Honeywell Humidifier Drum Won't Turn

The part(s) or condition(s) listed below for the symptom Humidifier drum won't turn are ordered from most likely to least likely to occur. Check or test each item, starting with the items at the top of the page.

Most Frequent Causes for Humidifier drum won't turn

For the most accurate results, enter your model number.

Cause 1Drive Motor

If the drum does not rotate and the drive motor is not turning, check to be certain the motor is getting power from the humidistat. If the motor is working but doesn't seem to have the strength to turn the drum, replace the drive motor. If the drive motor is clicking or only seems to spin the drum partway before giving up, replace the drive motor. If the humidifier drum won’t turn, the drive motor might be defective. First, make sure that the motor is getting power. If the motor Is getting power

Cause 2Control Board

The humidifier gets its power from the furnace control board. If no power is getting to the humidifier and you've determined the furnace control board needs to be replaced, you will have to use the furnace model number to get the correct part. The humidifier model number will only show parts specific to the humidifier.

Cause 3Transformer

Some furnaces have a separate transformer to provide voltage to the humidifier to turn the drum. If the humidifier is not receiving the proper voltage, but the contacts in the humidistat are closing as expected, it's likely the transformer has failed and the component will need to be replaced.

Cause 4Humidistat

If you've determined the humidifier's drum drive motor is functional but not receiving power, you should confirm the contacts in the humidistat close when the dial is set higher than the actual humidity in the room. You can use a multimeter to confirm the humidistat contacts are closing. If the contacts do not close as expected, the humidistat is defective and should be replaced.