Samsung Air Conditioner Error Code 458

Error 458 on a Samsung air conditioner means the compressor current sensor (CT sensor) has detected a current value exceeding 20 amps for three or more consecutive minutes. This is an over-current protection fault that causes the system to shut down to prevent compressor damage. The compressor itself or its connecting wiring is the primary area to inspect.

No. Error 458 indicates a serious electrical overcurrent condition involving the compressor. Running the unit while this fault is active risks further damage to the compressor, wiring, and control boards, and there is a potential electrical safety hazard if wiring insulation is compromised. The unit should remain off until the fault is diagnosed and corrected.

Repair costs depend heavily on the root cause. If the issue is wiring damage, repairs can range from around $100 to $300 including labor. A refrigerant recharge typically falls in the $150 to $400 range. If the compressor itself has failed, replacement is significantly more expensive, often ranging from $600 to $1,500 or more depending on the unit size and labor costs in your area.

Some preliminary checks such as inspecting wiring for visible damage and verifying supply voltage can be done by a knowledgeable DIYer. However, testing compressor windings, checking for refrigerant charge, and replacing components like the compressor or CT sensor require specialized tools and, in the case of refrigerant work, EPA certification. It is strongly recommended to have a qualified technician handle this repair.

A power reset may temporarily clear the error and allow the unit to restart, but if the underlying cause, such as a failing compressor or damaged wiring, has not been corrected, the error will return within minutes once current exceeds the 20A threshold again for the required duration. A reset should only be used as part of a diagnostic process, not as a fix.