Dehumidifier shows E9 and shuts down; may occur after power fluctuations or storms.

Safety first: Unplug the unit before opening any panels. Static discharge can damage electronics; ground yourself before touching the PCB.

• Extended reset: Unplug the dehumidifier for at least 15–20 minutes to allow capacitors to discharge and the control to fully reset. Plug back in and test.
• Check power source: Plug the unit directly into a properly grounded wall outlet (no extension cords or power strips). Verify correct voltage with another appliance.
• Inspect PCB connections: Remove the control housing and visually inspect the main PCB. Ensure all harnesses are fully seated. Look for burn marks, bulging components, or corrosion.
• Surge protection: If E9 occurred after a storm or outage, consider using a surge protector in the future. However, if the board is already damaged, this will not clear the current error.
• Board replacement: If E9 persists after reset and there is no visible wiring issue, the main control board’s memory is likely corrupted. Replace the main control board with the correct Haier part number. This repair is typically best handled by a technician.