McQuay AGZ 035A, Installation, Operation And Maintenance Manual

Page 1: ...peration 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...

Page 2: ...ontroller Installation and Operation 36 General Description 36 Optional Sensors 36 Controller Inputs Outputs 38 Additional Global UNT Features 42 Alarms 44 Zone Terminal Optional 45 Zone Terminal Glos...

Page 3: ...lag switch to alternate the compressor starting sequence and sequenced starting of compressors The electrical control center includes all equipment protection and operating controls necessary for dep...

Page 4: ...he 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 holes are provided in the base...

Page 5: ...compressors electrical control panel and piping components as shown in Figure 3 Do not allow debris to accumulate near the unit Air movement may draw debris into the condenser coil causing air starva...

Page 6: ...6 AGZ 035A through 065A IOMM AGZ 3 Figure 3 Clearance Requirements...

Page 7: ...lb Kg lb Kg lb Kg lb Kg 035AS 850 386 960 435 785 356 885 401 3480 1579 040AS 864 392 974 442 797 362 900 408 3535 1603 045AS 928 421 1048 475 858 389 966 438 3800 1724 050AS 940 426 1062 482 868 394...

Page 8: ...vent freeze up down to 20 F 29 C It is suggested that the heating cable be wired to a separate 110V supply circuit As shipped from the factory the heating cable is wired to the control circuit All wat...

Page 9: ...d be as shown in Figure 6 Connect the normally open contacts of the flow switch in the unit control center at terminals 5 and 6 There is also a set of normally closed contacts on the switch that can b...

Page 10: ...plications Factor Correction Flow T Delta Capacity kW 18 4 l s Flow Glycol 3 Pressure drop Multiply the water pressure drop from Figure 7 by Pressure Drop correction factor from Table 4 or Table 5 to...

Page 11: ...984 10 5 6 0 986 1 009 0 979 1 007 0 956 1 000 0 914 0 986 12 6 7 0 992 1 011 0 985 1 009 0 962 1 002 0 919 0 988 14 6 8 0 997 1 014 0 990 1 012 0 967 1 005 0 924 0 991 2000 feet 610 m 16 8 9 1 000 1...

Page 12: ...9 2 82 5 17 23 1 137 8 62 3 9 51 3 23 040AS 11 5 93 5 87 28 8 155 9 78 4 9 58 3 67 045AS 11 2 106 6 69 28 2 177 11 15 4 8 66 4 18 050AS 13 4 117 7 38 33 6 195 12 30 5 7 73 4 61 055AS 16 2 129 8 14 40...

Page 13: ...ERS HIGH EFFICIENCY FIN AND TUBE TYPE WITH INTEGRAL SUBCOOLING Coil Face Area sq ft 46 4 46 4 46 4 46 4 46 4 46 4 Coil Face Area m 2 4 3 4 3 4 3 4 3 4 3 4 3 Finned Height x Finned Length In 80 x 83 5...

Page 14: ...5 50 75 100 0 25 50 75 100 CONDENSERS HIGH EFFICIENCY FIN AND TUBE TYPE WITH INTEGRAL SUBCOOLING Coil Face Area sq ft 46 4 46 4 46 4 46 4 46 4 46 4 58 0 58 0 Coil Face Area m2 4 3 4 3 4 3 4 3 4 3 4 3...

Page 15: ...y the cooler heater Table 9 AGZ 035A 065A 60 Hz Single Point Power Electrical Data POWER SUPPLY Field Wire Hub AGZ Unit Size Volts Minimum Circuit Ampacity MCA Quantity Wire Gauge Quantity Nominal Siz...

Page 16: ...3 7 350 425 230 41 5 52 8 5 8 4 23 7 350 425 380 28 0 32 7 3 4 4 14 4 195 239 460 21 8 23 7 2 8 4 10 7 158 187 055A 575 17 3 22 1 2 3 4 11 5 125 148 208 52 8 52 8 5 8 4 23 7 425 425 230 52 8 52 8 5 8...

