As the weather begins to cool off, you might be thinking about how you’ll make the most of your heating and cooling. After all, HVAC bills frequently contribute a big portion of your monthly electric bill. To figure out new ways to save, some people take a closer look at their thermostat. Is there a setting they could use to improve efficiency?

Most thermostats include both a ‘Fan’ or ‘Fan On’ setting. But if the fan is going during a typical cycle, what will the fan setting offer for an HVAC system? This guide can help. We’ll share what exactly the fan setting is and whether you can use it to save money during the summer or winter.

My Thermostat Has a Fan Setting?

For the bulk of thermostats, the fan setting means that the air handler’s blower fan keeps running. Some furnaces can run at a low level in this setting, but for the most part heating or cooling isn’t being produced. The ‘Auto’ setting, in contrast, will turn on the fan through a heating or cooling cycle and turn it off after the cycle is finished.

There are benefits and drawbacks to switching on the fan setting on your thermostat, and whether you do or don’t {will|can|should]] depend on your distinct comfort needs.

Advantages to switching to the Fan/On setting:

  • You can keep the temperature in every room more consistent by enabling the fan to keep generating airflow.
  • Indoor air quality should improve as constant airflow will keep forcing airborne pollutants through the air filter.
  • Fewer start-stop cycles for the blower fan helps expand its life span. As the air handler is often a component of the furnace, this means you could minimize the risk of needing furnace repair.

Disadvantages to using the Fan/On setting:

  • A nonstop fan can increase your energy costs somewhat.
  • Continuous airflow can clog your air filter soon, increasing the frequency you’ll need to replace it.

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

During the summer, warm air may stick around in unfinished spaces like 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 set temperature. In extreme heat, this can lead to needing AC repair more quickly as wear and tear increases.

The reverse can happen in the winter. Cooler spaces such as a basement will hold onto cooler air, which can eventually flow into the rest of your home. Keeping the fan on will sometimes pump more cold air upward, increasing the amount of heating you need to remain warm.

If you’re still trying to decide if you should switch to the fan/on setting, keep in mind that every home and family’s comfort needs are different. Leaving the HVAC system’s fan on might be best 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 is more likely to enhance indoor air quality, helping your family breathe easier.

Your home deals with hot and cold spots. All kinds of homes wrestle with stubborn hot and cold spots that quickly evolve to a temperature different from the rest of the house. The fan setting might help lessen these changes by constantly refreshing each room’s ventilation.