Once the weather starts to cool off, you are probably thinking about how you’ll take full advantage of your heating and cooling. After all, HVAC expenses frequently make up a large chunk of your monthly electric bill. To try and find ways to reduce costs, some people take a closer look at their thermostat. Maybe there’s a setting they should use to improve efficiency?

The majority of thermostats come with a ‘Fan’ or ‘Fan On’ setting. But if the fan is running during a typical cycle, what does the fan setting offer for your HVAC system? This guide will help. We’ll share just what the fan setting is and when you can use it to cut costs in the summer or winter.

My Thermostat Has a Fan Setting?

For the majority of thermostats, the fan setting signifies that the air handler’s blower fan stays on. Certain furnaces may continue to operate at a low level in this setting, but in most cases heating or cooling isn’t being generated. The ‘Auto’ setting, in contrast, will start the fan through a heating or cooling cycle and shut it off once the cycle is finished.

There are pros and cons to switching on the fan setting on your thermostat, and whether you do or don’t {will|can|should]] depend on your personal comfort preferences.

Advantages to trying the Fan/On setting:

  • You can keep the temperature throughout your home more balanced by enabling the fan to keep generating airflow.
  • Indoor air quality should improve because constant airflow will keep forcing airborne particles through the air filter.
  • A smaller number of start-stop cycles for the HVAC fan helps extend its life span. As the air handler is often part of the furnace, this means you can avoid needing furnace repair.

Drawbacks to switching to the Fan/On setting:

  • A nonstop fan could add to your energy costs slightly.
  • Constant airflow may clog your air filter up more quickly, 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 may stick around in unfinished spaces such as the attic or an attached garage. If you leave the fan on, your HVAC system can draw this warm air into the rest of your home, compelling the HVAC system to work more to maintain the set temperature. In severe heat, this can lead to needing AC repair more regularly as wear and tear grows.

The reverse can happen during the winter. Cooler spaces like a basement will hold onto cooler air, which will eventually flow into the rest of your home. Leaving the fan setting on could draw more cold air upward, increasing the amount of heating you need to stay warm.

If you’re still trying to figure out if you should use the fan/on setting, remember that every home and family’s comfort needs are different. Leaving the HVAC system’s fan on might be ideal for you if:

Someone in your household has allergies. Allergies and similar respiratory conditions can be stressful on the family. Leaving the fan on should help to enhance indoor air quality, helping your family breathe easier.

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