Daikin McQuay WGZ030DW Operating And Maintenance Manual
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Daikin McQuay WGZ030DW Operating And Maintenance Manual

Water-cooled scroll compressor chillers
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Operating and Maintenance Manual
Water-Cooled Scroll Compressor Chillers
WGZ030DW to WGZ200DW, Packaged Water-Cooled Chiller
WGZ030DA to WGZ200DA, Chiller with Remote Condenser
30 to 200 Tons, 105 to 700 kW
R-410a
50-60 Hertz
Software Version WGZDU0102F
OMM 1130
Group: Chiller
Part Number: OMM 1130
Effective: March 2012
Supercedes: November 2011

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Summary of Contents for Daikin McQuay WGZ030DW

  • Page 1 Group: Chiller Part Number: OMM 1130 Effective: March 2012 Supercedes: November 2011 Water-Cooled Scroll Compressor Chillers WGZ030DW to WGZ200DW, Packaged Water-Cooled Chiller WGZ030DA to WGZ200DA, Chiller with Remote Condenser 30 to 200 Tons, 105 to 700 kW R-410a 50-60 Hertz...

  • Page 2: Table Of Contents

    Table of Contents EXV Control ........51 Introduction ........3 Using the Controller......52 General Description ......3 Nomenclature ........3 Menu Screens........53 Water Pressure Drop ......3 Menu Descriptions ......54 Components .......... 6 BAS Interface ........73 Unit Configuration ......7 Parameter Details ........

  • Page 3: Introduction

    Introduction General Description Daikin McQuay Type WGZ water chillers are designed for indoor installations Equipment room temperature for operating and standby conditions is 40°F to 122°F (4.4°C to 50°C). They are available with water-cooled condensers (Model DW), or arranged for use with remote air-cooled or evaporative condensers (Model DA).
  • Page 4 Figure 1, Evaporator Pressure Drop, WGZ030D – WGZ200D Minimum Flow & Pr. Drop Nominal Flow & Pr. Drop Maximum Flow & Pr. Drop Curve Model Inch-Pound S.I. Inch-Pound S.I. Inch-Pound S.I. WGZ030D 56.3 90.0 18.8 150.0 16.6 49.7 WGZ035D 64.9 10.8 103.8 26.3...
  • Page 5 Figure 2, Condenser Pressure Drop, WGZ030D – WGZ200D Flow Rate (GPM) Min. Flow & PD Nom. Flow & PD Max. Flow & PD Unit Model WGZ030D 56.1 89.7 18.8 149.5 17.4 52.0 WGZ035D 64.9 10.2 103.8 25.7 173.0 23.9 10.9 71.4 WGZ040D 76.3...

  • Page 6: Components

    Components Figure 3, Compressor Locations Evaporator and Evaporator Condenser Connections Circuit 2 Circuit 1 Control Panel NOTE: Models WGZ150 to WGZ200 add a #5 compressor to circuit #1 and a #6 compressor to circuit #2. WGZ030D through WGZ200D OMM 1130...

  • Page 7: Unit Configuration

    Unit Configuration The chiller units have two refrigerant circuits, Models WGZ 030 to WGZ 130 have two tandem scroll compressors (total of four), a single two-circuited brazed plate evaporator, a single two-circuited water- cooled condenser, interconnecting refrigerant piping and a control panel with associated sensors and transducers.

  • Page 8: Field Wiring Diagrams

    Field Wiring Diagrams Figure 5, WGZ030DW – WGZ200DW Field Wiring Diagram (Packaged Unit) DISCONNECT UNIT MAIN GND LUG (BY OTHERS) TERMINAL BLOCK 3 PHASE TO COMPRESSOR(S) POWER SUPPLY FUSED CONTROL CIRCUIT TRANSFORMER 120 VAC DISCONNECT TB1-20 (BY OTHERS) FIELD SUPPLIED...
  • Page 9 Figure 6, WGZ030DA – WGZ200DA Field Wiring Diagram (Remote Condenser) UNIT MAIN DISCONNECT TERMINAL BLOCK GND LUG (BY OTHERS) 3 PHASE TO COMPRESSOR(S) POWER SUPPLY FUSED CONTROL CIRCUIT TRANSFORMER DISCONNECT TB1-20 (BY OTHERS) FIELD SUPPLIED FUSE 120VAC OPTION CONTROL POWER CONTROL (BY OTHERS) CIRCUIT...

