McQuay AGZ 026BB Installation Manual

Installation and Maintenance Manual

Air-Cooled Scroll Compressor Chiller

AGZ 026BS/BH through 130BS/BH, Packaged AGZ 026BB/BM through 130BB/BM, Remote Evaporator

60 Hertz, R-22, R-407c

IMM A GZ -7

Group: Chiller Part Number: 331374001 Effective: February 2005 Supercedes: IOMM A GZ -6

Table of Contents

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

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

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

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

Installation......................................... 4

Handling.......................................................4

Location........................................................5

Vibration Isolators......................................12

Ambient Air T emperature Limitations........15

Water Piping...............................................17

Flow Switch................................................19

Water Connections......................................20

System Water Volume Considerations........20

Variable Speed Pumping ............................20

Glycol Solutions.........................................20

Operating/Standby Limits...........................24

Evaporator Flow and Pressure Drop Water Flow

Limitations..................................................24

Wind Baffles and Hail Guards....................26

Optional Features............................28

Controls......................................................28

BAS Interface.............................................28

Remote Operator Interface Panel...............29

Physical Data ...................................31

Startup..............................................59

Pre Start-up................................................ 59

Start-Up ..................................................... 59

Shutdown................................................... 60

Water Piping Checkout.............................. 60

Refrigerant Piping Checkout...................... 60

Electrical Check Out.................................. 61

Component Operation.....................61

Hot Gas Bypass (Optional)........................ 61

VFD Low Ambient Control (Optional) ...... 62

Filter-Driers............................................... 62

System A djustment.................................... 62

Liquid Line Sight Glass............................. 62

Refrigerant Charging ................................. 62

Thermostatic Expansion Valve .................. 63

Crankcase Heaters ..................................... 63

Evaporator ................................................. 63

Phase Voltage Monitor (Optional)............. 63

Unit Maintenance.............................64

Preventive Maintenance Schedule............. 65

Service...............................................66

Liquid Line Solenoid Valve ....................... 66

Evaporator ................................................. 67

Refrigerant Charging ................................. 67

Electrical Data, Standard Ambient 36

Electrical Data High Ambient........46

Dimensional Data............................ 54

Warranty Statement ........................68

AGZ Troubleshooting Chart...........69

R-407C Units.................................... 57

Manufactured in an ISO Certified facilit

"McQuay" is a registered trademark of McQuay International

Illustrations and data cover McQuay International products at the time of publication and we reserve the right to

make changes in design and construction at anytime without notice.

2 AGZ 026B through 130B IMM AGZ-7

Introduction

General Description

McQuay Air-Cooled Global Water Chillers are complete, self-contained automatic refrigerating units. Every unit is completely assembled, factory wired, charged, and tested. Each unit consists of twin air-cooled condensers with integral subcooler sections, two tandem or triple scroll compressors, brazed-plate or replaceable tube, dual circuit shell-and-tube evaporator, and complete refrigerant piping. Liquid line components include manual liquid line shutoff valves, sight-glass/moisture indicators, solenoid valves, and thermal expansion valves. Other features include compressor crankcase heaters, an evaporator heater for chilled water freeze protection, limited pumpdown during “on” or “off” periods, automatic compressor lead-lag to alternate the compressor starting sequence, and sequenced starting of compressors.

The electrical control center includes all equipment protection and operating controls necessary for dependable automatic operation. Condenser fan motors are protected in all three phases and started by their own three-pole contactors.

Manuals

This manual covers the installation, maintenance and service for dual circuit, AGZ, scroll compressor chillers. Operating information is contained in the operating manual OM AGZ-1.

Inspection

Check all items carefully against the bill of lading. Inspect all units for damage upon arrival. Report shipping damage and file a claim with the carrier. Check the unit nameplate before unloading, making certain it agrees with the power supply available. McQuay is not responsible for physical damage after the unit leaves the factory.

Note: Unit shipping and operating weights are available in the Physical Data tables beginning on page 31.

Nomenclature

A G Z - XXX B S

Scroll Compressor

Air-Cooled

Global

Application S= Standard Ambient, Packaged M= Standard Ambient, Remote H= High Ambient, Packaged B= High Ambient, Remote

Design Vintage

IMM AGZ-7 AGZ 026B through 130B 3

Model Size (Nominal Tons)

Installation

Note: Installation is to be performed by qualified personnel who are familiar

with local codes and regulations.

WARNING

Sharp edges on unit and coil surfaces are a potential hazard to personal safety.

Avoid contact with them.

Handling

Be careful to avoid rough handling of the unit. Do not push or pull the unit from anything other than the base. Block the pushing vehicle away from the unit to prevent damage to the sheet metal cabinet and end frame (see Figure 1).

To lift the unit, 2 1/2" (64mm) diameter lifting tabs are provided on the base of the unit. Arrange spreader bars and cables to prevent damage to the condenser coils or cabinet (see Figure 2).

Figure 1, Suggested Pushing Arrangement

Blocking is required across full width

Figure 2, Suggested Lifting Arrangement

Number of fans may vary

from this diagram. The lifting

Spreader bars

required

(use caution)

method will remain the same.

All rigging locations must be used.

4 AGZ 026B through 130B IMM AGZ-7

Location

Unit Placement

Figure 3, Clearances

AGZ units are for outdoor applications and can be mounted either on a roof or at ground level. For roof mounted applications, install the unit on a steel channel or I-beam frame to support the unit above the roof. For ground level applications, install the unit on a

4 FT. (1220mm) CLEARANCE FOR

SERVICE ACCESS

substantial base that will not settle. A onepiece concrete slab with footings extended below the frost line is recommended. Be sure the foundation is level within 1/2" (13mm) over its length and width. The foundation must be strong enough to support the weights listed in the Physical Data Tables beginning on page 31.

