McQuay AGZ 035A Installation, Operation And Maintenance Manual
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McQuay AGZ 035A Installation, Operation And Maintenance Manual

Air-cooled scroll compressor chiller 60 hertz, r-22
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Installation, Operation and Maintenance Manual
Air-Cooled Scroll Compressor Chiller
AGZ 035A through 065A
60 Hertz, R-22
Global Chiller Line
IOMM AGZ-3
Group: Chiller
Part Number: 074641003
Effective: June 2002
Supercedes: IOMM AGZ-2

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  • Page 1 Installation, Operation and Maintenance Manual IOMM AGZ-3 Group: Chiller Part Number: 074641003 Effective: June 2002 Supercedes: IOMM AGZ-2 Air-Cooled Scroll Compressor Chiller AGZ 035A through 065A 60 Hertz, R-22 Global Chiller Line...

  • Page 2: Table Of Contents

    "McQuay" is a registered trademark of McQuay International  2002 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" AGZ 035A through 065A...

  • Page 3: Introduction

    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 unit leaves the factory.

  • Page 4: Installation

    Figure 2, Suggested Lifting Arrangement Number of fans may vary from this diagram. The Spreader Bars lifting method will remain recommended the same (use caution) These rigging holes must be used. AGZ 035A through 065A IOMM AGZ-3...

  • Page 5: Location

    MicroTech controller. Low pressure, and motor protector controls are on the compressor. Most other operational, equipment protection and starting controls are located in the unit control box. The condenser fan and motors can be removed from the top of the unit. IOMM AGZ-3 AGZ 035A through 065A...
  • Page 6 Figure 3, Clearance Requirements AGZ 035A through 065A IOMM AGZ-3...

  • Page 7: Vibration Isolators

    Table 1 and Table 2 list isolator point loads for all unit sizes. Figure 4 shows isolator locations. See Dimensional Data for detailed dimensions required to secure each isolator to the mounting surface. The spring flex isolators are white type CP2-32, McQuay kit number 350014821 provides the required four per unit.

  • Page 8: Water Piping

    12. Perform a preliminary leak check before insulating the piping and filling the system. 13. Piping insulation should include a vapor barrier to prevent condensation and possible damage to the building structure. AGZ 035A through 065A IOMM AGZ-3...

  • Page 9: Flow Switch

    A flow switch is an equipment protection control and should never be used to cycle a unit. A flow switch is available from McQuay (part number 017503300). It is a “paddle” type switch and adaptable to any pipe size from 3” (76mm) to 8” (203mm) nominal. Certain minimum flow rates are required to close the switch and are listed in Table 3.

  • Page 10: Water Connections

    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. AGZ 035A through 065A IOMM AGZ-3...

  • Page 11: Evaporator Flow And Pressure Drop

    Measure the chilled water pressure drop through the evaporator at factory installed pressure taps. It is important not to include the effect of valves or strainers in these readings. Varying chilled water flow through the evaporator while the compressor(s) are operating is not recommended. IOMM AGZ-3 AGZ 035A through 065A...
  • Page 12 45.0 14.51 5.44 065AS 10.0 9.21 25.1 15.35 5.76 Minimum and maximum flows are established to ensure the Delta-T for each unit size falls within the 6 - 16°F range for proper unit control. AGZ 035A through 065A IOMM AGZ-3...

  • Page 13: Physical Data

    NOTES: Nominal capacity based on 95°F ambient air and 54°F/44°F water range. Units with 1.0 Hp Fan Motors, Uses 1.5 Hp Fan Motors when unit is 380V / 60 Hz and 575V / 60Hz. IOMM AGZ-3 AGZ 035A through 065A...
  • Page 14 .375 (9.5) .375 (9.5) .375 (9.5) .375 (9.5) Vent - NPT int, In. (mm) .375 (9.5) .375 (9.5) .375 (9.5) .375 (9.5) NOTE: Nominal capacity based on 95°F ambient air and 54°F/44°F water range. AGZ 035A through 065A IOMM AGZ-3...