  • Page 10: Control Panel Layout

    Control Panel Layout Table 1, Typical Control Panel, 4-Compressor Unit (3) 120V/24V Microtech Transformers Controller LineV/120V Control Transformer (2) Circuit Mechanical Hi-Pressure Control Switch Relays Transformer Fuses, Primary Control (4) Compressor Transformer Fuse, Circuit Breakers Secondary Optional (4) Compressor Disconnect Contactors Switch Location for...

  • Page 11: Start-Up And Shutdown

    11. Make sure all wiring and fuses are of the proper size. Also make sure that all interlock wiring is completed per Daikin McQuay diagrams. 12. Verify that all mechanical and electrical inspections by code authorities have been completed.
  • Page 12 11. Set pumpdown switches PS1 and PS2 to “auto” for restart and normal operation. 12. Start the system by setting the system switch S1 to on. 13. After running the unit for a short time, check the oil level in each compressor crankcase, rotation of condenser fans (if any), and check for flashing in the refrigerant sight glass.
  • Page 13 Start-up after Extended Shutdown 1. Inspect all equipment to see that it is in satisfactory operating condition. 2. Remove all debris that has collected on the surface of the condenser coils (remote condenser models) or check the cooling tower, if present. 3.

  • Page 14: Sequence Of Operation

     If the outside air temperature higher than 75.0°F the condenser fan staging logic changes to bring on the first fan on when the condenser pressure is greater than 140 psi.  The standard condenser fan staging logic would start the first condenser fan when the condenser pressure is higher than 200.0 psi.
  • Page 15 However, in some circumstances this methodology can cause the LWT to drop to dangerously low levels, with the evaporating temperature below the freeze point, before stopping. In the example shown in Figure 7, the Shutdown Temp (last compressor off) would be 36F. This would result in a refrigerant evaporating temperature approaching freezing, so the rule is amended to read: If the Cool Leaving Water Temperature (LWT) set point is less than half the Control Band...
  • Page 16 Automatic Pumpdown WGZ units are equipped with single pumpdown control. When the last compressor running on either circuit is ready to shut off, the liquid line solenoid valve (LLSV) is closed first and the compressor continues to run until the pumpdown pressure is reached, at which time the compressor shuts off. The shut off pressure is set at 15 psi below the Low Evaporator pressure Unload setpoint.
  • Page 17 Circuit 2 Number of Fans = 4 Number of fans = 6 Number of fans = 8 Stage # Stage # Stage # Number of fans = 8 (R410A)Number of fans = 10 (R410A)Number of fans = 12 Stage # 6&8 Stage # 6&8...

  • Page 18: Microtech Ii Controller

    MicroTech II Controller Controller Software Version This manual is based on software version WGZD20102F. The “02F” is the version descriptor. The version installed in a unit can be viewed by pressing the MENU and ENTER keys simultaneously, then pressing MENU to return to the regular menu screen. General Description The MicroTech II controller’s state-of-the-art design will not only permit the chiller to run more efficiently but will also simplify troubleshooting if a system failure occurs.
  • Page 19 Keypad/Display A 4-line by 20-character/line liquid crystal display and 6-key keypad is mounted on the unit controller. Its layout is shown below. Figure 8, Keypad and Display in MENU Mode Key to Screen Pathway Menu Key Air Conditioning < ALARM <...
  • Page 20 Table 4, Analog Outputs Description Output Signal Range Cooling Tower Bypass Valve Position 0 to 10 VDC 0 to 100% Open Cooling Tower VFD Speed 0 to 10 VDC 0 to 100% Circuit #1 Electronic Expansion Valve 0 to 10 VDC 0 to 100% Circuit #2 Electronic Expansion Valve 0 to 10 VDC...