Table 1, Recommended Minimum Clearances

Model Size

026B – 070B 075B – 130B

Coil Side “A”

ft (m)

4 (1.2) 8 (2.4) 6 (1.8) 4 (1.2) 4 (1.2) 6 (1.8) 12 (3.6) 8 (2.4) 4 (1.2) 4 (1.2)

“B”

ft (m)

“C”

ft (m)

End Opposite

Controls ft (m)

Clearances

Do not block the flow of air to and from the condenser coil. Restricting airflow or allowing air recirculation will result in a decrease in unit performance and efficiency because discharge pressures are increased. There must be no obstruction above the unit that would deflect discharge air downward where it could be recirculated back to the inlet of the condenser coil. The condenser fans are propeller type and will not operate with ductwork.

Install the unit with enough side clearance for air to enter the coil and for servicing. Provide service access to the evaporator, compressors, electrical control panel and piping components.

Do not allow debris to accumulate near the unit where it could be drawn into the condenser coil. Keep condenser coils and fan discharge free of snow or other obstructions to permit adequate airflow for proper operation.

AIR FLOW

The recommended minimum side clearance be tw een two units is dimension “B’ in table on this page.

AIR FLOW

The unit must not be installed in a pit or encl osure that is deeper or taller than the height of the unit unless extra space is provided. The minimum clearance on each side of the unit is dimension “C” in tabl e on this page.

SEE ATTACHED TABLE

DIMENSION “A”

SEE ATTACHED TABLE

DIMENSION “A”

Control Panel End

AIR

DISCHARGE

AIR FLOW

“B”

AIR

DISCHARGE

“C” “C”

ft. (m)

4 FT. (1220) CLEARANCE FOR

SERVICE ACCESS

AIR

DISCHARGE

IR FLOW

IMM AGZ-7 AGZ 026B through 130B 5

Restricted Air Flow General

The clearances required for design-life operation of AGZ air-cooled condensers are described in the previous section. Occasionally, these clearances cannot be maintained due to site restrictions such as units being too close together or a fence or wall restricting airflow, or both.

Fortunately, the McQuay AGZ chillers have several features that can mitigate the problems attributable to restricted airflow.

• The condenser section is shaped as shown Figure 4. This allows inlet air for these coils to come in from either side. A vertical coil and its adjacent angled coil are manifolded together to serve one refrigerant circuit.

• The MicroTech II™ control is proactive in response to “off-design conditions”. In the case of single or compounded influences restricting airflow to the unit, the microprocessor will act to keep the compressor(s) running (possibly at reduced capacity) rather than allowing a shut-off on high discharge pressure.

• The MicroTech II™ control can be programmed to sequence the compressors in the most advantageous way. For example, in the diagram shown below, it might be desirable to program circuit #1 to be the lag circuit (last circuit to reach full load) during periods of high ambient temperatures.

Figure 4, Coil and Fan Arrangement

Building

Circuit #1 Circuit #2

NOTE: Models AGZ 026 to 035 do not have an interior slanted coil.

The following sections discuss the most common situations of condenser air restriction and give capacity and power adjustment factors for each. Note that in unusually severe conditions, the MicroTech II™ controller would adjust the unit operation to remain online until a less severe condition is reached.

6 AGZ 026B through 130B IMM AGZ-7

Case 1, Building or Wall on One Side of One Unit

The existence of a screening wall or the wall of a building in close proximity to an air-cooled chiller is common in both rooftop and ground level applications. Hot air recirculation on the coils adjoining the wall will increase compressor discharge pressure, decreasing capacity and increasing power consumption. Only the compressor(s) connected to these coils will be affected. Circuits opposite the wall are unaffected.

When close to a wall, it is desirable to place chillers on the north or east side of them. It is also desirable to have prevailing winds blowing parallel to the unit’s long axis. The worst case is to have wind blowing hot discharge air into the wall.

Figure 5, Unit Adjacent to Wall

Figure 6, Adjustment Factors

3.0

2.0

1.0

075-130

4.5 ft.

(1.4m)

6 ft.

(1.8m)

8 ft.

(2.4m)

AGZ

026-070

3.5 ft.

(1.0m)

4 ft.

(1.2m)

6 ft.

(1.8m)

4.0

3.0

2.0

AGZ

6 ft.

8 ft.

AGZ

026-070

3.5 ft.

(1.0m)

4 ft.

(1.2m)

6 ft.

(1.8m)

075-130

4.5 ft.

(1.4m)

(1.8m)

(2.4m)

IMM AGZ-7 AGZ 026B through 130B 7

Case 2, Two Units Side By Side

Two or more units sited side by side are common. If spaced closer than 12 feet (3.7 meters) or 8 feet (2.5meters) depending on size, it is necessary to adjust the performance of each unit; circuits adjoining each other are affected. NOTE: This case applies only to two units side by side. See Case 3 for three or more parallel units. If one of the two units also has a wall adjoining it, see Case 1. Add the two adjustment factors together and apply to the unit located between the wall and the other unit.

Mounting units end to end will not necessitate adjusting performance. Depending on the actual arrangement, sufficient space must be left between the units for access to the control panel door opening and/or evaporator tube removal. See “Clearance” section of this guide for requirements for specific units.