Page 17: ...Therefore it is recommended that power leads be kept short All terminal block connections must be made with copper type THW wire 5 Recommended Fuse Sizes are selected at approximately 150 to 175 of th...

Page 18: ...18 AGZ 035A through 065A IOMM AGZ 3 Electrical Legend Figure 8 Electrical Legend...

Page 19: ...IOMM AGZ 3 AGZ 035A through 065A 19 Figure 9 Typical Field Wiring with Global UNT Controller...

Page 20: ...20 AGZ 035A through 065A IOMM AGZ 3 Figure 10 Typical Field Wiring Diagram with MicroTech Controller...

Page 21: ...IOMM AGZ 3 AGZ 035A through 065A 21 Figure 11 Single point Connection with FanTrol...

Page 22: ...22 AGZ 035A through 065A IOMM AGZ 3 Figure 12 Single point Connection with SpeedTrol...

Page 23: ...IOMM AGZ 3 AGZ 035A through 065A 23 Figure 13 Unit Control Schematic UNT...

Page 24: ...24 AGZ 035A through 065A IOMM AGZ 3 Figure 14 Staging Schematic UNT...

Page 25: ...IOMM AGZ 3 AGZ 035A through 065A 25 Figure 15 MicroTech Controller Schematic...

Page 26: ...26 AGZ 035A through 065A IOMM AGZ 3 Figure 16 Unit Control Schematic MicroTech...

Page 27: ...IOMM AGZ 3 AGZ 035A through 065A 27 Figure 17 Staging Schematic MicroTech...

Page 28: ...5 40 2 1021 36 2 920 3535 1605 3460 1570 445 200 045AS 86 2 2190 81 7 2075 61 6 1565 22 3 566 4 3 108 16 0 406 44 2 1123 40 8 1036 35 6 904 3800 1725 3695 1675 445 200 050AS 86 2 2190 81 7 2075 61 6 1...

Page 29: ...e control band before the Global UNT controller will stage on cooling 4 Set the control band to 4 F as a starting point 5 Put both circuit switches to the AUTO position 6 Put switch S1 to AUTO positio...

Page 30: ...o start the chiller after an extended shutdown follow the pre startup and startup instructions Water Piping Checkout 1 Check the pump operation and vent all air from the system 2 Circulate evaporator...

Page 31: ...Emergency Stop position 4 Put both circuit 1 2 switches to the Pumpdown and Stop position 5 Apply power to the unit The panel Alarm Light will stay on until S1 is closed Ignore the Alarm Light for the...

Page 32: ...l be energized and if the evaporator pressure is above the LPSS low pressure starting setpoint relay BO7 will be energized starting Compressor 1 and energizing the liquid line solenoid valve SV1 throu...

Page 33: ...t is supplied can provide a load of approximately 10 tons The system load added to the ten tons of the hot gas bypass valve has to exceed the compressor capacity for stage 1 compressors for stable sys...

Page 34: ...ly important when the system has been serviced Immediately after the system has been opened for service the element may indicate a wet condition It is recommended that the equipment operate for about...

Page 35: ...p level The function of the heater is to keep the temperature in the crankcase high enough to prevent refrigerant from migrating to the crankcase and condensing in the oil during off cycle Power must...

Page 36: ...fittings and can be replaced without pumping the unit down The pressure transducers are connected to the Global UNT controller analog inputs with IDC connectors Insulation Displacement Connectors The...

Page 37: ...r heater power source 120Vac is supplied from a separate external supply remove wires 540 and 545 as indicated on the unit wiring diagram Power Supplies There are several internal power supplies used...

Page 38: ...Note The alarm signal is not active during a power failure and will not provide a Loss of Power alarm PC Connection The Global UNT controller can be connected to an IBM or IBM compatible computer for...

