LG Heat Pump Error Code 01

Error code 01 on an LG heat pump indicates that the indoor unit room temperature sensor has been detected as either open circuit or short circuit. This means the PCB cannot receive a valid temperature reading from the sensor. The system will not operate normally until the sensor fault is resolved.

The heat pump will typically shut itself down when error code 01 is active, preventing normal operation. Attempting to force the unit to run without a valid room temperature sensor reading could lead to improper heating or cooling cycles. It is best to leave the unit off and diagnose the fault before resuming use.

Resetting the unit by powering it off at the breaker for a few minutes may temporarily clear the error code display, but the fault will return immediately if the sensor or wiring problem has not been corrected. A reset is useful for confirming whether the issue is intermittent, such as a loose connector, but it is not a fix for a failed sensor or damaged wiring.

A knowledgeable DIYer can begin by checking that the sensor connector is firmly seated on the indoor PCB and inspecting the wire harness for visible damage. If the connector is secure, use a multimeter to measure the sensor's resistance after unplugging it and compare the result to expected values for the room temperature. If the sensor has failed or wiring is damaged, replacing the thermistor is a straightforward repair, but working on PCB components or refrigerant-related parts should be left to a licensed technician.

If only the room temperature thermistor needs replacement, parts typically cost in the range of $10 to $40 depending on the specific model. With professional labor, the total repair cost generally falls between $75 and $200. If the indoor PCB is at fault, the cost can rise significantly, often ranging from $200 to $500 or more including parts and labor.