LG Heat Pump Error Code 02

Error code 02 on an LG heat pump means the indoor unit inlet pipe temperature sensor has been detected as open or short circuit by the main control board. This sensor is a thermistor that monitors the refrigerant temperature at the inlet of the indoor heat exchanger coil. The unit will not operate normally until the fault is resolved because accurate temperature sensing is required for safe system control.

The unit will typically shut down or restrict operation when error code 02 is active, which is a protective response. Attempting to bypass this protection and run the system without a functioning inlet pipe sensor could lead to improper refrigerant temperature management and potential damage to the compressor or other components. It is best to address the fault before resuming normal operation.

A power reset may temporarily clear the error code display, but if the underlying fault with the inlet pipe sensor or its wiring still exists, the code will return once the system attempts to monitor that sensor again. A reset is useful for confirming whether a fault is persistent or intermittent, but it does not repair a damaged sensor, corroded connector, or broken wire. The root cause must be identified and corrected for the error to stay cleared.

A knowledgeable DIYer can perform the initial diagnostic steps, including checking that the sensor connector is fully seated on the PCB and measuring the sensor's resistance with a multimeter after unplugging it. If the connector is secure and the sensor reads open or short circuit, replacing the thermistor is a straightforward repair on most indoor units. However, if the PCB itself is suspected, that repair is best handled by a licensed technician.

If the fix is simply reseating a loose connector, there may be no parts cost at all, with labor being the only expense. Replacing an inlet pipe thermistor sensor typically involves a low parts cost, with the total repair bill ranging from around $75 to $250 depending on labor rates in your area. If the main PCB requires replacement, costs can rise to a range of $300 to $600 or more.