ALS

UNIT

SIZE

OPERATING WEIGHT LOAD AT ISOLATOR LOCATIONS, LBS (KGS) FOR UNITS WITH ALUMINUM FINNED COILS

1 2 3 4 5 6 7 8 9 10 11 12

360A

1780 (807) 2060 (934) 2530 (1147) 2530 (1147) 2540 (1152) 2540 (1152) 1670 (757) 1670 (757) 1720 (780) 1720 (780) 1080 (490) 1080 (490)

370A

1780 (807) 2060 (934) 2540 (1152) 2540 (1152) 2550 (1156) 2550 (1156) 1675 (760) 1675 (760) 1720 (780) 1720 (780) 1080 (490) 1080 (490)

380A

1780 (807) 2060 (934) 2550 (1156) 2550 (1156) 2560 (1161) 2560 (1161) 1680 (762) 1680 (762) 1720 (780) 1720 (780) 1080 (490) 1080 (490)

Note: 1. Unit to be supported at (6) isolator mounting locations per side, 12 total, as indicated.

2. Add approximately 370 lbs (168 kgs) at each isolator location for units with optional copper finned condenser coils.

3. Unit to be level in both directions within

1

⁄

8

inch (3 mm) per 10 feet (3 m).

4. See dimensional drawing 073124801 for exact location of isolator support holes in base frame.

Page 12 / IM 548

Water Piping

Due to the variety of piping practices, it is advisable to follow the recommendations of local authorities.

They can supply the installer with the proper building and safety codes required for a safe and proper installation.

Basically, the piping should be designed with a minimum number of bends and changes in elevation to keep system cost down and performance up. It should contain:

1. Vibration eliminators to reduce vibration and noise transmission to the building.

2. Shutoff valves to isolate the unit from the piping system during unit servicing.

3. Manual or automatic air vent valves at the high points of the system. Drains at the low parts in the system.

4. Some means of maintaining adequate system water pressure (e.g., expansion tank or regulating valve).

5. Temperature and pressure indicators located at the unit to aid in unit servicing.

6. A strainer or some means of removing foreign matter from the water before it enters the pump. It should be placed far enough upstream to prevent cavitation at the pump inlet (consult pump

manufacturer for recommendations). The use of a strainer will prolong pump life and thus keep system performance up.

7. A strainer should also be placed in the supply water line just prior to the inlet of the evaporator.

This will aid in preventing foreign material from entering and decreasing the performance of the evaporator.

8. The shell-and-tube cooler has a thermostat and heating cable to prevent freeze-up, due to low ambient, down to -20°F (-28.8°C). It is suggested that the heating cable be wired to a separate 110V supply circuit. As shipped from the factory, it is factory wired to the control circuit. Any water piping to the unit must also be protected to prevent freezing.

9. If the unit is used as a replacement chiller on a previously existing piping system, the system should be thoroughly flushed prior to unit installation and then regular chilled water analysis and chemical water treatment is recommended immediately at equipment start-up.

10. The total water quantity in the system should be sufficient to prevent frequent “on-off” cycling. A reasonable minimum quantity would allow for a complete water system turnover in not less than 15 minutes.

11. In the event glycol is added to the water system, as an afterthought for freeze protection, recognize that the refrigerant suction pressure will be lower, cooling performance less, and water side pressure drop greater. If the percentage of glycol is large, or if propylene is employed in lieu of ethylene glycol, the added pressure drop and loss of performance could be substantial.

12. For operations requiring the ice mode feature, logic in MicroTech will adjust the freezestat to a pressure equivalent to 13.5°F (7.5°C) below the leaving evaporator water temperature. However, if a different freezestat pressure value is desired, the freezestat can be manually changed through

MicroTech. Refer to IM549 for additional information.

If a separate disconnect is used for the 110V supply to the cooler heating cable, it should be clearly marked so that it is not accidentally shut off during cold seasons.

Prior to insulating the piping and filling the system, a preliminary leak check should be made.

Piping insulation should include a vapor barrier to prevent moisture condensation and possible damage to the building structure. It is important to have the vapor barrier on the outside of the insulation to prevent condensation within the insulation on the cold surface of the pipe.

IM 548 / Page 13

Page 14 / IM 548

Figure 14. Typical field water piping

Vent

Outlet

Inlet

Refrigerant

Connections this end

Vibration

Eliminator

Water

Strainer

Gate

Valve

Drain

Valved

Pressure

Gauge

Vibration

Eliminator

Flow

Switch

Balancing

Valve

Gate

Valve

Flow Switch

A water flow switch must be mounted in either the entering or leaving water line to insure that there will be adequate water flow to the evaporator before the unit can start. This will safeguard against slugging the compressors on start-up. It also serves to shut down the unit in the event that water flow is interrupted to guard against evaporator freeze-up.

A flow switch is available from McQuay under ordering number 0017503300. It is a “paddle” type switch and adaptable to any pipe size from 1" (25mm) to 8" (203mm) nominal. Certain minimum flow rates are required to close the switch and are listed in Table 9. Installation should be as shown in Figure 15.

Electrical connections in the unit control center should be made at terminals 62 and 63. The normally open contacts of the flow switch should be wired between these two terminals. Flow switch contact quality must be suitable for 24 VAC, low current (16ma). Flow switch wire must be in separate conduit from any high voltage conductors (115 VAC and higher).

Table 9. Flow switch minimum flow rates

NOMINAL PIPE SIZE

INCHES (MM)

5 (127)

6 (152)

8 (203)

MINIMUM REQUIRED FLOW TO

ACTIVATE SWITCH - GPM (LPS)

58.7 (3.7)

79.2 (5.0)

140 (8.8)

Note: Water pressure differential switches are not recommended for outdoor applications.

Figure 15. Flow switch

Flow

Flow direction marked on switch

1.00" NPT flow switch connection

Tee

5" pipe dia.– minimum after switch

5" pipe dia.– minimum before switch

Water Connections

Water piping to the cooler can be brought up through the bottom of the unit or through the side between the vertical supports. The dimensional data on pages 20-23 gives the necessary dimensions and locations for all piping connections.

Note: On unit size 175A thru 204A there is a diagonal brace off of a vertical support which will

interfere with the water connection if brought in from the side. This brace can be removed, but only after the unit is in place.

Refrigerant Charge

All units are designed for use with HCFC-22 and are compatible with HCFC alternatives and are shipped with a full operating charge. The operating charge for each unit is shown in the Physical Data

Tables on pages 17-20.

Glycol Solutions

The system glycol capacity, glycol solution flow rate, and pressure drop through the cooler may be calculated using the following formulas and tables.

Note: The procedure below does not specify the type of glycol. Use the derate factors found in Table 10

for corrections when using Ethylene glycol and those in Table 11 for Propylene glycol.

1. Capacity — Cooling capacity is reduced from that with plain water. To find the reduced value multiply the chiller’s water system tonnage by the capacity correction factor to find the chiller’s capacity in the glycol system.

2. Flow — To determine flow (or delta-T) knowing delta-T

(or flow) and cap:

Glycol flow = 24 x cap (glycol) x flow factor delta-T

3. Pressure drop — To determine pressure drop through the cooler, when using glycol, enter the water pressure drop graph on page 13 at the actual glycol flow. Multiply the water pressure drop found there by the PD factor to obtain corrected glycol pressure drop.

4. To determine glycol system kW, multiply the water system kW by factor called Power.

Test coolant with a clean, accurate glycol solution hydrometer (similar to that found in service stations) to determine the freezing point. Obtain percent glycol from the freezing point table below. On glycol applications it is normally recommended by the supplier that a minimum of 25% solution by weight be used for protection against corrosion.

Do not use an automotive grade antifreeze. Industrial grade glycols must be used. Automotive antifreeze contains inhibitors which will cause plating on the copper tubes within the chiller evaporator. The type and handling of glycol used must be consistent with local codes.

Table 10. Ethylene glycol

%

P.G.

10

20

30

40

50

FREEZE PT.

°F

26

18

7

–7

–28

°C

-3

-8

-14

-22

-33

CAP

0.991

0.982

0.972

0.961

0.946

POWER

0.996

0.992

0.986

0.976

0.966

FLOW

1.013

1.040

1.074

1.121

1.178

PD

1.070

1.129

1.181

1.263

1.308

IM 548 / Page 15

Page 16 / IM 548

Table 11. Propylene glycol

%

P.G.

10

20

30

40

50

FREEZE PT.

°F °C

26

19

9

–5

–27

-3

-7

-13

-21

-33

CAP

0.987

0.975

0.962

0.946

0.929

POWER

0.992

0.985

0.978

0.971

0.965

FLOW

1.010

1.028

1.050

1.078

1.116

PD

1.068

1.147

1.248

1.366

1.481

Evaporator Water Flow and Pressure Drop

Balance the chilled water flow through the evaporator. The flow rates must fall between the minimum and maximum values shown in Table 12. Flow rates below the minimum values shown will result in laminar flow which will reduce efficiency, cause erratic operation of the electronic expansion valve and could cause low temperature cutouts. On the other hand flow rates exceeding the maximum values shown can cause erosion on the evaporator water connections and tubes.

Measure the chilled water pressure drop through the evaporator at field installed pressure taps. It is important not to include valves or strainers in these readings.

Variable chilled water flow through the evaporator while the compressor(s) are operating is not recommended. MicroTech control set points are based upon a constant flow and variable temperature.

Table 12. Min/max evaporator flow rates

ALS UNIT

SIZE

205

220

235

250

265

280

300

315

330

340

360

370

380

125

140

155

170

175

185

195

204

MIN. FLOW RATE

GPM LPS

309

335

356

376

391

408

440

459

479

493

523

540

559

186

209

231

253

256

274

284

303

19.5

21.2

22.5

23.8

24.7

25.8

27.8

29.0

30.2

31.1

33.0

34.1

35.3

11.8

13.2

14.6

16.0

16.2

17.3

18.0

19.1

MAX. FLOW RATE

GPM LPS

825

893

950

1000

1043

1088

1173

1222

1276

1313

1395

1438

1490

497

557

617

675

683

730

767

808

52.1

56.4

60.0

63.2

66.0

68.8

74.1

77.1

80.6

82.9

88.1

90.8

94.1

31.4

35.2

39.0

42.7

43.2

46.1

48.5

51.0

Figure 16. Evaporator water pressure drop

10 15 20 25 30

Flow (LPS)

40 50 60 90

10

9

8

7

6

5

4

3

50

40

30

25

20

15

204, 250, 265, 280

195

125

140, 155, 170, 175, 185

300, 315

30

27

24

21

18

15

12

9

150

120

90

75

60

45

100 200 300 400 500 600 800 1000

Flow (GPM)

1500

Physical Data

Table 13. Unit sizes 70 thru 100

ALS MODEL NUMBER

DATA

070A 080A

BASIC DATA

Unit Capacity @ ARI Conditions, tons

Unit Operating Charge R-22, lbs.

68.7

150

81.9

160

Cabinet Dimensions, L x W x H, in.

Unit Operating Weight, lbs.

Unit Shipping Weight, lbs.

124.5 x 83.4 x 93.3

5725

5500

124.5 x 83.4 x 93.3

6175

5900

COMPRESSORS, SCREW, SEMI-HERMETIC

Nominal Capacity, tons 65 80

CONDENSERS, HIGH EFFICIENCY FIN & TUBE TYPE WITH INTEGRAL SUBCOOLER

Coil Face Area, ft.

2

Finned Height x Finned Length, in.

Fins Per Inch x Rows Deep

115.6

160 x 104

16 x 3

CONDENSER FANS, DIRECT DRIVE PROPELLER TYPE

No. of Fans — Fan Diameter, in.

6 - 28

No. of Motors — hp 6 - 1.5

Fan & Motor RPM

Fan Tip Speed, fpm

Total Unit Airflow, ft 3 /sec

1140

8357

54120

EVAPORATOR, DIRECT EXPANSION, BAFFLED SHELL & THRU TUBE

Shell Diameter — Tube Length (in. - ft.) 12 - 08

Water Volume, gallons 24.3

Max. Water Pressure, psi

Max. Refrigerant Pressure, psi

175

225

115.6

161 x 104

16 x 3

6 - 28

6 - 1.5

1140

8357

54120

14 - 08

32.6

175

225

090A

93.2

180

159.1 x 83.4 x 93.3

6825

6500

95

154.1

160 x 138.7

16 x 3

8 - 28

8 - 1.5

1140

8357

72160

14 - 10

41.3

175

225

100A

98.7

190

159.1 x 83.4 x 93.3

7300

6900

95

154.1

160 x 138.7

16 x 3

8 - 28

8 - 1.5

1140

8357

72160

16 - 10

43.6

175

225

IM 548 / Page 17

Table 14. Unit sizes 125 thru 170

ALS MODEL NUMBER

BASIC DATA

DATA

Cabinet dimensions L x W x H, in. (mm)

CKT. 1

Unit capacity @ ARI conditions, tons (kW) 62.2 (218)

Unit operating charge R-22, lbs. (kg) 140 (63.5)

125A

CKT. 2

62.2 (218)

140 (63.5)

228.7 x 83.4 x 92.5

(5809 x 2118 x 2350)

CKT. 1

140A

CKT. 2

64.4 (226)

140 (63.5)

75 (263)

150 (68.1)

228.7 x 83.4 x 92.5

(5809 x 2118 x 2350)

CKT. 1

155A

CKT. 2 CKT. 1

170A

CKT. 2

Unit operating weight, lbs. (kg)

Unit shipping weight, lbs. (kg)

COMPRESSORS, SCREW, SEMI-HERMETIC

9920 (4500)

9600 (4355)

10350 (4700)

9900 (4490)

10670 (4840)

10250 (4650)

10750 (4880)

10350 (4700)

Nominal tons, (kW) 65 (230) 65 (230) 65 (230) 80 (280)

CONDENSERS, HIGH EFFICIENCY FIN & TUBE TYPE WITH INTEGRAL SUBCOOLER

Coil face area, sq. ft. (m 2 )

Finned height x finned length, in. (mm)

80 (280) 80 (280) 80 (280) 95 (335)

115.6 (10.7) 115.6 (10.7) 115.6 (10.7) 115.6 (10.7) 115.6 (10.7) 115.6 (10.7) 115.6 (10.7) 115.6 (10.7)

80 x 208 80 x 208 80 x 208 80 x 208 80 x 208 80 x 208 80 x 208 80 x 208

(2032 x 5283) (2032 x 5283) (2032 x 5283) (2032 x 5283) (2032 x 5283) (2032 x 5283) (2032 x 5283) (2032 x 5283)

Fins per inch x rows deep 16 x 3 16 x 3

CONDENSER FANS, DIRECT DRIVE PROPELLER TYPE

No. of fans – fan diameter, in. (mm)

No. of motors – hp (kW)

Fan & motor rpm, 60

10 – 28 (711)

10 – 1.5 (1.1)

1140

16 x 3

60 Hz fan tip speed, fpm 8357

60 Hz total unit airflow, cfm 90200

EVAPORATOR, DIRECT EXPANSION, BAFFLED SHELL & THRU TUBE

8357

90200

16 x 3

10 – 28 (711)

10 – 1.5 (1.1)

1140

77.1 (271)

150 (68.1)

77.1 (271)

150 (68.1)

228.7 x 83.4 x 92.5

(5809 x 2118 x 2350)

16 x 3 16 x 3

12 – 28 (711)

12 – 1.5 (1.1)

1140

8357

108240

79 (278)

150 (68.1)

89.7 (315)

160 (72.6)

228.7 x 83.4 x 92.5

(5809 x 2118 x 2350)

16 x 3

12 – 28 (711)

12 – 1.5 (1.1)

1140

8357

108240

16 x 3

Shell diameter – tube length

in. (mm) – ft. (mm)

Water volume, gallons (L)

Max. water pressure, psi (kPa)

Max. refrigerant pressure, psi (kPa)

14 – 10

(356 – 3048)

36.1 (136.7)

175 (1207)

225 (1552)

16 – 10

(406 – 3048)

45.6 (172.6)

175 (1207)

225 (1552)

16 – 10

(406 – 3048)

43.6 (165.0)

175 (1207)

225 (1552)

16 – 10

(406 – 3048)

43.6 (165.0)

175 (1207)

225 (1552)

Table 15. Unit sizes 175 thru 204

ALS MODEL NUMBER

DATA 175A 185A 195A 204A

CKT. 1 CKT. 2 CKT. 1 CKT. 2 CKT. 1 CKT. 2 CKT. 1 CKT. 2

BASIC DATA

Unit capacity @ ARI conditions, tons (kW)

Unit operating charge R-22, lbs. (kg)

Cabinet dimensions

L x W x H, in. (mm)

80.4 (282)

160 (72.6)

90.6 (318)

160 (72.6)

263.4 x 83.4 x 92.5

(6690 x 2118 x 2350)

91.2 (320)

160 (72.6)

91.2 (320)

160 (72.6)

263.4 x 83.4 x 92.5

(6690 x 2118 x 2350)

Unit operating weight, lbs. (kg)

Unit shipping weight, lbs. (kg)

COMPRESSORS, SCREW, SEMI-HERMETIC

11250 (5100)

10850 (4920)

11250 (5100)

10850 (4920)

11500 (5218)

11100 (5036)

12570 (5701)

11980 (5433)

Nominal tons, (kW) 80 (280) 95 (335) 95 (335) 95 (335)

CONDENSERS, HIGH EFFICIENCY FIN & TUBE TYPE WITH INTEGRAL SUBCOOLER

Coil face area, sq. ft. (m 2 )

Finned height x finned length, in. (mm)

95 (335) 95 (335) 95 (335) 95 (335)

135.0 (12.5) 135.0 (12.5) 135.0 (12.5) 135.0 (12.5) 135.0 (12.5) 135.0 (12.5) 135.0 (12.5) 135.0 (12.5)

80 x 243 80 x 243 80 x 243 80 x 243 80 x 243 80 x 243 80 x 243 80 x 243

(2032 x 6172) (2032 x 6172) (2032 x 6172) (2032 x 6172) (2032 x 6172) (2032 x 6172) (2032 x 6172) (2032 x 6172)

Fins per inch x rows deep 16 x 3 16 x 3

CONDENSER FANS, DIRECT DRIVE PROPELLER TYPE

No. of fans – fan diameter, in. (mm)

No. of motors – hp (kW)

Fan & motor rpm, 60

14 – 28 (711)

14 – 1.5 (1.1)

1140

16 x 3

60 Hz fan tip speed, fpm 8357

60 Hz total unit airflow, cfm 126280

EVAPORATOR, DIRECT EXPANSION, BAFFLED SHELL & THRU TUBE

8357

126280

16 x 3

14 – 28 (711)

14 – 1.5 (1.1)

1140

94.6 (332)

170 (77.1)

94.6 (332)

170 (77.1)

263.4 x 83.4 x 92.5

(6690 x 2118 x 2350)

16 x 3 16 x 3

14 – 28 (711)

14 – 1.5 (1.1)

1140

8357

126280

101 (355)

195 (88.4)

101 (355)

195 (88.4)

263.4 x 83.4 x 92.5

(6690 x 2118 x 2350)

12 x 4

14 – 28 (711)

14 – 2.0 (1.5)

1140

8357

138908

12 x 4

Shell diameter – tube length

in. (mm) – ft. (mm)

Water volume, gallons (L)

Max. water pressure, psi (kPa)

Max. refrigerant pressure, psi (kPa)

16 – 10

(406 –3048)

43.6 (165.0)

175 (1207)

225 (1552)

16 – 10

(406 – 3048)

43.6 (165.0)

175 (1207)

225 (1552)

18 – 10

(457 – 3048)

57.3 (216.9)

175 (1207)

225 (1552)

20 – 10

(508 – 3048)

69.6 (263.5)

175 (1207)

225 (1552)

Page 18 / IM 548

Table 16. Unit sizes 205 thru 235

DATA

CKT. 1

205A

CKT. 2 CKT. 3

BASIC DATA

Unit capacity @ ARI conditions, tons (kW) 64.4 (226)

Unit operating charge R-22, lbs. (kg) 140 (63.5)

Cabinet dimensions

L x W x H, in. (mm)

66.1 (232)

140 (63.5)

355 x 83.4 x 94.5

(9017 x 2118 x 2400)

75.8 (266)

150 (68.1)

ALS MODEL NUMBER

CKT. 1

220A

CKT. 2 CKT. 3

66.1 (232)

140 (63.5)

78.2 (275)

150 (68.1)

355 x 83.4 x 94.5

(9017 x 2118 x 2400)

79.0 (277)

150 (68.1)

CKT. 1

235A

CKT. 2 CKT. 3

79.3 (279)

150 (68.1)

79.3 (279)

150 (68.1)

355 x 83.4 x 94.5

(9017 x 2118 x 2400)

79.0 (277)

150 (68.1)

Unit operating weight, lbs. (kg)

Unit shipping weight, lbs. (kg)

COMPRESSORS, SCREW, SEMI-HERMETIC

15930 (7224)

15250 (6916)

Nominal tons, (kW) 65 (230) 65 (230) 80 (280) 65 (230)

CONDENSERS, HIGH EFFICIENCY FIN & TUBE TYPE WITH INTEGRAL SUBCOOLER

15980 (7247)

15330 (6952)

80 (280) 80 (280) 80 (280)

16180 (7338)

15530 (7043)

80 (280) 80 (280)

Coil face area, sq. ft. (m 2 )

Finned height x finned length, in. (mm)

Fins per inch x rows deep

115.6 (10.7) 115.6 (10.7) 115.6 (10.7) 115.6 (10.7) 115.6 (10.7) 115.6 (10.7) 115.6 (10.7) 115.6 (10.7) 115.6 (10.7)

80 x 208 80 x 208 160 x 104 80 x 208 80 x 208 160 x 104 80 x 208 80 x 208 160 x 104

(2032 x 5283) (2032 x 5283) (4064 x 2642) (2032 x 5283) (2032 x 5283) (4064 x 2642) (2032 x 5283) (2032 x 5283) (4064 x 2642)

16 x 3 16 x 3

CONDENSER FANS, DIRECT DRIVE PROPELLER TYPE

16 x 3 16 x 3 16 x 3 16 x 3 16 x 3 16 x 3 16 x 3

No. of fans – fan diameter, in. (mm)

No. of motors – hp (kW)

Fan & motor rpm, 60

60 Hz fan tip speed, fpm

60 Hz total unit airflow, cfm

16 – 28 (711)

16 – 1.5 (1.1)

1140

8357

144320

EVAPORATOR, DIRECT EXPANSION, BAFFLED SHELL & THRU TUBE

16 – 28 (711)

16 – 1.5 (1.1)

1140

8357

144320

18 – 28 (711)

18 – 1.5 (1.1)

1140

8357

162360

Shell diameter – tube length

in. (mm) – ft. (mm)

Water volume, gallons (L)

Max. water pressure, psi (kPa)

Max. refrigerant pressure, psi (kPa)

20 – 10

(508 – 3048)

81 (306.6)

175 (1207)

225 (1552)

20 – 10

(508 – 3048)

76 (287.7)

175 (1207)

225 (1552)

20 – 10

(508 – 3048)

76 (287.7)

175 (1207)

225 (1552)

Table 17. Unit sizes 250 thru 280

BASIC DATA

DATA

Unit capacity @ ARI conditions, tons (kW)

Unit operating charge R-22, lbs. (kg)

CKT. 1

80.2 (282)

150 (68.1)

250A

CKT. 2

79.0 (277)

150 (68.1)

CKT. 3

91 (320)

160 (72.6)

ALS MODEL NUMBER

CKT. 1

80.2 (282)

150 (68.1)

265A

CKT. 2

89.7 (315)

160 (72.6)

CKT. 3

91 (320)

160 (72.6)

CKT. 1

91.4 (321)

160 (72.6)

280A

CKT. 2

89.7 (315)

160 (72.6)

CKT. 3

91 (320)

160 (72.6)

Cabinet dimensions

L x W x H, in. (mm)

Unit operating weight, lbs. (kg)

Unit shipping weight, lbs. (kg)

COMPRESSORS, SCREW, SEMI-HERMETIC

355 x 83.4 x 94.5

(9017 x 2118 x 2400)

16200 (7347)

15600 (7075)

355 x 83.4 x 94.5

(9017 x 2118 x 2400)

16200 (7347)

15600 (7075)

355 x 83.4 x 94.5

(9017 x 2118 x 2400)

16250 (7370)

15650 (7098)

Nominal tons, (kW) 80 (280) 80 (280) 95 (335) 80 (280)

CONDENSERS, HIGH EFFICIENCY FIN & TUBE TYPE WITH INTEGRAL SUBCOOLER

Coil face area, sq. ft. (m 2 )

95 (335) 95 (335) 95 (335) 95 (335) 95 (335)

115.6 (10.7) 115.6 (10.7) 115.6 (10.7) 115.6 (10.7) 115.6 (10.7) 115.6 (10.7) 115.6 (10.7) 115.6 (10.7) 115.6 (10.7)

Finned height x finned length, in. (mm)

Fins per inch x rows deep

80 x 208 80 x 208 160 x 104 80 x 208 80 x 208 160 x 104 80 x 208 80 x 208 160 x 104

(2032 x 5283) (2032 x 5283) (4064 x 2642) (2032 x 5283) (2032 x 5283) (4064 x 2642) (2032 x 5283) (2032 x 5283) (4064 x 2642)

16 x 3 16 x 3

CONDENSER FANS, DIRECT DRIVE PROPELLER TYPE

16 x 3 16 x 3 16 x 3 16 x 3 16 x 3 16 x 3 16 x 3

No. of fans – fan diameter, in. (mm)

No. of motors – hp (kW)

Fan & motor rpm, 60

18 – 28 (711)

18 – 1.5 (1.1)

1140

18 – 28 (711)

18 – 1.5 (1.1)

1140

18 – 28 (711)

18 – 1.5 (1.1)

1140

60 Hz fan tip speed, fpm 8357

60 Hz total unit airflow, cfm 162360

EVAPORATOR, DIRECT EXPANSION, BAFFLED SHELL & THRU TUBE

8357

162360

8357

162360

Shell diameter – tube length

in. (mm) – ft. (mm)