Page 39: ...d Line Solenoid Valve 2 Circuit 2 Liquid Line Solenoid Valve 3 Compressor 3 Contactor M3 4 Compressor 4 Contactor M4 5 Spare 6 Spare 7 Low Pressure Relay Circuit 1 8 Low Pressure Relay Circuit 2 Reset...

Page 40: ...Limit Leaving Water Setpoint plus Leaving Reset Band to the Leaving Water Setpoint When RWT reaches the RWHL the Actual Leaving Water Setpoint equals the Leaving Water Setpoint AI 4 If the RWT sensor...

Page 41: ...X SW1 Off V X X X X Remote Reset 2 to 10VDC input When selected a 2 to 10Vdc signal is connected to TB 7 terminals 134 and 135 This input can be achieved by using a 4 20ma signal and conditioning it...

Page 42: ...e Soft Start Capacity The duration of the soft load sequence is determined by the Soft Start Timer If the Soft Start Timer is set to zero no soft loading will take place The Zone Terminal is required...

Page 43: ...stage up as additional cooling is required If the evaporator pressure is less than the LPHL the Global UNT controller will de energize BO7 or BO8 depends on circuit starting which will stop the compr...

Page 44: ...r protection occurrence Freeze protection would be indicated on the optional Zone Terminal If a circuit is off and the panel alarm light is not on try depressing the Freezestat reset on the control pa...

Page 45: ...ttings Figure 24 Zone Terminal MONITOR ADJUST TIME SCHEDULE PASSWORD ENTER Compressor 1 Compressor 2 Stage 3 Stage 4 Solenoid 1 Frzstat 1Alm Frzstat 2Alm MinLowPres 1 MinLowPres 2 Occupied Flow Failur...

Page 46: ...ch of the three displays Read the symbols to the right of the display numbers to learn the on off status of various inputs outputs or modes On status m Off status This provides continuous monitoring o...

Page 47: ...point in the HVAC controller with these symbols A bar for On a circle m for Off These are always monitor only items If the symbol flashes item is in alarm Red Alarm Light Flashes anytime a problem ex...

Page 48: ...he right of the Mode Selector Panel flashes when any of the above items are in alarm Alarms cannot be cleared with the ZT The problem must be corrected by maintenance or repair of the affected item MA...

Page 49: ...in algorithm for Outside Air Reset For an example of 10 F reset 45 F Leaving Water Setpoint reset up to 55 F Contrl Band SP Indicates what the Control Band Knob is set at Non adjustable from ZT Actual...

Page 50: ...e Freez Stat Reset button located on the Control Panel must be pushed once to clear Frzstat 2Alm If circuit 2 fails on freeze the alarm light on the ZT will light To clear the alarm the Freez Stat Res...

Page 51: ...UNT controller Replace if defective 3 Replace compressor 4 Check reasons for high condenser pressure Low Suction Pressure 1 Low refrigerant charge 2 Defective expansion valve 3 Dirty filter drier 4 Re...

Page 52: ...kage Suction line temperature circuit 1 Suction line temperature circuit 2 Liquid line temperature circuit 1 Liquid line temperature circuit 2 Unit amp package Unit amperage Percent total unit amperag...

Page 53: ...starting the unit For more information on menu items see the menu description section Modem kit An optional modem kit allowing remote monitoring of the chiller from an off site PC running McQuay Moni...

Page 54: ...available for the alarm bell option Wire according to the field wiring diagram Analog Input Signals All sensors and transducers required for normal chiller operation are installed and wired at the fa...

Page 55: ...alarm condition the alarm circuit will energize and the alarm status light will be on During a pre alarm condition the alarm output and status light will pulse on for one half second and off for four...

Page 56: ...ving Cond Water Temp Leaving Cond Water Nozzle 40 to 263 F 0 1 F 11 11 Total Unit Amps Control Cabinet 0 to 4 VDC 12 12 Circuit 1 Suction Temp Circuit 1 Suction Line 40 to 263 F 0 1 F 13 13 Circuit 2...

