Troubleshooting an Attic Fan

A close up on a fan.

An attic fan is a great way to keep your home cool during the hot summer months. The attic fan works by removing the superheated air from your attic so the air in your entire home can circulate and cool down. After the attic fan has been in use for some time, it may develop problems. Knowing how to troubleshoot common problems that could befall your fan will help you make simple repairs yourself and avoid hiring a repairman.

Won’t Turn On

Before you tear apart the fan, check the electrical connections. Look at the circuit breaker to make sure it is not tripped. If it automatically trips again after resetting it, you may have a short in the wires along the circuit.

Also, check the wire connections at the fan, at an electrical junction, or at an outlet box. If the attic fan is plugged into an outlet, use a voltmeter to make sure that the outlet is working. You may need to replace a circuit breaker, an electrical outlet, or one of the wire connections.

Fan Motor Runs but Not the Blades

If the motor is working but the fan blades are not moving, the problem may be the belt. Remove the outer casing of the attic fan and check to see if the belt is sagging, cracked, worn, or broken. If there is any damage to the belt, replace it with a new one.

Little or No Airflow

ceiling fans and vents

When running at a high-speed setting, does the attic fan run hard or sluggishly? If it is rotating slowly or not producing a lot of air in the high-speed setting, you may have a problem with the exhaust or intake. Check the intake for any debris. Also, make sure the exhaust of the attic fan is high and near the roof with no obstructions.

Annoying Humming Noise

An attic fan with a few blades may pick up a humming noise as it runs on a high-speed setting. The only way to get rid of this hum is to continually operate the fan on a low setting or replace the fan with a newer one with more blades.

Fan Shudders and Rattles

attic window

One of the problems that many people have with their attic fan is that it shakes and rattles. This is because it is not getting enough air. If you have a closed-off attic, install a window or open one on the other end. This will create a nice airflow and allow more air into the fan itself. Make sure the window is at least 30 feet away from the fan.

Burning Smell

If the fan emits a burning smell from the exhaust, there is a problem with the motor. Remove the motor and replace it. If the smell still remains, the belt could be slipping, or the gears that turn the blade shaft could need some grease.

With some basic tools and a little detective work, troubleshooting problems with your attic fan is an achievable DIY goal.