  • Page 21: Expansion I/O Controller

    Table 6, Continued Description Type Load Output OFF Output ON Motor Control Relay #3 = Compr#3 Starter Compressor OFF Compressor ON Condenser Fan #3– Water Cooled =N /Tower Fan C1 / Fan Contactor Fan OFF Fan ON #2-Water Cooled=Y (R22,R407C) Motor Control Relay #5 = Compr#5 (R134a,R410a) Starter Compressor OFF...

  • Page 22: Setpoints

    The PW (password) column indicates the password level that must be active in order to change the setpoint. Passwords are as follows: O = Operator [0100] M = Manager [2001] Table 7, Setpoints (setpoints with * are set at Daikin McQuay factory) Description Default Range Unit Enable...
  • Page 23 Table 7, Continued Description Default Range Expansion Valve Type Electronic Thermal, Electronic Circuit 1 EXV Control Auto Auto, Manual Circuit 1 EXV Position 0-100% Circuit 2 EXV Control Auto Auto, Manual Circuit 2 EXV Position 0-100% MaxOpPress 142 – 170 psig SuperheatTarg 8-12°F Alarms...

  • Page 24: Automatic Adjusted Limits

    Automatic Adjusted Limits The following are set points that will be limited based on the option selected. Evaporator Leaving Water Temperature Mode Refrigerant Type Range Unit Mode = Cool R134a,R22, R407C, R410A 40 to 60F Unit Mode = Cool w/Glycol R134a,R22, R407C 20 to 60F Unit Mode = Cool w/Glycol...

  • Page 25: Dynamic Defaults

    Dynamic Defaults Some set points will have a particular default value loaded when another setting is changed. Refrigerant Dependent Defaults Refrigerant Type Set Point R134a R407C R410A Low Evaporator Pressure Hold 29 psi 59 psi 60 psi 101 psi 28 psi Low Evaporator Pressure Unload 58 psi 59 psi...
  • Page 26 When the alarm occurs due to this trigger, it can auto reset the first two times each day, with the third occurrence being manual reset. For the auto-reset occurrences, the alarm will reset automatically when the evaporator state is Run again. This means the alarm stays active while the unit waits for flow, then it goes through the recirculation process after flow is detected.
  • Page 27 When the evaporator pressure goes below the Low Evaporator Pressure Unload set point, a timer starts. If this timer exceeds the freeze time, then a ‘Evap Press Low Cir N’ alarm trip occurs. If the evaporator pressure rises to the unload set point or higher, and the freeze time has not been exceeded, the timer will reset.
  • Page 28 Trigger: Sensor shorted or open AND TGZ unit (refrig = R134a) AND operating in ‘heat’ mode. Action Taken: Normal stop all circuits Reset: This alarm can be cleared manually via the keypad, but only if the sensor is back in range. Suction Temperature Sensor Fault Alarm description (as shown on screen): SuctT Sensor Fail N Trigger: Sensor shorted or open AND Expansion Valve Type = Electronic...