Page 57: ...12 12 Spare 13 Condenser Fan M21 14 Condenser Fan M22 15 Spare Reset Options User reset options are located in the Leaving Water Setpoint menu The options are None None is the default value and the le...

Page 58: ...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...

Page 59: ...quipment protection control the number of cooling stages will be decreased and always equal to the number of available compressors for operation At all times the second stage of cooling will have a co...

Page 60: ...seconds off When an alarm of pre alarm condition exists the MicroTech display automatically switches to the alarm menu to alert the user of the condition The MicroTech controller alarms can either be...

Page 61: ...ndition and the MicroTech display will show the current alarm condition System alarm conditions are Loss of Water Flow Bad Phase Voltage Chilled Water Freeze Protection Volts Ratio Protection Bad Leav...

Page 62: ...tarted Stage 4 cooling will start the last compressor When the evaporator water temperature is satisfied the reverse will occur with the compressor with the most run hours being stopped in each stage...

Page 63: ...ndition When power is first applied to the control panel through the circuit breaker CB the red RESET LED will illuminate for approximately 3 seconds During this time the controller is checking the co...

Page 64: ...ied via separate disconnect if freezing ambient conditions are expected 1 Close the manual liquid line shut off valves Move the circuit 1 and 2 switches to the Pumpdown and Stop position Each operatin...

Page 65: ...hown on the top line and the current MENU ITEM is shown on the bottom line of the display Either Inch Pound I P or S I units can be displayed by installing the appropriate software I P Units Temperatu...

Page 66: ...Prev Pressing PREV shifts the display to the previous menu Note When Menu I is currently in the display the first menu in the menu tree structure pressing PREV causes an end of menus message to appear...

Page 67: ...key four times This changes the menu item entry to 42 F 6 Press the ACTION group ENTER key one time This stores the new entry into the MicroTech controller memory 7 Pressing the CATEGORY group STATUS...

Page 68: ...eration of the unit Negligent or improper adjustment of these controls can result in damage to the unit or personal injury Menu 13 Control Mode One of several automatic and manual operating modes can...

Page 69: ...gh our MicroTech Open Protocol Monitor Software The Network reset option allows a signal to be sent reflecting 0 100 reset of the Lvg Evap set point chillers or Lvg Cond set point THRs based on the Ma...

Page 70: ...ithin this menu The Minimum Lift Pressure is the minimum differential pressure to be maintained across the expansion valve The dead band defines the pressure differential range within which no fan sta...

Page 71: ...r will be started The Low Pressure cut out set point determines the point at which the compressors will shut off during a pumpdown sequence The Refrigerant Freeze and Water Freeze alarm set points can...

Page 72: ...Ready PumpingDown OpenSolenoid Capacity Starting LowAmbStart 1 Table 24 MENU 4 Water Temp s Screen Display Lvg Evap xxx x F C Short F C 1 Open F C Ent Evap xxx x F C Short F C 2 Open F C D T Evap Sho...

Page 73: ...xx F C 1 N A F C SuctLine xxx x F C Open F C 2 Short Super Ht xxx x F C 3 N A F C Satur Cond xxx F C 4 N A F C Liquid Ln xxx x F C 5 N A F C SubCoolg xxx x F C 6 N A F C 7 CondD T F C Table 29 MENU 9...

Page 74: ...None 8 ResetSig xx xma Not Changeable 9 MaxChWRst xx x F C 10 0 5 5 0 0 45 0 0 0 25 0 10 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 Table...

Page 75: ...nLift 50 xxx 80 552 70 100 483 690 3 MinLift100 xxx 140 966 100 140 690 966 4 DeadBandMult x x 1 0 8 1 3 5 StageUpErr xxx 400 2760 300 990 2070 6830 6 StageDnErr xxx 100 690 50 400 340 2760 Table 39 M...