  • Page 15: Electrical Data

    If the evaporator heater is on a separate disconnect switch from the main unit power supply, the unit may be shut down without defeating the freeze protection provided by the cooler heater. Table 9, AGZ 035A - 065A, 60 Hz, Single Point Power Electrical Data POWER SUPPLY Max. Fuse...
  • Page 16 Table 10, AGZ 035A - 065A, 60 Hz, Compressor and Condenser Fan Motor Amp Draw Rated Load Amps Locked Rotor Amps Compressors Compressors No. Of Across-The-Line Unit Volts Motors Motors Size Motors 1 & 3 2 & 4 No.1 & 3 No.2 &...
  • Page 17 Requires a single disconnect to supply electrical power to the unit. This power must be fused. All field wiring to unit power block or optional non-fused disconnect switch must be copper. All field wire size values given in table apply to 75°C rated wire per NEC. IOMM AGZ-3 AGZ 035A through 065A...
  • Page 18 Electrical Legend Figure 8, Electrical Legend AGZ 035A through 065A IOMM AGZ-3...
  • Page 19 Figure 9, Typical Field Wiring with Global UNT Controller IOMM AGZ-3 AGZ 035A through 065A...
  • Page 20 Figure 10, Typical Field Wiring Diagram with MicroTech Controller AGZ 035A through 065A IOMM AGZ-3...
  • Page 21 Figure 11, Single-point Connection with FanTrol IOMM AGZ-3 AGZ 035A through 065A...
  • Page 22 Figure 12, Single-point Connection with SpeedTrol AGZ 035A through 065A IOMM AGZ-3...
  • Page 23 Figure 13, Unit Control Schematic (UNT) IOMM AGZ-3 AGZ 035A through 065A...
  • Page 24 Figure 14, Staging Schematic (UNT) AGZ 035A through 065A IOMM AGZ-3...
  • Page 25 Figure 15, MicroTech Controller Schematic IOMM AGZ-3 AGZ 035A through 065A...
  • Page 26 Figure 16, Unit Control Schematic (MicroTech) AGZ 035A through 065A IOMM AGZ-3...
  • Page 27 Figure 17, Staging Schematic (MicroTech) IOMM AGZ-3 AGZ 035A through 065A...

  • Page 28: Dimensional Data

    Dimensional Data Figure 18, Dimensions AGZ 035A - 065A Dimensions Center Of Gravity Unit Weights Additional Weight inches (mm) inches (mm) lb (kg) Model For Copper Number Fin Coils lb (kg) Operating Shipping 86.2 81.7 61.6 22.3 15.0 43.9 40.2 36.2...

  • Page 29: Startup

    Be prepared to record all operating parameters required by the “Compressorized Equipment Warranty Form”. Return this information within 10 working days to McQuay International as instructed on the form to obtain full warranty benefits.

  • Page 30: Water Piping Checkout

    7. Leak detector is applied externally to refrigerant joints at the factory. Do not confuse this residue with an oil leak. 8. Connect refrigerant service gauges to each refrigerant circuit before starting unit. AGZ 035A through 065A IOMM AGZ-3...

  • Page 31: Electrical Check Out

    10. Check between TB-3 terminal #17 and #27 for 24Vac control voltage. 11. Check on the Global UNT controller between terminals marked 24Vac and common for 24Vac control voltage. Green light on Global UNT controller should be flashing. IOMM AGZ-3 AGZ 035A through 065A...

  • Page 32: Operation

    Unoccpd Lvg SP 70°F 40 to 90°F OA Lockout SP -10°F -20 to 65°F Lvg Low Lim SP 20°F 20 to 40°F SoftSta Capcty 0 to 100% SoftStart Time 2 min 0 to 20 minutes AGZ 035A through 065A IOMM AGZ-3...

  • Page 33: Hot Gas Bypass (Optional)

    The bulb has to have a stable ambient air temperature for proper operation. Placing the bulb in contact with the evaporator refrigerant line will limit the operation of the hot gas bypass valve. IOMM AGZ-3 AGZ 035A through 065A...

  • Page 34: Filter Driers

    The power element is removable from the valve body without removing the valve from the line. AGZ 035A through 065A IOMM AGZ-3...

  • Page 35: Crankcase Heaters

    The water connection nozzles which enter and leave the shell are on the same side of the unit. No special attention is required for the cooler except that clean, filtered water should be supplied. IOMM AGZ-3 AGZ 035A through 065A...

