Samsung Air Conditioner Error Code E168

Error code E168 on a Samsung air conditioner indicates that both the inlet and outlet heat exchanger temperature sensors on the indoor unit have been detected as disconnected or open-circuit simultaneously. These two thermistor sensors monitor the refrigerant temperature as it enters and exits the indoor evaporator coil, allowing the control board to regulate capacity, detect freeze conditions, and protect the system from operating outside safe thermal parameters. When both sensors are flagged at the same time, the unit cannot accurately track heat exchange performance and shuts down to prevent damage.

The most common cause of this fault is physical disconnection of both sensor connectors from the indoor control board, which can happen due to vibration over time or during a prior service visit where connectors were not fully reseated. Each sensor is a negative temperature coefficient (NTC) thermistor that changes resistance predictably with temperature. If the board reads an open circuit or a resistance value far outside the expected range for ambient conditions, it interprets the sensor as detached and triggers E168.

Because both sensors are reported as detached simultaneously, technicians should first inspect the harness connectors at the control board before testing the sensors themselves. A wiring harness fault, such as a broken wire or corroded connector, could cause both sensors to appear open even if the thermistors are physically intact. If connectors and wiring check out, each thermistor should be tested individually for proper resistance at a known temperature to confirm whether one or both sensors require replacement.