  • Page 29: Limit Events

    Action Taken: Rapid stop all circuits Reset: Auto clear when EXB1 is communicating with CP1. Alarm Log An alarm log stores the last 25 alarms and/or events to occur. When an alarm or event occurs, it is put into the first slot in the alarm log and all others are moved down one, dropping the last entry. In the alarm log, the date and time the alarm occurred are stored, as well as a list of other parameters.
  • Page 30 Reset: While still running, the event will be reset if evaporator pressure > (Low Evaporator Pressure - Hold set point + 8psi for R134a/R22/R407C or 13 psi for R410A). The event is also reset if the circuit state is no longer run. High Condenser Pressure - Unload Event description (as shown on screen): CondPressHighUnloadN Trigger:...
  • Page 31 Trigger: Sensor shorted or open. Action Taken: None. Reset: N/A Liquid Line Temperature Sensor Fail (TGZ unit only) Event description (as shown on screen): Low Source Temp Trigger: Sensor shorted or open. Action Taken: None. Reset: N/A Low Source Water Temperature (TGZ unit in ‘heat’ mode only) Event description (as shown on screen): LiqL Sensor Fail N Trigger: Unit is in heat mode and the leaving evaporator water temperature drops below the Low Source Temperature set point.

  • Page 32: Controller Operation

    Controller Operation Calculations The Control Band defines the temperatures around the Controlling Leaving Water Temperature set point where compressors will be staged on or off. In cool mode, the controlling leaving water temperature set point will be Evap LWT. In heat mode, the controlling leaving water temperature set point will be Heat LWT.
  • Page 33 Stage Up Temperature = Heat LWT - (Control Band/2) The Stage Down temperature is calculated as: Stage Down Temperature = Heat LWT + (Control Band/2) The Heat Start up and Shutdown temperatures are calculated from the Control Band. The Start Up temperature determines when the first compressor on the unit will start.
  • Page 34 1. Heating Leaving Water Temperature set point (Heat LWT) 2. Heating Maximum Reset set point (Htg MaxRes) 3. LWT Reset signal 4-20mA Reset is 0ºF and the active leaving water set point is equal to the Heat LWT set point if the reset signal is less than or equal to 4 mA.
  • Page 35 active heating leaving water set point is reset using the following parameters: 1. Heating Leaving Water Temperature set point (Heat LWT) 2. Heating Maximum Reset set point (Htg MaxRes) 3. Heating Start Reset Delta Temperature (Htg StrtResDT) 4. Condenser Delta Temperature (condenser leaving water temperature minus entering temperature) Reset is accomplished by changing the Active Heating Leaving Water set point from the Heat LWT set point to the value of [Heat LWT (-) Heating Maximum Reset set points] as the condenser delta temperature (leaving minus entering) varies from the Heating Start Reset Delta T set point towards 0ºF...
  • Page 36 Evaporator Saturated Temperature Evaporator saturated temperature is calculated from the evaporator pressure for each circuit. R410a Evaporator Saturated Temperatures When R410a refrigerant is selected the refrigerant pressure will be fitted to a curve made up of 24 straight-line segments. The accuracy of calculated saturated temperatures are less than +/- 0.5°F when compared to standard look up tables for R410a.
  • Page 37 Changing the Unit Enable Set Point is accomplished according to the following table. NOTE: An “x” indicates that the value is ignored. Unit Off Control Source Remote Key- Unit Input Set Point Input pad Entry Request Enable SWITCHES SWITCHES KEYPAD KEYPAD NETWORK NETWORK...
  • Page 38 Power Up Start Delay After powering up the unit, the motor protector modules may not reset for up to 150 seconds. After the control is powered up, no compressor can start for 150 seconds. Motor protect inputs are ignored during this time so as to avoid tripping a false alarm.
  • Page 39 Unit State Diagram Power On Pumpdown Auto Evaporator Water Pump State Control (Evap State) The state-transition diagram shown below controls operation of the evaporator pump. Evaporator Pump State Diagram Unit State = Off AND Unit State=Auto OR No Evap Water Freeze Alarm Evap Water Freeze Alarm Unit State = Off AND No Evap Water Freeze Alarm...
