LG Heat Pump Error Code G5

The G5 code means the suction temperature sensor has not detected a change of at least 2°C within the first 30 minutes of compressor operation. The system interprets this as the sensor having become separated from its mounting point on the suction line. The most common fix is reattaching the sensor to its correct position. If the sensor is properly mounted and the fault persists, the sensor or wiring should be further tested.

The G5 fault will generally prevent the unit from completing normal operation as a protective measure, so continued running is unlikely. You should not attempt to bypass or repeatedly reset the fault and force operation, as the control system cannot properly monitor suction conditions without an accurate sensor reading. Address the sensor issue before returning the unit to regular use.

If the repair only requires reseating a detached sensor with no replacement parts, the cost is primarily a service call fee, which typically ranges from $75 to $150 depending on your area. If the sensor itself needs to be replaced, parts and labor combined could range from $150 to $350. Refrigerant system issues discovered during diagnosis would add to the total cost.

A homeowner with some comfort around appliances can inspect the suction temperature sensor to see if it has visibly come loose from its mounting location. If the sensor is simply detached and the clip is intact, reseating it may resolve the issue. However, accessing the sensor typically requires opening the unit's panels, and if the sensor or refrigerant system needs further testing, a licensed HVAC technician should be involved.

A power reset may temporarily clear the G5 fault, but the code will return if the underlying cause is not corrected. If the suction temperature sensor is still detached or faulty after the reset, the unit will again detect the absence of temperature change during the next compressor startup cycle and trigger the fault again. The sensor issue must be physically resolved for the repair to hold.