  • Page 36: Global Unt Controller Installation And Operation

    All interlock wiring to field devices (such as a flow switch or time clock) is provided by the installing contractor. All interlocking wiring must be connected to the Global UNT 24Vac power supply. External power supplies connected to the Global UNT controller can damage the controller. See unit wiring diagram. AGZ 035A through 065A IOMM AGZ-3...
  • Page 37 If remote stop/start control is selected, remove the jumper between terminals #140 and #141 on TB-7 and install the input between these terminals. When the remote stop/start switch is open, the controller will be in the unoccupied mode. IOMM AGZ-3 AGZ 035A through 065A...

  • Page 38: Controller Inputs /Outputs

    10 to 60° F ( -12 to 15°C) AI-5 Circuit #2 Evap Pressure Circuit #2 Suction Line 0 to 150 psi (0 - 1034kPa) AI-6 Control Band Setpoint Dial Control Panel 0 to 10°F (-17 to -12°C) AGZ 035A through 065A IOMM AGZ-3...
  • Page 39 Outdoor Air High High Limit (OAHL), and Outdoor Air Reset Band (OARB). Figure 19, Outside Air Reset LW RB LW SP OA LL O AH L O A R B (O A LL= O AH L - O A R B ) IOMM AGZ-3 AGZ 035A through 065A...
  • Page 40 Actual Leaving Water Setpoint. These are: Leaving Water Dial Setpoint (AI-4), Reset Band SP selected with the Zone Terminal, Zone Temperature High Limit (ZTHL), and Zone Temperature Reset Band (ZTRB). AGZ 035A through 065A IOMM AGZ-3...
  • Page 41 (0 to 100%). At 0Vdc signal input, the controller does not limit compressor staging. At 10Vdc signal input, the chiller would be off. Between 0Vdc and 10Vdc, a proportional percentage capacity is available. IOMM AGZ-3 AGZ 035A through 065A...

  • Page 42: Additional Global Unt Features

    The second stage of cooling will be the first compressor of the lag refrigerant circuit. Cooling stage three will always be compressor #3 and cooling stage four will always be compressor #4. Stage down is the reverse of the above paragraph. AGZ 035A through 065A IOMM AGZ-3...
  • Page 43 LPHL (low pressure high limit, (default 57psi)) value, the controller stages up on leaving water temperature requirements. If the evaporator pressure is below the LPHL, then the controller will stop that circuit and indicate a freezestat alarm on the (optional) Zone Terminal. IOMM AGZ-3 AGZ 035A through 065A...

  • Page 44: Alarms

    The chiller must have the manual reset system alarm conditions cleared before normal operation can resume. If the alarm that occurred is an auto-clearing alarm, once the condition has corrected, the chiller will resume normal operation provided the anti-cycle timers have cleared and sufficient load exists. AGZ 035A through 065A IOMM AGZ-3...

  • Page 45: Zone Terminal (Optional)

    Zone Terminal (Optional) The Zone Terminal (ZT) is a hand-held or unit mounted device that monitors and adjusts your McQuay Global Scroll Chiller information. A standard telephone-style jack directly connects the ZT to the McQuay Global UNT controller. Features •...

  • Page 46: Operating Modes

    Monitor Mode lets you view up to three of chiller settings/sensed values at a time. To allow you to monitor your system, a clear plastic Insert (factory made and installed) relates the ZT’s output to your McQuay Global UNT controller. You can simultaneously monitor the chiller in three ways: •...
  • Page 47 3. Press the ZT together. With the Insert in place and the ZT connected, the l in the top position of each display lines up with the first word. Figure 25, Installing the Insert IOMM AGZ-3 AGZ 035A through 065A...
  • Page 48 McQuay Global Scroll Controller Connection A standard telephone-style jack connects the ZT to a McQuay Chiller Controller directly. Figure 26, Connecting ZT to a Global UNT Controller Using 6 to 8 Pin Cable 1 2 3 4 5 6 7 8...

