The part(s) or condition(s) listed below for the symptom Dehumidifier fan not working 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.
The fan blade might be bent or broken. To check the fan blade, try turning the fan blade by hand. Ensure that the blade is not rubbing against the fan housing as it turns. If the fan blade does not turn freely or is rubbing against the fan housing, this indicates that the fan blade is defective and should be replaced. In addition, wiggle the fan motor shaft to see if the motor shaft is loose. If the fan motor shaft moves even slightly, this indicates that the fan blade is loose. If the fan blade is loose, tighten the set screw. If tightening the screw doesn’t solve the problem, replace the fan blade.
First, try turning the fan blade by hand to ensure that it spins freely. Make sure that the fan blade is not rubbing against the fan housing. If the fan blade spins freely and is not rubbing against the fan housing, use a multimeter to determine if the fan motor is getting power. If the fan motor is getting power, but the dehumidifier fan won’t run, the fan motor is likely defective. If the fan motor is defective, replace it.
Try turning the blower wheel by hand. If the blower wheel does not turn freely, or is rubbing against the fan housing, replace the blower wheel. In addition, if the blower wheel wobbles as it turns, this indicates that it is loose on the motor shaft. If the blower wheel is loose, tighten or replace it. Finally, if the blower wheel is physically damaged, replace it.
The humidity sensor monitors the level of moisture in the air. When the moisture level is too high, the contacts in the humidity sensor close to allow the dehumidifier to run. If the humidity sensor is defective, the dehumidifier fan will not run. If the humidity sensor is defective, replace it.