Dehumidifier shows E3 and compressor will not start or runs briefly then stops.

Safety first: Unplug the unit before removing covers. Avoid touching the PCB with wet hands.

• Try a control reset: Unplug for 5–10 minutes, then plug back in and test. If E3 reappears, continue.
• Locate the humidity sensor: On many Haier dehumidifiers, the humidity sensor is mounted behind the front grille near the air intake or on a small bracket in the airflow path, connected to the PCB by a small harness.
• Inspect the sensor: Remove the front grille. Look for a small plastic sensor housing with vents. Check for dust buildup, corrosion, or physical damage.
• Clean the sensor area: Use compressed air or a soft brush to gently remove dust from the sensor vents. Do not spray liquids directly on the sensor.
• Check wiring and connectors: Follow the harness to the main PCB. Unplug and re-seat the connector. Inspect for bent pins or green/white corrosion.
• Replace the sensor: If E3 persists and the sensor appears damaged or tests out of spec (per service manual), replace the humidity sensor assembly. If a new sensor does not clear the error, the main control board may be defective and should be replaced by a technician.