Figure 7, Two Units Side by Side

Figure 8, Adjustment Factor

3.0

2.0

1.0

GZ 075-130

GZ 026-070

(2.7)

6.5

(2.0)

(3.0)

(2.1)

(3.3)

7.5

(2.2)

(3.6)

(2.4)

GZ 075-130

GZ 026-070

6.0

4.0

2.0

(2.7)

6.5

(2.0)

(3.0)

(2.1)

(3.3)

7.5

(2.2)

(3.6)

(2.4)

8 AGZ 026B through 130B IMM AGZ-7

Case 3, Three or More Units Side By Side

When three or more units are side by side, the outside chillers (1 and 3 in this case) are influenced by the middle unit only on their inside circuits. Their adjustment factors will be the same as Case 2. All inside units (only number 2 in this case) are influenced on both sides and must be adjusted by the factors shown below.

Figure 9, Three or More Units

GZ 075-130 GZ 026-070

Chiller 1 Chiller 2 Chiller 3

Figure 10, Adjustment Factor

4.0

3.0

2.0

1.0

(4.6)

(3.3)

(4.9)

(3.7)

(5.2)

(4.0)

(5.5)

(4.3)

GZ 075-130

GZ 026-070

8.0

6.0

4.0

2.0

(4.6)

(3.3)

(4.9)

(3.7)

(5.2)

(4.0)

(5.5)

(4.3)

IMM AGZ-7 AGZ 026B through 130B 9

Case 4, Open Screening Walls

Decorative screening walls are often used to help conceal a unit either on grade or on a rooftop. These walls should be designed such that the combination of their open area and distance from the unit do not require performance adjustment. It is assumed that the wall height is equal to or less than the unit height when mounted on its base support. This is usually satisfactory for concealment. If the wall height is greater than the unit height, see Case 5, Pit Installation.

The distance from the ends of the unit to the end walls should be sufficient for service, opening control panel doors, and pulling evaporator tubes, as applicable.

If each side wall is a different distance from the unit, the distances can be averaged providing either wall is not less than 8 feet (2.4 meters) from the unit. For example, do not average 4 feet and 20 feet to equal 12 feet.

Figure 11, Open Screening Walls

Figure 12, Wall Free Area vs Distance

AGZ

026-070

(1.2)

3.5

(1.0)

3.0

(0.9)

2.5

(0.7)

AGZ

075-130

(1.8)

(2.0)

(1.2)

(0.9)

01020304050

10 AGZ 026B through 130B IMM AGZ-7

Case 5, Pit/Solid Wall Installation

Pit installations can cause operating problems and great care should be exercised if they are to be used on an installation. Recirculation and restriction can both occur. A solid wall surrounding a unit is substantially the same as a pit and the data presented here should be used.

Steel grating is sometimes used to cover a pit to prevent accidental falls or trips into the pit. The grating material and installation design must be strong enough to prevent such accidents, yet provide abundant open area or serious recirculation problems will occur. Have any pit installation reviewed by McQuay application engineers prior to installation to make sure it has sufficient air-flow characteristics. The installation design engineer must approve the work to avoid the risk of accident.

Figure 13, Pit Installati on

Figure 14, Adjustment Factor

D=4

(1.4)

D=6

(1.8)

D=5 (2.0)

D=8 (2.4)

075-130

D=10

AGZ

026-070

AGZ

075-130

AGZ

(3.1)

AGZ

026-070

D=7 (2.1)

D=4 (1.4)

D=6 (1.8)

D=5 (2.0)

D=8 (2.4)

AGZ

075-130

D=10

(3.1)

AGZ

026-070

D=7 (2.1)

AGZ

026-070

AGZ

075-130

IMM AGZ-7 AGZ 026B through 130B 11

Sound Isolation

The low sound level of the AGZ chiller is suitable for most applications. When additional sound reduction is necessary, locate the unit away from sound sensitive areas. Avoid locations beneath windows or between structures where normal operating sounds may be objectionable. Reduce structurally transmitted sound by isolating water lines, electrical conduit and the unit itself. Use wall sleeves and rubber isolated piping hangers to reduce transmission of water or pump noise into occupied spaces. Use flexible electrical conduit to isolate sound transmission through electrical conduit. Spring isolators are effective in reducing the low amplitude sound generated by scroll compressors and for unit isolation in sound sensitive areas.

Vibration Isolators

Vibration isolators are recommended for all roof-mounted installations or wherever vibration transmission is a consideration. Table 2 lists isolator loads for all unit sizes.

Neoprene-in-Shear Dimensions

Color Code L W H B C D Gray 5.5 3.37 1.75 0.5 4.12 0.56 Black, Red 6.25 4.62 1.62 0.5 5.0 0.56

Spring Isolator Dimensions

Figure 15 shows isolator locations. See Dimensional Data starting on page 36 for detailed mounting hole locations.

Isolators are also recommended for slab installations, primarily to keep the unit base from resting its entire length directly on the slab.

Isolator Installation

The unit should be initially installed on shims or blocks at the listed free height. When all piping, wiring, flushing, charging, etc. is completed, adjust the springs upward to load them and to provide clearance to remove the shims or blocks.

Installation of spring isolators requires flexible piping connections and at least three feet of conduit flex tie-ins. Piping and conduit must be supported independently of the unit.

