Dehumidifier or portable AC with dehumidify mode shows E3 and stops cooling/dehumidifying.

Safety: Unplug the unit. Do not attempt to open the sealed refrigeration system or handle refrigerant without proper certification.

Steps:

• Check airflow: Inspect the rear and side condenser grilles. Clean dust and lint from the condenser coil using a soft brush and vacuum. Ensure at least the minimum clearance from walls as specified in the manual.
• Filter cleaning: Remove and wash the air filter with mild soap and water. Let it dry completely before reinstalling.
• Ambient conditions: Ensure the unit is not operating in a very hot, confined space (e.g., small closet) that prevents heat rejection.
• Reset: After cleaning and improving airflow, leave the unit unplugged for 20–30 minutes to allow the compressor overload to cool. Plug back in and test.
• Internal checks (advanced): With power disconnected and panels removed, visually inspect the compressor wiring, overload protector, and start relay (if present) for signs of burning or loose connections. Do not bypass safety devices.
• When to call a technician: If E3 persists after cleaning and reset, there may be a refrigerant issue, a failing compressor, or a defective high-pressure switch. These require a qualified refrigeration technician to diagnose and repair.