Water volume, gallons (L)

Max. water pressure, psi (kPa)

Max. refrigerant pressure, psi (kPa)

20 – 10

(508 – 3048)

69.6 (263.5)

175 (1207)

225 (1552)

20 – 10

(508 – 3048)

69.6 (263.5)

175 (1207)

225 (1552)

20 – 10

(508 – 3048)

69.6 (263.5)

175 (1207)

225 (1552)

IM 548 / Page 19

Table 18. Unit sizes 300 thru 340

ALS MODEL NUMBER

DATA 300A 315A 330A 340A

CKT. 1 CKT. 2 CKT. 3 CKT. 4 CKT. 1 CKT. 2 CKT. 3 CKT. 4 CKT. 1 CKT. 2 CKT. 3 CKT. 4 CKT. 1 CKT. 2 CKT. 3 CKT. 4

BASIC DATA

Unit capacity @ ARI conditions, tons (kW)

66.9 (235) 66.9 (235) 79.7 (280) 79.7 (280) 66.9 (235) 79.2 (278) 79.7 (280) 79.7 (280) 79.2 (278) 79.2 (278) 80.3 (282) 80.3 (282) 79.2 (278) 79.2 (278) 80.3 (282) 89.4 (314)

Unit operating charge R-22, lbs. (kg)

155 (70.3) 155 (70.3) 160 (72.6) 160 (72.6) 155 (70.3) 160 (72.6) 160 (72.6) 160 (72.6) 160 (72.6) 160 (72.6) 160 (72.6) 160 (72.6) 160 (72.6) 160 (72.6) 160 (72.6) 170 (77.1)

Cabinet dimensions

L x W x H, in. (mm)

389.7 x 83.4 x 94.5

(9898 x 2118 x 2400)

389.7 x 83.4 x 94.5

(9898 x 2118 x 2400)

389.7 x 83.4 x 94.5

(9898 x 2118 x 2400)

389.7 x 83.4 x 94.5

(9898 x 2118 x 2400)

Unit operating weight, lbs. (kg)

Unit shipping weight, lbs. (kg)

COMPRESSORS, SCREW, SEMI-HERMETIC

21250 (9637)

20300 (9206)

21250 (9637)

20300 (9206)

21320 (9669)

20400 (9252)

21320 (9669)

20400 (9252)

Nominal tons, (kW) 65 (230) 65 (230) 80 (280) 80 (280) 65 (230) 80 (280) 80 (280) 80 (280) 80 (280) 80 (280) 80 (280) 80 (280) 80 (280) 80 (280) 80 (280) 95 (335)

CONDENSERS, HIGH EFFICIENCY FIN & TUBE TYPE WITH INTEGRAL SUBCOOLER

Coil face area, sq. ft. (m 2 )

96.3 (8.9) 96.3 (8.9) 96.3 (8.9) 96.3 (8.9) 96.3 (8.9) 96.3 (8.9) 96.3 (8.9) 96.3 (8.9) 96.3 (8.9) 96.3 (8.9) 96.3 (8.9) 96.3 (8.9) 96.3 (8.9) 96.3 (8.9) 96.3 (8.9) 96.3 (8.9)

Finned height x finned length, in. (mm)

80 x173 80 x173 80 x173 80 x173 80 x173 80 x173 80 x173 80 x173 80 x173 80 x173 80 x173 80 x173 80 x173 80 x173 80 x173 80 x173

(2032 x 4394) (2032 x 4394) (2032 x 4394) (2032 x 4394) (2032 x 4394) (2032 x 4394) (2032 x 4394) (2032 x 4394) (2032 x 4394) (2032 x 4394) (2032 x 4394) (2032 x 4394) (2032 x 4394) (2032 x 4394) (2032 x 4394) (2032 x 4394)

Fins per inch x rows deep 12 x 4 12 x 4 12 x 4 12 x 4 12 x 4 12 x 4 12 x 4 12 x 4 12 x 4 12 x 4 12 x 4 12 x 4 12 x 4 12 x 4 12 x 4 12 x 4

CONDENSER FANS, DIRECT DRIVE PROPELLER TYPE

No. of fans – fan diameter, in. (mm)

No. of motors – hp (kW)

Fan & motor rpm, 60

20 – 28 (711)

20 – 2.0 (1.5)

1140

20 – 28 (711)

20 – 2.0 (1.5)

1140

20 – 28 (711)

20 – 2.0 (1.5)

1140

20 – 28 (711)

20 – 2.0 (1.5)

1140

60 Hz fan tip speed, fpm

60 Hz total unit airflow, cfm

8357

198440

EVAPORATOR, DIRECT EXPANSION, BAFFLED SHELL & THRU TUBE

8357

198440

8357

198440

8357

198440

Shell diameter – tube length

in. (mm) – ft. (mm)

Water volume, gallons (L)

Max. water pressure, psi (kPa)

Max. refrigerant pressure, psi (kPa)

24 – 10

(609 – 3048)

112 (424)

175 (1207)

225 (1552)

24 – 10

(609 – 3048)

112 (424)

175 (1207)

225 (1552)

24 – 10

(609 – 3048)

107 (405.0)

175 (1207)

225 (1552)

24 – 10

(609 – 3048)

107 (405.0)

175 (1207)

225 (1552)

Table 19. Unit sizes 360 thru 380

DATA 360A

ALS MODEL NUMBER

370A 380A

CKT. 1 CKT. 2 CKT. 3 CKT. 4 CKT. 1 CKT. 2 CKT. 3 CKT. 4 CKT. 1 CKT. 2 CKT. 3 CKT. 4

BASIC DATA

Unit capacity @ ARI conditions, tons (kW)

Unit operating charge R-22, lbs. (kg)

80.9 (284) 80.9 (284) 93.4 (328) 93.4 (328) 80.9 (284) 91.8 (323) 93.4 (328) 93.4 (328) 92.3 (325) 92.3 (325) 93.9 (330) 93.9 (330)

175 (79.4) 175 (79.4) 180 (81.6) 180 (81.6) 175 (79.4) 180 (81.6) 180 (81.6) 180 (81.6) 180 (81.6) 180 (81.6) 180 (81.6) 180 (81.6)

Cabinet dimensions

L x W x H, in. (mm)

459 x 83.4 x 94.5

(11659 x 2118 x 2400)

Unit operating weight, lbs. (kg)

Unit shipping weight, lbs. (kg)

22920 (10395)

22000 (9977)

COMPRESSORS, SCREW, SEMI-HERMETIC

459 x 83.4 x 94.5

(11659 x 2118 x 2400)

22970 (10417)

22050 (10000)

459 x 83.4 x 94.5

(11659 x 2118 x 2400)

23020 (10440)

22100 (10023)

Nominal tons, (kW) 80 (280) 80 (280) 95 (335) 95 (335) 80 (280) 95 (335) 95 (335) 95 (335) 95 (335) 95 (335) 95 (335) 95 (335)

CONDENSERS, HIGH EFFICIENCY FIN & TUBE TYPE WITH INTEGRAL SUBCOOLER

Coil face area, sq. ft. (m 2 )

115.6 (10.7) 115.6 (10.7) 115.6 (10.7) 115.6 (10.7) 115.6 (10.7) 115.6 (10.7) 115.6 (10.7) 115.6 (10.7) 115.6 (10.7) 115.6 (10.7) 115.6 (10.7) 115.6 (10.7)

Finned height x finned length, in. (mm)

80 x 208 80 x 208 80 x 208 80 x 208 80 x 208 80 x 208 80 x 208 80 x 208 80 x 208 80 x 208 80 x 208 80 x 208

(2032 x 5283) (2032 x 5283) (2032 x 5283) (2032 x 5283) (2032 x 5283) (2032 x 5283) (2032 x 5283) (2032 x 5283) (2032 x 5283) (2032 x 5283) (2032 x 5283) (2032 x 5283)

Fins per inch x rows deep 12 x 4 12 x 4 12 x 4 12 x 4 12 x 4 12 x 4 12 x 4 12 x 4 12 x 4 12 x 4 12 x 4 12 x 4

CONDENSER FANS, DIRECT DRIVE PROPELLER TYPE

No. of fans– fan diameter, in. (mm)

No. of motors – hp (kW)

Fan & motor rpm, 60

24 – 28 (711)

24 – 2.0 (1.5)

1140

24 – 28 (711)

24 – 2.0 (1.5)

1140

24 – 28 (711)

24 – 2.0 (1.5)

1140

60 Hz fan tip speed, fpm 8357

60 Hz total unit airflow, cfm 238128

EVAPORATOR, DIRECT EXPANSION, BAFFLED SHELL & THRU TUBE

8357

238128

8357

238128

Shell diameter – tube length

in. (mm) – ft. (mm)

Water volume, gallons (L)

Max. water pressure, psi (kPa)

Max. refrigerant pressure, psi (kPa)

24 – 10

(609 – 3048)

107 (405.0)

175 (1207)

225 (1552)

24 – 10

(609 – 3048)

107 (405.0)

175 (1207)

225 (1552)

24 – 10

(609 – 3048)

107 (405.0)

175 (1207)

225 (1552)

Page 20 / IM 548

Major Components

205A

220A

235A

250A

265A

280A

300A

315A

125A

140A

155A

170A

175A

185A

195A

204A

330A

340A

360A

370A

380A

Table 20. Unit sizes 125 thru 380

UNIT SIZE

155

155

167

167

167

175

155

155

167

167

167

167

175

155

155

167

167

167

175

175

175

COMPRESSOR

IDENTIFICATION

155

167

167

167

175

175

155

167

167

167

167

175

175

155

167

167

175

175

175

175

175

167

167

167

167

175

175

167

167

167

167

175

175

175

—

—

—

—

—

—

—

—

—

—

167

167

—

—

—

—

167

175

175

175

175

—

—

—

—

—

—

—

—

EVAPORATOR

VESSEL SIZE

2010-3

2010-2

2010-2

2010-1

2010-1

2010-1

2410-2

2410-2

1410-1

1610-1

1610-1

1610-1

1610-1

1610-1

1810-1

2010-1

2410-1

2410-1

2410-1

2410-1

2410-1

Compressor Staging Sequence

Two compressors available (125 thru 204)

Table 21. Staging up

STAGE

7

8

5

6

3

4

1

2

LEAD LAG 1

COMPRESSOR COMPRESSOR

—

50%

75%

50%

75%

75%

100%

100%

—

0%

0%

50%

50%

75%

75%

100%

UNIT

CAPACITY

0%

25.0%

37.5%

50.0%

62.5%

75.0%

87.5%

100.0%

140

140

140

140

170

170

140

140

140

140

140

170

170

100

140

140

170

170

170

170

170

140

140

140

140

170

170

140

140

140

140

140

170

170

100

140

140

170

170

170

170

170

ELECTRONIC EXPANSION

VALVE SIZE

140

140

140

140

170

170

140

140

140

170

170

170

170

—

—

—

—

—

—

—

—

—

—

140

140

—

—

—

—

140

170

170

170

170

—

—

—

—

—

—

—

—

M2-M6

M2-M6

M2-M6

M2-M6

M2-M6

M2-M6

M2-M6

M2-M6

M2-M6

M2-M6

M2-M6

M2-M6

M2-M6

M2-M6

M2-M6

M2-M6

M2-M6

M2-M6

M2-M6

M2-M6

M2-M6

CONTACTOR DESIGNATION

FOR COMPRESSOR

M1-M5

M1-M5

M1-M5

M1-M5

M1-M5

M1-M5

M1-M5

M1-M5

M1-M5

M1-M5

M1-M5

M1-M5

M1-M5

M1-M5

M1-M5

M1-M5

M1-M5

M1-M5

M1-M5

M1-M5

M1-M5

M3-M7

M3-M7

M3-M7

M3-M7

M3-M7

M3-M7

M3-M7

M3-M7

—

—

—

—

—

—

—

—

M3-M7

M3-M7

M3-M7

M3-M7

M3-M7

—

—

—

—

—

—

M4-M8

M4-M8

—

—

—

—

—

—

—

—

M4-M8

M4-M8

M4-M8

M4-M8

M4-M8

Table 22. Staging down

STAGE

7

8

5

6

3

4

1

2

LEAD LAG 1

COMPRESSOR COMPRESSOR

25%

50%

75%

50%

75%

75%

100%

100%

0%

0%

0%

50%

50%

75%

75%

100%

UNIT

CAPACITY

12.5%

25.0%

37.5%

50.0%

62.5%

75.0%

87.5%

100.0%

One compressor available

Table 23. Staging up

STAGE

3

4

1

2

LEAD LAG 1

COMPRESSOR COMPRESSOR

—

50%

75%

50%

—

0%

0%

0%

UNIT

CAPACITY

0%

25.0%

37.5%

50.0%

Table 24. Staging down

STAGE

3

4

1

2

LEAD LAG 1

COMPRESSOR COMPRESSOR

25%

50%

75%

100%

0%

0%

0%

0%

UNIT

CAPACITY

12.5%

25.0%

37.5%

50.0%

Three compressors available (205 thru 280)

Table 25. Staging up

7

8

5

6

3

4

1

2

9

10

11

12

STAGE

LEAD LAG 1 LAG 2 UNIT

COMPRESSOR COMPRESSOR COMPRESSOR CAPACITY

—

50%

75%

50%

75%

75%

75%

75%

75%

100%

100%

100%

—

0%

0%

50%

50%

75%

50%

75%

75%

75%

100%

100%

—

0%

0%

0%

0%

0%

50%

50%

75%

75%

75%

100%

0%

16.7%

25.0%

33.3%

41.7%

50.0%

58.3%

66.7%

75.0%

83.3%

91.6%

100.0%

Table 26. Staging down

7

8

5

6

3

4

1

2

9

10

11

12

STAGE

LEAD LAG 1 LAG 2 UNIT

COMPRESSOR COMPRESSOR COMPRESSOR CAPACITY

25%

50%

75%

50%

75%

50%

75%

75%

75%

100%

100%

100%

0%

0%

0%

50%

50%

50%

50%

75%

75%

75%

100%

100%

0%

0%

0%

0%

0%

50%

50%

50%

75%

75%

75%

100%

8.3%

16.7%

25.0%

33.3%

41.7%

50.0%

58.3%

66.7%

75.0%

83.3%

91.6%

100.0%

IM 548 / Page 21

Two compressors available

Table 27. Staging up

7

8

5

6

3

4

1

2

STAGE

LEAD LAG 1 LAG 2 UNIT

COMPRESSOR COMPRESSOR COMPRESSOR CAPACITY

—

50%

75%

50%

75%

75%

100%

100%

—

0%

0%

50%

50%

75%

75%

100%

—

0%

0%

0%

0%

0%

0%

0%

0%

16.7%

25.0%

33.3%

41.7%

50.0%

58.3%

66.7%

Table 28. Staging down

7

8

5

6

3

4

1

2

STAGE

LEAD LAG 1 LAG 2 UNIT

COMPRESSOR COMPRESSOR COMPRESSOR CAPACITY

25%

50%

75%

50%

75%

75%

100%

100%

0%

0%

0%

50%

50%

75%

75%

100%

0%

0%

0%

0%

0%

0%

0%

0%

8.3%

16.7%

25.0%

33.3%

41.7%

50.0%

58.3%

66.7%

One compressor available

Table 29. Staging up

STAGE

LEAD LAG 1 LAG 2 UNIT

COMPRESSOR COMPRESSOR COMPRESSOR CAPACITY

3

4

1

2

—

50%

75%

100%

—

0%

0%

0%

—

0%

0%

0%

0%

16.7%

25.0%

33.3%

Table 30. Staging down

STAGE

1

2

3

4

LEAD LAG 1 LAG 2 UNIT

COMPRESSOR COMPRESSOR COMPRESSOR CAPACITY

25%

50%

75%

100%

0%

0%

0%

0%

0%

0%

0%

0%

8.3%

16.7%

25.0%

33.3%

Four compressors available (300 thru 380)

Table 31. Staging up

10

11

12

13

14

15

16

7

8

9

5

6

3

4

1

2

STAGE

LEAD LAG 1 LAG 2 LAG 3 UNIT

COMPRESSOR COMPRESSOR COMPRESSOR COMPRESSOR CAPACITY

75%

75%

75%

100%

100%

100%

100%

—

50%

75%

50%

75%

75%

75%

75%

75%

—

0%

0%

50%

50%

75%

50%

75%

75%

75%

75%

75%

75%

100%

100%

100%

—

0%

0%

0%

0%

0%

50%

50%

75%

50%

75%

75%

75%

75%

100%

100%

—

0%

0%

0%

0%

0%

0%

0%

0%

50%

50%

75%

75%

75%

75%

100%

0.0%

12.5%

18.8%

25.0%

31.3%

37.5%

43.8%

50.0%

56.3%

62.5%

68.8%

75.0%

81.3%

87.5%

93.8%

100.0%

Staging down

LEAD LAG 1 LAG 2 LAG 3 UNIT

COMPRESSOR COMPRESSOR COMPRESSOR COMPRESSOR CAPACITY

75%

75%

75%

100%

100%

100%

100%

25%

50%

75%

50%

75%

50%

75%

50%

75%

0%

0%

0%

50%

50%

50%

50%

50%

50%

75%

75%

75%

75%

100%

100%

100%

0%

0%

0%

0%

0%

50%

50%

50%

50%

50%

75%

75%

75%

75%

100%

100%

0%

0%

0%

0%

0%

0%

0%

50%

50%

50%

50%

75%

75%

75%

75%

100%

6.3%

12.5%

18.8%

25.0%

31.3%

37.5%

43.8%

50.0%

56.3%

62.5%

68.8%

75.0%

81.3%

87.5%

93.8%

100.0%

Three compressors available

Table 32. Staging up

7

8

5

6

3

4

1

2

9

10

11

12

STAGE

LEAD LAG 1 LAG 2 LAG 3 UNIT

COMPRESSOR COMPRESSOR COMPRESSOR COMPRESSOR CAPACITY

—

50%

75%

50%

75%

75%

75%

75%

75%

100%

100%

100%

—

0%

0%

50%

50%

75%

50%

75%

75%

75%

100%

100%

—

0%

0%

0%

0%

0%

50%

50%

75%

75%

75%

100%

—

0%

0%

0%

0%

0%

0%

0%

0%

0%

0%

0%

0.0%

12.5%

18.8%

25.0%

31.3%

37.5%

43.8%

50.0%

56.3%

62.5%

68.8%

75.0%

Staging down

LEAD LAG 1 LAG 2 LAG 3 UNIT

COMPRESSOR COMPRESSOR COMPRESSOR COMPRESSOR CAPACITY

25%

50%

75%

50%

75%

50%

75%

75%

75%

100%

100%

100%

0%

0%

0%

50%

50%

50%

50%

75%

75%

75%

100%

100%

0%

0%

0%

0%

0%

50%

50%

50%

75%

75%

75%

100%

0%

0%

0%

0%

0%

0%

0%

0%

0%

0%

0%

0%

6.3%

12.5%

18.8%

25.0%

31.3%

37.5%

43.8%

50.0%

56.3%

62.5%

68.8%

75.0%

Page 22 / IM 548

Two compressors available

Table 33. Staging up

7

8

5

6

3

4

1

2

STAGE

LEAD LAG 1 LAG 2 LAG 3 UNIT

COMPRESSOR COMPRESSOR COMPRESSOR COMPRESSOR CAPACITY

—

50%

75%

50%

75%

75%

100%

100%

—

0%

0%

50%

50%

75%

75%

100%

—

0%

0%

0%

0%

0%

0%

0%

—

0%

0%

0%

0%

0%

0%

0%

0.0%

12.5%

18.8%

25.0%

31.3%

37.5%

43.8%

50.0%

Staging down

LEAD LAG 1 LAG 2 LAG 3 UNIT

COMPRESSOR COMPRESSOR COMPRESSOR COMPRESSOR CAPACITY

25%

50%

75%

50%

75%

75%

100%

100%

0%

0%

0%

50%

50%

75%

75%

100%

0%

0%

0%

0%

0%

0%

0%

0%

0%

0%

0%

0%

0%

0%

0%

0%

6.3%

12.5%

18.8%

25.0%

31.3%

37.5%

43.8%

50.0%

One compressor available

Table 34. Staging up

STAGE

1

2

3

4

LEAD LAG 1 LAG 2 LAG 3 UNIT

COMPRESSOR COMPRESSOR COMPRESSOR COMPRESSOR CAPACITY

—

50%

75%

100%

—

0%

0%

0%

—

0%

0%

0%

—

0%

0%

0%

0.0%

12.5%

18.8%

25.0%

Staging down

LEAD LAG 1 LAG 2 LAG 3 UNIT

COMPRESSOR COMPRESSOR COMPRESSOR COMPRESSOR CAPACITY

25%

50%

75%

100%

0%

0%

0%

0%

0%

0%

0%

0%

0%

0%

0%

0%

6.3%

12.5%

18.8%

25.0%

IM 548 / Page 23

Dimensional Data

Figure 17. Unit sizes 125 thru 204

Air discharge d

6.0 (152) for ALS125A-195A

8.0 (203) for ALS204A

Victaulic connections furnished with grooves for victaulic couplings by others

Note:

1. All dimensions in inches (mm).

2. All units have (2) independent refrigerant circuits.

3. Remove diagonal brace in way of water outlet at installation for ALS204A only.

Compressor

#1

Inlet

Outlet

Evaporator

2 refrigerant circuits

Compressor

#2

Power entry location this side only.

2 additional knockouts 6.0 (152) above and below this opening for multiple power supply

Optional coil guards

ALS125A

ALS140A

ALS155A

ALS170A

ALS175A

ALS185A

ALS195A

ALS204A

Air discharge d

Control center

Power center

Control wiring entry knockouts for 1 ⁄

2

(13) conduit both sides of unit

2.150 (5464) for ALS125A-170A

249.7 (6345) for ALS175A-204A

Note

#3

Unit mounting holes

2.5 (64) dia. lifting holes (4) located from control center end (both sides)

18.6 (472) to L1 (all units) and 174.6

(4435) to L2 (ALS125A-170A) or 189.9

(4823) (ALS175A-204A).

2.0 (51)

Typ.

spacing for 1.0 (25) diameter isolator mounting hole locations (6)

Table 35. Unit sizes 125 thru 204

ALS

UNIT

SIZE

125A

140A

155A

170A

175A

185A

195A

204A

LENGTH EVAPORATOR

A B C D

228.7 (5809) 117.6 (2987) 13.8 (351)

228.7 (5809) 118.5 (3010) 12.9 (328)

228.7 (5809) 118.5 (3010) 12.9 (328)

228.7 (5809) 118.5 (3010) 12.9 (328)

28.7 (729)

28.7 (729)

28.7 (729)

28.7 (729)

263.4 (6690) 153.2 (3891) 47.6 (1209) 28.7 (729)

263.4 (6690) 153.2 (3891) 47.6 (1209) 28.7 (729)

263.4 (6690) 153.2 (3891) 47.6 (1209) 27.3 (693)

263.4 (6690) 152.2 (3866) 48.5 (1232) 25.7 (653)

UNIT WEIGHTS LBS (KGS)

E

CENTER OF GRAVITY

X Y

STANDARD UNIT

ADDITIONAL WT.

OPERATING SHIPPING FOR COPPER FINS

19.4 (493) 104.3 (2649) 41.7 (1059) 9920 (4500) 9600 (4355)

19.4 (493) 104.3 (2649) 41.7 (1059) 10350 (4700) 9900 (4490)

19.4 (493) 105.2 (2672) 41.7 (1059) 10670 (4840) 10250 (4650)

19.4 (493) 105.2 (2672) 41.7 (1059) 10750 (4880) 10350 (4700)

19.4 (493) 113.1 (2873) 41.7 (1059) 11250 (5100) 10850 (4920)

19.4 (493) 113.1 (2873) 41.7 (1059) 11250 (5100) 10850 (4920)

20.4 (518) 115.2 (2926) 41.7 (1059) 11500 (5218) 11100 (5036)

20.2 (513) 116.5 (2959) 41.7 (1059) 12570 (5701) 11980 (5433)

1652 (750)

1652 (750)

1652 (750)

1652 (750)

1930 (876)

1930 (876)

1930 (876)

2025 (918)

Table 35. Unit sizes 125 thru 204 (continued)

ALS

UNIT

SIZE

125A

140A

155A

170A

175A

185A

195A

204A

COMPRESSOR

QTY.

2

2

2

2

2

2

2

2

NOM. TONS

65 / 65

65 / 80

80 / 80

80 / 95

80 / 95

95 / 95

95 / 95

95 / 95

QTY.

14

14

14

14

10

10

12

12

FANS

H.P.

1.5

1.5

1.5

2.0

1.5

1.5

1.5

1.5

OPERATING REFRIGERANT

CHARGE (R-22) LBS (KGS)

SYSTEM #1

140 (63.5)

140 (63.5)

150 (68.1)

150 (68.1)

160 (72.6)

160 (72.6)

170 (77.1)

195 (88.5)

SYSTEM #2

140 (63.5)

150 (68.1)

150 (68.1)

160 (72.6)

160 (72.6)

160 (72.6)

170 (77.1)

195 (88.5)

Page 24 / IM 548

Figure 18. Unit sizes 205 thru 280

Note:

1. All dimensions in inches (mm).

2. All units have (3) independent refrigerant circuits.

Air discharge

d

8" (203 mm) victaulic connections furnished with grooves for victaulic couplings by others

6.0 (152)

Compressor

#1

Compressor

#2

222.1 (5641)

118.4 (3007)

Inlet Outlet

Evaporator

3 refrigerant circuits

Compressor

#3

Power entry location this side only.

