Once the weather starts to cool off, you may be thinking about how you’ll take full advantage of your heating and cooling. After all, HVAC expenses routinely add up to a significant piece of your monthly electric bill. To figure out new ways to lower their HVAC bill, some people take a closer look at their thermostat. Is there a setting they could use to boost efficiency?

Most thermostats include both a ‘Fan’ or ‘Fan On’ setting. But if the fan is running during a regular cycle, what does the fan setting offer for your HVAC system? This guide should help. We’ll share precisely what the fan setting is and when you can use it to reduce costs during the summer or winter.

How Do I Access the Fan Setting on My Thermostat?

For most thermostats, the fan setting indicates that the HVAC blower fan stays on. A few furnaces may continue to run at a low level in this setting, but for the most part heating or cooling isn’t being produced. The ‘Auto’ setting, conversely, will turn on the fan over a heating or cooling cycle and switch it off once the cycle is complete.

There are advantages and disadvantages to switching on the fan setting on your thermostat, and the ideal option {will|can|should]] depend on your unique comfort needs.

Advantages to using the Fan/On setting:

  • You can keep the temperature in each room more consistent by enabling the fan to keep circulating air.
  • Indoor air quality will be highest since steady airflow will keep passing airborne pollutants through the air filter.
  • A smaller number of start-stop cycles for the blower fan helps extend its life span. As the air handler is usually part of the furnace, this means you can prevent the need for furnace repair.

Downsides to utilizing the Fan/On setting:

  • A nonstop fan will likely add to your energy costs by a small margin.
  • Continuous airflow may clog your air filter in a shorter amount of time, increasing the frequency you should replace it.

{Choosing Between|Should My Thermostat Be on|Which Setting for My Thermostat? Fan or Auto in Summer/Winter

Through the summer, warm air can stick around in unfinished spaces such as the attic or an attached garage. If you use the fan setting, your HVAC system may gradually move this warm air into the rest of your home, compelling the HVAC system to work harder to keep up with the desired temperature. In serious heat, this could result in needing AC repair more quickly as wear and tear increases.

The opposite can happen over the winter. Cooler spaces like a basement will hold onto cooler air, which can eventually drift into the rest of your home. Leaving the fan setting on could pump more cold air upward, increasing the amount of heating you need to remain warm.

If you’re still trying to figure out if you should use the fan/on setting, don’t forget that every home and family’s comfort needs are not the same. Leaving the HVAC system’s fan on might work for you if:

Someone in your household suffers from allergies. Allergies and other respiratory conditions can be hard on the family. Leaving the fan on can help to enhance indoor air quality, helping your family breathe easier.

Your home has hot and cold spots. All kinds of homes deal with stubborn hot and cold spots that quickly return to a temperature different from the rest of the house. The fan setting can help limit these changes by consistently refreshing each room’s supply of air.