A defective attic exhaust can lead to abnormally hot temperatures in your home because hot air in the attic is not allowed to escape. In most cases, a defective attic exhaust fan is due to a worn-out or damaged motor. Fortunately, replacing the motor in an attic exhaust fan is a simple task that most people can do themselves. Follow this simple how-to guide to learn how to replace the motor in your attic exhaust fan.
Step 1 - Cut Power to Attic Exhaust Fan
Before you begin, make sure that you cut the power to the attic fan. Locate the correct circuit breaker and switch it to the off position.
Step 2 - Remove the Fan
Remove the screws or bolts that hold the attic exhaust fan in place. You will need to clip the wiring that powers the attic exhaust fan. However, before you do so, open the cover of the exhaust fan motor and use a test light or multimeter to ensure that no power is running to the unit.
Step 3 - Remove the Motor
Once you are sure the electrical current to the fan is off, you can remove the motor. You will probably need to remove the blade of the fan from the rotor first. After that, you can just remove a few screws and take out the motor.
Step 4 - Purchase Replacement Motor
Visit an electrical hardware supply store. Most local home improvement centers will not have the motor you need to repair your exhaust fan. In order to properly match up the motor, take the old one with you when you go to the store.
If your home uses a very old attic exhaust fan, a replacement motor may not be available. In that case, you will need to buy a new exhaust fan.
Step 5 - Wire in the New Motor
Using wire strippers, strip the ends of the wires that you cut when you removed the old attic exhaust fan motor. Next, strip the ends of the wires of the new motor. Match the colors of the wires and then twist the ends of the bare wires together. Shield the twisted wiring connections with wire caps. Apply penetrating spray to the rotor.
Step 6 - Re-install the Attic Exhaust Fan
Replace the attic exhaust fan and secure it with the screws or bolts that you removed earlier.
Step 7 - Turn On Power and Use Fan
Turn the power back on and begin using the attic exhaust fan.