2 additional knockouts 6" (152 mm) above and below this opening for multiple power supply

13.7 (348)

Optional coil guards

Air discharge

d

ALS205A

ALS220A

ALS235A

ALS250A

ALS265A

ALS280A

Control center

Power center

91.2

(2316)

65.6

1666)

94.5

(2400)

83.4

(2118)

10.1

(256)

Control wiring entry knockouts for /

2

" (13 mm) conduit both sides of unit

13.0 (330)

95.0 (2413)

“X”

177.0 (4496)

259.0 (6579)

355.0 (9017)

341.0 (8661)

28.5 (724)

22.0 (559)

8.5 (216)

2.0 (51)

“Y”

2.0 (51 mm) typ. spacing for 1" (25 mm)

Unit mounting holes (10)

2.5" (64 mm) dia.

lifting holes (6) located 18.6" (472 mm),

150.0" (3810 mm) and

293.0" (7442 mm) from control center end (both sides) dia. isolation mounting holes (10)

Table 36. Unit sizes 205 thru 280

ALS

UNIT

SIZE

CENTER OF GRAVITY UNIT WEIGHTS

X Y OPERATING SHIPPING

IN.

MM IN.

MM LBS.

KGS.

LBS.

KGS.

205A 146.7 3,726 41.7 1,059 15,930 7,224 15,250 6,916

220A 146.7 3,726 41.7 1,059 15,980 7,247 15,330 6,952

235A 146.7 3,726 41.7 1,059 16,180 7,338 15,530 7,043

250A 146.7 3,726 41.7 1,059 16,200 7,347 15,600 7,075

265A 146.7 3,726 41.7 1,059 16,200 7,347 15,600 7,075

280A 146.7 3,726 41.7 1,059 16,250 7,370 15,650 7,098

ADDITIONAL WEIGHT FOR

UNITS WITH COPPER FIN COILS

LBS.

2,478

2,478

2,478

2,478

2,478

2,478

KGS.

1,124

1,124

1,124

1,124

1,124

1,124

COMPRESSORS FANS OPERATING REFRIGERANT CHARGE (R-22)

SYSTEM #1 SYSTEM #2 SYSTEM #3

QTY. NOM. TONS QTY.

H.P.

3

3

3

3

3

3

65/65/80

65/80/80

80/80/80

80/80/95

80/95/95

95/95/95

16

16

18

18

18

18

LBS.

KGS.

LBS.

KGS.

LBS.

KGS.

1.5

140 63.5

140 63.5

150 68.1

1.5

140 63.5

150 68.1

150 68.1

1.5

150 68.1

150 68.1

150 68.1

1.5

150 68.1

150 68.1

160 72.6

1.5

150 68.1

160 72.6

160 72.6

1.5

160 72.6

160 72.6

160 72.6

IM 548 / Page 25

Figure 19. Unit sizes 300 thru 340

Note:

1. All dimensions in inches (mm).

2. All units have (4) independent refrigerant circuits.

8.0 (203) victaulic connections furnished with grooves for victaulic couplings by others

Compressor

#1

Compressor

#3

Compressor

#2

Compressor

#4

189.8 (4821)

Inlet

Outlet

Evaporator

4 refrigerant circuits

86.1 (2187)

23.4 (594)

Air

6.0 (152)

Power entry location this side only.

2 additional knockouts 6 (152) above and below this opening for multiple power supply

Optional coil guards

Air

Control center

Power center

94.5

(2400)

91.2

(2316)

65.6

(1666)

83.4

(2118)

10.1

(256)

Control wiring entry knockouts for /

2

(13) conduit both sides of unit

22.0 (559)

13.0 (330)

95.0 (2413)

“X”

177.0 (4496)

259.0 (6579)

375.7 (9543)

389.7 (9898)

2.0

“Y”

2.5 (64) dia. lifting holes (6)

28.5 (724)

8.5 (216)

2.0 (51) typ. spacing for 1.0 (25) diameter isolator/mounting hole locations (10) located 18.6 (472), 167.0 (4242) and 320.0 (8128) from control center end (both sides)

Unit isolator/mounting hole locations (10)

Table 37. Unit sizes 300 thru 340

ALS

UNIT

SIZE

CENTER OF GRAVITY

X Y

UNIT WEIGHTS

OPERATING SHIPPING

IN.

MM IN.

MM LBS.

KGS.

LBS.

KGS.

300A 166.9 4239 41.7 1059 21,250 9637 20,300 9206

315A 166.9 4239 41.7 1059 21,250 9637 20,300 9206

330A 166.9 4239 41.7 1059 21,320 9669 20,400 9252

340A 166.9 4239 41.7 1059 21,320 9669 20,400 9252

ADD’L WEIGHT FOR UNITS COMPRESSORS

WITH COPPER FIN COILS

QTY.

NOM.

LBS.

KGS.

TONS

3,671

3,671

3,671

3,671

1665

1665

1665

1665

4

4

4

4

65/65/80/80

65/80/80/80

80/80/80/80

80/80/80/95

FANS

QTY.

20

20

20

20

HP

OPERATING REFRIGERANT CHARGE (R-22)

SYST. #1 SYST. #2 SYST. #3 SYST. #4

LBS. KGS. LBS. KGS. LBS. KGS. LBS. KGS.

2.0 155

2.0 155

2.0 160

2.0 160

70.3 155

70.3 160

72.6 160

72.6 160

70.3 160

72.6 160

72.6 160

72.6 160

72.6 160

72.6 160

72.6 160

72.6 170

72.6

72.6

72.6

77.1

Page 26 / IM 548

Figure 20. Unit sizes 360 thru 380

Note:

1. All dimensions in inches (mm).

2. All units have (4) independent refrigerant circuits.

3. Remove brace in way of water outlet at installation.

8.0 (203) victaulic connections furnished with grooves for victaulic couplings by others

Inlet Outlet

Evaporator

4 refrigerant circuits

259.2 (6584)

155.5 (3950)

23.4 (594)

Compressor

#1

Compressor

#3

Compressor

#2

Compressor

#4

Air discharge d

6.0 (152)

Control center

Power center

91.2

94.5

(2400)

(2316)

65.6

(1666)

83.4

(2118)

10.1

(256)

Control wiring entry knockouts for 1 /

2

(13) conduit both sides of unit

Power entry location this side only.

2 additional knockouts 6 (152) above and below this opening for multiple power supply

Optional coil guards

Air discharge d

22.0 (559)

13.0 (330)

95.0 (2413)

177.0 (4496)

“X”

259.0 (6579)

341.0 (8661)

445.0 (11303)

459.0 (11659)

Note #3

2.0

“Y”

28.5 (724)

8.5 (216)

2.5 (64) dia. lifting holes (8) located 18.6 (472), 146.6 (3724)

274.6 (6975) and 403.8 (10257) from control center end (both sides)

2.0 (51) typ. spacing for

1.0 (25) diameter isolator/mounting hole locations (12)

Unit isolator/mounting hole locations (12)

Table 38. Unit sizes 360 thru 380

ALS

UNIT

SIZE

CENTER OF GRAVITY

X Y

UNIT WEIGHTS

OPERATING SHIPPING

IN.

MM IN.

MM LBS.

KGS.

LBS.

KGS.

360A 185.0 4699 41.7 1059 22,920 10395 22,000 9977

370A 185.0 4699 41.7 1059 22,970 10417 22,050 10000

380A 185.0 4699 41.7 1059 23,020 10440 22,100 10023

ADD’L WEIGHT FOR UNITS COMPRESSORS

WITH COPPER FIN COILS

QTY.

NOM.

LBS.

KGS.

TONS

4,406

4,406

4,406

1998

1998

1998

4

4

4

80/80/95/95

80/95/95/95

95/95/95/95

FANS

QTY.

24

24

24

HP

OPERATING REFRIGERANT CHARGE (R-22)

SYST. #1 SYST. #2 SYST. #3 SYST. #4

LBS. KGS. LBS. KGS. LBS. KGS. LBS. KGS.

2.0 175

2.0 175

2.0 180

79.4 175

79.4 180

81.6 180

79.4 180 81.6 180

81.6 180 81.6 180

81.6 180 81.6 180

81.6

81.6

81.6

IM 548 / Page 27

Page 28 / IM 548

Field Wiring

General

Wiring must comply with all applicable codes and ordinances. Warranty is voided if wiring is not in accordance with specifications. An open fuse indicates a short, ground, or overload. Before replacing a fuse or restarting a compressor or fan motor, the trouble must be found and corrected.

Copper wire is required for all power lead terminations at the unit and copper must be used for all other wiring to the unit.

ALS units may be ordered with main power wiring for either single or multiple point power connection.

If single point power connection is ordered, a single large power terminal block is provided and wiring within the unit is sized in accordance with the National Electrical Code. A single field supplied disconnect is required. An optional factory mounted transformer for the 115 volt control circuit may be provided.

If multiple point power wiring is ordered, two power connections (125 thru 204) and (300 thru 380) or three power connections (205 thru 280) are required and wiring within the unit is sized in accordance with the National Electrical Code. A separate circuit is required for the 115 volt control circuit. Separate field supplied disconnects are required for each electrical circuit.

It may be desirable to have the unit cooler heater on a separate disconnect switch from the main unit power supply so that the unit may be shut down without defeating the freeze protection provided by the cooler heater.

ALS unit compressors are single direction rotation compressors. For this reason proper phasing of electrical power is important. Electrical phasing must be A, B, C for electrical phases 1, 2 and 3

(A=L1,B=L2,C=L3). Units supplied with single point factory power connections will include one

MotorSaver

®

phase failure, phase reversal protective device that will prevent operation of the unit with incorrect power phasing. The MotorSaver is factory wired and tested. Do not alter the wiring to the

MotorSaver.

Multiple point power wired units will include two (125 thru 204) and (300 thru 380) or three (205 thru

280) MotorSaver safety controls (one for each power supply), and the contractor is cautioned to not apply power until the phasing is verified with a phase sequence meter.

Internal power wiring to the compressors for the single point versus the multiple point option are different. It is imperative that the proper field wiring be installed according to the way the unit is built.

Overload Dial Setting

For units with 1 contactor and 1 overload per compressor:

The Overload must be set at a “Must Hold Dial Setting” equal to 125% of the compressor RLA listed on the unit data plate.

For units with 2 contactors and 2 overloads per compressor:

The Overload must be set at a “Must Hold Dial Setting” equal to 125% of half the compressor RLA listed on the unit data plate.

Notes:

The “Must Trip Amps” is 12% higher than the “Must Hold Dial Setting”.

The accuracy of the Overload Setting is ±2%.

Table 39. Electrical data single point (70 thru 100)

ALS

UNIT

SIZE

070A

080A

090A

100A

VOLTS

460

575

208

230

380

460

575

208

208

230

380

460

575

208

230

380

230

380

460

575

HZ

60

60

60

60

MINIMUM

CIRCUIT

AMPACITY

(MCA)

187

150

475

434

262

216

173

475

335

307

185

153

124

410

375

227

434

262

216

173

QTY.

POWER SUPPLY

FIELD WIRE

WIRE

GAUGE

QTY.

3

6

3

3

6

6

3

3

3

3

6

3

3

3

3

3

3

3

3

3

3/0

1/0

350

300

300

4/0

2/0

350

400

350

3/0

2/0

#1

600

500

4/0

300

300

4/0

2/0

1

2

1

1

2

2

1

1

1

1

2

1

1

1

1

1

1

1

1

1

Table based on 75°C field wire per NEC.

HUB

NOMINAL

SIZE

2.5

2.0

1.5

2.5

1.5

1.5

2.5

2.5

2.5

2.5

2.0

1.5

1.5

3.0

3.0

2.0

3.0

2.5

2.0

1.5

FIELD FUSE SIZE

RECOM-

MENDED

MAXIMUM

250

200

600

600

350

300

225

600

500

400

250

200

175

500

500

300

600

350

300

225

300

250

800

700

450

350

250

800

500

500

300

250

200

700

600

350

700

450

350

250

IM 548 / Page 29

Wire Sizing Ampacities

Table 40. Electrical data single point (125 thru 204)

ALS

UNIT

SIZE

125A

140A

155A

170A

175A

185A

195A

204A

VOLTS

575

208*

230

380

460

575

208*

230

230

380

460

575

208

230

380

460

380

460

575

208*

230

380

460

575

460

575

208

230

380

460

575

208

208

230

380

460

575

208

230

380

HZ

60

60

60

60

60

60

60

60

MINIMUM

CIRCUIT

AMPACITY

(MCA)

296

853*

779

471

388

311

853*

779

730

441

364

292

810

741

448

369

471

388

311

881*

799

481

399

321

307

247

745

682

412

340

273

799

598

548

331

273

221

673

616

372

QTY.

POWER SUPPLY

FIELD WIRE

WIRE

GAUGE

QTY.

6

6

6

3

6

6

3

6

6

3

6

6

3

3

6

6

6

3

6

6

3

6

6

6

3

6

6

3

6

6

3

3

6

3

3

6

3

3

6

6

350

600*

600

250

#3/0

400

600*

600

500

#4/0

500

350

600

500

250

500

250

#3/0

400

600*

600

250

#3/0

400

350

250

500

500

#4/0

500

300

600

350

300

400

300

4/0

500

350

500

2

2

2

1

2

2

1

2

2

1

2

2

1

1

2

2

2

1

2

2

1

2

2

2

1

2

2

1

2

2

1

1

2

1

1

2

1

1

2

2

*Field wire size values apply to 90°C rated wire per NEC.

HUB

NOMINAL

SIZE

2.0

2.5

3.0

3.0

2.5

3.0

3.0

2.5

3.0

3.0

2.5

3.0

3.0

2.0

3.0

2.5

3.0

2.5

2.0

2.5

2.5

2.0

2.5

3.0

2.0

3.0

2.5

3.0

2.5

2.5

3.0

3.0

2.0

3.0

2.5

3.0

2.5

2.5

3.0

2.5

FIELD FUSE SIZE

RECOM-

MENDED

MAXIMUM

350

1000

1000

500

450

350

1000

1000

800

500

450

350

1000

1000

500

450

500

450

350

1000

1000

500

500

400

400

300

800

800

500

400

300

1000

700

600

400

300

250

800

700

450

400

1000

1000

600

500

400

1000

1000

1000

600

500

400

1000

1000

600

500

600

500

400

1200

1000

600

500

400

400

350

1000

800

500

450

350

1000

800

700

450

350

300

800

800

500

Page 30 / IM 548

Table 41. Electrical data single point (205 thru 380)

ALS

UNIT

SIZE

205A

220A

235A

250A

265A

280A

300A

315A

330A

340A

360A

370A

380A

VOLTS

380

460

575

380*

460

575

380*

460

575

380*

460

575

575

380

460

575

380

460

575

380

460

575

380

460

575

380

460

575

380

460

575

380

460

575

380

460

575

380

460

HZ

60

60

60

60

60

60

60

60

60

60

60

60

60

MINIMUM

CIRCUIT

AMPACITY

(MCA)

818

674

542

859

707

569

882

726

584

905

745

599

444

723

596

481

756

623

502

789

650

523

525

433

349

558

460

370

597

492

395

626

516

414

649

535

429

672

554

QTY.

POWER SUPPLY

FIELD WIRE

WIRE

GAUGE

QTY.

6

6

6

6

6

6

6

6

6

6

6

6

6

6

6

6

6

6

6

6

6

6

6

6

6

6

6

6

2

6

6

6

6

6

6

6

6

6

6

600

500

300

600

500

300

600

500

350

600

500

350

#4/0

500

350

250

500

400

250

600

400

300

300

#4/0

#3/0

300

#4/0

#3/0

350

250

#3/0

400

300

#4/0

400

300

#4/0

500

300

2

2

2

2

2

2

2

2

2

2

2

2

2

2

2

2

2

2

2

2

2

2

2

2

2

2

2

2

2

2

2

2

2

2

2

2

2

2

2

* Table based on 75°C field wire except for 380V ALS360, 370 and 380 which require 90°C field wire.

HUB

NOMINAL

SIZE

3.0

3.0

2.0

3.0

3.0

2.0

3.0

3.0

2.5

3.0

3.0

2.5

3.0

2.5

2.0

3.0

2.5

2.0

2.0

3.0

2.5

2.0

2.0

1.5

2.5

2.0

1.5

2.5

2.0

2.0

1.5

2.0

2.0

2.0

2.5

2.0

2.0

3.0

2.0

FIELD FUSE SIZE

RECOM-

MENDED

MAXIMUM

1000

800

600

1000

800

600

1000

800

700

1000

800

700

500

800

700

500

800

700

600

800

700

600

600

500

400

700

500

450

700

600

450

700

600

500

800

600

500

800

600

1000

800

600

1000

800

600

1000

800

700

1000

800

700

500

800

700

500

800

700

600

800

700

600

600

500

450

700

500

450

700

600

500

800

600

500

800

600

500

800

700

IM 548 / Page 31

Table 42. Electrical data multiple point (125 thru 204)

460

575

208

230

380

460

380

460

575

208

230

380

575

208

230

380

460

575

230

380

460

575

208

230

208

230

380

460

575

208

208

230

380

460

575

208

230

380

460

575

ALS

UNIT VOLTS HZ

SIZE

125A

140A

155A

170A

175A

185A

195A

204A

60

60

60

60

60

60

60

60

214

171

470

429

259

214

230

190

152

470

429

259

171

484

439

284

219

176

375

226

187

150

416

381

410

375

226

187

150

410

329

301

182

150

122

329

301

182

150

122

MINIMUM

CIRCUIT

AMPS

(MCA)

FIELD WIRE

QTY.

WIRE

GAUGE

6

3

3

3

3

6

6

6

3

3

3

3

3

3

3

3

6

6

3

6

6

3

3

3

3

3

6

6

3

3

3

3

3

3

3

3

3

3

3

3

ELECTRICAL CIRCUIT #1

POWER SUPPLY

#4/0

#2/0

250

#4/0

300

#4/0

#4/0

#3/0

#2/0

250

#4/0

300

#2/0

250

#4/0

300

#4/0

#3/0

500

#4/0

#3/0

#1/0

#4/0

#3/0

#4/0

500

#4/0

#3/0

#1/0

#4/0

400

350

#3/0

#1/0

#1

400

350

#3/0

#1/0

#1

HUB

QTY.

2

1

1

1

1

2

2

2

1

1

1

1

1

1

1

1

2

2

1

2

2

1

1

1

1

1

2

2

1

1

1

1

1

1

1

1

1

1

1

1

HUB

SIZE

2.0

1.5

2.5

2.0

2.5

2.0

2.0

2.0

1.5

2.5

2.0

2.5

1.5

2.5

2.0

2.5

2.0

2.0

3.0

2.0

2.0

1.5

2.0

2.0

2.0

3.0

2.0

2.0

1.5

2.0

1.5

3.0

2.5

2.0

1.5

1.5

3.0

2.5

2.0

1.5

FIELD FUSING

REC.

FUSE

SIZE

MAX.

FUSE

SIZE

250

225

600

500

350

250

300

250

200

600

500

350

225

700

600

400

300

250

500

300

250

200

500

500

500

500

300

250

200

500

400

400

225

200

150

400

400

225

200

150

350

250

800

700

400

350

350

300

250

800

700

400

250

800

700

450

350

300

600

350

300

250

700

600

700

600

350

300

250

700

500

500

300

250

200

500

500

300

250

200

MINIMUM

CIRCUIT

AMPS

(MCA)

ELECTRICAL CIRCUIT #2

POWER SUPPLY

FIELD WIRE

QTY.

WIRE

GAUGE

HUB

QTY.

HUB

SIZE

214

171

470

429

259

214

259

214

171

470

429

259

171

484

439

264

219

176

423

255

211

169

470

429

410

375

226

187

150

464

329

301

182

150

122

404

369

223

184

148

6

3

3

3

3

6

6

6

3

3

3

3

3

3

3

3

6

6

3

6

6

6

3

3

3

3

6

6

3

3

3

3

3

3

6

3

3

3

3

3

#4/0

#2/0

250

#4/0

300

#4/0

300

#4/0

#2/0

250

#4/0

300

#2/0

250

#4/0

300

#4/0

#3/0

#4/0

250

#4/0

#2/0

250

#4/0

#4/0

500

#4/0

#3/0

#1/0

250

400

350

#3/0

#1/0

#1

#4/0

500

#4/0

#3/0

#1/0

1

1

1

1

1

1

1

1

1

1

1

1

1

1

1

1

2

2

1

2

2

2

1

1

1

1

2

2

1

1

1

1

1

1

2

1

1

1

1

1

2.0

1.5

2.5

2.0

2.5

2.0

2.5

2.0

1.5

2.5

2.0

2.5

1.5

2.5

2.0

2.5

2.0

2.0

2.0

2.5

2.0

1.5

2.5

2.0

2.0

3.0

2.0

2.0

1.5

2.5

1.5

2.0

3.0

2.0

2.0

1.5

3.0

2.5

2.0

1.5

FIELD FUSING

REC.

FUSE

SIZE

MAX.

FUSE

SIZE

250

225

600

500

350

250

350

250

225

600

500

350

225

700

600

400

300

250

500

350

250

225

600

500

500

500

300

250

200

600

400

400

225

200

150

500

500

300

250

200

350

250

800

700

400

350

400

350

250

800

700

400

250

800

700

450

350

300

700

400

350

250

800

700

700

600

350

300

250

800

500

500

300

250

200

700

600

350

300

250

Page 32 / IM 548

230

380

460

575

208

230

208

230

380

460

575

208

380

460

575

208

230

380

460

575

208

230

380

460

575

208

230

380

460

575

Table 43. Electrical data multiple point (205 thru 280)

ALS

UNIT VOLTS HZ

SIZE

205A

220A

235A

250A

265A

280A

60

60

60

60

60

60

375

227

187

150

410

375

410

375

227

187

150

410

227

187

150

464

423

256

211

170

329

302

182

150

122

329

302

182

150

122

MINIMUM

CIRCUIT

AMPS

(MCA)

FIELD WIRE

QTY.

WIRE

GAUGE

3

6

6

6

3

3

3

3

6

6

6

3

6

6

3

3

3

3

3

3

3

3

3

3

3

3

3

3

3

3

ELECTRICAL CIRCUIT #1

POWER SUPPLY

250

#4/0

#3/0

#1/0

300

250

300

250

#4/0

#3/0

#1/0

300

#4/0

#3/0

#1/0

350

300

250

#4/0

#2/0

400

350

#3/0

#1/0

#1/0

400

350

#3/0

#1/0

#1/0

HUB

QTY.

1

1

1

1

1

1

1

1

1

1

1

1

1

1

1

1

1

1

1

1

1

1

1

1

1

1

1

1

1

1

HUB

SIZE

3

2

1.5

1.25

3

3

3

3

2

1.5

1.25

3

2

1.5

1.25

3.5

3

2

2

1.5

2.5

2.5

1.5

1.25

1.25

2.5

2.5

1.5

1.25

1.25

FIELD FUSING

REC.

FUSE

SIZE

MAX.

FUSE

SIZE

500

300

250

200

600

500

600

500

300

250

200

600

300

250

200

700

600

350

300

250

400

400

250

200

175

400

400

250

200

175

600

350

300

250

700

600

700

600

350

300

250

700

350

300

250

800

700

400

350

250

500

500

300

250

200

500

500

300

250

200

Note: Electrical circuit #3 is continued on next page.

MINIMUM

CIRCUIT

AMPS

(MCA)

ELECTRICAL CIRCUIT #2

POWER SUPPLY

FIELD WIRE

QTY.

WIRE

GAUGE

HUB

QTY.

HUB

SIZE

375

227

187

150

464

423

410

375

227

187

150

410

256

211

170

464

423

256

211

170

329

302

182

150

122

410

375

223

187

150

3

6

6

6

3

3

3

3

6

6

6

3

6

6

3

3

3

3

3

3

3

3

3

3

6

6

3

3

3

3

250

#4/0

#3/0

#1/0

350

300

300

250

#4/0

#3/0

#1/0

300

250

#4/0

#2/0

350

300

250

#4/0

#2/0

400

350

#3/0

#1/0

#1/0

300

250

#4/0

#3/0

#1/0

1

1

1

1

1

1

1

1

1

1

1

1

1

1

1

1

1

1

1

1

1

1

1

1

1

1

1

1

1

1

3

2

1.5

1.25

3.5

3

3

3

2

1.5

1.25

3

2

2

1.5

3.5

3

2

2

1.5

2.5

2.5

1.5

1.25

1.25

3

3

2

1.5

1.25

FIELD FUSING

REC.

FUSE

SIZE

500

300

250

200

700

600

600

500

300

250

200

600

350

300

250

700

600

350

300

250

400

400

250

200

175

600

500

300

250

200

MAX.

FUSE

SIZE

600

350

300

250

800

700

700

600

350

300

250

700

400

350

250

800

700

400

350

250

500

500

300

250

200

700

600

350

300

250

IM 548 / Page 33

Page 34 / IM 548

Table 43. Electrical data multiple point (205 thru 280 continued)

575

208

230

380

460

575

230

380

460

575

208

230

380

460

460

575

208

230

380

460

575

208

208

230

380

460

575

208

230

380

ALS

UNIT VOLTS HZ

SIZE

205A

220A

235A

250A

265A

280A

60

60

60

60

60

60

ELECTRICAL CIRCUIT #3

MINIMUM

CIRCUIT

AMPS

(MCA)

POWER SUPPLY

FIELD WIRE

QTY.

WIRE

GAUGE

HUB

QTY.

HUB

SIZE

FIELD FUSING

REC.

FUSE

SIZE

MAX.

