Samsung Air Conditioner Error Code E164

Error code E164 on a Samsung air conditioner indicates that the evaporator inlet (EVAP IN) temperature sensor recorded no measurable change during the system's piping check sequence. During a piping check, the unit runs through a controlled operational test to verify refrigerant flow and heat exchange are functioning correctly. If the EVAP IN temperature remains static when it should be dropping or shifting, the control board interprets this as a failure in the refrigerant circuit or a component that regulates refrigerant flow into the evaporator coil.

The Electronic Expansion Valve (EEV) is the primary suspect when E164 appears. The EEV controls refrigerant flow into the evaporator, and if it fails to open or modulate properly, refrigerant will not pass through in sufficient quantity to cause a temperature change at the inlet sensor. The connection between the EEV and the PCB must be secure and intact, and the EEV coil must be fully and correctly inserted onto the valve body. A loose coil or a disconnected harness will prevent the PCB from driving the valve, resulting in no refrigerant flow and no temperature shift.

An indoor unit address mismatch is also flagged as a primary diagnostic area. In multi-zone or VRF systems, each indoor unit must have a correctly assigned address that corresponds to the master control unit (MCU). If the address is incorrect, the piping check sequence may not properly coordinate operation with the specific indoor unit, leading to a false E164 condition. Technicians should verify the address setting, confirm all EEV wiring harness connections at the PCB, and physically confirm the EEV coil is seated fully on the valve before proceeding to component-level testing.