  • Page 40 Primary/Standby Pump Staging The pump designated as primary will start first. If the evaporator state is start for a time greater than the recirculate timeout set point and there is no flow, then the primary pump will shut off and the standby pump will start.
  • Page 41 8-Fan Remote Condenser, R22, R407C Stage Fans Operating on Circuit 1 Fans Operating on Circuit 2 Fan 1 Fan 2 Fans 1, 3 Fans 2, 4 Fans 1, 3, 5 Fans 2, 6, 8 Fans 1, 3, 5, 7 Fans 2, 4, 6, 8 8-Fan Remote Condenser, R410A Stage Fans Operating on Circuit 1...
  • Page 42 The Stage Down Error Step is added to Stage Down Accumulator once every Stage Down Error Delay seconds. When the Stage Down Accumulator is greater than the Stage Down Error Set Point another stage of condenser fans turn off. The last stage on will not shut off until the circuit is in an off state. When stage down occurs or the saturated temperature rises back within the Stage Down dead band the Stage Down Error Accumulator is reset to zero.
  • Page 43 Pump Selection The pump output used will be determined by the Cond Pump Control set point. The setting allows the following configurations: #1 only – Pump 1 will always be used. #2 only – Pump 2 will always be used. Auto –...
  • Page 44 When the condenser pump starts, the stage up timer shall start. The first stage shall turn ON when the following conditions are met: The stage up timer completes The ECWT is > Stage #1 ON set point Bypass valve position is > the Stage Up @ set point (only if Valve/VFD Control set point = Valve Stage) Additional stages can turn on (up to the number specified by the Tower Stages set point) when above conditions are met for the next stage plus the following condition:...
  • Page 45 always limited between the Valve Control Range (Min) set point and the Valve Control Range (Max) set point. A valve increment shall be computed once every 5 seconds according to the following equation. Increment = [(Error) * (Error Gain set point)] + [(Slope) * (Slope Gain set point)] Where: Error = ECWT –...
  • Page 46 If Unit Mode = Heat AND At least one compressor is running AND LWT error > 0.5 * Control band AND Pulldown rate <= Max pulldown rate AND Compressors running < unit capacity limit AND Stage up timer expired THEN Stage Up Now = True Stage Down Now The Stage Down Now flag is set based on the following tests:...
  • Page 47 Low Ambient Start (WaterCooled = NO) In order to avoid low evaporator pressure alarms at startup, low OAT start logic allows for running at low evaporator pressures for a longer time than normal as well allowing multiple compressor restart attempts before locking out the circuit.
  • Page 48 10 seconds later if the pressure is still above the unload set point. On that circuit’s VIEW CIRCUITn (1) screen is displayed the “Hold Clear @” value which is the limit by which the condenser pressure must drop to allow for additional loading. A High Condenser Pressure Unload event will be recorded in the Event Log.
  • Page 49 Limit Signal vs. Max Stage Limit Signal vs. Max Stage (with 4 compressors) (with 6 compressors) Stage Stage 12.0 16.0 20.0 12.0 14.7 17.3 20.0 Limit Signal (mA) Limit Signal (mA) 25.0 50.0 75.0 100.0 16.7 33.3 50.0 66.7 83.4 100.0 Limit Signal (%) Limit Signal (%)
  • Page 50 triggered, the evaporator water pump will remain off and no compressors will start until the OAT rises to the lockout set point plus 5F. Manual Compressor Control The operator can manually enable and disable individual compressors. When a compressor has been disabled it is considered unavailable to start in the staging logic.

  • Page 51: Exv Control

    EXV Control The EXV control logic is active regardless of the expansion valve type setting. While a circuit is in the run state, the EXV controls suction superheat. The superheat target is 8 F. PID logic will be used to control the superheat to the target value.

  • Page 52: Using The Controller

    Using the Controller Getting Started There are two basic procedures to learn in order to utilize the MicroTech II controller:  Navigating through the menu matrix to reach a desired menu screen and knowing where a particular screen is located. ...