Figure 15, Isolator Locations

4 or 6 FAN UNIT 8 FAN UNIT

CONTROL

PANEL

12 AGZ 026B through 130B IMM AGZ-7

CONTROL

PANEL

Table 2, AGZ-BS/BH, Isolator Loads At Each Mounting Location (With Aluminum Fins)

Unit Size

026B 4 1281 580 941 426 1020 462 748 339 - - - - 3990 1807 72 32 030B 4 1297 588 952 431 1032 467 759 344 - - - - 4040 1830 72 32 035B 4 1283 581 942 427 1069 484 786 356 - - - - 4080 1848 72 32 040B 4 1360 616 940 426 1082 490 748 339 - - - - 4130 1871 72 32 045B 4 1377 624 952 431 1148 520 793 359 - - - - 4270 1934 72 32 050B 4 1384 627 1016 460 1153 522 847 384 - - - - 4400 1993 119 54 055B 4 1391 630 1085 492 1159 525 905 410 - - - - 4540 2057 119 54 060B 4 1410 639 1099 498 1175 532 916 415 - - - - 4600 2084 142 65 065B 4 1382 626 1214 550 1205 546 1059 480 - - - - 4860 2202 142 65 070B 4 1419 643 1246 564 1238 561 1087 492 - - - - 4990 2260 217 99 075B 6 1854 840 1411 639 1854 840 1411 639 - - - - 6530 2958 217 99 085B 6 1942 880 1479 670 1856 841 1413 640 - - - - 6690 3031 217 99 090B 6 1975 895 1450 657 1975 895 1450 657 - - - - 6850 3103 217 99 100B 8 1464 663 1341 607 1219 552 1400 634 1282 581 1164 527 7870 3565 289 131 110B 8 1513 685 1358 615 1204 545 1513 685 1358 615 1204 545 8150 3692 289 131 120B 8 1656 750 1486 673 1317 597 1582 717 1420 643 1259 570 8720 3950 289 131 130B 8 1714 776 1508 683 1303 590 1714 776 1508 683 1303 590 9050 4100 289 131

No.

Fans

1 2 3 4 5 6 Total Unit

lb kg lb kg lb kg lb kg lb kg lb kg lb kg lb. kg

NOTE (1): Additional weight for copper coils is per mounting location.

(1) Copper

Fin Add

Table 3, Isolator Kit Numbers

AGZ

Model

Spring Kit

Part No. R-I-S Kit Part No.

026, 030

035

330349603 330349603 330349605 330349606 330349607 330349609 330349612 330349613 330349614 330349702 330349703 330349704 330349704 330349705 330349706 330349707 330349708 330349709

040, 045

050

055 060 065, 070

075, 085

090

100 110 120,130

Table 4, Isolator Locations

AGZ-B, Chillers

Operating Weight. Neoprene-In-Shear Mountings Spring-Flex Mountings

Unit Size

026B 030B 035B 040B 045B 050B 055B 060B 065B 070B 075B 085B 090B 100B 110B 120B 130B

NOTES:

1. Neoprene-in-shear isolators: Gray=RP-3 Gray, Black=RP-4 Black, Red=RP-4 Red.

lbs kg 3990 1807 4040 1830 4080 1848 4130 1871 4270 1934 4400 1993 4540 2057 4600 2084 4860 2202 4990 2260 6530 2958 6690 3031 6850 3103 7870 3565 8150 3692 8720 3950 9050 4100

1 2 3 4 5 6 1 2 3 4 5 6

Black Gray Gray Gray - - Orange Purple Purple Red - Black Gray Gray Gray - - Orange Purple Purple Red - Black Gray Gray Gray - - Orange Purple Purple Red - Black Gray Black Gray - - Orange Purple Purple Red - Black Gray Black Gray - - Orange Purple Purple Red - Black Gray Black Gray - - Orange Purple Purple Red - Black Black Black Gray - - Orange Purple Purple Purple - Black Black Black Gray - - Orange Purple Orange Purple - Black Black Black Black - - Orange Orange Orange Purple - Black Black Black Black - - Orange Orange Orange Purple - -

Red Black Red Black - - Gray Orange Gray Orange - Red Black Red Black - - Gray Orange Gray Orange - Red Black Red Black - - Gray Orange Gray Orange - -

Black Black Black Black Black Black Orange Orange Orange Orange Orange Orange

Red Black Black Red Black Black Green Orange Orange Green Orange Orange Red Red Black Red Red Black Green Green Orange Green Green Orange Red Red Black Red Red Black Green Green Orange Green Green Orange

IMM AGZ-7 AGZ 026B through 130B 13

Table 5, AGZ BM/BB, Isolator Loads At Each Mounting Location (With

Aluminum Fins)

AGZ-

BM/BB

Model

AGZ 026

AGZ 030

AGZ 035

AGZ 040

AGZ 045

AGZ 050

AGZ 055

AGZ 060

AGZ 065

AGZ 070

NOTE (1): Additional weight for copper coils is per mounting location.

Shipping

lbs 3550 3600 1227 901 849 623 3600 72

kg 1608 1631 556 408 385 282 1631 32

lbs 3550 3600 1227 901 849 623 3600 72

kg 1608 1631 556 408 385 282 1631 32

lbs 3550 3600 1227 901 849 623 3600 72

kg 1608 1631 556 408 385 282 1631 32

lbs 3550 3610 1261 872 873 604 3610 72

kg 1608 1635 571 395 395 274 1635 32

lbs 3590 3650 1275 881 883 611 3650 72

kg 1626 1653 578 399 400 277 1653 32

lbs 3730 3800 1295 951 896 658 3800 119

kg 1690 1721 587 431 406 298 1721 54

lbs 3780 3850 1303 1016 860 671 3850 119

kg 1712 1744 590 460 390 304 1744 54

lbs 3820 4040 1367 1066 903 704 4040 142

kg 1730 1830 619 483 409 319 1830 65

lbs 3970 4070 1305 1146 862 757 4070 142

kg 1798 1844 591 519 390 343 1844 65

lbs 4080 4180 1278 1192 885 825 4180 217

kg 1848 1894 579 540 401 374 1894 99

Operating.

