103142-YIM-A-1204
Unitary Products Group
9
TABLE 3:
Diagnostic Label
Status LED
Status LED Description
Status LED Troubleshooting Information
Green “POWER”
Module has power
Supply voltage is present at module terminals
Red “TRIP”
Thermostat demand signal Y1 is present,
but the compressor is not running
1. Compressor protector is open
2. Outdoor unit power disconnect is open
3. Compressor circuit breaker or fuse(s) is open
4. Broken wire or connector is not making contact
5. Low pressure switch is open
6. Compressor contactor has failed open
Yellow “ALERT”
Flash Code 2
System Pressure Trip
Low pressure switch fault
1. Low refrigerant charge
2. Evaportor blower is not running
3. Evaportor coil is frozen
4. Faulty metering device
5. Condenser coil is dirty
6. Liquid line restriction (filter drier blocked if present in system)
Yellow “ALERT”
Flash Code 3
Short Cycling
Compressor is running only briefly
1. High pressure switch fault
2. Condenser coil poor air circulation (dirty, blocked, damaged)
3. Condenser fan is not running
4. Return air duct has substantial leakage
5. Thermstat demand signal is intermittent
Yellow “ALERT”
Flash Code 4
Locked Rotor
1. Run capacitor has failed
2. Low line voltage (contact utility if voltage at disconnect is low)
3. Excessive liquid refrigerant in compressor
4. Compressor bearings are seized
Yellow “ALERT”
Flash Code 5
Open Circuit
1. Outdoor unit power disconnect is open
2. Compressor circuit breaker or fuse(s) is open
3. Compressor contactor has failed open
4. Low pressure switch is open
5. Open circuit in compressor supply wiring or connections
6. Unusually long compressor protector reset time due to exteme ambient
termperature
7. Compressor windings are damaged
Yellow “ALERT”
Flash Code 6
Open Start Circuit
Current only in run circuit
1. Run capacitor has failed
2. Open circuit in compressor start wiring or connections
3. Compressor start winding is damaged
Yellow “ALERT”
Flash Code 7
Open Run Circuit
Current only in start circuit
1. Open circuit in compressor run wiring or connections
2. Compressor run winding is damaged
Yellow “ALERT”
Flash Code 8
Welded Contactor
Compressor always runs
1. Compressor contactor has failed closed
2. Thermostat demand signal not connected to module
Yellow “ALERT”
Flash Code 9
Low Voltage
Control circuit < 17 VAC
1. Control circuit transformer is overloaded
2. Low line voltage (contact utility if voltage at disconnect is low)