  • Page 49: Zone Terminal Glossary

    Adjustable Points The following McQuay Global Scroll Chiller points are adjustable by the Zone Terminal. Table 16, Adjustable Points TEMPLATE VALUES NAME FACTORY SETPOINT RANGE OA/AI3 HiLim SP 80°F 0 to 100°F OA/AI3 Reset SP -40°F -100 to 100°F LvgWtr Rband SP 0°F...
  • Page 50 Compressor # 1 - Compressor 1 is On or Off Compressor #2 - Compressor 2 is On or Off Stage 3 to 6 - Indicates how many additional compressor (or unloading) stages are on at the time. AGZ 035A through 065A IOMM AGZ-3...

  • Page 51: Unt Troubleshooting Chart

    1. Check for reasons and correct. 2. System load erratic. 2. Check water flow control valve operation. Erratic Loading and 3. Bad water sensor. 3. Replace. Unloading 4. Reset function calibration. 4. Re-calibrate 5. Defective UNT controller. 5. Replace IOMM AGZ-3 AGZ 035A through 065A...

  • Page 52: Microtech Controller Installation And Operation

    Important operating conditions at the time of the alarm are retained in the controller’s memory to aid in troubleshooting and unit diagnostics. McQuay MicroTech Monitor software is available for remote adjustment and monitoring of the chiller.

  • Page 53: Interlock Wiring

    Lead-Lag A feature on all McQuay AGZ 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.

  • Page 54: Chilled Water Flow Switch

    The chilled water flow switch is connected to field wiring terminals #142 and #143 on TB-7. When the chilled water pump is enabled, the MicroTech controller checks for proof-of-flow through the flow switch digital input. AGZ 035A through 065A IOMM AGZ-3...
  • Page 55 Misc. Setup menu. Example of typical software identification: AGZ 2 E 01 A Revision Unit Model Version Refrigerant English or Metric IOMM AGZ-3 AGZ 035A through 065A...
  • Page 56 Alarm Motor Protection Switch Compressor #2 Normal Alarm Motor Protection Switch Compressor #4 Normal Alarm Chiller Remote Stop Switch Unit Stop Evap Water Flow Switch Unit Stop Pumpdown Switch Circuit #2 Pmp Dn Normal AGZ 035A through 065A IOMM AGZ-3...
  • Page 57 When the outside air temperature is above the outside air temperature reset setpoint the leaving water temperature is not reset and is controlled to the leaving water temperature setpoint. IOMM AGZ-3 AGZ 035A through 065A...
  • Page 58 (21°F + 2°F = 23°F; 23°F = 46psig) Network A network refers to a McQuay MicroTech control panel (CSC or RMS) that can provide controlling functions to several McQuay chillers. One function is to control the chiller leaving water temperature according to some control logic in the network control panel.

  • Page 59: Manual Operation

    The second fan will cycle on and off to maintain minimum lift pressure. If the condenser pressure increases rapidly, the second fan will be turned on at 290 psig (R- 22 setpoint) and remain on until minimum lift pressure regains control. IOMM AGZ-3 AGZ 035A through 065A...
  • Page 60 Thus, the alarm must be manually cleared. When a McQuay Chiller with a MicroTech controller is used with the McQuay RMS (Remote Monitoring and Sequencing) Panel, the user must note that alarm nomenclature varies. The RMS has three possible categories of alarms: faults, problems, and warnings.

  • Page 61: Sequence Of Operation

    OFF:Remote Sw. The chiller can also be commanded off via the communications network if a separate System Master Panel is installed. The display will show OFF:Remote Comm if this operating mode is in effect. IOMM AGZ-3 AGZ 035A through 065A...
  • Page 62 As the evaporator pressure falls below the LPCutOut set point, the compressor and condenser fan will stop. The evaporator pump output relay will remain energized and the unit status will indicate “Waiting For Load”. AGZ 035A through 065A IOMM AGZ-3...

  • Page 63: Start-Up And Shutdown

    Move both pumpdown switches to the auto position. DH1-7 and DH2-15 will turn off. The controller will then activate one of the refrigerant circuit solenoids depending upon which is the lead circuit. (output relay #4 circuit #1or output relay #5 circuit #2) When the evaporator pressure rises IOMM AGZ-3 AGZ 035A through 065A...