Loc. 1 Loc. 2 Loc. 3 Loc. 4 Total

(1) Add’l for

Copper Fins

Table 6, Isolator Loads At Each Mounting Location (With Aluminum Fins)

AGZ-

BM/BB

Model

AGZ 075

AGZ 085

AGZ 090

AGZ 100

AGZ 110

AGZ 120

AGZ 130

NOTE (1): Additional weight for copper coils is per mounting location.

Shipping

lbs 5510 5630 1649 1166 1649 1166 - - 5630 217

kg 2496 2550 747 528 747 528 - - 2550 99

lbs 5670 5790 1734 1227 1657 1172 - - 5790 217

kg 2569 2623 786 556 751 531 - - 2623 99

lbs 5830 5950 1770 1205 1770 1205 - - 5950 217

kg 2641 2695 802 546 802 546 - - 2695 99

lbs 6820 6970 1323 1188 1053 1265 1135 1006 6970 289

kg 3089 3157 599 538 477 573 514 456 3157 131

lbs 7080 7230 1396 1205 1014 1396 1205 1014 7230 289

kg 3207 3275 632 546 459 632 546 459 3275 131

lbs 7360 7480 1477 1275 1073 1411 1218 1026 7480 289

kg 3334 3388 669 578 486 639 552 465 3388 131

lbs 7640 7760 1555 1293 1032 1555 1293 1032 7760 289

kg 3461 3515 704 586 467 704 586 467 3515 131

Wt.

Operating

Wt.

Loc 1 Loc 2 Loc 3 Loc 4 Loc 5 Loc 6 TOTAL

(1) Add’l for

Copper Fins

Table 7, Isolator Kit Part Numbers

AGZ-BM Model 026 - 035 040 - 060 065 070 075 - 090 100, 110 120, 130

Spring Kit Part No.

R-I-S Kit Part No.

330349601 330349602 330349603 330349604 330349608 330349610 330349611 330349701 330349701 330349703 330349703 330349706 330349707 330349708

14 AGZ 026B through 130B IMM AGZ-7

Table 8,AGZ BM/BB, Isolator Locations

ACZ-BS, AGZ-BM Less Evaporator Units

AGZ-

BM/BB

Model

026 030 035 040 045 050 055 060 065 070 075 085 090 100 110 120 130

NOTE (1): Position #4 is a CP-1, single spring isolator for A CZ 030 to 065 and AGZ 026 to 060. All

Operating

Weight

lbs kg 1 2 3 4 5 6 1 2 3 4 (1) 5 6

3600 1631 Black Gray Gray Green - - Orange Purple Red Orange 3600 1631 Black Gray Gray Green - - Orange Purple Red Orange - 3600 1631 Black Gray Gray Green - - Orange Purple Red Orange - 3610 1635 Black Gray Gray Green - - Orange Purple Purple Orange - 3650 1653 Black Gray Gray Green - - Orange Purple Purple Orange - 3800 1721 Black Gray Gray Green - - Orange Purple Purple Orange - 3850 1744 Black Gray Gray Green - - Orange Purple Purple Orange - 4040 1830 Black Gray Gray Green - - Orange Purple Purple Orange - 4070 1844 Black Black Gray Gray - - Orange Purple Purple Red - 4180 1894 Black Black Gray Gray - - Orange Orange Purple Red - 5630 2550 Red Black Red Black - - Green Orange Green Orange - 5790 2623 Red Black Red Black - - Green Orange Green Orange - 5950 2695 Red Black Red Black - - Green Orange Green Orange - 6970 3157 Black Black Black Black Black Black Orange Orange Purple Orange Orange Purple 7230 3275 Black Black Black Black Black Black Orange Orange Purple Orange Orange Purple 7480 3388 Red Black Black Red Black Black Green Orange Purple Green Orange Purple 7760 3515 Red Black Black Red Black Black Green Orange Purple Green Orange Purple

others are CP-2, two

Neoprene-In-Shear Mountings Spring-Flex Mountings

spring.

Ambient Air Temperature Limitations

Standard/High A mbient Panels

Models AGZ-B (26 to 130 tons, two circuit) have electrical data and subsequent field wiring requirements that are tailored to individual applications.

There are many installations where the expected summer ambient air temperatures will be at 105°F (40.1°C) or less, resulting in smaller unit electrical requirements compared to operation at 106°F (41.1) and above. In these lower temperature cases, there can be considerable installation cost savings by using smaller and more appropriate electrical service.

Therefore, the AGZ electrical data is divided into two classifications based on the design ambient temperature where the unit will operate. Standard Ambient unit electrical data (BS and BM models) is for operation in ambient temperatures of 105°F (40.1°C) or less. Units with the High Ambient designation (BH and BB models) are for use above 105°F (40.1°C) to 125°F (51.7°C).

The AGZ-B units for high ambient operation require the addition of the High Ambient Control Panel Option, which includes the addition of a small fan with a filter in the air intake to cool the control panel, and a unit nameplate that lists the larger electrical requirements.

All units with the optional VFD low ambient fan control automatically include the High Ambient Control Panel Option. Operation of the VFD generates a quantity of panel heat best removed by use of a control panel fan.

