Should I Run My AC Fan While I’m Away?

June 26, 2021

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Using your thermostat correctly can be to your best advantage to save both energy and money, and to protect your home’s interior.  Mainly, it is to create a comfortable environment while you’re living in the house. But what about when you travel? One question we’re often asked is “Should I run my AC fan while I’m away?”

Using Your AC Thermostat Fan Correctly

Your air conditioner has mainly two jobs: to cool your house and to dehumidify the air. And your thermostat has two fan settings: AUTO and ON.

AUTO:  When using the AUTO fan setting, your AC comes on only when the cooling system is activated. It draws moisture from the air that will condense on your cold evaporator coil and drain out through the condensate line and it helps to maintain a constant temperature in your home.

Benefits to using the AUTO fan setting include:

  • More cost effective. Your fan only comes on when the air conditioning unit is engaged. The fan runs the least amount of time at the lowest setting.
  • Better humidity control. Moisture drawn from the air has the chance to drain outside.
  • Longer HVAC life. With less stress on your HVAC unit, your system will have a longer life.

ON: By turning your thermostat fan to the ON setting, the fan will run continuously. This can help to continually circulate air throughout your home and helps to regulate temperature from room to room. It can also help reduce allergens and pollutants that may be present in the air, and can aid those with allergies or respiratory issues.

There are also drawbacks to running your AC fan continuously:

  • A higher electric bill. The average AC’s 500-watt fan can cost up to an extra $50 per month.
  • Reduced effectiveness in reducing humidity. When the AC fan runs all the time, the evaporator coil becomes warm and less effective in removing excess moisture from the air. You could be recirculating humid air throughout your home, which could encourage the growth of mold or mildew, damage your electronics, or cause structural damage to your home. In turn, the higher humidity could cause your AC unit to run more often. Mold and mildew are apt to grow when the humidity levels reach 50%.
  • More air filter changes. As air continually flows through your AC’s air filter, it draws in particles and dust, which can build up in and eventually clog your air filter. You will need to change your air filter more frequently.
  • Additional maintenance. When you run your AC fan continually, the chances of it wearing out or breaking increase.

Related: 12 Air Conditioning Tips for the Summer

Which AC Fan Setting Should I Use When I’m Away

When you are away from home for an extended period, it is best to set your thermostat fan to the AUTO setting.

Other things you can do to help your AC be more efficient include:

  • Closing blinds or drapes on windows not facing the street or adding thermal drapes. Keep shades and blinds as you normally would on front-facing windows as to not give passersby the impression that the house is unoccupied.
  • Add solar films to windows to improve efficiency.
  • Minimize air leaks. This will help maintain temperatures inside your home.

Have Questions About Your AC Fan? Hire Golden Rule Home Watch to Care for Your Home While You’re Away

Hire Golden Rule Home Watch When You’re Away Hiring a Home Watch service like Golden Rule Home Watch & Concierge ensures that your home, property and vehicles will be protected while you’re away for an extended period of time. To learn more about our services and fees, contact us today for a free initial consultation.

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