Should you keep furnace fan on

When your central air conditioner is running, you need the furnace fan to be on to distribute the cold air throughout your home. The AC and system fan work together. But savvy homeowners who turn their air conditioner off frequently to save money might not be sure what to do with the fan. Should you keep your furnace fan on when the AC is off? Will it cost you money, benefit your air quality, or make your home heat up faster? We’ll explain what happens when you keep the fan set to “on” and what you might choose to do about it.

Should the Furnace Fan be on “Auto” or “On”? Pros & Cons 

Generally, it depends on your priorities and your home. There are advantages and disadvantages to leaving the fan on or turning it off. By the way, leaving the fan on “auto” when the air conditioner is not running is the same as leaving it off. It will only come on when the air conditioner is on. 


 The advantages of turning the fan on when the air conditioner isn’t running include: 

  • Consistency: When the fan is running, it circulates air and therefore heat through your home. Every area will be the same temperature, without hot spots. 
  • Air quality: Carbon dioxide and airborne contaminants, including allergens, dust and pet hair, all collect in the air when it is not being cycled through your home. Keeping your fan running can improve your overall air quality. 
  • Lifespan: Starting and stopping are stressful on all electrical equipment, including fans. By leaving your fan on, you may reduce this damage and could extend its lifespan. 

Are you looking for an HVAC expert to improve your home’s air quality along with more energy savings? Call the team at Link ClimateCare today! 

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 The disadvantages of turning the fan on when the air conditioner isn’t running include: 

  • Cost: Your furnace fan doesn’t run for free. It can run you a cost of approximately only $1.00 a day though. 
  • Heat: The fan will get your home to an even temperature, but is that a good thing? Sometimes, if you hang out in the coldest part of your home during the summer, you don’t necessarily want to make it warmer with the fan. This will depend on your home’s layout, though. 
  • Filter use: Your filter will get dirty faster when you run your fan all the time, and you will need to replace it more often. 

How Often Should I Run HVAC Fans? 

It is our opinion when you install a new system from Link ClimateCare that you let your furnace fan run in the “on” position.  The pros outnumber the cons and it is worth it. 

Do you have other questions about how to improve your home’s air quality or how to make your air conditioning more energy efficient? Link ClimateCare can provide you with solutions and guidance. Reach out to us today. 

Article Updated 2024-01-24.

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