IMM AGZ-7 AGZ 026B through 130B 15

Winter Operation Temperatures

0°F to 34°F 35°F and Above

Fan Control Optional VFD (1) Standard FanTrol (2) Design Ambient Air T emperature

Electrical Data (3)

≤105°F >106°F ≤105°F >106°F

Standard

Ambient

High

Ambient

Standard Ambient

High

Ambient

Panel Fan Required (4) Yes Yes No Yes Model Designator (5)

Packaged BS BH BS BH Remote Evaporator BM BB BM BB

NOTES

1. VF D is variable spe ed, fan control through the Micro Tech Ii controller.

2. FanTrol is fan cycling off discharge pressure.

3. Standard Ambient electrical data begins on page 36, High Ambient data begins on page 46.

4. The VFD option automatically includes the factory-installed panel fan and filter set

5. The designator is the last two characters in the model number, i.e. AGZ 100BS.

Panel Ratings

Voltage

208-230

240

380-460

575

Standard

Standard Options

Panel

Optional

VFD

High Short Circuit

Panel (kA)

High Interrupt Panel w/

Disconnect Swt. (kA)

35 5 120 120 35 5 100 100 35 5 65 65

5 5 25 25

Water Flow Limitations, Constant Flow

The evaporator flow rates and pressure drops shown on page 25 are for full load design purposes. The maximum flow rate and pressure drop are based on a 6-degree temperature drop. Avoid higher flow rates with resulting lower temperature drops to prevent potential control problems resulting from very small control bands and limited start up/shut off temperature changes.

The minimum flow and pressure drop is based on a full load evaporator temperature drop of 16-degrees.

Evaporator flow rates below the minimum values can result in laminar flow causing freeze-up problems, scaling and poor control. Flow rates above the maximum values will result in unacceptable pressure drops and can cause excessive erosion, potentially leading to failure.

Water Flow Limitations, Variable Flow

The full load, minimum flow limitation for constant flow is not to be confused with the part load minimum flow rate that must be maintained for chillers operating in primary variable flow pumping systems. As chiller capacity drops, the flow rate for this pumping system will reduce proportionally. See the following table for the part load minimum flow rates.

Other design practices for variable flow systems requiring a range of evaporator flow rates can be found below.

16 AGZ 026B through 130B IMM AGZ-7

These minimum flow rates assume that flow will be reduced proportionally to the cooling load.

Table 9, Minimum Part Load Flow Rates

AGZ Model 010 013 017 020 025 029 034 026 030 035 040 045

Minimum Part

Load Flow (GPM)

AGZ Model 050 055 060 065 070 075 085 090 100 110 120 130

Minimum Part

Load Flow (GPM)

10 13 15 20 22 27 33 26 29 32 37 41

45 50 55 59 63 71 119 128 146 161 180 194

Variable Speed Pumping

Variable water flow involves changing the water flow through the evaporator as the load changes. McQuay chillers are designed for this duty provided that the rate of change in water flow is slow and the minimum and ma xi mum fl o w r at es f or t he ves s el are not exceeded.

The recommended maximum change in water flow is 10 percent of the change per minute.

The water flow through the vessel must remain above the values listed on Table 9. If flow drops below the minimum allowable, large reductions in heat transfer can occur.

Water Piping

Local authorities can supply the installer with the proper building and safety codes required for safe and proper installation.

Install piping with minimum bends and changes in elevation to minimize pressure drop. The following issues must be considered when designing and installing water piping:

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

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

3. Manual or automatic air vent valves at the high points of the system. Drains must be installed at the lowest points in the system.

4. Adequate water pressure must be maintained (expansion tank or regulating valve).

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

6. A strainer or other means of removing foreign matter from the water before it enters the pump must prevent cavitation at the pump inlet (consult pump manufacturer for recommendations). The use of a strainer will prolong pump life and keep system performance up.

7. Flush the system water piping thoroughly before making connections to the unit evaporator. Be sure to install a strainer (40-mesh for models AGZ 010 through 070 and 20-mesh for AGZ 075 through 130) in the return water line before the inlet to the chiller. Design the water piping so the chilled water circulating pump discharges into the evaporator inlet.

8. The unit’s evaporator has a thermostat and heater to prevent freeze-up down to 20°F (-29°C). The heating cable can be wired to a separate 115V supply circuit. As shipped from the factory, the heating cable is wired to the control circuit. All water piping to the unit must also be protected to prevent freezing.

be installed. Place the strainer far enough upstream to

IMM AGZ-7 AGZ 026B through 130B 17

CAUTION

If separate disconnect is used for the 115V supply to the evaporator heating

cable, mark the disconnect clearly to ensure the disconnect is not accidentally

shut off during cold seasons causing a possible damaging evaporator freeze-up.

9. If the unit is used as a replacement chiller, flush the system thoroughly before unit installation. Regular water analysis and chemical water treatment for the evaporator loop is recommended immediately at equipment start-up.

10. The total water volume in the system should be sufficient to prevent frequent “onoff” cycling. Turnover rate should not be less than 4 minutes for normal variable cooling loads.

11. When glycol is added to the water system for freeze protection, the refrigerant suction pressure will be lower, cooling performance less, and water side pressure drop greater. If the percentage of glycol is high, or if propylene is used instead of ethylene glycol, the added pressure drop and loss of performance could be substantial. When Glycol or Ice are selected as Unit Mode, the MicroTech II will automatically reset the available range for the Leaving Water Temperature, Freezestat and Evaporator Pressure settings.

12. Reset the freezestat setting to approximately 4 to 5 degrees F (2.3 to 2.8 degrees C) below the leaving chilled water setpoint temperature. See the section titled “Glycol Solutions” for additional information concerning glycol.

