Schedule An Appointment

Fan On vs Auto: How to Pick the Right One When Setting Your Thermostat

  • June 29, 2015

Most thermostats have two fan settings: “on” and “auto.” Which is the best option for comfort and energy savings when setting your thermostat? Learn the pros and cons to help you decide.

Benefits of the “On” Setting

setting your thermostatBy leaving the fan on, air is constantly pulled through the filter, which results in cleaner indoor air. Heated and cooled air is more evenly distributed throughout the home, reducing uncomfortable hot and cold pockets. Fewer starts and stops may also help the fan last longer.

When “On” Doesn’t Make Sense

Leaving the fan running 24 hours a day isn’t an efficient choice. It can notably increase heating and cooling bills compared to using the “auto” setting and clog up the filter more quickly, since air is constantly moving through it.

In the winter, a constantly running fan makes rooms feel drafty, while in the summer, leaky, uninsulated ducts running in the attic or near exterior walls heat up when the air conditioner isn’t running. Leaving the fan on circulates this hot air into your home and may cause the air conditioner to cycle on more frequently.

Air conditioning also removes excess moisture to dehumidify the air. If the fan continues to blow once the cooling element turns off, this moisture circulates back into your home, resulting a clammy feeling.

The Bottom Line

Leaving the fan on all the time has more drawbacks than benefits. It’s clear that if comfort and energy savings are the goal, you should set the fan to “auto” so it only runs when the furnace or air conditioner is on. Reserve the “on” setting for short periods, such as while vacuuming or to temporarily circulate air around the home when it feels stuffy.

Learn more about choosing and setting your thermostat for the best results, as well as Comfort Services, Inc.’s Carrier thermostats, or call us at 866-357-4613.

Image Provided by Shutterstock.com