LG Heat Pump Error Code CH24

CH24 means the unit's high pressure switch or low pressure switch has been activated, indicating the refrigerant circuit is operating outside of safe pressure limits. The control board shuts the system down to protect the compressor from damage. The fault can originate on either the high side or the low side of the refrigerant circuit, so pressure measurements are needed to determine which switch tripped. Common causes include refrigerant leaks, a closed service valve, or blocked airflow.

No, CH24 should not be ignored. The pressure switches are safety devices designed to prevent compressor failure, and continued operation with abnormal refrigerant pressures can cause permanent damage to the compressor. The unit should remain off until the fault is diagnosed and the underlying pressure issue is resolved.

Repair costs vary widely depending on the root cause. A service call to inspect the connector and service valves may range from $75 to $150. If a refrigerant leak is found, the cost to locate the leak, make repairs, and recharge the system can range from $250 to $600 or more depending on the refrigerant type and amount needed. Compressor replacement, if damage has already occurred, is significantly more expensive.

Some causes of CH24, such as a loose CN_PRESS connector or a partially closed service valve, can be addressed without specialized tools. However, diagnosing refrigerant pressure requires a manifold gauge set, and any refrigerant handling or recharge work must be performed by an EPA-certified technician. Attempting to add refrigerant without finding and repairing a leak will only result in the fault recurring.

Resetting the unit may temporarily clear the CH24 code and allow the system to restart, but the fault will return if the underlying pressure problem has not been corrected. A reset is useful for confirming whether the fault was caused by a transient condition, but it is not a repair. If the code returns after a reset, a full pressure and refrigerant circuit inspection is required.