Dehumidifier shows E3 and stops dehumidifying; compressor does not start

Safety: Unplug the unit before opening the control panel or front housing.

Steps:

• Locate humidity sensor: On many Sencor dehumidifiers, the humidity sensor is mounted behind the front grille or integrated into the front control panel area, often in a small plastic housing with vents.
• Visual inspection: Check for dust buildup, moisture damage, or corrosion on the sensor and its connector. Clean gently with a dry, soft brush or compressed air.
• Check wiring: Ensure the sensor harness is not pinched or broken where it passes through the cabinet. Reseat the connector on both the sensor and the main PCB.
• Functional test: If you have access to a replacement sensor, temporarily connect it without mounting to see if E3 clears on power-up. If the error disappears, the original sensor is defective.
• Replace sensor: Install the correct Sencor humidity sensor module for your model, routing the cable as originally installed to avoid fan blades and sharp edges.
• PCB diagnosis: If E3 persists with a known-good sensor, the main control PCB is likely faulty and should be replaced.

Tip: Avoid spraying cleaners directly into the sensor vents; moisture can damage the RH sensor element.