Lennox heat pump troubleshooting

Lennox R22 heat pump troubleshooting

CaseExplanation
Does not operate.• Have you made a mistake in timer operation?
• Has the fuse blown or has the circuit breaker been tripped?
• Is the power Switch at Off?
• Is the unit at the starting of Heating Operation?
If yes, Hot-start is activating.
• Is the unit in the Deicing?
If yes, wait for finishing the Deicing.
The room has a peculiar odor.• Check that this is not a damp smell exuded by the walls, carpet, furniture, or cloth items in the room.
It seems that condensation is leaking from the air conditioner.• Condensation occurs when the airflow from the air conditioner cools the warm room air.
Air conditioner does not operate for about 3 minutes when restarted.• This is the Protection device of the air conditioner.
• Wait about three minutes and operation will begin.
• If the airflow begins before its temperature become warm, it will cause an undesired cooling effect. In order to prevent this, the airflow will not begin until it is sufficiently warm.
Does not cool or heat effectively.• Is the air filter dirty? See air filter cleaning instructions.
• The room may have been very hot when the room air conditioner was first turned on. Allow time for it to cool down.
• Has the temperature been set incorrectly?
• Are the indoor unit's air inlet or outlet vents obstructed?
The air conditioner operation is noisy.• For a noise that sounds like water flowing.
-This is the sound of freon flowing inside the air conditioner unit.
• For a noise that sounds like the compressed air releasing into atmosphere.
-This is the sound of the dehumidifying water being processed inside the air conditioning unit.
Remote controller display is faint, or no display at all.• Are the batteries depleted?
• Are the batteries inserted in the opposite (+) and (-) directions?

Lennox XPG20 heat pump troubleshooting

Status LED ConditionStatus LED DescriptionStatus LED Troubleshooting Information
Green “Power” LED ONModule has power24VAC control power is present at the module terminal.
Green “Power” LED OFFModule not powering upDetermine/verify that both R and C module terminals are connected and voltage is present at both terminals.
Red “Trip” LED ONSystem and compressor check out OK. Thermostat demand signal Y1 is present, but compressor not running NOTE During 5-minute delay in defrost board, the red “trip” LED will be on.1. Verify Y terminal is connected to 24VAC at contactor coil.
2. Verify voltage at contactor coil falls below 0.5VAC when off.
3. Verify 24VAC is present across Y and C when thermostat demand signal is present; if not present, Y and C wires are reversed.
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 open if present in the system.
6. Compressor contactor has failed to close.
Red “Trip” & Yellow “Alert” LEDs FlashingSimultaneous flashing.Indicates that the control circuit voltage is too low for operation.
Yellow “Alert” Flash Code 1*Long Run Time Compressor is running extremely long run cycles1. Low refrigerant charge.
2. Evaporator blower is not running.
3. Evaporator coil is frozen.
4. Faulty metering device.
5. Condenser coil is dirty
6. Liquid line restriction (filter drier blocked if present)
7. Thermostat is malfunctioning
Yellow “Alert” Flash Code 2*System Pressure Trip or Discharge Sensor Fault - Discharge or suction pressure out of limits or compressor overloaded1. Check high head pressure or discharge line sensor.
2. Condenser coil poor air circulation (dirty, blocked, damaged).
3. Condenser fan is not running.
4. Return air duct has substantial leakage.
5. If low pressure switch is present, see Flash Code 1 information.
Yellow “Alert” Flash Code 3*Short Cycling Compressor is running only briefly1. Thermostat demand signal is intermittent.
2. Time delay relay or control board is defective.
3. If high pressure switch is present, see Flash Code 2 information.
4. If discharge sensor is present, see Flash Code 2 information.
Yellow “Alert” Flash Code 4*Locked Rotor1. Run capacitor has failed.
2. Low line voltage (contact utility if voltage at disconnect is low).
3. Excessive liquid refrigerant in the compressor.
4. Compressor bearings are seized.
Yellow “Alert” Flash Code 5*Open Circuit1. Outdoor unit power disconnect is open.
2. Unit circuit breaker or fuse(s) is open.
3. Unit contactor has failed to close.
4. High pressure switch is open and requires manual reset.
5. Open circuit in compressor supply wiring or connections.
6. Unusually long compressor protector reset time due to extreme ambient temperature.
7. Compressor windings are damaged.
Yellow “Alert” Flash Code 6*Open Start Circuit Current only in run circuit1. Run capacitor has failed.
2. Open circuit in compressor start wiring or connections.
3. Compressor start winding is damaged.
Yellow “Alert” Flash Code VOpen Run Circuit Current only in start circuit1. Open circuit in compressor start wiring or connections.
2. Compressor start winding is damaged.
Yellow “Alert” Flash Code 8*Welded Contactor Compressor always runs1. Compressor contactor failed to open.
2. Thermostat demand signal not connected to module.
Yellow “Alert” Flash Code 9*Low Voltage Control circuit <17VAC1. Control circuit transformer is overloaded.
2. Low line voltage (contact utility if voltage at disconnect is low).