  • Page 64: Keypad / Display

    If external water piping is heat traced, leave the heat tracing power on to protect from freezing. Keypad / Display Figure 27, Keypad / Display AGZ 035A through 065A IOMM AGZ-3...
  • Page 65 Any keypad activity will reset the timer for the full 5 minutes so the password only needs to be entered once per session. After 5 minutes of inactivity, the password access time will expire providing protection against unauthorized users. IOMM AGZ-3 AGZ 035A through 065A...
  • Page 66 N T E R N T E R IncrWhen changing the value of a menu item entry, pressing “INCR. +” shifts the menu item display line to the next higher or next available selection. AGZ 035A through 065A IOMM AGZ-3...

  • Page 67: Menu Descriptions

    Menu #5: Circuit #l PressuresThe circuit #l evaporator and condenser refrigerant pressure readings are displayed under this menu. The calculated minimum and maximum condenser pressure values are also shown. IOMM AGZ-3 AGZ 035A through 065A...
  • Page 68 Maximum Chilled Water Reset set point ("MaxChWRst"). At 4ma or less, no reset will occur. At 20ma, the chilled water set point will be reset AGZ 035A through 065A IOMM AGZ-3...
  • Page 69 1, the unit will shut completely off once the leaving chilled water temperature has reached the Leaving Chilled Water Set Point minus half of the Control Band minus the Shut Down Delta-T. IOMM AGZ-3 AGZ 035A through 065A...
  • Page 70 The cursor will advance to the Date position on the display that can be set in the same manner. After pressing the Enter key to set the Date, the cursor will advance to the Year position on the display. Use the Incr, Decr, and Enter keys to set the correct Year. AGZ 035A through 065A IOMM AGZ-3...
  • Page 71 Menu #27: Circuit #2 Previous Alarm—The alarm type for the last recorded circuit #2 alarm can be displayed from this menu. The time and date at which the previous alarm occurred are also displayed here. This information will be replaced when a current alarm condition is cleared. IOMM AGZ-3 AGZ 035A through 065A...
  • Page 72 Open N/A ** °F (°C) OFF: PumpDwnSw Short N/A **°F OFF: CycleTime xx MinCondPr = 0# OFF: Ready MaxCondPr = 0# PumpingDown LiftD_P= psi OpenSolenoid Cond Fan Stage = x % Capacity Starting LowAmbStart AGZ 035A through 065A IOMM AGZ-3...
  • Page 73 Table 32, MENU 12 Air Temp N/A **°F (°C) Screen Display Liquid Ln = xxx.x°F (°C) N/A ** °F (°C) OutDoor = xxx.x °F( °C) SubCoolg= xxx.x°F (°C) N/A ** °F (°C) CondD-T °F (°C) IOMM AGZ-3 AGZ 035A through 065A...
  • Page 74 MaxChWRst=xx.x °F (°C) 10.0 (5.5) 0.0 - 45.0 (0.0 - 25.0) ReturnSpt= xx.x °F (°C) 54.0 (12.3) 15.0 - 80.0 (-9.4 - 26.7) [ ] the minus sign is not displayed with three digit numbers AGZ 035A through 065A IOMM AGZ-3...
  • Page 75 Indicates the Magnitude of the DemandSg= xx.x ma Actual Value Demand Limit Signal Table 41, MENU 19 Time / Date Screen Display Factory Setpoint Range Time= xx:xx:xx Actual Time Mon xx/xx/xx Actual Day and Date IOMM AGZ-3 AGZ 035A through 065A...
  • Page 76 4 - 26 (27 - 179) FreezH2O= xx.x °F (°C) 36.0 (2.3) 0.0 - 40.0 (-17.5 - 4.5) FreezeTim= xxx sec Hi Press = xxxpsi (kPa) 380 (2622) 280 - 426 (1932 - 2939) AGZ 035A through 065A IOMM AGZ-3...
  • Page 77 2 x:xx x/xx/xx SuctLine=xxx.x °F(°C) 3 Current Alarm LiquisLn=xxx.x °F(°C) 3 x:xx x/xx/xx Evap Lvg=xxx.x °F(°C) 4 Current Alarm OAT=xx.xx°F(°C) 4 x:xx x/xx/xx Capacity= xxx% 5 Current Alarm Fan Stage = x 5 x:xx x/xx/xx IOMM AGZ-3 AGZ 035A through 065A...

