Unit cools for a short time then shuts off, even though the room is still warm; may restart after several minutes.

Safety first: Unplug the unit before moving sensors or opening covers.

Steps:

• 1. Check sensor placement: Locate the room temperature sensor near the intake. Ensure it is not directly in the cold air stream from the outlet; reposition slightly if necessary.
• 2. Clean filter and coils: Dirty filters and coils can cause the evaporator to freeze, triggering safety shutoff. Clean as needed.
• 3. Avoid oversizing: If the unit is much larger than required for the room, it may cool too quickly and cycle frequently. Use a lower fan speed and slightly higher setpoint to reduce cycling.
• 4. Sensor replacement: If the sensor reads incorrectly (e.g., unit thinks room is much cooler than it is), replace the room thermistor.
• 5. Control board: Persistent short cycling with correct sensor readings may indicate a faulty control board, requiring replacement.