FUSE

SIZE

170

464

423

256

211

170

423

256

211

170

464

423

256

211

187

150

410

375

227

187

150

464

410

375

227

187

150

410

375

227

6

3

3

6

3

3

3

3

6

6

3

3

6

3

3

6

3

3

6

6

3

3

6

3

3

6

3

3

6

6

#2/0

350

300

250

#4/0

#2/0

300

250

#4/0

#2/0

350

300

250

#4/0

#3/0

#1/0

300

250

#4/0

#3/0

#1/0

350

300

250

#4/0

#3/0

#1/0

300

250

#4/0

1

1

1

1

1

1

1

1

1

1

1

1

1

1

1

1

1

1

1

1

1

1

1

1

1

1

1

1

1

1

1.5

3.5

3.0

2.0

2.0

1.5

3.5

3.0

2.0

2.0

3.0

2.0

2.0

1.5

1.5

1.25

3.0

3.0

2.0

1.5

1.25

3.5

3.0

3.0

2.0

1.5

1.25

3.0

3.0

2.0

250

700

600

350

300

250

600

350

300

250

700

600

350

300

250

200

600

500

300

250

200

700

600

500

300

250

200

600

500

300

250

800

700

400

350

250

700

400

350

250

800

700

400

350

300

250

700

600

350

300

250

800

700

600

350

300

250

700

600

350

230

380

460

575

208

230

208

230

380

460

575

208

208

230

380

460

575

208

230

380

460

575

460

575

208*

230

380

460

575

380

460

575

208*

230

380

Table 44. Electrical data multiple point (300 thru 380)

ALS

UNIT VOLTS HZ

SIZE

300A

315A

330A

340A

360A

370A

380A

60

60

60

60

60

60

60

3

6

6

6

6

3

3

3

6

6

6

6

6

3

3

3

6

6

6

6

6

3

6

6

3

3

3

6

3

6

6

6

6

3

3

500

300

500

300

600

500

500

500

300

500

300

500

500

400

250

400

250

500

400

250

400

250

500

350

600

600

350

600

400

300

500

350

600

500

300

ELECTRICAL CIRCUIT #1 (COMP’S #1 & #3)

POWER SUPPLY FIELD FUSING

MINIMUM

CIRCUIT

AMPS

(MCA)

FIELD WIRE

QTY.

WIRE

GAUGE

HUB

QTY.

HUB

SIZE

REC.

FUSE

SIZE

MAX.

FUSE

SIZE

684

415

342

275

822

746

753

684

415

342

275

753

693

630

382

315

254

693

630

382

315

254

373

300

865

784

476

392

315

453

373

300

822

746

453

1

2

2

2

1

1

1

1

2

2

2

1

1

1

1

1

2

2

2

2

1

1

2

1

1

1

1

2

1

2

2

1

1

1

1

3.0

3.0

3.0

2.0

3.0

3.0

3.0

3.0

3.0

3.0

2.0

3.0

2.0

3.0

2.5

3.0

2.5

2.0

3.0

2.5

3.0

2.5

3.0

2.5

3.0

3.0

3.5

3.0

2.5

3.0

3.0

2.5

3.0

3.0

3.0

800

500

400

350

1000

1000

1000

800

500

400

350

1000

800

800

450

400

350

800

800

450

400

350

450

400

1000

1000

500

450

400

500

450

400

1000

1000

500

800

500

450

350

1000

1000

1000

800

500

450

350

1000

800

800

500

450

350

800

800

500

450

350

500

400

1000

1000

600

500

400

600

500

400

1000

1000

600

3

6

6

6

6

3

3

3

6

6

6

6

6

3

3

3

6

6

6

6

6

3

6

6

3

3

3

6

3

6

6

6

6

3

3

500

300

500

350

600

500

500

500

300

500

300

600

500

400

250

400

250

500

400

300

400

250

600

400

600

600

350

600

400

300

500

350

600

600

350

MINIMUM

CIRCUIT

AMPS

(MCA)

ELECTRICAL CIRCUIT #2 (COMP’S #2 & #4)

POWER SUPPLY FIELD FUSING

FIELD WIRE

QTY.

WIRE

GAUGE

HUB

QTY.

HUB

SIZE

REC.

FUSE

SIZE

MAX.

FUSE

SIZE

732

444

366

294

822

746

753

684

415

342

275

807

693

630

382

315

254

753

684

415

342

275

392

315

865

784

476

392

315

453

373

300

865

784

476

1

2

2

2

1

1

1

1

2

2

2

1

1

1

1

1

2

2

2

2

1

1

2

1

1

1

1

2

1

2

2

1

1

1

1

3.0

3.0

3.0

2.5

3.0

3.0

3.0

3.0

3.0

3.0

2.0

3.0

2.0

3.0

3.0

3.0

3.0

2.0

3.0

2.5

3.0

2.5

3.0

2.5

3.0

3.0

3.5

3.0

2.5

3.0

3.0

2.5

3.0

3.0

3.5

1000

500

450

350

1000

1000

1000

800

500

400

350

1000

800

800

450

400

350

1000

800

500

400

350

450

400

1000

1000

500

450

400

500

450

400

1000

1000

500

1000

600

500

400

1000

1000

1000

800

500

450

350

1000

800

800

500

450

350

1000

800

500

450

350

500

400

1000

1000

600

500

400

600

500

400

1000

1000

600

Compressor and Condenser Fan Motors

Table 45. Compressor and condenser fan motor amp draw (70 thru 100)

RATED LOAD AMPS

ALS

UNIT

SIZE

070A

080A

090A

100A

VOLTS

208

230

380

460

575

208

230

380

460

575

208

230

380

460

575

208

230

380

460

575

HZ

60

60

60

60

COMPRESSOR

343

310

188

155

124

343

310

188

155

124

240

218

132

109

88

300

272

165

136

109

FAN

MOTORS

FLA

(EACH)

5.8

3.4

2.8

2.3

5.8

5.8

3.4

2.8

2.3

5.8

2.3

5.8

5.8

3.4

2.8

2.3

5.8

5.8

3.4

2.8

NO. OF

FAN

MOTORS

8

8

8

8

8

8

8

8

8

8

6

6

6

6

6

6

6

6

6

6

FAN

MOTORS

(EACH)

23.7

21.4

14.4

10.7

11.5

23.7

21.4

14.4

10.7

11.5

23.7

21.4

14.4

10.7

11.5

23.7

21.4

14.4

10.7

11.5

LOCKED ROTOR AMPS

COMPRESSOR

ACROSS-THE-LINE REDUCED INRUSH

1459

1628

943

764

589

1459

1628

943

764

589

1459

1628

943

764

589

1459

1628

943

764

589

934

1042

604

489

377

934

1042

604

489

377

934

1042

604

489

377

934

1042

604

489

377

IM 548 / Page 35

Table 46. Compressor and condenser fan motor amp draw (125 thru 204)

ALS

UNIT

SIZE

125A

140A

155A

170A

175A

185A

195A

204A

VOLTS

575

208

230

380

460

575

208

230

230

380

460

575

208

230

380

460

380

460

575

208

230

380

460

575

460

575

208

230

380

460

575

208

208

230

380

460

575

208

230

380

H

Z

60

60

60

60

60

60

60

60

RATED LOAD AMPS

COMPRESSOR

NO. 1

109

343

310

188

155

124

343

310

272

165

136

109

300

272

165

136

188

155

124

343

310

188

155

124

109

88

300

272

165

136

109

300

240

218

132

109

88

240

218

132

NO. 2

FAN

MOTORS

FLA

(EACH)

2.8

2.3

5.8

5.8

2.3

5.8

5.8

3.4

5.8

5.8

3.4

2.8

5.8

3.4

2.8

2.3

7.2

4.1

3.6

3.0

3.4

2.8

2.3

7.8

3.4

2.8

2.3

5.8

2.8

2.3

5.8

5.8

2.3

5.8

5.8

3.4

5.8

5.8

3.4

2.8

NO. OF

FAN

MOTORS

124

343

310

188

155

124

343

310

310

188

155

124

343

310

188

155

188

155

124

343

310

188

155

124

136

109

300

272

165

136

109

343

240

218

132

109

88

300

272

165

14

14

14

14

14

14

14

14

14

14

14

14

12

12

12

12

14

14

14

14

14

14

14

14

12

12

12

12

10

10

12

12

10

10

10

10

10

10

10

10

FAN

MOTORS

(EACH)

11.5

23.7

21.4

14.4

10.7

11.5

23.7

21.4

21.4

14.4

10.7

11.5

23.7

21.4

14.4

10.7

14.4

10.7

11.5

30.5

27.6

20.0

13.8

11.5

10.7

11.5

23.7

21.4

14.4

10.7

11.5

23.7

23.7

21.4

14.4

10.7

11.5

23.7

21.4

14.4

LOCKED ROTOR AMPS

COMPRESSOR

ACROSS-THE-LINE REDUCED INRUSH

589

1459

1628

943

764

589

1459

1628

1628

943

764

589

1459

1628

943

764

943

764

589

1459

1628

943

764

589

764

589

1459

1628

943

764

589

1459

1459

1628

943

764

589

1459

1628

943

377

934

1042

604

489

377

934

1042

1042

604

489

377

934

1042

604

489

604

489

377

934

1042

604

489

377

489

377

934

1042

604

489

377

934

934

1042

604

489

377

934

1042

604

Page 36 / IM 548

Table 47. Compressor and condenser fan motor amp draw (205 thru 280)

ALS

UNIT

SIZE

VOLTAGE HZ

RATED LOAD AMPS

COMPRESSORS

NO. 1 NO. 2 NO. 3

FAN

MOTORS

FLA

(EACH)

NO. OF

FAN

MOTORS

205A

220A

235A

250A

265A

280A

575

208

230

380

460

575

230

380

460

575

208

230

380

460

460

575

208

230

380

460

575

208

208

230

380

460

575

208

230

380

60

60

60

60

60

60

109

343

310

188

155

124

272

165

136

109

300

272

165

136

109

88

300

272

165

136

109

300

240

218

132

109

88

240

218

132

124

343

310

188

155

124

272

165

136

109

343

310

188

155

136

109

300

272

165

136

109

300

240

218

132

109

88

300

272

165

124

343

310

188

155

124

310

188

155

124

343

310

188

155

136

109

300

272

165

136

109

343

300

272

165

136

109

300

272

165

2.3

5.8

5.8

3.4

2.8

2.3

5.8

5.8

3.4

2.8

5.8

3.4

2.8

2.3

3.4

2.8

2.3

5.8

2.8

2.3

5.8

5.8

2.3

5.8

5.8

3.4

5.8

5.8

3.4

2.8

18

18

18

18

18

18

18

18

18

18

18

18

18

18

18

18

18

18

16

16

18

18

16

16

16

16

16

16

16

16

FAN

MOTORS

(EACH)

11.5

23.7

21.4

14.4

10.7

11.5

21.4

14.4

10.7

11.5

23.7

21.4

14.4

10.7

10.7

11.5

23.7

21.4

14.4

10.7

11.5

23.7

23.7

21.4

14.4

10.7

11.5

23.7

21.4

14.4

LOCKED ROTOR AMPS

PER COMPRESSOR

ACROSS-THE-LINE REDUCED IN RUSH

589

1459

1628

943

764

589

1628

943

764

589

1459

1628

943

764

764

589

1459

1628

943

764

589

1459

1459

1628

943

764

589

1459

1628

943

377

934

1042

604

489

377

1042

604

489

377

934

1042

604

489

489

377

934

1042

604

489

377

934

934

1042

604

489

377

934

1042

604

IM 548 / Page 37

Table 48. Compressor and condenser fan motor amp draw (300 thru 380)

ALS

UNIT VOLTS HZ

SIZE

NO. 1

RATED LOAD AMPS

COMPRESSORS

NO. 2 NO. 3 NO. 4

FAN

MOTORS

FLA

(EACH)

NO. OF

FAN

MOTORS

300A

315A

330A

340A

360A

370A

380A

575

208

230

380

460

575

208

230

230

380

460

575

208

230

380

460

380

460

575

460

575

208

230

380

460

575

208

208

230

380

460

575

208

230

380

60

60

60

60

60

60

60

109

300

272

165

136

109

343

310

272

165

136

109

300

272

165

136

188

155

124

109

88

300

272

165

136

109

300

240

218

132

109

88

240

218

132

109

343

310

188

155

124

343

310

272

165

136

109

300

272

165

136

188

155

124

136

109

300

272

165

136

109

300

240

218

132

109

88

300

272

165

124

343

310

188

155

124

343

310

272

165

136

109

343

310

188

155

188

155

124

136

109

300

272

165

136

109

300

300

272

165

136

109

300

272

165

124

343

310

188

155

124

343

310

310

188

155

124

343

310

188

155

188

155

124

136

109

300

272

165

136

109

343

300

272

165

136

109

300

272

165

3.6

3.0

7.8

7.2

3.0

7.8

7.2

4.1

7.8

7.2

4.1

3.6

7.2

4.1

3.6

3.0

4.1

3.6

3.0

4.1

3.6

3.0

7.8

3.6

3.0

7.8

7.2

3.0

7.8

7.2

4.1

7.8

7.2

4.1

3.6

24

24

24

24

24

24

24

24

24

24

24

24

24

24

24

20

20

20

20

20

20

20

20

20

20

20

20

20

20

20

20

20

20

20

20

FAN

MOTORS

(EACH)

11.5

30.5

27.6

20.0

13.8

11.5

30.5

27.6

27.6

20.0

13.8

11.5

30.5

27.6

20.0

13.8

20.0

13.8

11.5

13.8

11.5

30.5

27.6

20.0

13.8

11.5

30.5

30.5

27.6

20.0

13.8

11.5

30.5

27.6

20.0

LOCKED ROTOR AMPS

PER COMPRESSOR

ACROSS-THE-LINE REDUCED INRUSH

589

1459

1628

943

764

589

1459

1628

1628

943

764

589

1459

1628

943

764

943

764

589

764

589

1459

1628

943

764

589

1459

1459

1628

943

764

589

1459

1628

943

377

934

1042

604

489

377

934

1042

1042

604

489

377

934

1042

604

489

604

489

377

489

377

934

1042

604

489

377

934

934

1042

604

489

377

934

1042

604

Page 38 / IM 548

460

575

208

230

380

460

575

208

230

380

460

575

208

230

380

460

575

208

230

380

380

460

575

208

230

380

460

575

575

208

230

380

460

575

208

230

230

380

460

575

208

230

380

460

460

575

208

230

380

460

575

208

208

230

380

460

575

208

230

380

Customer Wiring

Table 49. Customer wiring information with single point power (70 thru 204)

ALS

UNIT SIZE

070A

080A

090A

100A

125A

140A

155A

170A

175A

185A

195A

204A

VOLTS HZ

60

60

60

60

60

60

60

60

60

60

60

60

WIRING TO UNIT POWER BLOCK

POWER BLOCK

TERMINAL SIZE CONNECTOR WIRE RANGE

AMPS (COPPER WIRE ONLY)

840

840

950

840

840

840

840

950

840

840

840

840

840

840

840

840

840

950

840

840

840

840

840

840

840

840

840

840

840

840

840

840

840

840

840

840

840

840

840

840

840

840

840

840

840

840

840

840

840

840

840

840

840

840

840

840

840

840

840

840

(2) #2 to 600 MCM

(2) #2 to 600 MCM

(2) #2 to 600 MCM

(2) #2 to 600 MCM

(2) #2 to 600 MCM

(2) #2 to 600 MCM

(2) #2 to 600 MCM

(2) #2 to 600 MCM

(2) #2 to 600 MCM

(2) #2 to 600 MCM

(2) #2 to 600 MCM

(2) #2 to 600 MCM

(2) #2 to 600 MCM

(2) #2 to 600 MCM

(2) #2 to 600 MCM

(2) #2 to 600 MCM

(2) #2 to 600 MCM

(2) #2 to 600 MCM

(2) #2 to 600 MCM

(2) #2 to 600 MCM

(2) #2 to 600 MCM

(2) #2 to 600 MCM

(2) #2 to 600 MCM

(2) #2 to 600 MCM

(2) #2 to 600 MCM

(2) #2 to 600 MCM

(2) #2 to 600 MCM

(2) #2 to 600 MCM

(2) #2 to 600 MCM

(2) #2 to 600 MCM

(2) #2 to 600 MCM

(2) #2 to 600 MCM

(2) #2 to 600 MCM

(2) #2 to 600 MCM

(2) #2 to 600 MCM

(2) #2 to 600 MCM

(2) #2 to 600 MCM

(2) #2 to 600 MCM

(2) #2 to 600 MCM

(2) #2 to 600 MCM

(2) #2 to 600 MCM

(2) #2 to 600 MCM

(2) #2 to 600 MCM

(2) #2 to 600 MCM

(2) #2 to 600 MCM

(2) #2 to 600 MCM

(2) #2 to 600 MCM

(2) #2 to 600 MCM

(2) #2 to 600 MCM

(2) #2 to 600 MCM

(2) #2 to 600 MCM

(2) #2 to 600 MCM

(2) #2 to 600 MCM

(2) #2 to 600 MCM

(2) #2 to 600 MCM

(2) #2 to 600 MCM

(2) #2 to 600 MCM

(2) #2 to 600 MCM

(2) #2 to 600 MCM

(2) #2 to 600 MCM

WIRING TO DISCONNECT SWITCH

OPTIONAL DISCONNECT SWITCH

SIZE

CONNECTOR WIRE RANGE

(COPPER WIRE ONLY)

(2) 250 to 500 MCM

(1) 250 to 500 MCM

(1) 250 to 500 MCM

See note 9

See note 9

(2) 250 to 500 MCM

(1) 250 to 500 MCM

(1) 250 to 500 MCM

See note 9

See note 9

(2) 250 to 500 MCM

(1) 250 to 500 MCM

(1) 250 to 500 MCM

See note 9

See note 9

(2) 250 to 500 MCM

(2) 250 to 500 MCM

(1) 250 to 500 MCM

See note 9

See note 9

(2) 250 to 500 MCM

(2) 250 to 500 MCM

(1) 250 to 500 MCM

See note 9

See note 9

(2) 250 to 500 MCM

(2) 250 to 500 MCM

(1) 250 to 500 MCM

(1) 250 to 500 MCM

(1) 250 to 500 MCM

(1) 250 to 500 MCM

(1) #2 to 3/0

(1) #2 to 3/0

(1) 250 to 500 MCM

(1) 250 to 500 MCM

(1) #4 to 350 MCM

(1) #4 to 350 MCM

(1) #2 to 3/0

(1) 250 to 500 MCM

(1) 250 to 500 MCM

(1) #4 to 350 MCM

(1) #4 to 350 MCM

(1) #4 to 350 MCM

(1) 250 to 500 MCM

(1) 250 to 500 MCM

(1) #4 to 350 MCM

(1) #4 to 350 MCM

(1) #4 to 350 MCM

See note 9

See note 9

(1) 250 to 500 MCM

(1) 250 to 500 MCM

(1) #4 to 350 MCM

See note 9

See note 9

(1) 250 to 500 MCM

(1) 250 to 500 MCM

(1) 250 to 500 MCM

See note 9

See note 9

600

400

—

—

600

600

400

—

—

600

600

400

—

—

600

400

400

—

—

600

600

400

400

—

—

600

400

400

250

—

—

400

400

400

—

—

400

250

250

250

—

—

400

400

250

150

600

400

250

250

250

600

400

400

400

150

150

400

400

250

IM 548 / Page 39

380

460

575

380

460

575

380

460

460

575

380

460

575

380

460

575

575

380

460

575

380

460

575

575

380

460

575

380

460

575

380

380

460

575

380

460

575

380

460

Table 50. Customer wiring information with single point power (205 thru 380)

ALS

UNIT SIZE

205A

220A

235A

250A

265A

280A

300A

315A

330A

340A

360A

370A

380A

VOLTS HZ

60

60

60

60

60

60

60

60

60

60

60

60

60

WIRING TO UNIT POWER BLOCK

POWER BLOCK

TERMINAL SIZE CONNECTOR WIRE RANGE

AMPS (COPPER WIRE ONLY)

840

840

840

840

840

840

950

840

840

840

840

840

840

840

840

840

840

950

840

840

950

840

840

840

840

840

840

840

840

840

840

840

840

840

840

840

840

840

840

(2) #2 to 600 MCM

(2) #2 to 600 MCM

(2) #2 to 600 MCM

(2) #2 to 600 MCM

(2) #2 to 600 MCM

(2) #2 to 600 MCM

(2) #2 to 600 MCM

(2) #2 to 600 MCM

(2) #2 to 600 MCM

(2) #2 to 600 MCM

(2) #2 to 600 MCM

(2) #2 to 600 MCM

(2) #2 to 600 MCM

(2) #2 to 600 MCM

(2) #2 to 600 MCM

(2) #2 to 600 MCM

(2) #2 to 600 MCM

(2) #2 to 600 MCM

(2) #2 to 600 MCM

(2) #2 to 600 MCM

(2) #2 to 600 MCM

(2) #2 to 600 MCM

(2) #2 to 600 MCM

(2) #2 to 600 MCM

(2) #2 to 600 MCM

(2) #2 to 600 MCM

(2) #2 to 600 MCM

(2) #2 to 600 MCM

(2) #2 to 600 MCM

(2) #2 to 600 MCM

(2) #2 to 600 MCM

(2) #2 to 600 MCM

(2) #2 to 600 MCM

(2) #2 to 600 MCM

(2) #2 to 600 MCM

(2) #2 to 600 MCM

(2) #2 to 600 MCM

(2) #2 to 600 MCM

(2) #2 to 600 MCM

1200

800

600

1200

800

600

1200

800

600

600

800

800

600

1200

800

600

800

1200

800

800

1200

1200

800

600

800

600

600

800

600

600

800

600

600

400

600

600

400

800

600

WIRING TO DISCONNECT SWITCH

OPTIONAL DISCONNECT SWITCH

SIZE

CONNECTOR WIRE RANGE

(COPPER WIRE ONLY)

(2) 250 to 500 MCM

(2) 250 to 500 MCM

(1) 250 to 500 MCM

(2) 250 to 500 MCM

(2) 250 to 500 MCM

(1) 250 to 500 MCM

(2) 500 to 750 MCM

(2) 250 to 500 MCM

(2) 250 to 500 MCM

(2) 500 to 750 MCM

(2) 250 to 500 MCM

(2) 250 to 500 MCM

(2) 500 to 750 MCM

(2) 250 to 500 MCM

(2) 250 to 500 MCM

(2) 500 to 750 MCM

(2) 250 to 500 MCM

(2) 250 to 500 MCM

(2) 400 to 700 MCM

(2) 400 to 700 MCM

(2) 250 to 500 MCM

(3) 500 to 750 MCM

(2) 400 to 700 MCM

(2) 250 to 500 MCM

(3) 500 to 750 MCM

(2) 400 to 700 MCM

(2) 250 to 500 MCM

(3) 500 to 750 MCM

(2) 400 to 700 MCM

(2) 250 to 500 MCM

(3) 500 to 750 MCM

(2) 400 to 700 MCM

(2) 400 to 700 MCM

(3) 500 to 750 MCM

(2) 400 to 700 MCM

(2) 400 to 700 MCM

(3) 500 to 750 MCM

(3) 500 to 750 MCM

(2) 400 to 700 MCM

Page 40 / IM 548

575

208

230

380

460

575

208

230

230

380

460

575

208

230

380

460

380

460

575

208

230

380

460

575

460

575

208

230

380

460

575

208

208

230

380

460

575

208

230

380

Table 51. Customer wiring information with multiple point power (125 thru 204)

ALS

UNIT SIZE

125A

140A

155A

170A

175A

185A

195A

204A

VOLTS HZ

60

60

60

60

60

60

60

60

TERMINAL SIZE (AMPS)

CKT 1 CKT 2

840

840

840

840

840

840

840

840

840

840

840

840

840

840

840

840

840

840

840

840

840

840

840

840

840

840

840

840

840

840

840

840

840

840

840

840

840

840

840

840

840

840

840

840

840

840

840

840

840

840

840

840

840

840

840

840

840

840

840

840

840

840

840

840

840

840

840

840

840

840

840

840

840

840

840

840

840

840

840

840

WIRING TO UNIT POWER BLOCK

POWER BLOCK

CONNECTOR WIRE RANGE (COPPER WIRE ONLY)

CKT 1 CKT 2

(2) #2 to 600 MCM

(2) #2 to 600 MCM

(2) #2 to 600 MCM

(2) #2 to 600 MCM

(2) #2 to 600 MCM

(2) #2 to 600 MCM

(2) #2 to 600 MCM

(2) #2 to 600 MCM

(2) #2 to 600 MCM

(2) #2 to 600 MCM

(2) #2 to 600 MCM

(2) #2 to 600 MCM

(2) #2 to 600 MCM

(2) #2 to 600 MCM

(2) #2 to 600 MCM

(2) #2 to 600 MCM

(2) #2 to 600 MCM

(2) #2 to 600 MCM

(2) #2 to 600 MCM

(2) #2 to 600 MCM

(2) #2 to 600 MCM

(2) #2 to 600 MCM

(2) #2 to 600 MCM

(2) #2 to 600 MCM

(2) #2 to 600 MCM

(2) #2 to 600 MCM

(2) #2 to 600 MCM

(2) #2 to 600 MCM

(2) #2 to 600 MCM

(2) #2 to 600 MCM

(2) #2 to 600 MCM

(2) #2 to 600 MCM

(2) #2 to 600 MCM

(2) #2 to 600 MCM

(2) #2 to 600 MCM

(2) #2 to 600 MCM

(2) #2 to 600 MCM

(2) #2 to 600 MCM

(2) #2 to 600 MCM

(2) #2 to 600 MCM

(2) #2 to 600 MCM

(2) #2 to 600 MCM

(2) #2 to 600 MCM

(2) #2 to 600 MCM

(2) #2 to 600 MCM

(2) #2 to 600 MCM

(2) #2 to 600 MCM

(2) #2 to 600 MCM

(2) #2 to 600 MCM

(2) #2 to 600 MCM

(2) #2 to 600 MCM

(2) #2 to 600 MCM

(2) #2 to 600 MCM

(2) #2 to 600 MCM

(2) #2 to 600 MCM

(2) #2 to 600 MCM

(2) #2 to 600 MCM

(2) #2 to 600 MCM

(2) #2 to 600 MCM

(2) #2 to 600 MCM

(2) #2 to 600 MCM

(2) #2 to 600 MCM

(2) #2 to 600 MCM

(2) #2 to 600 MCM

(2) #2 to 600 MCM

(2) #2 to 600 MCM

(2) #2 to 600 MCM

(2) #2 to 600 MCM

(2) #2 to 600 MCM

(2) #2 to 600 MCM

(2) #2 to 600 MCM

(2) #2 to 600 MCM

(2) #2 to 600 MCM

(2) #2 to 600 MCM

(2) #2 to 600 MCM

(2) #2 to 600 MCM

(2) #2 to 600 MCM

(2) #2 to 600 MCM

(2) #2 to 600 MCM

(2) #2 to 600 MCM

IM 548 / Page 41

Table 52. Customer wiring information with multiple point power (205 thru 280)