13. Perform a preliminary leak check before insulating the piping and filling the system.

14. Piping insulation should include a vapor barrier to prevent condensation and possible damage to the building structure.

Figure 16, AGZ 075 – AGZ 130, Typical Field Evaporator Water Piping

THERMOWELL

INLET

18 AGZ 026B through 130B IMM AGZ-7

Figure 17, AGZ 026 - AGZ 070, Typical Field Evaporator Water Piping

Air

Inlet

Outlet

Thermowell

Vent

Drain

Vibration

Eliminators

40-Mesh Strainer

Isolation

Valves

Flow

Switch

NOTE: Outdoor piping must be protected if freezing temperatures are a possibility.

Flow Switch

Mount a water flow switch in the leaving water line to shut down the unit when water flow is interrupted. A flow switch is an equipment protection control and should never be used to cycle a unit.

A “paddle” type flow switch is available from McQuay (part number 017503300). Certain minimum flow rates are required to close the switch and are listed in Table 10 on page 19.

Installation should be as shown in Figure 18. Connect the normally open contacts of the flow switch in the unit control center at terminals 44 and 61. There is also a set of normally closed contacts on the switch that can be used for an indicator light or an alarm to indicate when a “no flow” condition exists. Freeze protect any flow switch that is installed outdoors. Manufacturer’s instructions included with the switch should be followed.

NOTE: Differential pressure switches are not recommended for outdoor installation. They can freeze and not indicate a no-flow condition.

Table 10, Flow Switch Minimum/Maximum Flow Rat es

Nominal Pipe Size

Inches (mm)

2 (50.8) 13.7 (51.8) 105 (397.4)

2 1/2 (63.50 17.9 (67.8) 149 (564.0)

3 (76.20 24.2 (91.6) 230 (870.6) 4 (101.6) 35.3 (134.0) 397 (1502.7) 5 (127.0) 48.6 (184.0) 654 (2475.4) 6 (152.4) 60.3 (228.0) 900 (3406.5)

Note: See pressure drop table on page 21 for minimum and maxim um flow through the evaporator.

Minimum Required Flow To

Activate Switch - gpm (l/m)

Maximum Safe Flow Rate

gpm (l/m)

Figure 18, Flow Switch Instal lation

Flow direction marked on switch

1" (25mm) NPT flow switch

connection

Tee

IMM AGZ-7 AGZ 026B through 130B 19

Water Connections

Bring water piping to the evaporator through the side between the vertical supports. Provide taps for the connection of pressure gauges and thermometers in the inlet and outlet lines. Check the inlet and outlet labels on the unit against the certified drawings supplied on the job and be sure the water piping is hooked up correctly. Contact the McQuay sales office if any discrepancies exist.

System Water Volume Considerations

All chillers need adequate time to recognize a load change, respond to the change and stabilize without short cycling the compressor. The water volume in the system and the size of the piping loop is a critical consideration. Good engineering practice is to have a minimum water volume of four times the flow rate (GPM) for comfort cooling applications. For process applications where the load can change quickly, contact the local McQuay sales office for recommendations. A water storage tank (provided by others) may be required to increase the system water volume in some systems.

Since there are many other factors that can influence performance, systems can successfully operate below these suggestions. However, as the water volume decreases below these suggestions, the possibility of problems increases. We believe that these guidelines should be an industry standard and not just recommendations from McQuay.

Variable Speed Pumping

Variable water flow involves reducing the water flow through the evaporator as the load decreases. McQuay chillers are designed for this duty provided that the rate of change in water flow is not greater than 10 percent of the change per minute.

The water flow through the vessel must remain above the values shown on Table 9 on page 17. If flow drops below the minimum allowable, large reductions in heat transfer can occur.

Glycol Solutions

The use of a glycol/water mixture in the evaporator to prevent freezing will reduce system capacity and efficiency, as well as increase pressure drop. The system capacity, required glycol solution flow rate, and pressure drop with glycol may be calculated using the following formulas and tables.

1. Capacity – Multiply the capacity based on water by the Capacity correction factor

from Table 11 through Table 14.

2. Flow – Multiply the water evaporator flow by the Flow correction factor from

Table 11 through Table 14 to determine the increased evaporator flow due to glycol.

If the flow is unknown, it can be calculated from the following equation:

)(24

CapacitykW

elta

18.4

−×

For Metric Applications

(gpm) Flow Glycol FactorCorrectionFlow

– Use the following equation for metric applications:

(l/s) Flow Glycol

3. Pressure drop -- Multiply the water pressure drop from page 25 by Pressure Drop

correction factor from Table 11 through Table 14. High concentrations of propylene glycol at low temperatures may cause unacceptably high pressure drops.

4. Power -- Multiply the water system power by Power correction factor from Table

11 through Table 14.

glycolCapacityTons

TDelta

−

FactorCorrectionFlow

)

20 AGZ 026B through 130B IMM AGZ-7

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. It is recommended that a minimum of 25% solution by weight be used for protection against corrosion or that additional compatible inhibitors be added.

Concentrations above 35 percent do not provide any additional burst protection and should be carefully considered before using.

CAUTION

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 11, Et hyl ene Glycol Factors for Models AGZ 026B to 070B

% E.G.

10 26 -3.3 0.998 0.998 1.036 1.097 20 18 -7.8 0.993 0.997 1.060 1.226 30 7 -13.9 0.987 0.995 1.092 1.369 40 -7 -21.7 0.980 0.992 1.132 1.557 50

Freeze Point

-28 -33.3 0.973 0.991 1.182 1.791

Capacity Power Flow PD

Table 12, Propylene Glycol Factors for Models AGZ 026B to 070B

% P.G.