  • Page 53: Menu Screens

    time) by using the four ARROW keys. A typical menu screen is shown in the following figure. Pressing the MENU key from any menu screen will automatically return you to the MENU mode. Figure 9, Display in the Shortcut (SCROLL) Mode and Keypad Layout MENU Key Air Conditioning VIEW UNIT STATUS...

  • Page 54: Menu Descriptions

    The menus are arranged in a matrix of screens across a top horizontal row. Some of these top-level screens have sub-screens located under them. The content of each screen and its location in the matrix are shown in Figure 10. A description of each menu begins on page 54. The arrow keys on the controller are used to navigate through the menus.
  • Page 55 ALARM menu: ALARM < ACTIVE < < < VIEW menu: VIEW < COMPRESSOR < UNIT < EVAPORATOR < FANS/TOWER VIEW UNIT menu: VIEW < TEMP UNIT < STATUS < REFRIGERANT SET menu: SET < ALARM LIMITS < UNIT SPs < COMPRESSOR SPs <...
  • Page 56 This menu gives the status of digital outputs (D.O.), 1=ON, 0=OFF. Numbers are 1 through 18. See Table 6 on page 20 for number reference. VIEW UNIT STATUS (5) D.I. 111111111 123456789012345678 000000000000000000 This menu gives the status of digital inputs (D.I.), 1=ON, 0=OFF. Numbers are 1 through 18. See Table 5 on page 20 for number reference.
  • Page 57 WGZ unit TGZ Unit (R134a) VIEW UNIT TEMP VIEW UNIT TEMP LWT Pulldn= XX.X F LWT Pulldn= XX.X F Control Band= XX.XF Control Band= XX.XF VIEW UNIT TEMP Control Temps Start Up XX.XF Stage Up XX.XF VIEW UNIT TEMP Control Temps Stage Down XX.XF Shut Down...
  • Page 58 VIEW CIRCUIT 2 VIEW CIRCUIT#2 Comp 2 = OFF Hours = XXXXX Starts = XXXXX VIEW CIRCUIT#2 Comp 4 = OFF Hours = XXXXX Starts = XXXXX If # of Compresors = 6 Only for R410A or R134a VIEW CIRCUIT 1 Comp6=Off Hours = XXXXX...
  • Page 59 Units with EEV only VIEW REFRG Cir 1 (5) EXV Ctrl = XXX EXV Pos = XXX.X% SH Target = XX.XF TGZ Units Only (R134a) VIEW REFRG Cir 1 (6) EXV Ctrl Range XX.X% ---XX.X% VIEW REFRG Cir 2 (1) Evap Press XXX.X psi Cond Press XXX.X psi R 134a, R22, R410A...
  • Page 60 Water Cooled = Y Only or TGZ Unit (R134a) VIEW TOWER (1) Stages ON = 1 of 2 EntCondTemp = XXX F Setpoint = XXX F The first Stages ON value is the number of fan stages ON. The second number is the Tower Stages setpoint (0 if Tower Control = None).
  • Page 61 Either type alarm will light a red light in back of the LEFT-ARROW KEY. The light will go out when the fault is cleared. To clear the fault, scroll down to the last screen and press ENTER. If other faults have appeared, they will all be cleared at the same time.
  • Page 62 SET UNIT SPs Available Modes =COOL Set w/Unit Switch Off SET UNIT SPs Evap LWT = XX.XF Ice LWT = XX.XF EvapDeltaT= XX.XF SET UNIT SPs Start Delta= XX.XF Stop Delta= XX.XF Demand Limit = ON See page 14 for an explanation of compressor staging. WGZ Units Only TGZ Units Only (R134a) SET UNIT SPs...
  • Page 63 SET UNIT SPs CLOCK dd/mmm/yyyy hh:mm:ss SET UNIT SPs (9) SET UNIT SPs (9) SET UNIT SPs Units = F/psi Units = F/psi Units = F/psi Lang = ENGLISH Lang = ENGLISH Lang = ENGLISH Refrig = None Refrig = R22 Refrig = R407C SET UNIT SPs (9) SET UNIT SPs...
  • Page 64 SET UNIT SPs (15) Suction Temp Sensor Cir1 Offset 00.0 °F Cir2 Offset 00.0 °F WGZ Unit (R22,R407C,R410A) TGZ Unit (Refrig = 134a) SET UNIT SPs (16) SET UNIT SPs (16) Clg ResType = X Liq Line Temp Sensors Clg MaxRes = XX.X ºF Circ1 Offset = 00.0 ºF Circ2 Offset = 00.0 ºF WGZ Unit (R22,R407C,R410A)
