Samsung Air Conditioner Error Code YEL_ON_RED_ON

YEL_ON_RED_ON indicates a heatsink sensor error in the inverter drive system. The controller has detected an abnormal or missing signal from the temperature sensor located on the IPM module heatsink. The unit shuts down to prevent potential thermal or electrical damage until the fault is resolved.

No, you should not continue operating the unit while this error is active. The heatsink sensor is a protective component, and bypassing or ignoring this fault could allow the IPM module to overheat without any thermal protection. This risks permanent damage to the inverter board and compressor, and in severe cases could create a fire or electrical hazard.

A power reset may temporarily clear the error code and allow the unit to restart, but if the underlying fault, such as a cracked solder joint, failed sensor, or blocked airflow, is still present, the code will return. Resetting without diagnosing and correcting the cause is not a permanent fix and can allow the problem to worsen over time.

Some causes, such as restricted airflow or a dirty heatsink, can be addressed without specialized tools. However, diagnosing and repairing solder joint cracks at IPM module pins 24 and 25 requires electronics experience, soldering equipment, and comfort working with inverter-driven power circuits. Most homeowners should have a qualified technician handle this repair due to the high-voltage components involved.

Repair costs depend on the root cause. If the issue is a cracked solder joint that can be reflowed, labor costs may range from $75 to $200. If the IPM module or heatsink sensor requires replacement, parts and labor combined could range from $200 to $600 or more depending on the specific unit and local service rates.