Dehumidifier display shows "HI" for humidity and may run continuously.

Safety: Unplug before opening the control panel.

Steps:

• Verify environment: Use a separate hygrometer to confirm actual room humidity. In very damp spaces, HI may be accurate and not a fault.
• Check for condensation: If the sensor is wet from condensation or cleaning, allow it to dry completely and then test again.
• Clean sensor area: Gently clean dust from the humidity sensor vents using compressed air.
• Inspect wiring: Ensure the humidity sensor harness is not pinched or shorted and is fully seated on the control board.
• Replace sensor: If HI is displayed in a normal‑humidity room and does not change, replace the humidity sensor assembly.

Tip: After replacement, verify that the displayed humidity changes when you move the unit between a dry and a damp room.