ALS

UNIT SIZE

205A

220A

235A

250A

265A

280A

VOLTS

575

208

230

380

460

575

230

380

460

575

208

230

380

460

460

575

208

230

380

460

575

208

208

230

380

460

575

208

230

380

HZ

60

60

60

60

60

60

TERMINAL SIZE (AMPS)

CKT 1 CKT 2 CKT 3

840

840

840

840

840

840

840

840

840

840

840

840

840

840

840

840

840

840

840

840

840

840

840

840

840

840

840

840

840

840

840

840

840

840

840

840

840

840

840

840

840

840

840

840

840

840

840

840

840

840

840

840

840

840

840

840

840

840

840

840

840

840

840

840

840

840

840

840

840

840

840

840

840

840

840

840

840

840

840

840

840

840

840

840

840

840

840

840

840

840

WIRING TO UNIT POWER BLOCK

POWER BLOCK

CKT 1

CONNECTOR WIRE RANGE (COPPER WIRE ONLY)

CKT 2 CKT 3

(2) #2 to 600 MCM

(2) #2 to 600 MCM

(2) #2 to 600 MCM

(2) #2 to 600 MCM

(2) #2 to 600 MCM

(2) #2 to 600 MCM

(2) #2 to 600 MCM

(2) #2 to 600 MCM

(2) #2 to 600 MCM

(2) #2 to 600 MCM

(2) #2 to 600 MCM

(2) #2 to 600 MCM

(2) #2 to 600 MCM

(2) #2 to 600 MCM

(2) #2 to 600 MCM

(2) #2 to 600 MCM

(2) #2 to 600 MCM

(2) #2 to 600 MCM

(2) #2 to 600 MCM

(2) #2 to 600 MCM

(2) #2 to 600 MCM

(2) #2 to 600 MCM

(2) #2 to 600 MCM

(2) #2 to 600 MCM

(2) #2 to 600 MCM

(2) #2 to 600 MCM

(2) #2 to 600 MCM

(2) #2 to 600 MCM

(2) #2 to 600 MCM

(2) #2 to 600 MCM

(2) #2 to 600 MCM

(2) #2 to 600 MCM

(2) #2 to 600 MCM

(2) #2 to 600 MCM

(2) #2 to 600 MCM

(2) #2 to 600 MCM

(2) #2 to 600 MCM

(2) #2 to 600 MCM

(2) #2 to 600 MCM

(2) #2 to 600 MCM

(2) #2 to 600 MCM

(2) #2 to 600 MCM

(2) #2 to 600 MCM

(2) #2 to 600 MCM

(2) #2 to 600 MCM

(2) #2 to 600 MCM

(2) #2 to 600 MCM

(2) #2 to 600 MCM

(2) #2 to 600 MCM

(2) #2 to 600 MCM

(2) #2 to 600 MCM

(2) #2 to 600 MCM

(2) #2 to 600 MCM

(2) #2 to 600 MCM

(2) #2 to 600 MCM

(2) #2 to 600 MCM

(2) #2 to 600 MCM

(2) #2 to 600 MCM

(2) #2 to 600 MCM

(2) #2 to 600 MCM

(2) #2 to 600 MCM

(2) #2 to 600 MCM

(2) #2 to 600 MCM

(2) #2 to 600 MCM

(2) #2 to 600 MCM

(2) #2 to 600 MCM

(2) #2 to 600 MCM

(2) #2 to 600 MCM

(2) #2 to 600 MCM

(2) #2 to 600 MCM

(2) #2 to 600 MCM

(2) #2 to 600 MCM

(2) #2 to 600 MCM

(2) #2 to 600 MCM

(2) #2 to 600 MCM

(2) #2 to 600 MCM

(2) #2 to 600 MCM

(2) #2 to 600 MCM

(2) #2 to 600 MCM

(2) #2 to 600 MCM

(2) #2 to 600 MCM

(2) #2 to 600 MCM

(2) #2 to 600 MCM

(2) #2 to 600 MCM

(2) #2 to 600 MCM

(2) #2 to 600 MCM

(2) #2 to 600 MCM

(2) #2 to 600 MCM

(2) #2 to 600 MCM

(2) #2 to 600 MCM

Page 42 / IM 548

575

208

230

380

460

575

208

230

230

380

460

575

208

230

380

460

380

460

575

460

575

208

230

380

460

575

208

208

230

380

460

575

208

230

380

Table 53. Customer wiring information with multiple point power (300 thru 380)

ALS

UNIT SIZE

300A

315A

330A

340A

360A

370A

380A

VOLTS HZ

60

60

60

60

60

60

60

WIRING TO UNIT POWER BLOCK

POWER BLOCK

TERMINAL SIZE (AMPS)

ELEC CIRC #1 ELEC CIRC #2

840

950

840

840

840

840

950

840

840

840

840

840

840

840

840

840

840

840

840

840

840

840

840

840

840

840

840

840

840

840

840

840

840

840

840

840

950

840

840

840

840

950

840

840

840

840

840

840

840

840

840

840

840

840

840

840

840

840

840

840

840

840

840

840

840

840

840

840

840

840

CONNECTOR WIRE RANGE (COPPER WIRE ONLY)

ELEC CIRC #1

(2) #2 to 600 MCM

(2) #2 to 600 MCM

(2) #2 to 600 MCM

(2) #2 to 600 MCM

(2) #2 to 600 MCM

(2) #2 to 600 MCM

(2) #2 to 600 MCM

(2) #2 to 600 MCM

(2) #2 to 600 MCM

(2) #2 to 600 MCM

(2) #2 to 600 MCM

(2) #2 to 600 MCM

(2) #2 to 600 MCM

(2) #2 to 600 MCM

(2) #2 to 600 MCM

(2) #2 to 600 MCM

(2) #2 to 600 MCM

(2) #2 to 600 MCM

(2) #2 to 600 MCM

(2) #2 to 600 MCM

(2) #2 to 600 MCM

(2) #2 to 600 MCM

(2) #2 to 600 MCM

(2) #2 to 600 MCM

(2) #2 to 600 MCM

(2) #2 to 600 MCM

(2) #2 to 600 MCM

(2) #2 to 600 MCM

(2) #2 to 600 MCM

(2) #2 to 600 MCM

(2) #2 to 600 MCM

(2) #2 to 600 MCM

(2) #2 to 600 MCM

(2) #2 to 600 MCM

(2) #2 to 600 MCM

ELEC CIRC #2

(2) #2 to 600 MCM

(2) #2 to 600 MCM

(2) #2 to 600 MCM

(2) #2 to 600 MCM

(2) #2 to 600 MCM

(2) #2 to 600 MCM

(2) #2 to 600 MCM

(2) #2 to 600 MCM

(2) #2 to 600 MCM

(2) #2 to 600 MCM

(2) #2 to 600 MCM

(2) #2 to 600 MCM

(2) #2 to 600 MCM

(2) #2 to 600 MCM

(2) #2 to 600 MCM

(2) #2 to 600 MCM

(2) #2 to 600 MCM

(2) #2 to 600 MCM

(2) #2 to 600 MCM

(2) #2 to 600 MCM

(2) #2 to 600 MCM

(2) #2 to 600 MCM

(2) #2 to 600 MCM

(2) #2 to 600 MCM

(2) #2 to 600 MCM

(2) #2 to 600 MCM

(2) #2 to 600 MCM

(2) #2 to 600 MCM

(2) #2 to 600 MCM

(2) #2 to 600 MCM

(2) #2 to 600 MCM

(2) #2 to 600 MCM

(2) #2 to 600 MCM

(2) #2 to 600 MCM

(2) #2 to 600 MCM

IM 548 / Page 43

Page 44 / IM 548

Electrical Data Notes

1. Allowable voltage limits:

Unit nameplate 208V/60Hz/3PH: 187V to 229V

Unit nameplate 230V/60Hz/3Ph: 207V to 253V

Unit nameplate 380V/60Hz/3Ph: 342V to 418V

Unit nameplate 460V/60Hz/3Ph: 414V to 506V

Unit nameplate 575V/60Hz/3Ph: 517V to 633V

2. 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 control transformer. Wire size ampacity for separate 115V control circuit power is 15 amps for ALS070A through ALS280A.

3. Compressor RLA values are for wire sizing purposes only but do reflect normal operating current draw at unit rated capacity. If unit is equipped with SpeedTrol condenser fan motors, the first motor on each refrigerant circuit is a single phase, 1 hp motor, with a FLA of 2.8 amps at 460 volts

(5.6 amps at 208/230 volts). If the unit is not equipped with SpeedTrol, the standard fan motor will be 1

1

⁄

2

hp, 3-phase (for ALS070A-280A except ALS204 which will be 2hp, 3-phase) with FLA as shown in the electrical tables. For ALS300A-380A the standard fan motor will be 2 hp, 3-phase.

4. Compressor LRA for reduced inrush start is for the first winding. If the unit is equipped with

SpeedTrol motors, the first motor on each refrigerant circuit is a single phase, 1 hp motor, with a

LRA of 7.3 amps at 460 volts (14.5 amps at 208/230 volts). If the unit is not equipped with

SpeedTrol, the standard fan motor will be 1

1

⁄

2

hp,

3-phase with a LRA as shown in the electrical tables.

5. Single point power supply requires a single disconnect to supply electrical power to the unit. This power must be fused.

6. Multiple point power supply requires two independent power circuits on ALS125A-ALS195A,

ALS300-ALS380 and three independent power circuits on ALS205A-ALS280A each with separate fused disconnects and a separate control circuit.

7. All field wiring to unit power block or optional nonfused disconnect switch must be copper.

8. Field wire size values given in tables apply to 75°C rated wire per NEC except for ALS185A-

ALS204A and ALS370A, ALS380A for 208V application or as noted.

9. Disconnect switches must be field supplied.

10. All wiring must be done in accordance with applicable local and national codes.

11. Recommended time delay fuse size or circuit breakers (Canadian units only) is equal to 150% of the largest compressor-motor RLA plus 100% of remaining compressor RLAs and the sum of condenser fan FLAs.

12. Maximum time delay fuse size or circuit breakers (Canadian units only) is equal to 225% of the largest compressor-motor RLA plus 100% of remaining compressor RLAs and the sum of condenser fan FLAs.

Electrical Legend

Table 51.

AB

RESI,RES2

ADI

CI-C3

CII,C2I

CBI-CB6

CB9

CBIO

CHWI

COMPR I-3

CSII-CS33

CTI,CT2

DS1,DS2

EXV

FI

F2

ALARM BELL

RESISTOR, CURRENT TRANSFORMER

ANALOG DIGITAL INPUT BOARD

SURGE CAPACITOR, COMPRESSOR

CAPACITOR, SPEEDTROL

CIRCUIT BREAKER (POWER)

CIRCUIT BREAKER (MICROTECH)

CIRCUIT BREAKER (FAX ALARM)

CHILLED WATER INTERLOCK

COMPRESSORSI-3

COMPRESSOR SOLENOID

CURRENT TRANSFORMER

DISCONNECT SWITCH, MAIN

ELECTRONIC EXPANSlON VALVE

FUSE, CONTROL CIRCUIT

FUSE, COOLER HEATER

FB5

FB6-FBI5

GDI-GD3

GFP

GRD,GND

HTRI-HTR3

HTR5

JI-JI3

FUSEBLOCK, CONTROL POWER

FUSEBLOCKS, FAN MOTORS

GUARDISTOR RELAY

GROUND FAULT PROTECTOR

GROUND

COMPRESSOR HEATER

HEATER,EVAPORATOR

JUMPERS (LEAD)

JB5

KEYPAD

LPSI-LPS3

MI-M6

JUNCTION BOX, EVAP. HEATER

KEYPAD SWITCH & DISPLAY

LIQUID PRESENCE SENSOR

CONTACTORS, COMPRESSOR

Ml-M37

MCB250

CONTACTOR, FAN MOTORS

MICROTECH CONTROL BOARD-250

MHPRI-MHPR3 MECH. HIGH PRESSURE RELAY

MJ MECHANICAL JUMPER

MODEMI

MODEM2

MPRI-MPR3

MTRJI-MTR37

NB

OB

OLI-OL6

OSI-OS3

PBI-PB3

PSI-PS3

PVMI-PVM3

MODEM, MICROTECH

MODEM, FAX

MOTOR PROTECTOR RELAY

MOTORS, CONDENSER FANS

NEUTRAL BLOCK

OUTPUT BOARD, MICROTECH

OVERLOADS

OIL SAFETY SWITCH

POWER BLOCK, MAIN

PUMPDOWN SWITCHES

PHASE VOLTAGE MONITOR

BACK OR SIDE OF CTRL BOX

CTRL BOX, POWER PANEL

CTRL BOX, CTRL PANEL

CTRL BOX, POWER PANEL

INSIDE SPEEDTROL BOX

CTRL BOX, POWER PANEL

CTRL BOX, CTRL PANEL

CTRL BOX, CTRL PANEL

FIELD INSTALLED

ON BASE RAIL

ON COMPRESSOR

CTRL BOX, POWER PANEL

CTRL BOX, POWER PANEL

CTRL BOX, CTRL PANEL

CTRL BOX, SWITCH PANEL

CTRL BOX, SWITCH PANEL

CTRL BOX, POWER PANEL

CTRL BOX, POWER PANEL

CTRL BOX, CTRL PANEL

CTRL BOX, POWER PANEL

CTRL BOX, POWER PANEL

ON COMPRESSORS

WRAPPED AROUND EVAP.

CTRLBOX, CTRLPANEL

NEAR EVAP, ON BASE RAIL

CTRL BOX, KEYPAD PANEL

ON COMPRESSOR

CTRLBOX, POWERPANEL

CTRL BOX, POWER PANEL

CTRL BOX, CTRL PANEL

CONTROL BOX, CTRL PANEL

CTRL BOX, CTRL PANEL

CTRL BOX, CTRL PANEL

CTRL BOX, CTRL PANEL

CONTROL BOX, CTRL PANEL

CONDENSER SECTION

CTRL BOX, CTRL PANEL

CTRL BOX, CTRL PANEL

CTRL BOX, POWER PANEL

CTRL BOX, CTRL PANEL

CTRL BOX, POWER PANEL

CTRL BOX, SWITCH PANEL

CTRL BOX, POWER

RES1,RES2

SI

RESISTOR, CURRENT TRANSFORMER

SWITCH, MANUAL START/STOP

SCII,SC21,SC31 SPEED CONTROL

SIG.CONV(SC) SIGNAL CONVERTER

SVI,SV2,SV7

SV3,SV4,SV8

SV5,SV6,SV9

TI

T2, T5

T3

SOLENOID VALVE, LIQ. LINES

SOLENOID VALVE, LIQ. INJECTION

SOLENOID VALVE, HG BYPASS

TRANSFORMER, MAIN CONTROL

T4,T6

TIO

CTRL BOX, POWER PANEL-

CTRL BOX, KEYPAD PANEL

INSIDE SPEEDTROL BOX

CTRL BOX, CTRL PANEL

ON LIQUID LINES

ON COMPR LIQ. INJ. LINE

ON LINE TO HOT GAS VALVE

CTRL BOX, POWER PANEL

TRANSFORMER, 120 TO 24V CONTROL CTRL BOX, CTRL PANEL

TRANSFORMER, 575 TO 208-230V CTRL BOX, CTRL PANEL

SPEEDTROL

TRANSFORMER, 24 TO 18V CONTROL

TRANSFORMER, 208-240 TO 24V OR

460 TO 24V -SPEEDTROL

CTRL BOX, CTRL PANEL

CTRL BOX, CTRL PANEL

TB2

TB3

TB4-TB6

TB7

TERMINAL BLOCK, 120V FIELD

TERMINAL BLOCK, 24V FIELD

TERMINAL BLOCK, CONTROL

TERM114AL BLOCK, FIELD CONN.

(LESS THAN 24V ONLY)

CTRL BOX, CTRL PANEL

CTRL BOX, CTRL PANEL

CTRL BOX, CTRL PANEL

CTRL BOX, CTRL PANEL

TB9

TBIO

TD5-TD7

TERMINAL BLOCK, MICROTECH ONLY

TERMINAL BLOCK, FAX ALARM

CTRL BOX, CTRL PANEL

CTRL BOX, CTRL PANEL

TIME DELAY, COMPR. REDUCED INRUSH CTRL BOX, CTRL PANEL

POWER WIRING, FACTORY INSTALLED

POWER WIRING, FACTORY INSTALLED

POWER WIRING, FACTORY INSTALLED

CONTROL BOX TERMINAL, FIELD CONN. USAGE

CONTROL BOX TERMINAL, FACTORY USAGE

UNINDENTIFIED COMPONENT TERMINAL

INDENTIFIED COMPONENT

TERMINAL

WIRE NUT

MANUAL RESET, CONTROL

AUTOMATIC RESET, CONTROL

CABLE-TWISTED.

SHIELDED AND

JACKETED PAIR

OPTION

BLOCK

THERMISTOR

DIODE

CAPACITOR

MOV

V

VARISTOR

Evaporator Freeze Protection

All heat exchangers come equipped with thermostatically controlled heat tape. When power is applied to terminals 13 and 16, the heat tape will provide freeze protection down to

–20°F (–28.8°C). However, this should not be the only method of freeze protection. Unless the evaporator is flushed and drained as is described below in note 4 two or more of the remaining 3 recommendations must be followed as part of the system design:

1. By continuous circulation of water through the piping and the heat exchanger.

2. By the inclusion of glycol solution in the chilled water circuit.

3. By the addition of insulation, and heat during cold weather, to the exposed piping and heat exchanger.

4. By draining and flushing the chiller vessel with glycol during subfreezing weather.

Figure 21 shows typical field wiring that is required for unit installation. On models ALS125A through 380A the time clock is connected between terminals 60 and 61.

It is the responsibility of the installing contractor and/or on-site maintenance personnel to insure that this additional protection is provided. Routine checks should be made to insure adequate freeze protection is maintained.

Failure to do so may result in damage to unit components. Freeze damage is not considered a warranty failure.

IM 548 / Page 45

Page 46 / IM 548

Typical Field Wiring Diagram

Figure 21. ALS125A thru 380A

Disconnect

(by others)

Unit main terminal block

3 phase power supply

Fused control circuit transformer option

Disconnect

(by others)

N

120 VAC control power

10A

fuse

(by others)

Separate evaporator heater power option

120 VAC

(by others)

N

Disconnect

(by others)

10A

fuse

(by others)

24V or 120 VAC

(by others)

N

CHW pump relay

(by others)

4-20 MA for

CHW reset

(by others)

+

–

4-20 MA for demand limit

(by others)

+

–

+

Connection to RS232 for modem or direct

PC connection

–

GND

Connection to RMS

(remote monitoring sequence) or to NMP

(network master panel)

GND

–

+

Time clock

Auto

Off

Remote stop

(by others)

Manual

CHW flow switch

(by others)

Alarm bell option

Factory supplied alarm field wired

Alarm bell max 1.5 amps

GND lug

To compressor(s) and fan motors

TB2

1

540

NB

545

If separate evaporator heater power option is used — remove wires 540 and 545.

13

16

9

10

TB4

50

51

52

45

46

47

48

49

53

54

55

Output relay 1

5A

Solid state relay

24V or 120 VAC

1.5 amps max.

250

Ω

load impedance

GND

250

Ω

load impedance

Inherent in

MicroTech controller

1-CLR (RS232 TR)

3-BLK (RS232 RC)

5-GND

Communication port “A”

3-BLK (RS485)

4-CLR (RS485)

5-GND

Communication port “B”

60

61

MJ

If remote stop control is used, remove jumper from term 60 to 61.

62

63

TB5

102

107

GND

Output relay 0

5A

24 VAC-

35 VA max.

Unit Layout and Principles of Operation

Major Component Locations

Figure 22. Component locations (125A thru 204A)

Cond

Fan

11

Cond

Fan

12

Compr.

No. 1

Cond

Fan

13

Cond

Fan

14

Cond

Fan

15

Cond

Fan

16

Cond

Fan

17

Cond

Fan

21

Cond

Fan

22

Compr.

No. 2

Cond

Fan

23

Cond

Fan

24

Top of Unit

Cond

Fan

25

Cond

Fan

26

Cooler

Cond

Fan

27

Figure 23. Component locations (205A thru 280A)

Condenser Circuit #1 Condenser Circuit #3

Cond

Fan

11

Cond

Fan

21

Cond

Fan

12

Cond

Fan

22

Cond

Fan

13

Cond

Fan

23

Cond

Fan

14

Cond

Fan

24

Cond

Fan

15

Cond

Fan

25

Cond

Fan

16

Cond

Fan

26

Condenser Circuit #2

Inlet

Compr.

#1

Evaporator

3 Refrigerant Circuits

Cond

Fan

31

Cond

Fan

32

Cond

Fan

33

Cond

Fan

34

Cond

Fan

35

Cond

Fan

36

Condenser Circuit #3

Outlet

Compr.

#2

Compr.

#3

Figure 24. Component locations (300A thru 380A)

12 Fans ALS360A-380A

10 Fans ALS300A-340A

Condenser Circuit #1

12 Fans ALS360A-380A

10 Fans ALS300A-340A

Condenser Circuit #3

Cond

Fan

#11

Cond

Fan

#21

Cond

Fan

#12

Cond

Fan

#22

Cond

Fan

#13

Cond

Fan

#23

Cond

Fan

#14

Cond

Fan

#24

Cond

Fan

#15

Cond

Fan

#25

Cond

Fan

#16

Cond

Fan

#26

Condenser Circuit #2

Inlet

Compr.

#1

Compr.

#3

Cond

Fan

#31

Cond

Fan

#41

Cond

Fan

#32

Cond

Fan

#42

Cond

Fan

#33

Cond

Fan

#43

Cond

Fan

#34

Cond

Fan

#44

Cond

Fan

#35

Cond

Fan

#45

Cond

Fan

#36

Cond

Fan

#46

Condenser Circuit #4

Outlet

Evaporator

4 Refrigerant Circuits

Compr.

#2

Compr.

#4

IM 548 / Page 47

Page 48 / IM 548

Control Center

All electrical controls are enclosed in a weather resistant control center with keylocked, hinged access doors. The control center is composed of two separate compartments, high voltage and low voltage. All of the high voltage components are located in the compartment on the right side of the unit.

The low voltage components are located on the left side with the 115 VAC terminals located behind the deadfront panel. This protects service personnel from 115 VAC terminals when accessing the adjustable and resettable controls.

Figure 25. Control center layout (ALS125A thru 204A)

FB

6

FB7 FB8 FB9 FB10 FB11

T1

FB

5

GRD

ADX EXV

Low Voltage Wireway

Keypad

Mech. Relays

F1 CB F2

NB

High Voltage Wireway

T10

M11 M12 M13 M15 M23 M25

M21 M22 M14 M24

CT1

PB1

GFP

S

GFP

R

MCBI ADI

Output

Board

OL5 OL1 OL2 OL6

Low Voltage Wireway

TB4 TB5

Low Voltage Wireway Low Voltage Wireway

GO1 GO2

T4 T2

T8 T7

CB5 CB1 PVM CB2 CB6

Fax Alarm

Option

M5 M1

C1 C2

M2 M6

SC

Figure 26. Control center layout (ALS205A thru 280A)

FB

12

Keypad

FB

13

FB

14

M31 M32 M33 M34 M35

High Voltage Wireway

DB2

FB

6

FB7 FB8 FB9

FB

10

FB

11

EXVB1 EXVB2

ADX D10X

Low Voltage Wireway

Mech. Relays

F1 CB F2

NB

High Voltage Wireway

M11 M12 M13 M15 M23 M25

M21 M22 M14 M24

T10

MCB 280 ADI

OL1

CT1

OL2

OB1

CT2

T1

CT3

FB

5

GRD

PB1

OL3

Low Voltage Wireway

TB4 TB5

Low Voltage Wireway

CB1 CB2 CB3

SC1 SC2 SC3

Low Voltage Wireway

GD

R1

GD

R2

TB4 TB2

TB7

GD

R3

TB8

TB6

M1 M2 M3

Figure 27. Control center layout (ALS300A thru 380A)

IM 548 / Page 49

Page 50 / IM 548

Sequence of Operation

The following sequence of operation is typical for McQuay models ALS125A through ALS380A screw water chillers. The sequence may vary depending on the software revision or various options which may be installed on the chiller.

Off conditions

With power supplied to the unit, 115 VAC power is applied through the control fuse F1 to the compressor heaters (HTR1, HTR2, HTR3 and evaporator heater) and the primary of the 24V control circuit transformer. Note: Compressor heaters must be on for at least 12 hours prior to start-up. The

24V transformer provides power to the MicroTech controller and related components. With 24V power applied, the controller will check the position of the front panel system switch. If the switch is in the

“stop” position the chiller will remain off and the display will indicate the operating mode to be OFF:

System Sw. The controller will then check the pumpdown switches. If any of the switches is in the

“stop” position, that circuit’s operating mode will be displayed as OFF: PumpDwnSw. If the switches for both circuits are in the “Stop” position the unit status will display OFF: PumpdownSw’s. If the remote start/stop switch is open, the chiller will be OFF: RemoteSw. The chiller may also be commanded off via communications from a separate communicating panel such as the Remote

Monitoring and Sequencing Panel or an Open Protocol interface. The display will show OFF:

RemoteComm if this operating mode is in effect. If an alarm condition exists which prevents normal

operation of both refrigerant circuits, the chiller will be disabled and the display will indicate OFF:

Alarm. If the control mode on the keypad is set to “Manual Unit Off,” the chiller will be disabled and

the unit status will display OFF: ManualMode. Assuming none of the above stop conditions are true, the controller will examine the internal time schedule to determine whether the chiller should be permitted to start. The operating mode will be OFF: TimeClock if the time schedule indicates time remaining in an “off” time period.

