What Does An AC Fan Do?

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Updated February 2, 2023

It’s one thing to invest in the best air conditioner, and another to know how to use it properly. Today, we’ll take a look at what does a fan do on an AC and how to use the different modes correctly. This will help maintain air temperature, lower energy usage, and more.

There are several modes that air conditioning units are capable of having: Fan Mode, On Mode, and Auto Mode. Each provides different perks, like a cold temperature or a more energy-efficient operation.

  • Fan Mode: This mode allows you to provide consistent air circulation. It works by pulling air through the air filter and condenser unit and then sending it back throughout your household. While it won’t provide the same temperature lowering results as the active cooling mode, it’s great to keep the air feeling fresh.
  • On Mode: Also known as “Cool Mode,” this function will get those cold cooling coils working. If you want a cold temperature setting, then this is the mode you should go with. It’ll help you keep a nice, cold temperature in the house during those hot summer days. If you’re interested in exploring different models, look into what a mechanical air conditioner is and if it’s the right fit.
  • Auto Mode: The auto setting will allow your AC to turn on automatically so you can maintain a cool temperature throughout your home. On the other hand, the On Mode will tell the AC to keep running and circulating the air in your home even when it’s not trying to maintain a cold temperature. To learn how to troubleshoot your air conditioning units, read what F6 means on an air conditioner.


  • Understanding each air conditioner fan mode will help you do several things, including lowering energy costs and improving overall air quality.
  • There are a few main AC modes on an average unit, such as On, Fan, and Auto Mode.
  • Each mode does something a little different. While the On mode will continuously circulate air, the fan mode will only circulate air without cooling.

Why Air Conditioner Fans Are Important

While these AC fans can keep you cool and comfortable in your home, they can make an impact on your AC’s energy usage. Anybody involved with air conditioning services will tell you that a big part of lowering energy bills is understanding the function of an air conditioner fan. This is especially important during the summer months when energy consumption becomes a primary concern.

Insider Tip

If you perform regular maintenance on your air conditioning unit, you can avoid many serious problems.

If you’re curious about the different parts of your AC that keep the air fresh, try reading our article explaining what the air exchanger on an air conditioner is. And if you’re curious about learning more, try looking into what do the evaporator coils do.


Air conditioners can be the biggest energy hogs in your home, so take precautions to lower your energy needs.

STAT: The most populated U.S. states, such as Florida, Texas, and New York, had over 7,000 plumbing and HVAC contractor establishments in 2019. (source)

What Does the Fan Do on an AC FAQs

Are air conditioners suitable for people with allergies?

Yes, and central air conditioning systems can improve your symptoms. Because of the HVAC filters in the system, a lot of particulate matter is removed from your breathing supply.

Will a programmable thermostat work with my AC?

Digital thermostats have become wildly popular and will work with most systems. However, it depends on the system you have and which thermostat you’re looking to use.

How can I reduce hot and cold spots in my home?

The distribution of heating that happens throughout your home can be affected by the mode you choose to have your air conditioner on. Keep the fan motors moving if you want even cooling.

What steps can I take to lower indoor humidity?

Running your AC unit will actually help dehumidify the air in your home. This is because when air passes through the condenser coils, it removes excess moisture from the air to cool it.
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