Humidifier display shows "Lo" and unit does not start misting.

Safety: Unplug the unit before removing the tank.

• Refill tank: Remove the tank, fill with clean, preferably demineralized water, and reinstall carefully.
• Check tank valve: Inspect the spring-loaded valve at the bottom of the tank. Ensure it moves freely and is not blocked by debris.
• Clean float: If your Medisana model uses a float in the base, clean it and the chamber with mild vinegar solution to remove scale.
• Sensor check: If "Lo" remains with a full tank and clean float, the water level sensor (float/reed or electronic) may be defective and should be replaced.