Alarm

The alarm light on the front panel will be illuminated when one or more of the cooling circuits has an active alarm condition which results in the circuit being locked out of operation. Unless the alarm condition affects all circuits the remaining circuits will operate as required. Refer to IM 549 for additional details.

Start-up

If none of the above “off” conditions are true, the MicroTech controller will initiate a start sequence and energize the chilled water pump output relay. The chiller will remain in the WaitForFlow mode until the field installed flow switch indicates the presence of chilled water flow. If flow is not proven within

30 seconds, the alarm output will be turned on, the keypad display will be WaitForFlow and the chiller will continue to wait for proof of chilled water flow. Once flow is established, the controller will sample the chilled water temperature and compare it against the Leaving Chilled Water Set Point, the Control

Band, and the Start-up Delta Temperature, which have been programmed into the controller’s memory.

If the leaving chilled water temperature is above the Leaving Chilled Water Set Point plus

1

⁄

2

the Control

Band plus the adjustable Start-up Delta Temperature, the controller will select the refrigerant circuit with the lowest number of starts as the lead circuit and energize the first stage of the Cool Staging mode. The controller will start the compressor and energize the compressor liquid injection solenoid along with the main liquid line solenoid. The controller will delay the opening of the electronic expansion valve until the evaporator pressure decreases to a preset value. This is the evaporator prepurge mode and the display will show Pre-Purge. The valve will then open allowing refrigerant to flow through the expansion valve and into the evaporator and the display will show Opened EXV. If additional cooling capacity is required, the controller will energize the additional cooling capacity by activating the first compressor’s capacity control solenoids. As the system load increases, the controller will start the lag refrigerant circuit in the same manner after interstage timers are satisfied. The compressors and capacity control solenoids will automatically be controlled as required to meet the cooling needs of the system. The electronic expansion valves are operated by the MicroTech controller to maintain precise refrigerant control to the evaporator at all conditions.

Condenser control

The first condenser fan stage will be started along with the first compressor to provide initial condenser head pressure control. The MicroTech controller will activate the remaining condenser fans as needed to maintain proper condenser pressure. The MicroTech controller continuously monitors the condenser minus evaporator lift pressure and will adjust the number of operating condenser fans as required. The number of condenser fans operating will vary with outdoor temperature and system load. The

condenser fans are matched to the operating compressors so that when a compressor is off all fans for that circuit will also be off. On units with the fan speed control option (SpeedTrol) the lead fan on each circuit will vary in speed to maintain condenser pressure at lower outdoor temperatures.

Pumpdown

As the system chilled water requirements diminish, the compressors will be unloaded. As the system load continues to drop, the electronic expansion valves will be stepped closed and the refrigerant circuits will go through a pumpdown sequence. As the evaporator pressure falls below the pumpdown pressure set point while pumping down, the compressor(s) and condenser fans will stop. The unit has a one time pumpdown control logic; therefore, if the evaporator pressure rises while the refrigerant circuit is in a pumpdown mode, the controller will not initiate another pumpdown sequence. The controller will keep the unit off until a call for cooling occurs. Refer to the pumpdown control section in IM 549 for additional details. The chilled water pump output relay will remain energized until the time schedule’s “on” time expires, the remote stop switch is opened, the system switch is moved to the stop position, or a separate communications panel such as the Remote Monitoring and Sequencing

Panel or an Open Protocol interface deactivates the chilled water pump output.

Refrigerant Piping Schematic

Figure 28.

Discharge line

Shut-off

valve

Compressor Envelope

Gas return thru motor

Economizer

Screw Motor

Air cooled condenser coil

Liquid injection

Suction line

Regulator

valve

Shut-off valve

Replaceable core

filter-drier

Solenoid

valve

Shut-off valve

Electronic expansion valve

Liquid line

solenoid

valve

DX Evaporator

IM 548 / Page 51

Page 52 / IM 548

Start-up and Shutdown

Pre Start-up

To assure correct compressor rotation, field power supply leads must be properly phased prior to startup.

1. With all electric disconnects open, check all screw or lug type electrical connections to be sure they are tight for good electrical contact.

2. Inspect all water piping for flow direction and correct connections at the evaporator.

3. Using a phase tester, check that electrical phasing to each compressor circuit is A-B-C for phases L1,

L2, & L3 respectively.

4. Check the voltage of the unit power supply and see that it is within the ±10% tolerance that is allowed. Voltage unbalance between phases must be within ±3%.

5. Check the unit power supply wiring for adequate ampacity and a minimum insulation temperature rating of 75°C.

6. Verify that all mechanical and electrical inspections have been completed per local codes.

7. See that all auxiliary control equipment is operative and that an adequate cooling load is available for initial start-up.

8. Check all compressor valve connections for tightness to avoid refrigerant loss at start-up. Although all factory connections are tight before shipment, some loosening may have resulted from shipping vibration. Open the compressor suction and discharge shutoff valves until backseated. Open the liquid line shutoff valves until backseated. Always replace valve seal caps.

9. Make sure system switch S1 is in the “Stop” position and pumpdown switches PS1, PS2, PS3 and

PS4 are set to “Pumpdown and Stop,” throw the main power and control disconnect switches to

“on.” This will energize crankcase heaters. Wait a minimum of 12 hours before starting up unit.

Turn compressor circuit breakers to “off” position until ready to start unit.

10. Vent the air from the evaporator as well as from the system piping. Open all water flow valves and start the chilled water pump. Check all piping for leaks. Flush the evaporator and system piping to obtain clean, noncorrosive water in the evaporator circuit.

Most relays and terminals in the unit control center are powered when S1 is closed and the control circuit disconnect is on. Therefore do not close S1 until ready for start-up.

Initial start-up must be performed by McQuayService personnel. Don’t proceed with start-up until IM549 has been read.

Start-up

1. Double check that the compressor suction and discharge shutoff valves are backseated. Always replace valve seal caps.

2. Insure that the ball valves are open on the lines entering the evaporator.

3. Insure that the manual liquid line shutoff valve at the outlet of the subcooler is open.

4. Adjust the leaving chilled water temperature set point on the MicroTech controller to the desired chilled water temperature. The control band is preset for 10 degrees Delta-T between the entering and leaving evaporator water temperature at full load. If the Delta-T is outside an 8°-12°F range, at full load, reset the control band as per the instructions found in the MicroTech IM Manual 549.

5. Start the auxiliary equipment for the installation by turning on the time clock, and/or remote on/off switch, and chilled water pump.

6. Check to see that pumpdown switches PS1, PS2, PS3 and PS4 are in the “Pumpdown and Stop”

(open) position. Throw the S1 switch to the “auto” position.

7. Under the “Control Mode” menu of the keypad place the unit into the automatic cool mode.

8. Start the system by moving pumpdown switch PS1 to the “auto” position.

9. After running circuit 1 for a short time, check the rotation of the condenser fans. (Proper rotation

will have air being drawn into the vertical coils and discharged out the top of the unit.) Check for flashing in the refrigerant sightglass under stable conditions.

10. Repeat steps 8 and 9 for PS2, PS3 and PS4 and the second, third and fourth refrigerant circuits.

11. Superheat is factory adjusted to maintain between 6° and 12°F.

The superheat should be between 6° and 12°F, with the liquid line sightglass full, once the system temperatures have stabilized at the MicroTech set point temperatures.

12. After system performance has stabilized, it is necessary that the “Compressor Equipment Warranty

Form” be completed to obtain full warranty benefits. This form is shipped with the unit, and after completion, should be returned to McQuayService through your sales representative.

Temporary Shutdown

Move pumpdown switches PS1, PS2, PS3 and PS4 to the “Pumpdown and Stop” position. After the compressors have pumped down, turn off the chilled water pump. Caution: Do not turn the unit off

using the “S1” switch, without first moving PS1, PS2, PS3 and PS4 to the “Stop” position, unless it is an emergency as this will prevent the unit from going through a pumpdown.

IMPORTANT

The unit has one time pumpdown operation. When

PS1, PS2, PS3 and PS4 are in the “Pumpdown and

Stop” position the unit will pumpdown once and not run again until the PS1, PS2, PS3 and PS4 switches are moved to the auto position. If PS1, PS2, PS3 and

PS4 are in the auto position and the load has been satisfied the unit will go into one time pumpdown and will remain off until MicroTech senses a call for cooling and starts the unit.

The unit must not be cycled off by using the evaporator pump or the disconnect switch.

It is important that the water flow to the unit is not interrupted before the compressors pumpdown to avoid freeze-up in the evaporator.

If all power is turned off to the unit the compressor heaters will become inoperable. Once power is resumed to the unit it is important that the compressor heaters are energized a minimum of 12 hours before attempting to start the unit. Failure to do so could damage the compressors due to excessive accumulation of liquid in the compressor.

Start-up After Temporary Shutdown

Insure that the compressor heaters have been energized for at least 12 hours prior to starting the unit.

2. Start the chilled water pump.

3. With System switch S1 in the “on” position, move pumpdown switches PS1, PS2, PS3 and PS4 to the “auto” position.

4. Observe the unit operation until the system has stabilized.

IM 548 / Page 53

Page 54 / IM 548

If shutdown occurs or will continue through periods below freezing ambient temperatures, protect the chiller vessel from freezing.

Extended Shutdown

1. Move the PS1, PS2, PS3 and PS4 switches to the manual pumpdown position.

2. After the compressors have pumped down, turn off the chilled water pump.

3. Turn off all power to the unit and to the chilled water pump.

4. Move the emergency stop switch S1 to the “off” position.

5. Close the compressor suction and discharge valves as well as the liquid line shutoff valves.

6. Tag all opened disconnect switches to warn against start-up before opening the compressor suction and discharge valves and liquid line shutoff valves.

7. If glycol is not used in the system drain all water from the unit evaporator and chilled water piping if the unit is to be shut down during winter. Do not leave the vessels or piping open to the

atmosphere over the shutdown period.

8. Leave power applied to the cooler heating cable if a separate disconnect is used.

System Maintenance

General

On initial start-up and periodically during operation, it will be necessary to perform certain routine service checks. Among these are checking the liquid line sightglasses and taking condensing and suction pressure readings. Through the MicroTech keypad, check to see that the unit has normal superheat and subcooling readings.

A Periodic Maintenance Log is located on page 67 of this manual. It is suggested that the report be completed on a monthly basis. The log will serve as a useful tool for a service technician in the event service is required.

Compressor Maintenance

Since the compressor is semi-hermetic requiring no oil separator, oil heaters and pumps, no yearly maintenance is normally required. However, vibration is an excellent check for proper mechanical operation. Compressor vibration is an indicator of the requirement for maintenance and contributes to a decrease in unit performance and efficiency. It is recommended that the compressor be checked with a vibration analyzer at or shortly after start-up and again on an annual basis. When performing the test the load should be maintained as closely as possible to the load of the original test. The vibration analyzer test provides a fingerprint of the compressor and when performed routinely can give a warning of impending problems. The compressor is checked at the factory for maximum vibration of 0.14 IPS (3.56 mm/s) at

3600 rpm.

The compressor is supplied with a lifetime oil filter. It is a good policy to replace this filter anytime the compressor is opened for servicing.

Fan Motor Bearings

The fan motor bearings are of the permanently lubricated type. No lubrication is required. Excessive fan motor bearing noise is an indication of a potential bearing failure.

Electrical Terminals

Electric shock hazard. Turn off all power before continuing with following service.

All power electrical terminals, for compressors and fan motor power wiring, should be retightened every six months, as they tend to loosen in service due to normal heating and cooling of the wire.

Condensers

Condensers are air cooled and constructed with

3

/

8

" (9.5mm) O.D. internally finned copper tubes bonded in a staggered pattern into slit aluminum fins. No maintenance is ordinarily required except the occasional removal of dirt and debris from the outside surface of the fins. McQuay recommends the use of foaming coil cleaners available at air conditioning supply outlets. Use caution when applying such cleaners as they may contain potentially harmful chemicals. Care should be taken not to damage the fins during cleaning. If the service technician has reason to believe that the refrigerant circuit contains noncondensables, manual purging may be required. The purge Shrader valve is located on the vertical coil header on both sides of the unit at the control box end of the coil. Access panels are located at the end of the condenser coil directly behind the control panel. Purge with the unit off, after shutdown of

15 minutes or longer, to allow air to collect at the top of the coil. Restart and run the unit for a brief period. If necessary shut unit off and repeat the procedure. Follow accepted environmentally sound practices when removing refrigerant from the unit.

Refrigerant Sightglass

The refrigerant sightglasses should be observed periodically. (A weekly observation should be adequate.) A clear glass of liquid indicates that there is adequate refrigerant charge in the system to insure proper feed through the expansion valve. Bubbling refrigerant in the sightglass, during stable run conditions, indicates that the system may be short of refrigerant charge. Refrigerant gas flashing in the sightglass could also indicate an excessive pressure drop in the liquid line, possibly due to a clogged filter-drier or a restriction elsewhere in the liquid line. If subcooling is low add charge to clear the sightglass. If subcooling is normal (10°-15°F) and flashing is visible in the sightglass check the pressure drop across the filter-drier.

An element inside the sightglass indicates the moisture condition corresponding to a given element color. If the sightglass does not indicate a dry condition after about 12 hours of operation, the unit should be pumped down and the filter-driers changed.

Lead-Lag

A feature on all McQuay ALS air cooled chillers is a system for alternating the sequence in which the compressors start to balance the number of starts and run hours. Lead-Lag of the refrigerant circuits is accomplished automatically through the MicroTech Controller. When in the auto mode the circuit with the fewest number of starts will be started first. If all circuits are operating and a stage down to one circuit is required, the circuit with the most operating hours will cycle off first. The operator may override the

MicroTech controller, and manually select the lead circuit as circuit #1, #2, #3 or circuit #4.

Service

Service on this equipment is to be performed by qualified refrigeration personnel familiar with equipment operation, maintenance, correct servicing procedures, and the safety hazards inherent to this work. Causes for repeated tripping of safety controls must be investigated and corrected.

Disconnect all power before doing any service inside the unit.

NOTICE

Anyone servicing this equipment shall comply with the requirements set forth by the EPA in regards to refrigerant reclamation and venting.

IM 548 / Page 55

Page 56 / IM 548

Compressor Solenoids

The ALS unit screw compressors are equipped with 3 solenoids to control compressor unloading. The solenoids are controlled by MicroTech outputs. See unit wiring diagrams. The solenoids are energized at various compressor load conditions as indicated in the table below.

Table 54.

COMPRESSOR

LOADING %

100 %

75 %

50 %

25 %

COMPRESSOR UNLOADING SOLENOID STATUS

TOP

SOLENOID

Energized

Energized

Off

Off

BOTTOM FRONT BOTTOM REAR

SOLENOID

Off

Energized

Off

Energized

SOLENOID

Energized

Off

Energized

Off

Location of the solenoids is as follows:

The top solenoid is on top of the compressor near the discharge end.

The bottom solenoids are on the lower side of the compressor on the opposite side from the terminal box. The bottom front solenoid is the one closest to the discharge end of the compressor. The bottom rear solenoid is the one closest to the motor end of the compressor.

If the compressor is not loading properly check the solenoids to see if they are energized per the above chart. A complete check will include a check of the MicroTech output, the wiring to the solenoid and the solenoid coil itself.

Filter-Driers

A replacement of the filter-drier is recommended during scheduled service maintenance of the unit, any time excessive pressure drop is read across the filter-drier and/or when bubbles occur in the sightglass with normal subcooling. A partially clogged filter can also cause trips on the no liquid run sensor. The

maximum recommended pressure drops across the filter-drier are as follows:

Table 55. Filter drier pressure drop

PERCENT CIRCUIT

LOADING (%)

100%

75%

50%

25%

MAXIMUM RECOMMENDED PRESSURE

DROP ACROSS FILTER DRIER PSIG (KPA)

10 (69)

8 (55.2)

5 (34.5)

4 (27.6)

The filter-drier should also be changed if the moisture indicating liquid line sightglass indicates excess moisture by the wet system color indicators.

During the first few months of operation the filter-drier replacement may be necessary if the pressure drop across the filter-drier exceeds the values listed in the paragraph above. Any residual particles from the unit heat transfer tubing, compressor and miscellaneous components are swept by the refrigerant into the liquid line and are caught by the filter-drier.

The following is the procedure for changing the filter-drier core:

This procedure is slightly different from a typical reciprocating compressor unit due to the use of a liquid injection feature on the ALS screw compressor unit. Anytime the compressor contactor is closed liquid from the liquid line is injected into the screw for cooling and sealing. This liquid injection also occurs during normal pumpdown and limits how low a pumpdown can be achieved.

The standard unit pumpdown is set to stop pumpdown when 34 psig (235 kPa) suction pressure is reached. To fully pump down a circuit beyond 34 psig (235 kPa) for service purposes a “Full

Pumpdown” service mode can be activated using the keypad. Go to the “Alarm Spts” Menu on the

MicroTech keypad, step through the menu items until “FullPumpDwn” is displayed. Change the setting from “No” to “Yes”.

The next time either circuit is pumped down, the pumpdown will continue until the evaporator pressure reaches 2 psig (14 kPa) or 60 seconds have elapsed, whichever occurs first. Upon completing the pumpdown, the “FullPumpDwn” set point is automatically changed back to “No”.

The procedure to perform a full service pumpdown for changing the filter-drier core is as follows.

1. Perform a normal pumpdown to 34 psig (235 kPa) by moving the pumpdown switch to the

“Pumpdown” position. This step will pump down the evaporator with compressor liquid injection still active.

2. Close the liquid line shutoff valve above the filter-drier, on the circuit to be serviced.

3. Under the “Alarm Spts”, change the “FullPumpDwn” set point from “No” to “Yes”.

4. The circuit status should be “Off:PumpDwnSw”. Move the circuit pumpdown switch from

“Pumpdown and Stop” to “Auto”. Also clear the anticycle timers through the MicroTech keypad.

5. The compressor should pump down the circuit until the evaporator pressure reaches 2 psig (14 kPa) or 60 seconds has elapsed, whichever occurs first.

6. Upon completing the full pumpdown per step 5, the “FullPumpDwn” set point is automatically changed back to “No” which reverts back to standard 34 psig (235 kPa) stop pumpdown pressure.

7. If the pumpdown does not go to 2 psig (14 kPa) on the first attempt, one more attempt can be made by repeating steps 3, 4 and 5 above. Do not repeat “FullPumpDwn” more than once to avoid

excessive screw temperature rise under this abnormal condition. A no liquid start alarm and shutdown may occur during this procedure. Proceed as noted in step number 8.

8. The circuit is now in the deepest pumpdown which can safely be achieved by the use of the compressor. Any remaining refrigerant must be removed from the circuit by the use of a refrigerant recovery unit.

Remove and replace the filter-drier(s). If the refrigerant circuit is opened for more than 10 minutes evacuate the lines through the liquid line manual shutoff valve(s) to remove noncondensables that may have entered during filter replacement. A leak check is recommended before returning the unit to operation.

Liquid Line Solenoid Valve

The liquid line solenoid valves that shuts off refrigerant flow in the event of a power failure, do not normally require any maintenance. (The electronic expansion valve, on a sudden power failure, remains

open to the position it was at when the power failure occurred. During normal operation the EEV closes for

automatic pumpdown and the liquid line solenoid valve closes only when the compressor stops.) They may, however, require replacement of the solenoid coil or of the entire valve assembly.

The solenoid coil can be checked to see that the stem is magnetized when energized by touching a screwdriver to the top of the stem. If there is no magnetization either the coil is bad or there is no power to the coil.

The solenoid coil may be removed from the valve body without opening the refrigerant piping after first moving pumpdown switches PS1, PS2 and PS3 to the “manual pumpdown” position and opening the S1 switch. For personal safety shut off and lock out the unit power.

The coil can then be removed from the valve body by simply removing a nut or snap-ring located at the top of the coil. The coil can then be slipped off its mounting stud for replacement. Be sure to replace the coil on its mounting stud before returning pumpdown switches PS1, PS2 and PS3 to the “auto pumpdown” position.

To replace the entire solenoid valve follow the steps involved when changing a filter-drier.

Liquid Injection Solenoid Valve

Liquid injection is required during compressor operation to seal and cool the screw. A liquid injection sensor is installed on the compressor to assure that liquid injection occurs whenever the compressor is running. A failure of the liquid injection solenoid valve to open will cause the compressor to shut down due to lack of liquid injection.

The liquid injection solenoid valve, like the liquid line solenoid valve, only closes when the compressor stops. Since this valve is open during pumpdown the refrigerant in the line will cause the suction pressure to rise 10 to 20 psig (69 to 138 kPa) after shutdown occurs. The solenoid coil and valve body can be removed as in the same procedure as the liquid line solenoid valve but it is important that the S1 switch be opened first.

IM 548 / Page 57

Electronic Expansion Valve

The electronic expansion valve is located adjacent to the compressor. The refrigerant is piped so it first passes through the electronic expansion valve, then through the motor housing cooling the motor, before going into the evaporator. Refer to the Refrigerant Piping Schematic found on page 46.

The expansion valve is responsible for allowing the proper amount of refrigerant to enter the evaporator to match the cooling load. It does this by maintaining a constant superheat. (Superheat is the difference

between refrigerant temperature of the vapor as it leaves the evaporator and the saturation temperature

corresponding to the evaporator pressure.) All ALS chillers are factory set for between 8°F (4.5°C) and 12°F

(6.6°C) superheat at 75% to 100% load and between 6°F (3.3°C) and 10°F (5.6°C) below 75% load. The superheat is controlled by the microprocessor and is not adjustable.

The expansion valve, like the solenoid valve, should not normally require maintenance, but if it requires replacement, the unit must be pumped down by following the steps involved when changing a filterdrier.

If the problem can be traced to the electric motor only, it can be unscrewed from the valve body without removing the valve but only after pumping the unit down. Disassemble valve at the brass hex nut. Do no disassemble valve at the aluminum housing.

Figure 29. Electronic expansion valve

Page 58 / IM 548

Raintight Flex

Connector

Motor

(Aluminum Housing)

Drive Coupling

Pushrod

Extended Copper

Fittings

FLOW g

Stops

Bonnet

Valve Body (Brass)

Piston

Bottom

Spring

Figure 30. Top view of typical dual circuit shell and tube evaporator

Liquid Connections

Water Baffles

Suction

Connections

Refrigerant Tubes

Shell

Water Nozzles

Tube Sheets

Head Rings

Covers

Electronic Expansion Valve Operation

There are 3 colored indicator LEDs (green, red, yellow) located in the control panel on the electronic expansion valve (EXV) board. When the control panel is first powered the microprocessor will automatically step the valve to the fully closed (shut) position and the indicator lights on the EXV will blink in sequence. The valve can also be heard closing as it goes through the steps. The valve will take approximately 14 seconds to go from a full open position to a full closed position.

The position of the valve can be viewed at any time by using the MicroTech keypad through the circuit pressures menus. There are a total of 760 steps between closed and full open.

A feature of the electronic expansion valve is a maximum operating pressure setting (MOP). This setting limits the load on the compressor during start-up periods where high return evaporator water temperatures may be present. The valve will limit the maximum suction pressure at start-up to approximately 85 psig (586 kPa). The valve will close to a point necessary to maintain the 85 psig (586

kPa). During this time the superheat will rise above 12°F (6.6°C) and not drop below 12°F (6.6°C) until the suction pressure drops below 85 psig (586 kPa). The valve will maintain evaporator pressure close to 85 psig (586 kPa) until the evaporator water temperature decreases to approximately 55 to 60°F

(12.7 to 15.6°C).

When the circuit starts the valve opens as soon as the evaporator pressure decreases to 40 psig (275 kPa).

At the end of the cooling cycle the valve closes to cause the system to pump down. The valve closes at the rate of approximately 55 steps per second, or from full open to full closed in approximately 14 seconds. The valve closing during pumpdown will occur in approximately 20-30 seconds after the pumpdown switch is moved to the “Pumpdown and Stop” position.

Evaporator

The evaporator is of the direct expansion, shell-and-tube type with refrigerant flowing through the tubes and water flowing through the shell over the tubes. The tubes are internally finned to provide extended surface as well as turbulent flow of refrigeration through the tubes. Normally no service work is required on the evaporator. There may be instances where a tube will leak refrigerant into the water side of the system. In the cases where only one or two tubes leak, the problem can best be solved by plugging the tube at both ends. When the tube must be replaced, the old tube can be removed and replaced. Follow

the requirements set forth by the EPA for the pumpdown and recovery of refrigerant.

To remove a tube, the unit should be temporarily pumped down. Follow the steps involved when changing a filter-drier. These steps will insure a minimum amount of refrigerant loss when the evaporator is opened up. The tubes are mechanically expanded into the tube sheets at each end of the evaporator. In order to remove the tubes, it is necessary to break this bond by collapsing the tube. After doing this at both ends of the shell, the tube can be removed for replacement. The new tube can then be inserted and re-expanded into the tube sheet.

Note: The bond produced by expansion must be refrigerant tight. This bond must be produced by

applying Locktite (red) to the tube and rolling it into the tube sheet.

After reassembling the evaporator, a small amount of refrigerant should be introduced by momentarily opening the manual liquid line valve. A leak check should then be performed on the evaporator.

Tube removal can only take place after the leaking tube is located. One method that would work would be to subject each tube to air pressure by plugging each end and, with a pressure gauge attached to one of the end plugs, observing if there is a loss of air pressure over a period of a minute or two.

Another method is to place a cork plug in each tube on both ends of the cooler and applying pressure to the shell of the cooler. After a period of time the pressure will leak from the shell into the leaking tube or tubes and pop out the cork plug.

Refrigerant Charging

ALS air cooled screw chillers are shipped factory charged with a full operating charge of refrigerant but there may be times that a unit must be recharged at the jobsite. Follow these recommendations when field charging. Refer to the unit operating charge found in the physical data tables on pages 17-20.