  • Page 78: Trouble Analysis For The Microtech

    MCB power supply circuit. Microprocessor Status LEDs The green, red, and amber LEDs on the MCB provide information about the operating status of the microprocessor. The amber LED also indicates the existence of alarm conditions. AGZ 035A through 065A IOMM AGZ-3...
  • Page 79 If a hex switch setting is changed, power to the MCB must be cycled in order to enter the new setting into memory. This can be done by turning the panel’s power switch off and then back on. IOMM AGZ-3 AGZ 035A through 065A...
  • Page 80 Above each edge card connector are field wiring terminals for 5Vdc (regulated) and 24Vac (ground referenced). These terminals can be used to power peripheral devices. The 5Vdc is also used to power the LEDs in the Output Board. AGZ 035A through 065A IOMM AGZ-3...

  • Page 81: Test Procedures

    5. Reconnect the keypad/display ribbon cable. Cycle power to the controller and check the power fuses. If both fuses are intact, go to step 6. If either fuse blows, check the keypad/display and the connecting ribbon cable for shorts. Either one can be defective. IOMM AGZ-3 AGZ 035A through 065A...
  • Page 82 If the resistance does not rise above 5000 ohms, the modem or the AOX-4 board just connected is defective. (With the power plug disconnected, the resistance across an AOX-4 board’s “DC” and “G” terminals should not be less than 3 million ohms.) AGZ 035A through 065A IOMM AGZ-3...
  • Page 83 Remove power from the controller before disconnecting the suspect component, and restore power after connecting the replacement component. If the problem persists, it is likely that the MCB is defective. IOMM AGZ-3 AGZ 035A through 065A...
  • Page 84 MOVs are part of the output board and cannot be replaced. Following are troubleshooting procedures for various symptoms of output board problems: Note: It should be possible to determine whether a solid-state relay is defective by using these procedures. AGZ 035A through 065A IOMM AGZ-3...
  • Page 85 If 5Vdc is present, check the ribbon cable and connections between the output board and MCB. Look for bent pins. If the cable and connections are intact, the Output Board or the MCB is defective. IOMM AGZ-3 AGZ 035A through 065A...
  • Page 86 Try to choose a relay that will not affect unit operation. Restore power by closing CB1. If the chatter does not stop, go to step 3. If the chatter stops, the suspect relay is defective. Replace the relay. AGZ 035A through 065A IOMM AGZ-3...
  • Page 87 In this situation, an incandescent test lamp is a better tool than a voltmeter. Figure 33, Testing a Typical Relay Circuit 115 VAC Output Board DO 13 Neutral Figure 34, Testing a Relay Circuit with a Disconnection 115 VAC Output Board DO 13 Neutral 115V IOMM AGZ-3 AGZ 035A through 065A...

  • Page 88: Unit Maintenance

    No maintenance is ordinarily required except the routine removal of dirt and debris from the outside surface of the fins. McQuay recommends the use of foaming coil cleaners available at most air conditioning supply outlets. Use caution when applying such cleaners as they can contain potentially harmful chemicals.

  • Page 89: Preventive Maintenance Schedule

    4. Coil cleaning can be required more frequently in areas with a high level of airborne particles. 5. Be sure fan motors are electrically locked out. Never Megger motors while they are in a vacuum. IOMM AGZ-3 AGZ 035A through 065A...

  • Page 90: Service

    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. To replace the entire solenoid valve follow the steps involved when changing a filter-drier. AGZ 035A through 065A IOMM AGZ-3...

  • Page 91: Evaporator

    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. IOMM AGZ-3 AGZ 035A through 065A...
  • Page 92 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. AGZ 035A through 065A IOMM AGZ-3...

  • Page 93: Agz Troubleshooting Chart

    Check supply voltage. Notify power company. Do not start until fault is corrected. Compressor Thermal Operating beyond design conditions Add facilities so conditions are within allowable limits Protection Switch Discharge valve partially shut Open valve Open Blown compressor internal gasket Replace gasket IOMM AGZ-3 AGZ 035A through 065A...
  • Page 94 Notes AGZ 035A through 065A IOMM AGZ-3...
  • Page 96 This document contains the most current product information as of this printing. For the most up-to- date product information, please go to www.mcquay.com. Post Office 2510, Staunton, Virginia 24402 USA • (800) 432-1342 • www.mcquay.com...

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