Coresense Troubleshooting; Tm Diagnostics - Nordyne S4BF-036 series Installation Instructions Manual

STATUS LED STATUS LED DESCRIPTION
Solid Green
Module has power and
"RUN" operating normally
Thermostat demand signal Y is
Solid Red
present, but the compressor is not
"TRIP"
running
Long Run Time
Yellow "ALERT" Low Refrigerant Charge
Flash Code 1 Compressor is running extremely
long run cycles
Compressor (Pressure) Trip
Yellow "ALERT" High Refrigerant Charge Discharge
Flash Code 2 pressure out of limits or compressor
overloaded
Pressure Switch Cycling
Yellow "ALERT"
Compressor is running only briefly
Flash Code 3
due to pressure switch cycling
Yellow "ALERT"
Locked Rotor
Flash Code 4
Compressor (Moderate Run)
Yellow "ALERT"
Trip
Flash Code 5

CORESENSE TROUBLESHOOTING

Supply voltage is present at module terminals
1. Compressor protector is open
• Check for high head pressure
• Check compressor supply voltage
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. High pressure switch open if present in system
6. Compressor contactor has failed open
ALERT Flash Codes
1. Low refrigerant charge
2. Evaporator blower is not running
• Check blower relay coil and contacts
• Check blower motor capacitor
• Check blower motor for failure or blockage
• Check evaporator blower wiring and connectors
• Check indoor blower control board
• Check thermostat wiring for open circuit
3. Evaporator coil is frozen
• Check for low suction pressure
• Check for excessively low thermostat setting
• Check evaporator airfl ow (coil blockages or return air fi lter)
• Check ductwork or registers for blockage
4. Faulty metering device
• Check TXV bulb installation (size, location and contact)
• Check if TXV/fi xed orifi ce is stuck closed or defective
5. Liquid line restriction (fi lter drier blocked if present in system)
6. Thermostat is malfunctioning
• Check thermostat sub-base or wiring for short circuit
• Check thermostat installation (location, level)
1. Condenser fan is not running
• Check fan capacitor
• Check fan wiring and connectors
• Check fan motor for failure or blockage
2. High head pressure
• Check high pressure switch if present in system
• Check if system is overcharged with refrigerant
• Check for non-condensable in system
3. Condenser coil poor air circulation (dirty, blocked, damaged)
4. Return air duct has substantial leakage
1. Time delay relay or control board defective
2. If high pressure switch present go to Flash Code 2 information
1. Run capacitor has failed
2. Low line voltage (contact utility if voltage at disconnect is low)
• Check wiring connections
3. Excessive liquid refrigerant in compressor
4. Compressor bearings are seized
• Measure compressor oil level
1. Evaporator blower is not running
• Check blower relay coil and contacts
• Check blower motor capacitor
• Check blower motor for failure or blockage
• Check evaporator blower wiring and connectors
• Check indoor blower control board
• Check thermostat wiring for open circuit
2. Faulty metering device
• Check TXV bulb installation (size, location and contact)
• Check if TXV/fi xed orifi ce is stuck closed or defective
3. Condenser coil poor air circulation (dirty, blocked, damaged)
4. Low refrigerant charge
Table 3. CoreSense Diagnostics & Troubleshooting
TM
STATUS LED TROUBLESHOOTING INFORMATION
15