De'Longhi dehumidifier displays E5 and stops operation shortly after startup.

Safety first: Unplug the unit. Do not attempt to bypass overload protection or run the unit with covers removed.

Step-by-step:

• 1. Verify power supply: Plug the dehumidifier directly into a wall outlet (no extension cords). Ensure the outlet provides the correct voltage and is not shared with heavy loads.
• 2. Listen at startup: Turn the unit on and listen for the compressor. If it hums loudly then clicks off and E5 appears, the compressor may be locked or the start device may be failing.
• 3. Inspect for overheating: After unplugging, feel the compressor shell carefully. If it is extremely hot, allow it to cool for 30–60 minutes before further testing.
• 4. Check start relay/PTC (if accessible): Remove the side or rear panel to access the compressor terminals. The start device (relay/PTC) is a small module plugged onto the compressor pins. Inspect for burn marks or melted plastic. Replace with a compatible De'Longhi start device if damaged.
• 5. Try restart after cooling: After replacing the start device (if needed) and allowing cooling, power the unit and test. If E5 persists and the compressor does not start properly, the compressor or control board may be faulty.
• 6. Professional service: Compressor or PCB power-stage diagnosis requires electrical testing and is best handled by an authorized service center.