Carrier GW Series Installation Instructions Manual

Contents

9S MALFUNCTION OUTPUT: Alarm output is Normally Open(NO) dry contact. If pulse is selected the alarm output will bepulsed. The fault output will depend on the dip switch setting for”ALARM”. If it is set to ”CONST”, a constant signal will beproduced to indicate a fault has occurred and the unit requiresinspection to determine the type of fault. If it is set to ”PULSE”, apulse signal is produced and a fault code is detected by a remotedevice indicating the fault. See L.E.D Fault Indication below forblink code explanation. The remote device must have amalfunction detection capability when the UPM board is set to”PULSE”.NOTE: If 24 VAC output is needed, R must be wired toALR--COM terminal; 24 VAC will be available o the ALR--OUTterminal when the unit is in the alarm condition.S LED FAULT INDICATION-- Two LED Indicators areprovided.GREEN: Power LED indicates 118--30 VAC present at the board.RED: Fault indicator wit blink codes as follows:— One Blink ---- High pressure lockout— Two Blinks ---- Low pressure lockout— Three Blinks ---- Freeze sensor lockout— Four Blinks ---- Condensate overflow— Five Blinks ---- BrownoutS DISPLAY OUTPUT: The Display output is a pulse outputconnected to the Unit Diagnostic Display (UDD) and it pulses24VAC when the unit is in an lockout alarm condition.S TEST DIP SWITCH: A test dip switch is provided to reduce alltime delays settings to 10 seconds during troubleshooting orverification of unit operation.CAUTION!UNIT DAMAGE AND/OR OPERATION HAZARDFailure to follow this caution may result in unit damageand/or improper equipment operation.Operation of unit in test mode can lead to accelerated wearand premature failure of components. The ”TEST” switchmust be set back to ”NO” after troubleshooting/ servicing.S FREEZE SENSOR: The default setting for the freeze limit trip is26_F (sensor number 1); however this can be changed to 15_F bycutting the R30 resistor located on top of the DIP switch SW1.Since freeze sensor 2 is dedicated to monitor the evaporator coil, itis recommended to leave the factory default setting on the board.The UPM controller will constantly monitor the refrigeranttemperature with the sensor mounted close to the condensingwater coil between the thermal expansion valve and water coil. Iftemperature drops below or remains at the freeze limit trip for 30seconds, the controller will shut the compressor down and enterinto a soft lockout condition. Both the status LED and the Alarmcontact will be active.The LED will flash the code associated with this alarm conditionthree (3) times. If this alarm occurs 2 times (or 4 if Dip switch is setto 4) within an hour, the UPM controller will enter into a hardlockout condition. It will constantly monitor the refrigeranttemperature with the sensor mounted close to the evaporatorbetween the thermal expansion valve and evaporator coil asshown in Fig. 6.If temperature drops below or remains at the freeze limit trip for30 seconds, the controller will shut the compressor down andenter into a soft lockout condition. Both the status LED and thealarm contact will be active. The LED will flash the codeassociated with this alarm condition six (6) times. If this alarmoccurs 2 times (or 4 if Dip switch is set to 4) within an hour, thecontroller will enter into a hard lockout condition.CAUTION!UNIT DAMAGE AND/OR OPERATION HAZARDFailure to follow this caution may result in unit damageand/or improper equipment operation.Freeze sensor will not guard against the loss of water. Aflow switch is recommended to prevent the unit fromrunning if water flow is lost or reduced.S INTELLIGENT RESET: If a fault condition is initiated, the 5minute delay on break time period is initiated and the unit willrestart after these delays expire. During this period the fault LEDwill indicate the cause of the fault. If the fault condition still existsor occurs 2 or 4 times (depending on 2 or 4 setting for Lockout dipswitch) before 60 minutes, the unit will go into a hard lockout andrequires a manual lockout reset.A single condensate overflow fault will cause the unit to go into ahard lockout immediately, and will require a manual lockout reset.S LOCKOUT RESET: A hard lockout can be reset by turning theunit thermostat off and then back on when the “RESET” dipswitch is set to “Y” or by shutting off unit power at the circuitbreaker when the “RESET” dip switch is set to “R”.NOTES: The blower motor will remain active during a lockoutcondition.SEQUENCE OF OPERATIONCooling ModeEnergizing the “O” terminal energizes the unit reversing valve thusplacing the unit into cooling mode. The fan motor starts when the“G” terminal is energized.When the thermostat calls for cooling (Y), the loop pump orsolenoid valve, if present, is energized and compressor will start.Once the thermostat is satisfied, the compressor shuts downaccordingly and the fan ramps down to either FAN ONLY mode orOFF over a span of 30 seconds (ECM Motors).NOTE: A fault condition initiating a lockout will de--energize thecompressor.Heating ModeHeating operates in the same manner as cooling, but with thereversing valve de--energized. The compressor will run until thedesired setpoint temperature on the thermostat is achieved.Once the thermostat is satisfied, the compressor shuts down and thefan ramps down in either FAN ONLY mode or turns off over aspan of 30 seconds.