Dead Motor or Switch
If you notice that the switch to the exhaust fan doesn’t work, you can try one classic fix: removing the cover and plugging in a different appliance to test it. If the appliance won’t turn on, then the switch needs repairing. But if the device does work, then your switch is fine – it’s just the motor that needs replacing.
Vent Pipe Issues
Your exhaust fan’s vent pipe could be the culprit if it’s not functioning properly. The vent pipe is what keeps excess moisture out of your home and could therefore build up with mold or mildew over time. If the pipe appears plugged, then the exhaust fan won’t be able to do the job of removing humidity and condensation. The vent pipe can typically be found on the side of your house.
Dirty Fan Or Blower Wheel
The exhaust fan makes a quiet humming noise when it’s running properly. It’s something you may not notice until it either stops working, or it’s completely quiet. Chances are, the motor is dirty and needs the dust and dirt cleaned out. Not only will this improve the fan’s function, but you don’t want that debris blowing through your house, getting breathed in by your family, your pets, and your guests. A brush attachment on a vacuum should take care of it.
On the contrary, if your exhaust fan is a little too loud, that’s another sign that the wheel needs to be cleaned or replaced.