Samsung Air Conditioner Error Code E557

E557 indicates a persistent electronic expansion valve (EEV) close error that has been detected for the second time. The EEV is a motorized valve inside the indoor unit that regulates refrigerant flow, and this code means the system has commanded the valve to close but the valve has failed to do so on repeated attempts. The unit flags this as a second-detection event to distinguish it from a one-time glitch.

Running the unit with E557 active is not recommended. A stuck-open EEV can allow uncontrolled refrigerant flow into the evaporator, which may cause the coil to freeze over or lead to liquid refrigerant entering the compressor, potentially causing serious compressor damage. It is best to turn the unit off until the fault is diagnosed and corrected.

Repair costs depend on the root cause. If only a loose wiring connector needs to be reseated, the cost may be limited to a service call fee, typically in the range of $75 to $150. If the EEV assembly requires replacement, parts and labor combined can range from $200 to $600 or more depending on the unit model and local labor rates. PCB replacement is generally at the higher end of that range.

The first diagnostic step, checking that the EEV wiring harness is properly connected to the indoor PCB, is something a technically confident homeowner may be able to perform after safely disconnecting power. However, if the wiring is intact, further diagnosis involves testing the EEV motor, refrigerant circuit components, and the PCB, all of which typically require a qualified HVAC technician with the proper tools and refrigerant handling certification.

A power reset may temporarily clear the error display, but because E557 is specifically a second-detection fault, the underlying problem has already persisted through at least one recovery attempt. If the wiring or component fault is not repaired, the code will return once the system restarts and attempts to operate the EEV again.