To troubleshoot an exhaust fan, inspect the light to determine if the culprit is a wiring issue or a problem with circuit breakers. If an exhaust fan is too noisy and not sucking air effectively, test the fan using a piece of toilet paper.
In combination systems with an affixed light fixture, a wiring or circuit breaker problem may cause a nonfunctioning exhaust fan. Check if the light doesn’t turn on even if the light bulb isn’t burned out. To do this, remove the grill and fan cover from the fan, and examine the power cord connected to the motor. Unplug the cord for 30 seconds, plug it back, and switch on the breaker.
If the exhaust fan still doesn’t work, use a voltage meter to determine if the fan is receiving the required 120 volts. Inspect the breakers if the fan isn’t obtaining enough voltage. The fan motor may need replacement if it is getting sufficient voltage but fails to operate properly.
To troubleshoot a noisy exhaust fan that doesn’t suck air properly, hold a piece of toilet paper or paper towel against the grill while the fan is turned on. If the paper falls even if the motor is running, clean the motor and blow wheel to get rid of accumulated dust and lint, as the problem is likely a clogged or damaged exhaust line.