Samsung Air Conditioner Error Code sx

The sx error code on a Samsung air conditioner means that both the EVAP IN and EVAP OUT temperature sensors on a specific indoor unit (identified by the number in place of "x") have simultaneously become detached from their mounting positions on the evaporator coil. The system cannot monitor evaporator temperatures without these sensors in place, so it shuts down that unit and displays the fault. The fix typically involves physically reattaching both sensors to the correct locations on the refrigerant tubing.

Operating the affected indoor unit while the sx error is active is not recommended. Without valid readings from both evaporator sensors, the system cannot properly regulate refrigerant flow or detect conditions like freezing or overheating on that evaporator coil. Continued operation could lead to coil freeze-up or compressor damage. Other indoor units in the system may continue to operate normally while the fault is isolated to the affected unit.

If the sensors only need to be reattached with no parts required, a service call may range from roughly $75 to $150 depending on your location and the technician's rates. If one or both sensors are physically damaged and need replacement, parts costs could add another $20 to $80 per sensor on top of the labor. Multi-unit or commercial systems where accessing the specific indoor unit is more involved may carry higher labor costs.

If you are comfortable opening the indoor unit's front panel and accessing the evaporator coil area, you may be able to locate and reattach the loose sensors yourself without specialized tools. However, if the sensor leads are damaged or the clips are broken, replacement parts will be needed. For multi-unit or ducted systems, it is generally recommended to have a qualified technician perform the repair to ensure both sensors are mounted to the correct points on the inlet and outlet lines.

A simple power reset will not permanently clear the sx error if the sensors remain physically detached. The control board will detect the missing sensor inputs as soon as it powers up and display the fault again. The error will only clear once both sensors are properly reattached to the evaporator coil and the system confirms it is receiving valid temperature data from both thermistors.