LG Air Conditioner Error Code CH41

CH41 indicates that the inverter discharge pipe thermistor has an open circuit or short circuit fault. This thermistor monitors the temperature of the refrigerant line exiting the compressor. Because the control board cannot receive valid temperature data from the sensor, the system triggers this code and limits or stops compressor operation to prevent damage.

You should not continue running the unit with CH41 active. The discharge pipe thermistor is a critical protection sensor for the compressor, and without valid temperature readings the system cannot prevent the compressor from overheating. Continued operation risks serious compressor damage, which is significantly more expensive to repair than replacing the thermistor or wiring.

A power reset may temporarily clear the code and allow the unit to restart, but if the thermistor or its wiring has genuinely failed the fault will return quickly, often within minutes of operation. Resetting without repairing the underlying problem does not fix the fault and can mask the issue while the compressor continues to run unprotected. A proper repair of the sensor or wiring is required for a lasting resolution.

Some basic checks, like inspecting the wiring harness for obvious damage or re-seating a loose connector, can be done by a knowledgeable DIYer with the unit powered off. However, properly diagnosing this fault requires measuring thermistor resistance with a multimeter and knowing the correct resistance values for that specific sensor. Replacing the thermistor or control board also requires working near refrigerant components, so professional service is recommended for most homeowners.

If the fault is a failed thermistor, parts and labor typically range from around $100 to $250 depending on the model and labor rates in your area. If the wiring harness needs repair, costs are similar or slightly lower. A control board replacement, if required, can range from $250 to $600 or more including labor. Getting a proper diagnosis first avoids replacing the wrong component.