  • Page 65 This menu sets the anti-recycle timers. Stop-Start is the time required before starting a compressor after it has stopped. Start-Start is the time required before starting a compressor after the last time it has started. It is recommended that the default values of 5 minutes and 15 minutes not be changed. SET COMP SPs InterStgUp =XXXsec...
  • Page 66 SET ALARM LIMITS SET ALARM LMTS Low EVAP Pressure Hold=XXXpsi Unload=XXXpsi The Hold and Unload have the same default value of 59 psi. If two compressors are running, the LowEvPrUnld is in effect and the lag compressor will be shut off to unload the unit. If one compressor is running, the LowEvPrHold is in effect and the lag compressor is prevented from starting, thereby holding the unit capacity.
  • Page 67 WaterCooled=ON SET ALARM LIMITS (5) Cond Freeze= XX.X °F CondFlowProof= XX sec TGZ in Heat Mode SET ALARM LIMITS (6) LowSourceTmp = XX.XF LowSourceDif = XX.XF Set Air-Cooled Condenser Fans Water-cooled = Off SET FANS SPs Fan Stages=X Speedtrol=Yes/No Water-cooled = Off SET FANS SPs Stage ON Deadband (F) Stg2...
  • Page 68 Set Cooling Tower Control The MicroTech II controller is capable of controlling cooling tower water temperature on chillers using water-cooled condensers. Output wiring connection points are shown on the field wiring diagrams. [Water Cooled = Y] - Condenser Pump on with first Compressor on. Tower fan control is active when the Tower Control setpoint is set to Temperature and the condenser pump is in the RUN state.
  • Page 69 Stage ON Temp is the entering condenser water temperature (ECWT) that will turn on tower fan #1 and #2. Default settings are 70F and 75F. Cold condenser water will improve unit efficiency but too cold can cause erratic operation. Settings below 60F are not recommended. Water-cooled On SET TOWER SPs (3) StageDiff = XX.XF...
  • Page 70 Stage Mode (above) except that (1) it shall be kept at zero until the first fan stage is ON, and (2) the following setpoints do not apply. Valve Control Range (Min) Valve Control Range (Max) Valve Type Valve Type settings are NC (normally closed to tower) or NO (normally open). These settings establish the operation of a tower bypass valve (must be a 3-way valve).
  • Page 71 Water-cooled = Y SET TOWER SPs (6) ValveStartPosition Min = XXX% @XXXF Max = XXX% @XXXF The ValveStartposition is the position of the valve when the unit starts. Default for minimum start position is 0%, and 100% for maximum position. Water-cooled = Y SET TOWER SPs (7) Valve Control Range...
  • Page 72 Water Cooled = ON Water Cooled = OFF TEST UNIT TEST UNIT Twr Bypass= XXX.X % Fan 2=OFF Fan 4=OFF Twr VFD= XXX.X % Fan 6/8=OFF Fan 10=OFF TEST UNIT EXV Cir 1= XXX.X % EXV Cir 2= XXX.X % Editing Review Editing shall be accomplished by pressing the ENTER key until the desired field is selected.

  • Page 73: Bas Interface

    BAS Interface The BAS interface will use the supervisor port on the controller as a connection point. Protocols Supported The following building automation system (BAS) protocols are supported. It is possible to change the building automation interface without loading different software. BACnet®...

