When the weather starts to cool off, you might be wondering about how you’ll make the most of your heating and cooling. After all, HVAC costs frequently add up to a significant portion of your monthly electric bill. To try and find ways to save, some people take a closer look at their thermostat. Maybe there’s a setting they should use to improve efficiency?

Most thermostats have a ‘Fan’ or ‘Fan On’ setting. But if the fan is going during a normal cycle, what will the fan setting offer for an HVAC system? This guide can help. We’ll walk through precisely what the fan setting is and how you can use it to cut costs over the summer or winter.

My Thermostat Has a Fan Setting?

For most thermostats, the fan setting indicates that the HVAC blower fan keeps running. Some furnaces will operate at a low level in this setting, but in general heating or cooling isn’t being produced. The ‘Auto’ setting, conversely, will run the fan during a heating or cooling cycle and shut it off once the cycle is complete.

There are advantages and disadvantages to using the fan setting on your thermostat, and what’s ideal {will|can|should]] depend on your personal comfort preferences.

Advantages to trying the Fan/On setting:

  • You can keep the temperature in each room more balanced by allowing the fan to keep generating airflow.
  • Indoor air quality should improve because steady airflow will keep passing airborne pollutants through the air filter.
  • A smaller amount of start-stop cycles for the system’s fan helps lengthen its life span. Because the air handler is typically connected to the furnace, this means you could prevent the need for furnace repair.

Drawbacks to utilizing the Fan/On setting:

  • A constant fan will likely add to your energy expenses somewhat.
  • Continuous airflow may 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

In the summer, warm air may persist in unfinished spaces including the attic or an attached garage. If you keep the fan running, your HVAC system might pull this warm air into the rest of your home, forcing the HVAC system to work harder to maintain the desired temperature. In serious heat, this may lead to needing AC repair more often as wear and tear grows.

The reverse can occur during the winter. Cooler spaces such as a basement will hold onto cooler air, which will eventually drift into the rest of your home. Leaving the fan setting on will sometimes pull more cold air upward, increasing the amount of heating you need to remain warm.

If you’re still trying to decide 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 be best for you if:

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

Your home has hot and cold spots. All kinds of homes wrestle with difficult hot and cold spots that quickly shift to a temperature different from the rest of the house. The fan setting can help limit these changes by constantly refreshing each room’s ventilation.