Can You Run An Attic Fan With The AC On? [And should you?]

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When it comes to your home’s care and keeping, you have a plethora of tools at your disposal. It’s hard to know, though, when it’s safe to use these tools simultaneously. Take, for example, your air conditioner and an attic fan. Is it a good idea to run your attic fan with your air conditioner on? We’ve researched the capability of running these appliances together to get an answer for you.

You can use your air conditioning and attic fan at the same time. If you do, you can save money and maintain a comfortable temperature throughout your home.

Attic fans are far from complicated additions to your home, but you may still find yourself reluctant to either install one or use the one you have. To ease your concerns, we’ve brought together all of the information you might need on attic fans. With these tips up your sleeve, you can start slashing your monthly energy bills while also exploring other avenues that may help you keep your home more comfortable.

An attic with wooden frame roof membranes with an attic skylight with fan, Can You Run An Attic Fan With The AC On? [And should you?]

Can You Run An Attic Fan With The AC On?

If you’re concerned about your monthly energy bills or just not sure how to use your attic fan, don’t worry. We’ve got you covered! It’s hard to know when’s the best time to run your attic fan. After all, most homeowners use their attics as additional storage spaces instead of as entertaining spaces. If you’re not up in your attic, then why would you ever need to use an attic fan?

Most of the time, you’ll want to try and use your attic fan to improve your home’s air circulation. That fan is one of many tools, as mentioned, that can help you make your home more comfortable both for yourself and for any guests.

Attic Fans Versus Whole House Fans

Are attic fans the most effective home cooling tools in your toolbox, though? After all, if you have a whole house fan, air conditioning, and an attic fan, you might not be sure which combination of options may make your home the most comfortable.

In general, HVAC systems that allow you to run the air conditioning in your home always help you cool the air present inside the house. The primary difference between attic fans and whole-house fans is how those systems interact with that newly-cooled air.

Whole House Fans

Whole house fans create negative pressure in your home. Put another way; these fans ensure that the air pressure inside of your home is lower than the air pressure outside of your home. Nature, which abhors a vacuum, will help your whole house fan bring outside air indoors. Once indoors, your HVAC system can cool that air by running it through your air conditioner.

As that new air circulates through your home, your attic will take on positive pressure. This means that the air pressure in your attic will be greater than the air pressure outside. In turn, the air in your attic – which, due to the nature of physics, will already be warmer than air elsewhere in your home – will cycle out of your house, allowing cooler air to take its place. Your whole-house fan can then take that air back in, cool it, and thus a cycle of cooling is created that’ll let you spend your time indoors more comfortably.

Even if you run your whole-house fan with the air conditioning off, the system will work to cool your home for you, provided that the temperature outdoors is cooler than indoor air.

The perks of working with a whole house fan include:

  • Lower energy bills when not paired with your air conditioner
  • Little to no noise produced
  • Long-lasting

Attic Fans

Compared to a whole house fan, an attic fan is a simple tool to understand. An attic fan is simply a fan that’s in a window or on the ceiling of your attic. You can turn these types of fans on manually and use them to keep air circulating both through your attic and throughout the rest of your home.

Attic fans don’t change the air pressure in your home all that much. Instead, they make sure that the hotter air that rises throughout your home escapes through your attic’s soffit vents or open windows.

A detailed photo of an asphalt roofing of a mansion

The perks of working with an attic fan include:

  • Lower energy bills when not working in tandem with your air conditioner
  • Improves the health and lifespan of your roofing

In some cases, you can have an HVAC system, a whole house fan, and an attic fan working on your behalf at the same time. However, you’ll only want these devices working in tandem on occasion.

When Should You Use An Attic Fan?

As mentioned, your attic fan helps you control the flow of air through your home. Then, you can choose to use your attic fan whenever you feel as though your home may need airing out. It’s in your best interest to have an attic fan running in intervals instead of in mass-bursts. Whenever you begin to feel uncomfortable, though or get ahead of a bit of bad weather, you can turn on your attic fan, open the vents in your home, and enjoy the improved circulation.

Can You Run An Attic Fan With Windows Closed?

You can run an attic fan with your attic and house windows closed if you so choose. However, if you do, you’ll want to make sure that the soffit vents in your attic and the vents in the rest of your home are open. Your attic fan needs, after all, to send the air it moves somewhere else. While an attic fan doesn’t work like a whole house fan, the fan’s movement can still redirect cooling air back down into the rooms you visit more frequently – but only, as mentioned, if you have your vents open. If you leave your vents closed, then the air throughout your home will become stagnant.

Two air ventilators spinning on a top of a roof

Can You Run An Attic Fan All Day?

You can run an attic fan all day if you want to, but note that it’s not always in your best interest. If you overwork your attic fan, it’s possible that some of the parts may loosen, making the whole thing dangerous to have in motion. Similarly, an overworked attic fan is going to run up your electric bill for the month, effectively undoing any benefit that running it on set intervals might provide you with.

It’s in your best interest, then, to make sure that you turn your attic fan off for at least part of the day. Try running your attic fan for four hours, turning it off for four, and then having it pick back up. Alternatively, if you leave the house to go to work, you can turn your attic fan off while you’re gone and have it resume its work once you come back home again.

Should You Run Your Attic Fan In The Summer and Winter?

Seasonal changes can see homeowners use their HVAC systems differently. What do the changing seasons mean for your attic fan, though?

Attic Fans in the Summer

Whether you have your air conditioner off or on during the summer, your attic fan can prove quite the boon on the hottest days of the year. As mentioned, these fans do not pull air into your home from the outdoors, like whole house fans do. Instead, as the weather warms up outside, they’ll make sure that the air inside of your home continues to flow. You may not benefit from an immediate breeze, but your home should still be more pleasant to be in as a result.

Attic Fans in the Winter

Come wintertime, it’s far more likely that you’ll have your heat on than you will your air conditioning. Even so, your attic fan can still come in handy. If you leave your attic fan on for a short burst of time every day, the air that your HVAC system warms on your behalf will make it to all corners of the house instead of just rising to settle in the attic.

In short, no matter the season, an attic fan ensures that you can more readily circulate the air in your home.

In Conclusion

Any homeowner looking to make her home more comfortable during the summer or the winter needs to use the tools available to her benefit. With that in mind, don’t hesitate to put your attic fan to work. You can run your attic fan in tandem with your air conditioner. In fact, if you want to try and reduce your monthly electric bill, you’re encouraged to. By running your attic fan consistently, you can improve the circulation of air throughout your home and make your space more comfortable for yourself and anyone who might come to visit you.

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