  • Page 74: Parameter Details

    Table continued Type Index Description LONworks BACnet Modbus Active alarms 11 Active alarms 12 Active alarms 13 Active alarms 14 Active alarms 15 Active alarms 16 Network chiller mode set point LON Chiller run mode Active chiller mode Network demand limit default set point Network chiller mode default set point Sequence Status Bit 1 –...
  • Page 75 Chiller Mode Applies to Integer 17 and Integer 19. Network Chiller Mode Set Point and Active Chiller Mode use the same numbering scheme to represent ice mode or cool mode. The output representing the mode is shown below for each protocol. Mode LONworks BACnet...
  • Page 76 enabled set point is set to disable. A ten second timer should lapse, then the “ignore network defaults” setting is checked. If this is set low, then the defaults for BAS cool set point, network limit, unit enable, and unit mode will be loaded. If the setting is set high, then no defaults are loaded and the status of the BAS enable set point is restored to the original value.

  • Page 77: Optional Controls

    Optional Controls Phase/Voltage Monitor (Optional) The phase/voltage monitor is a device that provides protection against three-phase electrical motor loss due to power failure conditions, phase loss, and phase reversal. Whenever any of these conditions occur, an input relay is deactivated, disconnecting power to the thermostatic control circuit. The compressor does a rapid shutdown including a pump down cycle.

  • Page 78: System Maintenance

    System Maintenance General To provide smooth operation at peak capacity and to avoid damage to package components, a program of periodic inspections should be set up and followed. The following items are intended as a guide to be used during inspection and must be combined with sound refrigeration and electrical practices to provide trouble-free performance.

  • Page 79: Sightglass And Moisture Indicator

    All tandem and triple compressors on WGZ units come equipped with oil equalization lines connecting the crankcase of each set of compressors in each refrigerant circuit. This allows the oil to move from one compressor crankcase to the other during normal operation, and balance between the two when the compressors are off.

  • Page 80: Maintenance Schedule

    Maintenance Schedule I. Compressor A. Performance Evaluation (Log & Analysis) * B. Motor  Meg. Windings  Ampere Balance (within 10%)  Terminal Check (tight connections, porcelain clean)  Motor Cooling (check temperature) C. Lubrication System  Oil Level  Oil Appearance (clear color, quantity) ...

  • Page 81: System Service

    System Service DANGER Service on this equipment is to be performed only by qualified refrigeration personnel. Causes for repeated tripping of equipment protection controls must be investigated and corrected. Disconnect all power before doing any service inside the unit or serious personal injury or death can occur.
  • Page 82 If the problem can be traced to the power element only, it can be unscrewed from the valve body without removing the valve, but only after pumping the unit down. Table 8, Thermostatic Expansion Valve CAUTION Adjustment of expansion valve should only be performed by a qualified service technician.

  • Page 83: Troubleshooting Chart

    Troubleshooting Chart PROBLEM POSSIBLE CAUSES POSSIBLE CORRECTIVE STEPS Main switch, circuit breakers open. Close switch Fuse blown. Check electrical circuits and motor winding for shorts or grounds. Investigate for possible overloading. Replace fuse or reset breakers after fault is corrected. Thermal overloads tripped or fuses Overloads are auto reset.

  • Page 84: Warranty Statement

    Low water flow. Adjust flow. Opens Low suction pressure. See “Low Suction Pressure.” Warranty Statement Limited Warranty Consult your local Daikin McQuay Representative for warranty details. Refer to Form 933-43285Y. To find your local Daikin McQuay Representative, go to www.daikinmcquay.com. OM WGZC-1...
  • Page 86 Now that you have made an investment in modern, efficient Daikin McQuay equipment, its care should be a high priority. For training information on all Daikin McQuay HVAC products, please visit us at www.daikinmcquay.com and click on training, or call 540-248-9646 and ask for the Training Department.

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