Page 76: ...n Dec 1 31 12 6 Dur 0 Day s 0 0 31 13 7 Date N A 0 N A 0 Jan Dec 1 31 14 7 Dur 0 Day s 0 0 31 15 8 Date N A 0 N A 0 Jan Dec 1 31 16 8 Dur 0 Day s 0 0 31 17 9 Date N A 0 N A 0 Jan Dec 1 31 18 9 Dur 0 D...

Page 77: ...T GZ2E01A Table 47 MENU 24 1 Curr Alarm Screen Display 1 Current Alarm 2 0 00 0 00 00 3 Evap x x psi kPa 4 Cond x x psi kPa 5 SuctLine xxx x F C 6 LiquisLn xxx x F C 7 Evap Lvg xxx x F C 8 OAT xx xx F...

Page 78: ...n cable The ADI board conditions these inputs Analog Inputs Connection The MCB receives conditioned analog inputs from the ADI board through the Analog Inputs connector via a plug in ribbon cable The...

Page 79: ...ff No power to MCB Off On Self test failure or power supply problem On Off MCB operating normally For longer than 5 seconds Table 52 Amber Status LED Indication Amber LED State Indication Off Normal o...

Page 80: ...ted via phone lines with a modem Port A can also be used to connect a licensed building automation system to the MicroTech network via Open Protocol The default communications rate is 9600 baud Port B...

Page 81: ...le levels Use the following procedure to isolate the problem Note that this procedure can require two or three spare MCB fuses Refer to the panel wiring diagram 1 Verify that circuit breaker CB1 is cl...

Page 82: ...xcessively loading the MCB s 5Vdc power supply Isolate the problem by taking resistance measurements on each of these devices with the wiring disconnected The resistance across the power input termina...

Page 83: ...C connector pull back the plug about one eighth of an inch and place the test leads against the exposed pins If there is no voltage check the wiring and the connections between the controller s 5Vdc f...

Page 84: ...MCB If the MCB appears to be functioning properly and the digital input is not being read by the MCB perform the following procedure 1 Try cycling power to the controller by opening and then closing...

Page 85: ...2 Remove power from the controller Check the ribbon cable and connections between the OB and the MCB Look for bent pins If the cable and connections are intact go to step 3 3 Remove the relay from th...

Page 86: ...unit operation Restore power by closing CB1 If the output load energizes the suspect relay is bad Replace the relay If the output load does not energize when LED is lit again check the load circuit w...

Page 87: ...an electromechanical relay If the relay is energized the relay output will be hot If the relay is de energized voltage cannot be measured at the relay output The circuit shown in Figure 33 is similar...

Page 88: ...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 condi...

Page 89: ...ally inspect unit for loose or damaged components X Inspect thermal insulation for integrity X Clean and paint as required X Electrical Check terminals for tightness tighten as necessary X Clean contr...

Page 90: ...moisture in the system During the first few months of operation the filter drier replacement can be necessary if the pressure drop across the filter drier exceeds the values listed in the paragraph a...

Page 91: ...ooling at any steady state condition Subcooling will vary somewhat with evaporator leaving water temperature and suction superheat As the evaporator superheat decreases the subcooling will drop slight...

Page 92: ...r the filter drier The subcooling values should be between 6 F 20 F 6 6 C 11 1 C The subcooling values will be highest at 75 100 load approximately 12 F 20 F 6 6 C 11 1 C and lowest at 50 load approxi...

Page 93: ...essure 4 Compressors running in reverse 4 Check for proper phasing 1 Lack of refrigerant 1 Check for leaks Repair and add charge Check liquid sightglass 2 Clogged liquid line filter drier 2 Check pres...

Page 94: ...94 AGZ 035A through 065A IOMM AGZ 3 Notes...

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Page 96: ...2510 Staunton Virginia 24402 USA 800 432 1342 www mcquay com This document contains the most current product information as of this printing For the most up to date product information please go to ww...