As the weather starts to cool off, you are probably wondering about how you’ll make the most of your heating and cooling. After all, HVAC bills can add up to a large portion of your monthly electric bill. To figure out new ways to save, some people take a closer look at their thermostat. Could there be a setting they could use to boost efficiency?

The bulk of thermostats include both a ‘Fan’ or ‘Fan On’ setting. But if the fan is running during a typical cycle, what does the fan setting provide for your HVAC system? This guide will help. We’ll share what exactly the fan setting is and whether you can use it to reduce costs in the summer or winter.

What Is the Fan Setting on My Thermostat?

For most thermostats, the fan setting indicates that the HVAC blower fan stays on. Certain furnaces may continue to generate heat at a low level in this setting, but in most cases heating or cooling isn’t being made. The ‘Auto’ setting, conversely, will run the fan over a heating or cooling cycle and shut it off after the cycle is finished.

There are benefits and drawbacks to using the fan setting on your thermostat, and the ideal option {will|can|should]] depend on your personal comfort preferences.

Advantages to using 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 because continuous airflow will keep forcing airborne contaminants through the air filter.
  • A smaller amount of start-stop cycles for the system’s fan helps extend its life span. Because the air handler is often part of the furnace, this means you might avoid needing furnace repair.

Downsides to using the Fan/On setting:

  • A nonstop fan will likely add to your energy expenses slightly.
  • Nonstop airflow may clog your air filter soon, increasing the frequency you should replace it.

{Choosing Between|Should My Thermostat Be on|Which Setting for My Thermostat? Fan or Auto in Each Season

Through the summer, warm air may persist in unfinished spaces including the attic or an attached garage. If you leave the fan on, your HVAC system may pull this warm air into the rest of your home, pushing the HVAC system to run longer to maintain the desired temperature. In extreme heat, this could result in 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 can eventually flow into the rest of your home. Keeping the fan 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 switch to 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 could be ideal for you if:

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

Your home experiences hot and cold spots. Lots of homes deal with stubborn hot and cold spots that quickly evolve to a temperature different from the rest of the house. The fan setting can help limit these changes by consistently refreshing each room’s airflow.