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 routinely make up a significant portion of your monthly electric bill. To learn new ways to save, some owners look closer at their thermostat. Maybe there’s a setting they should use to improve efficiency?

The bulk of thermostats have a ‘Fan’ or ‘Fan On’ setting. But if the fan is going during a regular cycle, what does the fan setting offer for your HVAC system? This guide can help. We’ll share precisely what the fan setting is and how you can use it to cut costs in the summer or winter.

How Do I Access the Fan Setting on My Thermostat?

For most thermostats, the fan setting signifies that the HVAC blower fan keeps running. Certain furnaces may continue to run at a low level with this setting, but in most cases heating or cooling isn’t being produced. The ‘Auto’ setting, in contrast, will start the fan over a heating or cooling cycle and turn it off when the cycle is complete.

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 unique comfort needs.

Advantages to trying the Fan/On setting:

  • You can keep the temperature throughout your home more consistent by permitting the fan to keep running.
  • Indoor air quality can increase since constant airflow will keep forcing airborne particles into the air filter.
  • Fewer start-stop cycles for the HVAC fan helps expand its life span. Because the air handler is typically part of the furnace, this means you could avoid needing furnace repair.

Downsides to using the Fan/On setting:

  • A nonstop fan will likely increase your energy bills by a small margin.
  • Continuous airflow could 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 Summer/Winter

Through the summer, warm air may persist in unfinished spaces like the attic or an attached garage. If you use the fan setting, your HVAC system might pull this warm air into the rest of your home, pushing the HVAC system to work more to preserve the preferred temperature. In severe heat, this can lead to needing AC repair more often as wear and tear gets worse.

The opposite can happen 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 could pull 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 try the fan/on setting, remember that every home and family’s comfort needs are not the same. Leaving the HVAC system’s fan on may work for you if:

Someone in your household deals with allergies. Allergies and similar respiratory conditions can be hard 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. Many homes deal with difficult hot and cold spots that quickly shift to a temperature different from the rest of the house. The fan setting can help minimize these changes by consistently refreshing each room’s ventilation.