ALS air cooled screw chillers are more sensitive to undercharging than to overcharging therefore it is preferable to be slightly overcharged rather than undercharged on a circuit. The optimum charge is the charge which allows the unit to run with a solid stream of liquid in the liquid line at all operating conditions. When the liquid line temperature does not drop with the addition of 5-10 lbs of charge then the subcooler is nearly full and proper charge has been reached. If the liquid line temperature does

IM 548 / Page 59

Page 60 / IM 548 not drop and the discharge pressure goes up 3-5 psig (20.7-34.5 kPa) as 5-10 lbs of refrigerant is added the correct maximum charge has been reached.

Unit charging can be done at any steady load condition, at any outdoor ambient temperature. Unit must be allowed to run 5 minutes or longer so that the condenser fan staging is stabilized at normal operating discharge pressure. For best results charge with 2 or more condenser fans operating per refrigerant circuit.

The ALS units have a condenser coil design with approximately 15% of the coil tubes located in a subcooler section of the coil to obtain liquid cooling to within 5°F (3°C) of the outdoor air temperature when all condenser fans are operating. This is equal to about 15-20°F (8.3-11.1°C) subcooling below saturated condensing temperature when pressure is read at the liquid valve between the condenser coil and the liquid line filter drier. Once the subcooler is filled extra charge will not lower the liquid temperature and does not help system capacity or efficiency. However, a little extra (10-15 lbs) will make the system less sensitive.

Note: As the unit changes load or fans cycle on or off, the subcooling will vary but should recover

within several minutes and should never show below 6°F (3.3°C) subcooling at any steady state run condition. Subcooling will vary somewhat with evaporator leaving water temperature and suction superheat. As the evaporator superheat goes lower the subcooling will drop slightly.

Excessive refrigerant losses can also leak oil from the system. When adding charge, if there is visible evidence of a significant oil leakage, add an additional oil charge equivalent to 0.04 pints x the lbs. of refrigerant charge required. (Example: For every 10 lbs. of refrigerant charge add .4 pints of oil.)

A leak in the unit could be very small and have little effect on system operation or could be severe enough to cause the unit to shut down on a safety trip.

One of the following three scenarios will be experienced with an undercharged unit:

1. If the unit is slightly undercharged the unit will show bubbles in the sightglass. Recharge the unit as described in the charging procedure below.

2. If the unit is moderately undercharged the unit will most likely trip on freeze protection. Recharge the unit as described in the charging procedure below.

3. If the unit is severely undercharged the unit will trip off due to lack of liquid injection. In this case either remove the remaining charge by means of a proper reclamation system and recharge the unit with the proper amount of refrigerant as is stamped on the unit nameplate, or add refrigerant through the suction valve on the compressor. Feed liquid into the suction valve when the compressor is running. If the unit is severely undercharged the unit may nuisance trip during this charging procedure. If this happens close off the refrigerant from the tank and restart the unit. Once the unit has enough charge so that it does not trip out continue with step 2 of the charging procedure below.

Procedure to charge a moderately undercharged ALS unit:

1. If a unit is low on refrigerant you must first determine the cause before attempting to recharge the unit. Locate and repair any refrigerant leak. Evidence of oil is a good indicator of leakage however, oil may not be visible at all leaks. Liquid leak detector fluids work well to show bubbles at medium size leaks but electronic leak detectors may be needed to locate small leaks.

2. Add the charge to the system through the suction shutoff valve or through the schrader fitting on the tube entering the evaporator between the compressor and the evaporator head.

3. The charge can be added at any load condition between 25-100% load per circuit but at least 2 fans should be operating per refrigerant circuit if possible. The suction superheat should be in the 6°-12°F

(3.3-6.6°C) range.

4. Add sufficient charge to clear the liquid line sight glass and until all flashing stops in the sightglass.

Add an extra 15-20 lbs. of reserve to fill the subcooler if the compressor is operating at 50-100% load.

5. Check the unit subcooling value on the MicroTech display or by reading the liquid line pressure and temperature at the liquid line near the filter-drier. The subcooling values should be between 6°-20°F

(6.6-11.1°C). The subcooling values will be highest at 75-100% load, approximately 12°-20°F (6.6-

11.1°C) and lowest at 50% load, approximately 6°-12°F (3.3-6.6°C).

6. With outdoor temperatures above 60°F (15.6°C) all condenser fans should be operating and the liquid line temperature should be within 5°-10°F (2.8-5.6°C) of outdoor air temperature. At 25-50% load the liquid line temperature should be within 5°F (2.8°C) of outdoor air temperature with all fans on. At 75-100% load the liquid line temperature should be within 10°F (5.6°C) of outdoor air temperature with all fans on.

7. Overcharging of refrigerant will raise the compressor discharge pressure due to filling of the condenser tubes with excess refrigerant after the liquid line temperature has reached its minimum value.

In-Warranty Return Material Procedure

Compressor

The McQuay International warranty provides for repair or replacement, at the Company’s option, of components supplied by it that may fail within the warranty period. Screw type compressors fall into this category.

In the event of a failure contact the nearest McQuayService office for assistance. During the first year’s installation period, warranty labor and parts will be furnished by McQuayService at no charge (excludes

export) if the failure is determined to be a defect in material or workmanship within McQuay

International control.

ALS units purchased with a four year extended compressor warranty may or may not include extended period warranty labor depending upon the initial purchase agreement. In either event McQuayService should be contacted to handle the repair or replacement of the compressor.

Components Other Than Compressors

Material may not be returned except by permission of authorized factory service personnel of

McQuay International at Minneapolis, Minnesota. A “return goods” tag will be sent to be included with the returned material. Enter the information as called for on the tag in order to expedite handling at our factories and prompt issuance of credits.

The return of the part does not constitute an order for replacement. Therefore, a purchase order must be entered through your nearest McQuay representative. The order should include part name, part number, model number and serial number of the unit involved.

Following our personal inspection of the returned part, and if it is determined that the failure is due to faulty material or workmanship, and in warranty, credit will be issued on customer’s purchase order.

All parts shall be returned to the pre-designated McQuay factory transportation charges prepaid.

Appendix

Standard Controls

Thermistor sensors

Note: Refer to IM 549 for a more complete description of the controls application, settings,

adjustments, and checkout procedures.

All sensors are premounted and connected to the MicroTech field wiring strip with shielded cable. A description of each sensor is listed here. For location of each sensor refer to Figures 31, 32 and 33.

Evaporator leaving water temperature — This sensor is located on the evaporator water outlet connection and is used for capacity control of the chiller and low water temperature freeze protection.

Evaporator entering water temperature — This sensor is located on the evaporator water inlet connection and is used for monitoring purposes and return water temperature control.

Evaporator pressure transducer circuit # 1 — This sensor is located on the suction side of compressor # 1 and is used to determine saturated suction refrigerant pressure and temperature. It also provides low pressure freeze protection for circuit # 1.

Evaporator pressure transducer circuit # 2 — This sensor is located on the suction side of compressor #

2 and is used to determine saturated suction refrigerant pressure and temperature. It also provides low pressure freeze protection for circuit # 2.

Evaporator pressure transducer circuit # 3 — This sensor is located on the suction side of compressor # 3 and is used to determine saturated suction refrigerant pressure and temperature. It also provides low pressure freeze protection for circuit # 3.

Evaporator pressure transducer circuit # 4 — This sensor is located on the suction side of compressor # 4 and is used to determine saturated suction refrigerant pressure and temperature. It also provides low pressure freeze protection for circuit # 4.

IM 548 / Page 61

Page 62 / IM 548

Condenser pressure transducer circuit # 1 — The sensor is located on the discharge of compressor # 1 and is used to read saturated refrigerant pressure and temperature. The transducer will unload the compressor should a rise in head pressure occur which is outside the MicroTech set point limits. The signal is also used in the calculation of circuit #1 subcooling.

Condenser pressure transducer circuit # 2 — The sensor is located on the discharge of compressor # 2 and is used to read saturated refrigerant pressure and temperature. The transducer will unload the compressor should a rise in head pressure occur which is outside the MicroTech set point limits. The signal is also used in the calculation of circuit #2 subcooling.

Condenser pressure transducer circuit # 3 — The sensor is located on the discharge of compressor # 3 and is used to read saturated refrigerant pressure and temperature. The transducer will unload the compressor should a rise in head pressure occur which is outside the MicroTech set point limits. The signal is also used in the calculation of circuit #3 subcooling.

Condenser pressure transducer circuit # 4 — The sensor is located on the discharge of compressor # 4 and is used to read saturated refrigerant pressure and temperature. The transducer will unload the compressor should a rise in head pressure occur which is outside the MicroTech set point limits. The signal is also used in the calculation of circuit #4 subcooling.

Sensor locations

Figure 31. Sensor locations (ALS125A thru 204A)

S13 S02

S04 S15

S11

Out In

S00 S08

Table 56. Sensor location chart (ALS125A thru 280A)

S12 S03 S01

DESCRIPTION

Suction temp. circ. #2

Liquid line temp. circ. #1

Liquid line temp. circ. #2

Evap. pressure transducer circ. #3

Cond pressure tranducer circ. #3

Suction temp circ. #3

Liquid line temp. circ. #3

Discharge temp. circ. #1

Discharge temp. circ. #2

Discharge temp. circ. #3

S14

S09

Figure 32. Sensor locations (ALS205A thru 280A)

S00

Out

S19

S22 S16

Compr. #3

S17

S08

In

S18 S13 S02 S04 S21 S15

Compr. #2

(Rep. only)

Inside control box on power

& control panels

S10

S11

S23

One sensor

S09

S12 S03

Compr. #1

S01 S20 S14

Table 57. Sensor location chart (ALS205A thru 280A)

SENSOR

NUMBER

S09

S10

S11

S12

S13

S14

S15

S16

S00

S01

S02

S03

S04

S06

S07

S08

S17

S18

S19

S20

S21

S22

S23

DESCRIPTION

Evap leaving water temp

Low pressure transducer circ. #1

Low pressure transducer circ. #2

High pressure transducer circ. #1

High pressure transducer circ. #2

Evap water temp reset (field supplied)

Demand limit (field supplied)

Evap entering water temp

Outside air temp

Percent circuit amps circ. #1

Percent circuit amps circ. #2

Suction temp circ. #1

Suction temp circ. #2

Liquid line temp circ. #1

Liquid line temp circ. #2

Low pressure transducer circ. #3

High pressure transducer circ. #3

Suction temp circ. #3

Liquid line temp circ. #3

Discharge temp circ. #1

Discharge temp circ. #2

Discharge temp circ. #3

Percent circuit amps circ. #3

IM 548 / Page 63

Page 64 / IM 548

Figure 33. Sensor locations (ALS300A thru 380A)

S14 S01

Compr. #1

S03 S12 S16 S17

Compr. #3

S09

S18 S19 S08

S11 S10

(Ref. only)

Inside control box on power

& control panels

S15

S04 S02 S13

Compr. #2 Compr. #4

S21 S20 S22 S23

Table 58. Sensor location chart (ALS300A thru 380A)

SENSOR

NUMBER

S09

S10

S11

S12

S13

S14

S15

S16

S00

S01

S02

S03

S04

S06

S07

S08

S17

S18

S19

S20

S21

S22

S23

DESCRIPTION

Evap leaving water temp

Low pressure transducer circ. #1

Low pressure transducer circ. #2

High pressure transducer circ. #1

High pressure transducer circ. #2

Evap water temp reset (field supplied)

Demand limit (field supplied)

Evap entering water temp

Outside air temp

Percent circuit amps circ. #1 & #3

Percent circuit amps circ. #2 & #4

Suction temp circ. #1

Suction temp circ. #2

Liquid line temp circ. #1

Liquid line temp circ. #2

Low pressure transducer circ. #3

High pressure transducer circ. #3

Suction temp circ. #3

Liquid line temp circ. #3

Low pressure transducer circ. #4

High pressure transducer circ. #4

Suction temp circ. #4

Liquid line temp circ. #4

S00

Outside air — This sensor is located on the back of the control box on compressor #1 side. It measures the outside air temperature, is used to determine if low ambient start logic is necessary and can be the reference for low ambient temperature lockout.

Suction temperature circuit #1 — The sensor is located in a well brazed to circuit #1 suction line. The purpose of the sensor is to measure refrigerant temperature to control and maintain proper superheat.

Suction temperature circuit #2 — The sensor is located in a well brazed to circuit #2 suction line. The purpose of the sensor is to measure refrigerant temperature to control and maintain proper superheat.

Suction temperature circuit #3 — The sensor is located in a well brazed to circuit #3 suction line. The purpose of the sensor is to measure refrigerant temperature to control and maintain proper superheat.

Suction temperature circuit #4 — The sensor is located in a well brazed to circuit #4 suction line. The purpose of the sensor is to measure refrigerant temperature to control and maintain proper superheat.

Liquid line temperature circuit #1 — The sensor is located in a well brazed to circuit #1 liquid line. It measures the refrigerant temperature and is used to calculate subcooling.

Liquid line temperature circuit #2 — The sensor is located in a well brazed to circuit #2 liquid line. It measures the refrigerant temperature and is used to calculate subcooling.

Liquid line temperature circuit #3 — The sensor is located in a well brazed to circuit #3 liquid line. It measures the refrigerant temperature and is used to calculate subcooling.

Liquid line temperature circuit #4 — The sensor is located in a well brazed to circuit #4 liquid line. It measures the refrigerant temperature and is used to calculate subcooling.

Demand limit — This requires a field connection of a 4-20 milliamp DC signal from a building automation system. It will determine the maximum number of cooling stages which may be energized.

Evaporator water temperature reset — This requires a 4-20 milliamp DC signal from a building automation system or temperature transmitter to reset the leaving chilled water set point.

Percent total unit amps — (optional) This is located in the power side of the control panel. An adjustable voltage resistor and a signal converter board sends a DC signal proportional to the total compressor motor current to the microprocessor.

Liquid presence sensor

Each compressor is equipped with a liquid sensor to assure that liquid flows to the compressor for cooling and sealing during operation. The sensor will shutdown the compressor in the event no liquid is sensed. At start-up the liquid sensor checks for excessive liquid in the compressor and will delay start until the compressor heater transfers the liquid out of the compressor and into the condenser. A liquid trip by the sensor will produce an alarm message on the MicroTech display.

High condenser pressure control

MicroTech is also supplied with high pressure transducers on each refrigerant circuit. Although the main purpose of the high pressure transducer is to maintain proper head pressure control, another purpose is to convey a signal to the MicroTech control to unload the compressor in the event of an excessive rise in discharge pressure to within 20 psi (138 kPa) below the condenser pressure control setpoint of 380 psig

(2620 kPa). The MicroTech control is set to not allow additional circuit loading approximately 30 psi

(207 kPa) below the high pressure switch trip setting. The high pressure alarm is in response to the signal sent by the pressure transducer. The high pressure transducer can be checked by elevating discharge pressure (see Mechanical High Pressure Safety Control) and observing the MicroTech display (or a

pressure gage), and unit operation as the pressures pass the rising high pressure values noted. After the test reset the High Condenser Pressure alarm set point to 380 psig (2620 kPa).

Mechanical high pressure safety control

The high pressure safety control is a single pole pressure activated switch that opens on a pressure rise.

When the switch opens, the control circuit is de-energized dropping power to the compressor and fan motor contactors. The switch is factory made to open at 400 psig (2760 kPa) (±10 psig) and reclose at 300 psig (2070 kPa). Although the high pressure switch will close again at 300 psig (2070 kPa), the control circuit will remain locked out and it must be reset through MicroTech.

The control is mounted on the compressor attached to a fitting ahead of the discharge shut off valve.

To check the control first manually load circuit #1 to 75% load. Adjust the High Condenser Pressure control to 415 psig (2862 kPa) through the “Alarm Spts” menu of the keypad. Remove wire 133 from terminal 20 of the MicroTech controller. This will disable all but one fan. Observe the cut out point of

IM 548 / Page 65

Page 66 / IM 548 the control through the MicroTech keypad display, or by means of a service gauge on the back seat port on the discharge service valve. Important: Closely monitor the High Pressure Control and stay within

reach of the emergency stop switch. Do not let the pressure exceed 420 psig (2900 kPa) during the

test. If the condenser pressure reaches 420 psig (2900 kPa) open the emergency stop switch. The

MicroTech keypad display may read slightly lower than a service gauge. Upon completion of the test

reset the High Pressure Control back to 380 psig (2620 kPa).

To check the control on circuit #2 repeat the same procedure after removing wire 233 from terminal

30.

Compressor motor protection

The compressors are supplied with two types of motor protection. Solid state electronic overloads mounted in the control box sense motor current within 2% of accuracy of the operating amps. The must trip amps are equal to 140% of unit nameplate compressor RLA. The must hold amps are equal to 125% of unit nameplate RLA. A trip of these overloads can result from the unit operating outside of normal conditions. Repeat overload trips under normal operation may indicate wiring or compressor motor problems. The overloads are manual reset and must be reset at the overload as well as through

MicroTech.

The compressors also have a solid state guardister circuit which provides motor over temperature protection. The guardister circuit has automatic reset but must also be reset through MicroTech.

FanTrol head pressure control

FanTrol is a method of head pressure control which automatically cycles the condenser fans in response to condenser pressure. This maintains head pressure and allows the unit to run at all ambient air temperatures.

All ALS units have independent circuits with the fans being controlled independently by the condensing pressure of each circuit. If one circuit is off all fans on that circuit will also be off. The use of multiple fans enables the unit to have excellent head pressure control at low outside ambients by cycling to maintain the compressor discharge pressure within the desired operating band.

At outdoor ambient temperatures above approximately 65°F (18.3°C) all of the fans for a circuit will be operating to achieve the most efficient unit operation. At any compressor load condition of 50% or above the unit has the highest overall efficiency with all fans operating. When the compressor unloads below 50% the last fan stage is cut off because the fan energy saved is more than the compressor power increase at this light loading. Below approximately 65°F (18.3°C) outdoor temperature the fans are cycled off as needed on each refrigerant circuit by the MicroTech control to maintain the compressor discharge pressure in the optimum range for best unit operation and highest overall efficiency.

Fans are controlled by MicroTech in response to the system discharge pressure. The use of MicroTech to stage on the fans as needed allows more precise control and prevents undesirable cycling of fans.

One fan always operates with the compressor and other fans are activated one at a time as needed. The control uses 6 stages of fan control, with 4 outputs to activate up to 6 additional fans per circuit.

MicroTech logic sequences fan contactors to stage one fan at a time. On units with 6 or 7 fans per circuit a single fan is cut off when 2 fans are started to achieve adding one operating fan. See Tables 59,

60 and 61.

Table 59. Fan staging and number of fans operating

ALS125A THRU ALS140A (FANS PER CKT=5)

MicroTech fan stage

Fan output relay on

0

—

1

1

2 3 4

1,2 1,2,3 1,2,3,4

Total fans operating 1 2 3 4 5

ALS155A THRU ALS170A (FANS PER CKT=6)

MicroTech fan stage

Fan output relay on

Total fans operating

0

—

1

1

1

2

2 3 4 5

1,2 1,2,3 1,2,4 1,2,3,4

3 4 5

ALS175A THRU 204A (FANS PER CKT=7)

6

MicroTech fan stage

Fan output relay on

Total fans operating

0

—

1

1

1

2

2

1,2

3

3

1,3

4

4

1,2,3

5

5

1,3,4 1,2,3,4

6

6

7

Notes:

On ALS155A thru 170A, two fans are controlled by fan output #4.

On ALS175A thru 204A, two fans each are contolled by fan outputs #3 and #4.

Table 60. Fan staging and number of fans operating

ALS205A THRU ALS220A CKTS 1 & 2 (FANS PER CKT=5)

MicroTech fan stage

Fan output relay on

0

—

1

1

2 3 4

1,2 1,2,3 1,2,3,4

Total fans operating 1 2 3 4 5

ALS205A THRU ALS220A CKT 3 (FANS PER CKT=6)

MicroTech fan stage

Fan output relay on

Total fans operating

0

—

1

1

1

2

2 3 4 5

1,2 1,2,3 1,2,4 1,2,3,4

3 4 5

ALS235A THRU 280A (FANS PER CKT=6)

6

MicroTech fan stage

Fan output relay on

Total fans operating

0

—

1

1

1

2

2

1,2

3

3

1,2,3

4

4

1,2,4 1,2,3,4

5

5

6

Note: On ALS205A thru-220A Ckt #3 only and ALS235A thru 280A two fans are controlled by fan

output #4.

Table 61. Fan staging and number of fans operating

ALS300A THRU ALS340A (FANS PER CKT=5)

MicroTech fan stage

Fan output relay on

0

—

1

1

2 3 4

1,2 1,2,3 1,2,3,4

Total fans operating 1 2 3 4 5

ALS360A THRU ALS380A (FANS PER CKT=6)

MicroTech fan stage

Fan output relay on

Total fans operating

0

—

1

1

1

2

2 3 4 5

1,2 1,2,3 1,2,4 1,2,3,4

3 4 5 6

Note: Each output relay controls one fan except output relay #4 which controls two fans.

Several factors are evaluated by the MicroTech controller to determine the number of fans to be operated.

These include:

1. What is the compressor loading as percent of full load?

2. What is the minimum lift pressure required at this load? (The lift pressure equals the discharge pressure

minus the suction pressure.)

3. A control pressure band is added to the minimum lift pressure to prevent fan cycling.

4. A target discharge pressure is determined by adding the minimum lift pressure to the suction pressure.

At any operating condition the MicroTech controller will determine the minimum lift pressure and a target discharge pressure, and will add or remove operating fans in sequence until the discharge pressure reaches the target value or falls within the control band of pressure set just above the target pressure value.

Each fan added has a decreasing percentage effect so the control pressure band is smaller when more fans are on and largest with only 1 or 2 fans on.

Unit operation, with FanTrol, is satisfactory down to outdoor temperatures of 30°F (–1.1°C). Below this temperature the SpeedTrol option is required to regulate the speed of the first fan on the system to adequately control the discharge pressure. With the SpeedTrol option unit operation down to 0°F (–

17.8°C) outdoor temperature is permitted assuming that no greater than a 5 mph wind is present. If

SpeedTrol is used in conjunction with wind baffles and hail guards, unit will operate down to -10°F (-

23°C).

For windy locations operating below 30°F (–1.1°C) outdoor air temperature, wind gusts must be prevented from blowing into the unit coils by either locating the unit in a protected area, by the addition of field supplied wind barriers, mounting the optional wind baffles on the unit or any combination of the above.

IM 548 / Page 67

Page 68 / IM 548

FanTrol operation example:

Unit operating at 100% load on both circuits

Suction Pressure = 65 psig (448 kPa)

Minimum lift pressure at 100% load = 120 psig (828 kPa)

Minimum discharge pressure =

65 + 120 psig = 185 psig (1276 kPa)

Discharge pressure control band = 35 psig (241 kPa)

Maximum discharge pressure =

185 + 35 = 220 psig (1517 kPa)

If the discharge pressure is between the minimum of 185 psig (1276 kPa) and maximum of 220 psig

(1517 kPa) the fan stages in operation are correct and if the pressure falls outside this range the MicroTech controller will stage fans on or off to bring it within range.

SpeedTrol and FanTrol will provide reasonable operating refrigerant discharge pressures at the ambient temperatures listed for them provided the coil is not affected by the existence of wind. Wind baffles must be utilized for low ambient operation below 30°F if the unit is subjected to winds greater than 5 mph.

Low ambient start

Low ambient start is incorporated into the MicroTech logic. The MicroTech will measure the difference between freezestat and evaporator pressure and determine the length of time the compressor will be allowed to run (to build up evaporator pressure) before taking the compressor off line. The danger of allowing the compressor to run for to long before building up evaporator pressure is that the evaporator could freeze. The low ambient timer is determined by the pressure difference between freezestat and evaporator pressure as shown in table . If the low ambient timer is greater than the maximum time allowed the MicroTech will shut off the compressor and display an alarm.

Table 62. Pressure difference vs. time to alarm

PRESSURE DIFFERENCE BETWEEN

FREEZESTAT AND EVAPORATOR

12 psig (84 kPa)

8 psig (56 kPa)

4 psig (28 kPa)

0 psig (0 kPa)

TIME

(SECONDS)

180

240

300

360

Phase/voltage monitor

The phase/voltage monitor is a device which provides protection against three-phase electrical motor loss due to power failure conditions, phase loss, and phase reversal. Whenever any of these conditions occur, a contact opens to the MicroTech controller (PVR Input) which then de-energizes all inputs.

When proper power is restored, contacts close and MicroTech enables compressors for operation.

When three-phase power has been applied, the output relay should close and the “run light” should come on. If the output relay does not close, perform the following tests.

1. Check the voltages between L1-L2, L1-L3 and L2-L3. These voltages should be approximately equal and within +10% of the rated three-phase line-to-line voltage.

2. If these voltages are extremely low or widely unbalanced check the power system to determine the cause of the problem.

3. If the voltages are good, using a phase tester, verify that phases are in A,B,C sequence for L1, L2 and

L3. Correct rotation is required for compressor operation. If required to do so by phase sequence, turn off the power and interchange any two of the supply power leads at the disconnect.

This may be necessary as the phase/voltage monitor is sensitive to phase reversal. Turn on the power.

The output relay should now close after the appropriate delay.

Compressor short cycling protection

MicroTech contains logic to prevent rapid compressor starting. Excessive compressor starts can be hard on starting components and create excessive motor winding temperatures. The anti-cycle timers are set for a 5 minute stop-to-start and a 15 minute start-to-start. Both are adjustable through MicroTech and can be manually overridden by the service technician.

Optional Controls

SpeedTrol head pressure control (optional)

The SpeedTrol system of head pressure control operates in conjunction with MicroTech’s standard head pressure control by modulating the motor speed on fans 11, 21 and 41 in response to condensing temperature. By reducing the speed of the last fan as the condensing pressure falls, the unit can operate at lower ambient temperatures. Start-up in low ambient is improved because the SpeedTrol fans 11, 21 and 41 do not start until the condenser pressure builds up.

The SpeedTrol fan motor is a single phase, 208-230/460 volt, thermally protected motor specially designed for variable speed application. The solid-state speed controls SC11, SC21 and SC41 are accessible through the panel directly above the control box. Units with 575 volt power have a transformer mounted inside the condenser fan compartment to step the voltage down to 230 volts for the

SpeedTrol motor.

