Unit shows 'ADD WATER' even though the reservoir is full.

Safety: Unplug before cleaning sensors.

Correcting false low water:

• Clean probes/float: Use vinegar and a soft cloth to remove mineral deposits from metal probes or around the float.
• Verify float movement: Gently move the float up and down to ensure free travel.
• Check wiring: Confirm the sensor harness is connected securely to the control board.
• Replace sensor: If cleaning and wiring checks do not resolve the issue, replace the water level sensor or float switch assembly.