Humidifier water tank is full but unit does not run; behaves as if empty

Steps:

• Check tank valve: Turn the tank upside down and press the spring-loaded valve. Water should flow freely. If not, clean or replace the valve assembly.
• Inspect tank seating: Ensure the tank sits correctly on the base and depresses any internal switch or pin.
• Check presence switch: Locate the tank presence micro-switch in the base and verify it actuates when the tank is installed.
• Replace faulty parts: Replace the tank valve assembly or tank presence switch as needed.