10 26 -3.3 0.995 0.997 1.016 1.100 20 19 -7.2 0.987 0.995 1.032 1.211 30 9 -12.8 0.978 0.992 1.057 1.380 40 -5 -20.6 0.964 0.987 1.092 1.703 50

Freeze Point

-27 -32.8 0.952 0.983 1.140 2.251

Capacity Power Flow PD

Table 13, Ethylene Glycol Factors for Models AGZ 075B to 130B

% E.G.

10 26 -3.3 0.994 0.998 1.038 1.101 20 18 -7.8 0.982 0.995 1.063 1.224 30 7 -13.9 0.970 0.992 1.095 1.358 40 -7 -21.7 0.955 0.987 1.134 1.536 50

Freeze Point

-28 -33.3 0.939 0.983 1.184 1.755

Capacity Power Flow PD

Table 14, Propylene Glycol Factors for Models AGZ 075B to 130B

% P.G.

10 26 -3.3 0.988 0.996 1.019 1.097 20 19 -7.2 0.972 0.992 1.035 1.201 30 9 -12.8 0.951 0.987 1.059 1.351 40 -5 -20.6 0.926 0.979 1.095 1.598 50

Freeze Point

-27 -32.8 0.906 0.974 1.142 2.039

Capacity Power Flow PD

IMM AGZ-7 AGZ 026B through 130B 21

Altitude Correction Factors

Performance tables are based at sea level. Elevations other than sea level affect the performance of the unit. The decreased air density will reduce condenser capacity consequently reducing the unit's performance. For performance at elevations other than sea level, refer to Table 15 or Table 16.

Evaporator Temperature Drop Factors

Performance tables are based on a 10-degree F (5-degree C) temperature drop through the evaporator. Adjustment factors for applications with temperature ranges from 6 to 16-degree F (3.3 to 8.9-degree C) are in Table 15 or Table 16.

Temperature drops outside this 6 to 16-degree F (3.3 to 8.9-degree C) range can affect the control system's capability to maintain acceptable control and are not recommended.

The maximum water temperature that can be circulated through the evaporator in a non-operating mode is 100°F (37.8°C).

Fouling Factor

Performance tables are based on water with a fouling factor of

As fouling is increased, performance decreases. For performance at other than 0.0001 (0.0176) fouling factor, refer to Table 15 or Table 16.

Foreign matter in the chilled water system will adversely affect the heat transfer capability of the evaporator and could increase the pressure drop and reduce the water flow. Maintain proper water treatment to provide optimum unit operation.

)/0176.0(/0001.0

kWCmorBTUFhrft °×°×× per ARI 550/590-98.

Table 15, Capacity and Power Derates, Models AGZ 026B to 070B

Fouling Factor

Altitude

Sea

Level

2000 feet

610 meters

4000 feet

1220 meters

6000 feet

1830 meters

Chilled Water

Delta T

°F °C Cap. Power Cap. Power Cap. Power Cap. Power

6 3.3 0.978 0.993 0.975 0.991 0.963 0.987 0.940 0.980

8 4.4 0.989 0.996 0.986 0.994 0.973 0.990 0.950 0.983 10 5.6 1.000 1.000 0.996 0.999 0.984 0.994 0.961 0.987 12 6.7 1.009 1.003 1.005 1.001 0.993 0.997 0.969 0.990 14 7.7 1.018 1.004 1.014 1.003 1.002 0.999 0.978 0.991 16 8.9 1.025 1.007 1.021 1.006 1.009 1.001 0.985 0.994

6 3.3 0.977 1.001 0.973 1.000 0.961 0.996 0.938 0.989

8 4.4 0.987 1.006 0.984 1.004 0.971 1.000 0.948 0.993 10 5.6 0.998 1.009 0.995 1.007 0.982 1.003 0.959 0.996 12 6.7 1.007 1.011 1.004 1.010 0.991 1.006 0.967 0.998 14 7.7 1.014 1.014 1.011 1.013 0.998 1.009 0.974 1.001 16 8.9 1.022 1.016 1.018 1.014 1.005 1.010 0.981 1.003

6 3.3 0.973 1.011 0.970 1.010 0.957 1.006 0.935 0.998

8 4.4 0.984 1.014 0.980 1.013 0.968 1.009 0.945 1.001 10 5.6 0.995 1.019 0.991 1.017 0.979 1.013 0.955 1.005 12 6.7 1.004 1.021 1.000 1.020 0.987 1.016 0.964 1.008 14 7.7 1.011 1.024 1.007 1.023 0.994 1.018 0.971 1.011 16 8.9 1.018 1.027 1.014 1.026 1.002 1.021 0.978 1.014

6 3.3 0.969 1.021 0.966 1.020 0.954 1.016 0.931 1.008

8 4.4 0.980 1.026 0.977 1.024 0.964 1.020 0.942 1.013 10 5.6 0.989 1.029 0.986 1.027 0.973 1.023 0.950 1.015 12 6.7 0.998 1.033 0.995 1.031 0.982 1.027 0.959 1.020 14 7.7 1.007 1.036 1.004 1.034 0.991 1.030 0.967 1.022 16 8.9 1.014 1.037 1.011 1.036 0.998 1.031 0.974 1.024

0.0001 (0.0176) 0.00025 (0.044) 0.00075 (0.132) 0.00175 (0.308)

22 AGZ 026B through 130B IMM AGZ-7

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