Why Is My Attic Fan Not Working? 10 Possible Reasons

Attic fans can work wonders at cooling your attic, which helps keep down the cooling cost for the rest of the house. But they can only do their job when they are working properly.

If you find that your attic fan isn’t doing what it should, it can be a frustrating experience. To help you out, here are 10 likely reasons that your attic fan might not be working properly, the common symptoms of each problem, and advice on troubleshooting.

The 10 Reasons Why Your Attic Fan Isn’t Working

1. Faulty Thermostat

If you find that your attic fan won’t turn on or off or doesn’t turn on at the right time, the problem might be with the thermostat. Attic fans typically have a thermostat so they don’t over-cool the attic or keep running when they should not.

When it stops working, it can shut down the entire fan. To fix the problem, you either need to replace the thermostat or bypass it entirely. Keep in mind that if you choose to bypass the thermostat, it’ll either be on or off all the time, and you will have to manually change it yourself.

2. Tripped Circuit Breaker

Many things can lead to a tripped attic circuit breaker. Perhaps something overloaded the system, or maybe there was a quick short. The circuit breaker protects the rest of the electrical system in your house and keeps anything from catching on fire.

Find the circuit breaker box, flip the tripped breaker, and see if the problem comes back. If it does, there’s a problem somewhere in the electrical system that you need to troubleshoot. But flipping the circuit breaker often fixes the problem!

3. Burned-Out Fan Motor

The attic fan is just like any other fan in that it has a motor that keeps it spinning when it’s on. Eventually, the motor can “burn up” and it’ll stop working. This happens when components inside the motor wear out and break down.

Sometimes, you can replace just the motor for an attic fan, and other times, you’ll need to replace the entire fan. It depends on its size. You can generally replace components on large fans, while you have to completely replace small ones.

4. Unbalanced Blades

This isn’t the most likely problem for attic fans, but it can happen, especially with older fans. As the blades spin, they occasionally hit obstacles, and enough of these small collisions can damage and throw off the balance of the blades.

These obstacles could be birds, leaves, branches, or just about anything else. This is likely the problem when the fan makes excessively loud noises when running or the entire fan wobbles when it’s on.

Unfortunately, if your attic fan has unbalanced blades, you’ll need to replace the blades to get everything back in order. If you can’t just buy the blades, you’ll need to replace the entire fan.

5. Worn-Out Bearings

Inside the attic fan are small bearings that help keep everything spinning smoothly. Typically, these small metal balls are surrounded by some sort of lubricant that enables them to spin freely.

This is a highly effective system that you can find in a wide range of applications. Over time, the lubricant and the bearings themselves wear out, and you will need to replace them. It depends on the type of attic fan that you have whether you can replace just the bearings or if it’s time to replace the entire fan.

6. Loose Screws

As your attic fan spins, it puts a great deal of stress and torque on many components. The components holding everything together are the screws. With enough vibrations, the screws can start to back out, and this will cause the entire fan to make loud noises and begin to wobble when it’s running.

The good news is that all you need to do is re-tighten the screws to make the problem go away. We also recommend using something like Loctite to help keep the screws from backing out again.

7. Lack of Lubrication

Anytime you have an appliance with moving components, a little lubrication will help it along. Something as simple as WD-40 can help with the exterior components, but for the internal ones, you might need something more specific.

If there’s a problem with the lubricant, the fan will usually start making loud noises. If you ignore the problem for too long, it’ll put too much stress on the other components, and they can begin to fail too.

8. Obstructed Intake or Exhaust Vents

The attic fan distributes air from one place to another. If you’re simply using the fan to move air in the attic, obstructed intake or exhaust vents aren’t likely the issue.

But if you’re using your attic fan to move air throughout large portions of the home, and the air simply isn’t moving, these might be the cause. Dust, debris, old air filters, or collapsed vents can create issues, so it’s hard to put a price or a difficulty level on the repairs.

9. Broken Fan Belt

If you hear a humming noise coming from the fan but nothing moves, there’s a good chance that the problem is a broken fan belt. Disconnect the power source from the fan, and remove the exterior casing.

If you see a snapped or damaged belt, that’s the problem. These belts typically last a long time, but they don’t last forever. If you have mechanical experience, you can replace them yourself.

10. Wiring Problems

For the attic fan to work correctly, electricity needs to get from one point to another without any problems. It involves a great deal of wiring, and there are many potential problems that could keep an attic fan from working the way that it should.

Wires can short, cross, or simply lead to the wrong place. Complicating matters further is that the exact symptoms of an electrical problem vary depending on what and where the problem is. It can be a pain to troubleshoot, but you can sometimes get lucky and the problem is obvious.

Conclusion

Don’t settle for an attic fan that isn’t working as it should. While you might not want to spend the money to fix it, the truth is that the longer you put it off, the more you will spend on your utilities each month.

Take the time to figure out what’s going on and if you can fix the problem. If you can’t, call a professional to help you.

Featured Image Credit: funeyes, Pixabay