Unit displays E2 and may run the fan but not cool properly; sometimes cycles off prematurely.

Safety: Disconnect power before opening the cabinet. Edges around the coil and chassis are sharp; wear cut-resistant gloves.

Steps to address E2:

• Remove front cover: Take off the front grille and filter. On portable and window Arctic King units, remove any additional screws to access the evaporator coil area.
• Locate the evaporator sensor: This thermistor is usually clipped directly to the evaporator coil tubing or fins near the center or side of the coil.
• Check mounting: Ensure the sensor is firmly clipped to the coil and not hanging loose. A loose sensor can misread temperature and trigger E2.
• Inspect wiring: Follow the sensor wires back to the control board. Look for pinched, cut, or corroded wires. Reseat the connector on the PCB.
• Test resistance: With the unit unplugged, disconnect the sensor and measure resistance. Compare to the room sensor if they are the same part number; they should be in a similar range at the same temperature. Infinite or zero resistance indicates failure.
• Replace sensor: If readings are out of spec or the sensor is damaged, install a new Arctic King evaporator temperature sensor. Clip it securely to the coil in the same location as the original.
• Check for icing issues: If the sensor is good but E2 persists, inspect the coil for heavy ice buildup (which can be caused by low airflow or low refrigerant). Clean the filter and coil. Persistent icing may require a technician to check refrigerant charge and system pressures.