How to Fix / Troubleshooting

Safety: Unplug the humidifier. Do not touch the transducer while powered; it vibrates at ultrasonic frequency.

Steps:

Remove the water tank and inspect the ultrasonic transducer in the base (a small metal disc in a recess).
Clean the transducer surface gently with a cotton swab and white vinegar to remove mineral deposits. Do not scratch the disc.
Rinse and dry the area thoroughly before reassembling and testing.
If F2 persists and there is still no mist, the transducer or its driver circuit may have failed. Access the base and disconnect the transducer leads.
Test the transducer with a multimeter (it should show a finite impedance, not open). Replace the Dimplex ultrasonic transducer module if open or physically damaged.
If a new transducer does not restore operation, the main PCB driver stage is likely faulty and the control board should be replaced.

Humidifier shows F2; no mist output even with full tank

Possible Causes