To find out if your bathroom ventilation fan is working properly, follow these steps:
- Turn the fan on and hold a tissue to the grill of the fan. If the tissue is held to the grill by the fan, then the fan is doing its job drawing air through the ventilation duct.
- To be sure that air is being exhausted properly, check the exhaust hood from the outside. Turn on the fan and place the open end of a plastic bag over the exhaust hood. An inflated bag is a sign that the air is being exhausted properly.
- If your fan is not drawing air or exhausting properly, you may need to replace the fan motor.
- Keep in mind that a bathroom fan should exhaust at a rate of at least 1 CFM (cubic feet per minute) per square foot. Bathrooms with large fixtures need more powerful or additional fans to vent air properly.
- Poor ductwork placement may also be responsible for exhaust malfunction.