Samsung Air Conditioner Error Code E314

Error code E314 on a Samsung air conditioner indicates a fault with the SUMP TEMP FIXED 3 sensor, which monitors temperature at a specific point in the outdoor unit's sump or refrigerant circuit. The system flags this error when the sensor reads an open or short circuit condition, but only when the outdoor ambient temperature is above -10 degrees Celsius. This threshold is important because at extremely low temperatures, sensor resistance values shift dramatically, and the control logic filters out false positives that might occur in very cold conditions. When the outdoor temp is above that threshold and the reading still falls outside the expected resistance range, the PCB determines a genuine sensor fault is present.

The SUMP TEMP FIXED 3 sensor is a thermistor-type component that changes electrical resistance in proportion to temperature. An open circuit condition means the resistance has risen to an unmeasurably high level, typically caused by a broken wire, corroded connector pin, or failed thermistor element. A short circuit condition means resistance has dropped to near zero, usually from wire insulation breakdown, moisture ingress causing a direct short, or an internally failed thermistor. Both conditions cause the PCB to receive a signal that falls outside its acceptable voltage window, triggering E314.

The first diagnostic step is to inspect the sensor connector at the PCB for physical separation, corrosion, or bent pins. After confirming the connector is fully seated, measure the sensor's resistance directly across its terminals using a multimeter. Compare that reading against the temperature-to-resistance chart for this sensor type. If resistance reads open line (infinite) or near zero, the thermistor itself has failed. If resistance is within spec, the fault may lie in the wiring harness between the sensor and the board.