Safety: Unplug the humidifier and empty the tank before working on the base.

Steps:

Check water level and tank seating: Ensure the tank is full and properly seated. Confirm that any low-water indicator is not active.
Inspect the ultrasonic membrane: Look into the base where the mist is generated. The round metal disc (transducer) should be clean and intact.
Descale the transducer: If you see white mineral deposits, soak the area with BONECO descaler or a 1:1 vinegar-water solution for 20–30 minutes. Gently clean with a soft brush. Do not scratch the disc.
Test operation: Refill and restart. If there is still no mist but the fan runs, the transducer or its driver circuit may have failed.
Replace the transducer module: Many BONECO ultrasonic models use a replaceable ultrasonic nebulizer / transducer module. Remove the screws holding the module, disconnect its wires, and install the new module, ensuring a watertight seal.
If a new transducer does not fix it: The main PCB ultrasonic driver is likely defective and will need replacement by a service center.

Humidifier powers on but produces no mist

Possible Causes