The SpeedTrol control starts to modulate the motor speed at less than 65°F and maintains a minimum condensing pressure of 170 to 180 psig (1172 to 1241 kPa) at full circuit load. For part load operation the condensing pressure is allowed to fall below this level.

Reduced inrush start (optional)

Reduced inrush start is available on all voltage units and consists of a 2 contactor arrangement with a solid state time delay wired in series with the second contactor that energizes the second winding of each compressor motor. Its purpose is to limit current inrush to the compressors upon start-up. As each compressor starts, the power to the coil of the second contactor is delayed for 1 second. With the first compressor contactor energized the windings are connected in series to draw reduced amperage.

With the second contactor energized the windings are connected in parallel.

Control checkout is best accomplished by observation as each contactor is pulled in to see that the 1 second delay occurs before the second contactor pulls in.

Hot gas bypass (optional)

Hot gas bypass is a system for maintaining evaporator pressure at or above a minimum value that allows continous operation of the chiller at light load conditions. The purpose of doing this is to keep the velocity of the refrigerant as it passes through the evaporator high enough for proper oil return to the compressor when cooling load conditions are light.

The system consists of a pressure regulating valve with an integral solenoid as shown below. The solenoid valve is factory wired to open whenever the unit thermostat calls for the first stage of cooling.

The pressure regulating valve is factory set to begin opening at 58 psig (400 kPa). For low temperature operation the valve must be reset. This setting can be changed with an adjustment nut. To raise the pressure setting, turn the adjustment screw clockwise. To lower the setting, turn the screw counterclockwise. Do not force the adjustment beyond the range it is designed for, as this will damage the adjustment assembly.

With the unit operating at 50% or lower circuit load the regulating valve opening can be determined.

The regulating valve opening point can be determined by slowly reducing the system load or throttling the ball valve on the liquid line at the entrance to the evaporator. Observe the suction pressure with refrigerant gauges when the hot gas bypass valve cuts in. A slower but alternate method would be to lower the outlet water temperature to a value where the hot gas bypass valve starts to open. When the bypass valve starts to open, the refrigerant line on the evaporator side of the valve will begin to feel warm to the touch.

IM 548 / Page 69

Page 70 / IM 548

Figure 34. Hot gas bypass piping diagram

4.62 max.

3.17

1.75 for coil removal

5.88

1

⁄

4

" SAE external equalizer fitting

1

⁄

2

" conduit knockout

1.03

TYP.

2.33

.88

11.00 (1 1 ⁄

8

ODF)

11.06 (1

3

⁄

8

ODF)

Wind baffles and hail guards (optional)

Wind baffles can be supplied as a field installed option to reduce the negative effects on head pressure from wind blowing over the vertical condenser coils. Wind baffles will permit stable operation at reduced ambient temperatures and should be considered on all low ambient jobs or anytime that wind may be a factor.

Figure 35. Wind baffle and coil guard panel location (ALS125A thru 204A)

5

4 3 8

11 3 4 5

ALS175-195A

ALS125-170A

7 9

1 3

7 9

10 3

4 5

9 6

5 4 3 2

4

5

8

3

1

3

5 4 3 2

Table 63. Parts list (ALS125A thru 204A)

QUANTITIES FOR ONE SIDE OF UNIT

BALLOON

NUMBER PART DESCRIPTION

UNITS

125-170

UNITS

125-170

WITH

HAIL

GUARDS

UNIT

185

UNIT

185

WITH

HAIL

GUARDS

9

10

11

6

7

8

3

4

5

2

I

Channel / support

Panel /wind baffle

Screw / TTH 4-20 x H

Hex nut / 4-20

Lock washer /4"

Panel /end (L.H.)

Panel /end (R.H.)

Panel /hail Guard

Screw/TTH #10-24 x 2

Panel /wind baffle

Panel /hail guard

22

—

—

1

1

—

63

63

63

7

3

22

—

—

1

1

3

84

84

84

7

3

22

1

—

1

1

—

72

72

72

8

3

22

1

1

1

1

3

96

96

96

8

3

Installation sequence/instructions:

1. This assembly consists of channel supports, which are to be fastened to the coil frame with wind baffle panels, end panels and (optional) top hail guards secured to these supports. All hardware is supplied.

2. Prepare pilot holes for mounting channel supports to coil frame. In the frame at top and bottom of the condenser coil, find the pre-punched

1

⁄

8

" dia. holes in patterns of (2) holes approx. 3" apart. Use these holes as a guide for drilling .221 dia. (#2 drill) holes into top and bottom coil frame for mounting supports for the wind baffles.

3. Starting at control box end install the supports ➀ using (4)

1

⁄

4

-20 self-threading screws ➂. Note:

These

1

⁄

4

" dia. screws are required for adequate strength.

4. If hail guards are required these should be installed next. Starting at control box end, install hail guard panels ➇ & 11 on top of supports ➀ using

1

⁄

4

-20 self threading screws ➂. Lock washers ➄ and hex nuts ➃. Each panel overlaps the adjacent one. ➄ & ➃ are required to prevent loosening.

5. Starting at control box end fasten wind baffle panels ➁ & ➉ on front of supports ➀ using

1

⁄

4

-20 self threading screws ➂. Lock washers ➄ and hex nuts ➃. ➄ & ➃ are required to prevent loosening.

6. To install end panels: a. In the frame at both ends of the condenser coil, there are (6) small hex head screws. Remove (3) of these screws, leaving the top, bottom and the third from the bottom. (There is a large hole in

the end panel flange to clear the third from bottom screw head.)

b. Put the end panel ➅ or ➆ in place and reinstall the (3) screws which were previously removed.

c. Use the holes at the top, bottom and front of end panel as a template and drill .166 dia. (#19

drill) holes into flange of support ➀. Install the #10-24 self threading screws ➈.

d. Repeat procedure at other end.

7. Repeat steps #1 thru #6 on other side of unit.

IM 548 / Page 71

Figure 36. Wind baffle and coil guard panel location (ALS205A thru 280A)

Page 72 / IM 548

9

10

11

7

8

5

6

3

4

1

2

Table 64. Parts list (ALS205A thru 280A)

QUANTITIES FOR ONE SIDE OF UNIT

BALLOON

NUMBER PART DESCRIPTION

Channel/support

Panel/wind baffle

Screw/TTH

1

⁄

4

-20 x

3

⁄

4

Hex nut/

1

⁄

4

-20

Lock washer

1

⁄

4

"

Panel/end (L.H.)

Panel/end (R.H.)

Panel/hail Guard

Screw/TTH #10-24 x

1

⁄

2

Panel/wind baffle

Panel/hail guard

UNITS

205-280

99

1

1

—

11

4

99

99

22

1

—

UNITS

205-280

WITH

HAIL

GUARDS

11

4

132

132

132

1

1

4

22

1

1

Table 65. Parts list (ALS300A thru 340A)

BALLOON

NUMBER PART DESCRIPTION

QUANTITIES FOR ONE SIDE OF UNIT

UNITS

300-340

UNITS

300-340

WITH

HAIL

GUARDS

9

10

11

7

8

5

6

3

4

1

2

Channel/support

Panel/wind baffle

Screw/TTH 1 ⁄

4

-20 x 3 ⁄

4

Hex nut/ 1 ⁄

4

-20

Lock washer 1 ⁄

4

"

Panel/end (L.H.)

Panel/end (R.H.)

Panel/hail guard

Screw/TTH #10-24 x 1 ⁄

2

Panel/wind baffle

Panel/hail guard

12

4

108

108

108

2

2

—

44

2

—

12

4

144

144

144

2

2

4

44

2

2

Figure 37. Wind baffle and coil guard panel location (ALS300A thru 340A)

Installation sequence/instructions:

1. This assembly consists of channel supports, which are to be fastened to the coil frame with wind baffle panels, end panels and (optional) top hail guards secured to these supports. All hardware is supplied.

2. Prepare pilot holes for mounting channel supports to coil frame. In the frame at top and bottom of the condenser coil, find the pre-punched 1 ⁄

8

" dia. holes in patterns of (2) holes approx. 3" apart. Use these holes as a guide for drilling .221 dia. (#2 drill) holes into top and bottom coil frame for mounting supports for the wind baffles.

3. Starting at control box end install the supports ➀ using (4) 1 ⁄

4

-20 self-threading screws ➂. Note:

These 1 ⁄

4

" dia. screws are required for adequate strength.

4. If hail guards are required these should be installed next. Starting at control box end, install hail guard panels ➇ & 11 on top of supports ➀ using 1 ⁄

4

-20 self threading screws ➂. Lock washers ➄ and hex nuts ➃. Each panel overlaps the adjacent one. ➄ & ➃ are required to prevent loosening.

5. Starting at control box end fasten wind baffle panels ➁ & ➉ on front of supports ➀ using 1 ⁄

4

-20 self threading screws ➂. Lock washers ➄ and hex nuts ➃. ➄ & ➃ are required to prevent loosening.

6. To install end panels: a. In the frame at both ends of the condenser coil, there are (6) small hex head screws. Remove (3) of these screws, leaving the top, bottom and the third from the bottom. (There is a large hole in

the end panel flange to clear the third from bottom screw head.)

b. Put the end panel ➅ or ➆ in place and reinstall the (3) screws which were previously removed.

c. Use the holes at the top, bottom and front of end panel as a template and drill .166 dia. (#19

drill) holes into flange of support ➀. Install the #10-24 self threading screws ➈.

d. Repeat procedure at other end.

7. Repeat steps #1 thru #6 on other side of unit.

IM 548 / Page 73

Page 74 / IM 548

Table 66. Parts list (ALS360A thru 380A)

BALLOON

NUMBER PART DESCRIPTION

QUANTITIES FOR ONE SIDE OF UNIT

UNITS

360-380

UNITS

360-380

WITH

HAIL

GUARDS

7

8

5

6

9

3

4

1

2

Channel/support

Panel/wind baffle

Screw/TTH

1

⁄

4

-20 x

3

⁄

4

Hex nut/

1

⁄

4

-20

Lock washer 1 ⁄

4

"

Panel/end (L.H.)

Panel/end (R.H.)

Panel/hail guard

Screw/TTH #10-24 x

1

⁄

2

Installation sequence/instructions:

14

6

126

126

126

2

2

—

44

14

6

168

168

168

2

2

6

44

1. This assembly consists of channel supports, which are to be fastened to the coil frame with wind baffle panels, end panels and (optional) top hail guards secured to these supports. All hardware is supplied.

2. Prepare pilot holes for mounting channel supports to coil frame. In the frame at top and bottom of the condenser coil, find the pre-punched

1

⁄

8

" dia. holes in patterns of (2) holes approx. 3" apart. Use these holes as a guide for drilling .221 dia. (#2 drill) holes into top and bottom coil frame for mounting supports for the wind baffles.

3. Starting at control box end install the supports ➀ using (4)

1

⁄

4

-20 self-threading screws ➂. Note:

These

1

⁄

4

" dia. screws are required for adequate strength.

4. If hail guards are required these should be installed next. Starting at control box end, install hail guard panels ➇ on top of supports ➀ using

1

⁄

4

-20 self threading screws ➂. Lock washers ƒ and hex nuts ➃. Each panel overlaps the adjacent one. ➄ & ➃ are required to prevent loosening.

5. Starting at control box end fasten wind baffle panels ➁ on front of supports ➀ using

1

⁄

4

-20 self threading screws ➂. Lock washers ➄ and hex nuts ➃. ➄ & ➃ are required to prevent loosening.

6. To install end panels: a. In the frame at both ends of the condenser coil, there are (6) small hex head screws. Remove (3) of these screws, leaving the top, bottom and the third from the bottom. (There is a large hole in

the end panel flange to clear the third from bottom screw head.)

b. Put the end panel ➅ or ➆ in place and reinstall the (3) screws which were previously removed.

c. Use the holes at the top, bottom and front of end panel as a template and drill .166 dia. (#19

drill) holes into flange of support ➀. Install the #10-24 self threading screws ➈.

d. Repeat procedure at other end.

7. Repeat steps #1 thru #6 on other side of unit.

Figure 38. Wind baffle and coil guard panel location (ALS360A thru 380A)

IM 548 / Page 75

ALS controls, settings and functions

Table 67.

DESCRIPTION

Compressor Heaters

Compressor

Solenoid – Top

Compressor

Solenoid – Bottom

Compressor

Solenoid – Bottom

Evaporator Heater

Electronic Expansion

Valve Board

Electronic Expansion

Valve

Gardister Relay

Liquid Presence Sensor

Mechanical High

High Pressure Switch

MicroTech Unit

Controller

Motor Protector Relay

Overloads (Compressor)

Phase Voltage Monitor

FUNCTION

To provide heat to drive off liquid refrigerant

when compressor is off.

In circuit 1, 2 and 3 energizes to load 50% of compressor capacity.

In circuit 1, 2 and 3 energizes to unload 25% of compressor capacity.

In circuit 1, 2 and 3 energizes to load 25% of compressor capacity.

Coiled around the evaporator to prevent freezing the water inside.

To provide power and step control to the

EXV stepper motors commanded by the MCB250.

To provide efficient unit refrigerant flow and

control superheat.

To provide motor temperature protection at about

220°F (104°C).

To protect compressor from starting with liquid or running without liquid.

For UL, ETL, etc... safety code to prevent high pressure above the relief valve.

To control unit and all safeties. Refer to IM 549.

To provide voltage isolation to the input board (ADI).

To protect the compressor motor from over heating due to high amps.

To prevent reverse rotation of the motor and protect it from under/over voltage.

SYMBOL

HTR1,2,3

CS11,21,

31

CS12,22,

32

CS13,23,

33

HTR5

EXV (Bd)

EXV

GD1,2,3

LPS1,2,3

MHPR1,

2,3

SETTING

On, when compressor is off.

N/A

N/A

N/A

38°F (3.3°C)

N/A

In Controller Code

None,

Inherent in design

Factory set.

Not adjustable

400 psig (2760kPa)

MCB250 Refer to IM 549

MPR1,2,3 N/A

OL1-6

Defined by application

PVM1,2,3 N/A

RESET

N/A

N/A

N/A

N/A

N/A

N/A

N/A

Auto

Auto

Auto

Refer to IM 549

Auto

Control Box

Control Box

Manual Control Box

Auto

LOCATION

On the Compressor

On the Compressor

On the Compressor

On the Compressor

On the Cooler

Control Box

On the Compressor main liquid line

Control Box

On the Compressor

Control Box

Control box

Reduced Inrush

Time Delay

To provide 1 sec delay for reduced inrush.

TD5,6,7 N/A N/A Control Box

Signal Converter

Solenoid Valve

Hot Gas Bypass

Solenoid Valve

Liquid Line

Solenoid Valve

Liquid Injection

SpeedTrol Head

Pressure Control

To convert AC current signal volts to DC volts

To allow the unit to run with very low load.

To provide a positive shut off of liquid refrigerant when power is lost.

To only allow liquid injection when the compressor is running.

SIG.Con

V (SC)

SV5,6,9

SV1,2,7

SV3,4,8

Set 4Vdc for full load amps

0-75 psig

(0-517 kPa)

N/A

N/A

N/A

N/A

N/A

N/A

Control Box

Discharge Line

Liquid Line

On Compressor

Liquid Injection

To provide more uniform head pressure control.

SC11,21,

31

N/A N/A Above Control Box

Surge Capacitor

To protect from high voltage spikes and surges.

C1,2,3 N/A N/A

Control Box

Power Side

Notes: Symbol column shows applicable components for four-compressor units. For two- and three-compressor units, not all

components are applicable.

Page 76 / IM 548

ALS troubleshooting chart

Table 68.

PROBLEM

Compressor will not run.

Compressor Noisy or Vibrating

Compressor Overload

Relay Tripped or

Circuit Breaker Trip or Fuses Blown

Compressor Will

Not Load or Unload

Compressor Liquid

Injection

Protection Trip

High Discharge

Pressure

Low Discharge

Pressure

Low Suction

Pressure

High Suction

Pressure

POSSIBLE CAUSES

1. Main power switch open.

2. Unit S1 system switch open.

3. Circuit switch PS1,PS2,PS3 in pumpdown position.

4. Evap flow switch not closed.

5. Circuit breakers open.

6. Fuse blown or circuit breakers tripped.

7. Unit phase voltage monitor not satisfied.

8. Compressor overload tripped.

9. Defective compressor contactor or contactor coil.

10. System shut down by safety devices.

11. No cooling required.

12. Motor electrical trouble.

13. Loose wiring.

1. Compr. internal problem.

2. Liquid injection not adequate.

1. Low voltage during high load condition.

2. Loose power wiring.

3. Power line fault causing unbalanced voltage.

4. Defective or grounded wiring in the motor.

5. High discharge pressure.

1. Defective capacity control solenoids.

2. Unloader mechanism defective.

1. Liquid injection solenoid did not open at start.

2. Inadequate liquid to liquid injection at start due to a clogged filter drier or low charge.

3. Inadequate liquid to liquid injection during run.

1. Discharge shutoff valve partially closed.

2. Noncondensables in the system.

3. Fans not running.

4. Fan control out of adjustment.

5. System overcharged with refrigerant.

6. Dirty condenser coil.

7. Air recirculation from outlet into unit coils.

8. Air restriction into unit.

1. Wind effect at low ambients.

2. Condenser fan control not correct.

3. Low suction pressure.

4. Compressor operating unloaded.

1. Inadequate refrigerant charge quantity.

2. Inadequate liquid to liquid injection at start.

2. Clogged liquid line filter-drier.

3. Expansion valve malfunctioning.

4. Insufficient water flow to evaporator.

5. Water temperature leaving evaporator is too low.

6. Evaporator tubes fouled.

7. Evaporator head ring gasket slippage.

1. Excessive load – high water temperature.

2. Compressor unloaders not loading compressor.

3. Superheat is too low.

POSSIBLE CORRECTIVE STEPS

1. Close switch.

2. Check unit status on MicroTech display. Close switch.

3. Check circuit status on MicroTech display. Close switch.

4. Check unit status on MicroTech display. Close switch.

5. Close circuit breakers.

6. Check electrical circuits and motor windings for shorts or grounds.

Investigate for possible overloading.

Check for loose or corroded connections.

Reset breakers or replace fuses after fault is corrected.

7. Check unit power wiring to unit for correct phasing. Check voltage.

8. Overloads are manual reset. Reset overload at button on overload.

Clear alarm on MicroTech.

9. Check wiring. Repair or replace contactor.

10. Determine type and cause of shutdown and correct problem before attempting to restart.

11. Check control settings. Wait until unit calls for cooling.

12. See 6, 7, 8 above.

13. Check circuits for voltage at required points.

Tighten all power wiring terminals.

1. Contact McQuayService.

2. Check to assure liquid line sightglass is full during steady operation.

1. Check supply voltage for excessive voltage drop.

2. Check and tighten all connections.

3. Check supply voltage.

4. Check motor and Replace if defective.

5. See Corrective steps for high discharge pressure.

1. Check solenoids for proper operation. See capacity control section.

2. Replace.

1. Check and replace liquid injection solenoid.

2. Check liquid injection line sight glass.

If flashing check filter drier and unit charge.

3. Check liquid injection line sightglass.

If flashing check filter-drier and unit charge.

Discharge pressure too low. Protect condenser coil from wind.

1. Open shutoff valve.

2. Purge the noncondensables from the condenser coil after shutdown.

3. Check fan fuses and electrical circuits.

4. Check that unit setup in MicroTech matches the unit model number.

Check MicroTech condenser pressure sensor for proper operation.

5. Check for excessive subcooling above 30°F (–1.1°C).

Remove the excess charge.

6. Clean the condenser coil.

7. Remove the cause of recirculation.

8. Remove obstructions near unit.

1. Protect unit against excessive wind into vertical coils.

2. Check that unit setup in MicroTech matches the unit model number.

Check SpeedTrol fan on units with SpeedTrol option.

3. See Corrective Steps for low suction pressure.

4. See Corrective Steps for failure to load.

1. Check liquid line sightglass. Check unit for leaks.

Repair and recharge to clear sightglass.

2. Check pressure drop across filter-drier. Replace cores.

3. Check expansion valve superheat and valve opening position.

Replace valve only if certain valve is not working.

4. Check water pressure drop across the evaporator and Adjust gpm.

5. Adjust water temperature to higher value.

6. Inspect by removing water piping. Clean chemically.

7. Low suction pressure and low superheat both present may indicate an internal problem. Consult factory.

1. Reduce load or add additional equipment.

2. See Corrective Steps below for failure of compressor to load.

3. Check superheat on MicroTech display.

Check suction line sensor installation and sensor.

IM 548 / Page 77

Periodic Maintenance Log

Date of inspection:

Facility/job name:

Unit Model number:

Unit serial number:

Software identification:

Operating hours: (Menu #10)

Number of starts: (Menu #11)

Follow up service required:

Upper part of report completed:

Compressor #1

Compressor #1

Yes

M

No

M

Address:

City/State:

Physical location of unit:

Service technical (name):

Compressor #2

Compressor #2

Yes

General Actions To Be Taken:

M

No

M

Fill in above

Compressor #3

Compressor #3

Compressor #4

Compressor #4

Compressor operation:

1. Mechanical operation acceptable (noise, vibration, etc.)?

2. Look at cycling and cooling, is unit controlling at set points?

3. No refrigerant leaks (full liquid sightglass)?

4. Liquid line moisture indicator shows dry system?

5. Proper condensing fan operation?

6. Condenser coil clean?

7. No corrosion or paint problems?

Compressor electrical operation:

8. Satisfactory electrical operation?

9. MicroTech hardware operation satisfactory?

10. MicroTech software operation satisfactory?

Yes

M

M

M

M

M

M

M

No Explain all “No” checks

M

M

M

M

M

M

M

M

M

M

M

M

M

Data From MicroTech:

11. Unit status ______________ %

12. Circuit Status 1 _____ % Capacity

13. Water temperature - Evaporator:

14. No. of fan states active:

15. Evaporator pressure:

16. Condenser pressure:

17. EXV position – Steps open or percent open:

18. Superheat:

Circuit Status 2 _____ % Capacity Circuit Status 3 _____ % Capacity

Entering /Leaving ______________ / ______________

Circuit #1 Circuit #2

19. Subcooling:

20. Liquid line temperature:

21. Chiller % rated load amps – Unit:

22. Outside air temperature:

23. Leaving evaporator set point temperature:

24. Reset option programmed?

25. Is SpeedTrol included?

26. Current alarm: ___ ___ ___

27. Previous alarm – Show all:

Yes

M

No

M

Yes

M

No

M

Circuit #1

Ice storage unit?

SpeedTrol operation OK?

Alarm Type

Circuit #2

Date

Circuit #1

Circuit Status 4 _____ % Capacity

Circuit #3 Circuit #4

________________

________________

________________

________________

________________

________________

________________

________________

________________

________________

Yes

M

No

M

Yes

M

No

M

Circuit #3 Circuit #4

Alarm Type Date

Circuit #2

Circuit #3 Circuit #4

Data At Job Site:

28. Volts: L1 L2 L3

29. Amps:

30. Amps:

Comp #1

Comp #3

Ph 1

Ph 1

Ph 2

Ph 2

Ph 3

Ph 3

Comp#2

Comp#4

31. Vibration – Read every six months using IRD (or equal) unfiltered at flat on top of motor end:

Ph 1

Ph 1

Ph 2

Ph 2

Ph 3

Ph 3

In/Sec Comp #1

In/Sec Comp #2

In/Sec Comp #3

In/Sec Comp #4

Page 78 / IM 548

Limited Warranty

Chiller Products

Standard warranty

(United States and Canada)

McQuay International, hereinafter referred to as the “Company,” warrants that it will provide, at the

Company’s option, either free replacement parts or free repair of components in the event any product manufactured by the Company and used in the United States and Canada proves defective in material or workmanship within twelve (12) months from initial start-up or eighteen (18) months from the date shipped by the Company, whichever comes first.

In addition, labor to replace warranty parts during McQuay normal working hours is provided on products with rotary screw compressors, centrifugal compressors, and on absorption chillers.

Warranty labor is not provided for products with reciprocating compressors, on fluid coolers, on air cooled condensers, or on direct expansion coolers.

Factory start-up on absorption, centrifugal, and screw compressor products is mandatory and must be performed by McQuayService in the U.S. and by McQuayService or Authorized Service Agency in

Canada.

Exceptions

Warranty labor does not include diagnostic visits or inspections. All warranties apply only to the original owner. Replaced parts are warranted for the duration of the original warranty. Abuse, misuse, or alteration of the product in any manner voids the warranty. Accidental damage to the equipment is not warranted. All warranties are void if equipment start-up is not performed in accordance with this warranty statement.

Owner responsibility

For products started by other than McQuayService, the registration form accompanying the product must be completed and returned to the Company within ten (10) days of original equipment start-up.

If that is not done, the date of shipment shall be presumed to be the date of start-up and the warranty shall expire twelve (12) months from that date.

The owner is responsible for maintaining the equipment in accordance with the maintenance manual shipped with the unit. Failure to do so will void the warranty.

Assistance

To obtain assistance under this warranty, contact the selling agency. To obtain information regarding this warranty from the factory, contact McQuay International, P.O. Box 2510, Staunton, VA 24402-

2510; telephone 540-248-0711.

Sole remedy

This warranty constitutes the buyer’s sole remedy. It is given in lieu of all other warranties. There is no implied warranty of merchantability or fitness for a particular purpose. In no event and under no circumstance shall the Company be liable for incidental or consequential damages, whether the theory be breach of this or any other warranty, negligence or strict liability in tort.

No person (including any agent, salesman, dealer or distributor) has the authority to expand the

Company’s obligation beyond the terms of this express warranty, or to state that the performance of the product is other than that published by the Company.

Certain other extended warranties as described on the original purchase order may be in effect.

IM 548 / Page 79

®

13600 Industrial Park Boulevard, P.O. Box 1551, Minneapolis, MN 55440 USA (612) 553-5330

Printed on recycled paper containing at least 10% post-consumer recycled material.