As the weather begins to cool off, you are probably thinking about how you’ll prepare your heating and cooling. After all, HVAC bills routinely add up to a significant chunk of your monthly electric bill. To figure out new ways to reduce costs, some people look closer at their thermostat. Maybe there’s a setting they could use to boost efficiency?

The bulk of thermostats come with a ‘Fan’ or ‘Fan On’ setting. But if the fan is on during a typical cycle, what will the fan setting offer for an HVAC system? This guide can help. We’ll share precisely what the fan setting is and whether you can use it to cut costs during the summer or winter.

How Do I Access the Fan Setting on My Thermostat?

For the majority of thermostats, the fan setting means that the HVAC blower fan stays on. Some furnaces will operate at a low level in this setting, but for the most part heating or cooling isn’t being made. The ‘Auto’ setting, in contrast, will turn on the fan over a heating or cooling cycle and switch it off once the cycle is finished.

There are advantages and disadvantages to using 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 running.
  • Indoor air quality will be highest as continuous airflow will keep forcing airborne contaminants into the air filter.
  • Fewer start-stop cycles for the system’s fan helps lengthen its life span. Since the air handler is typically connected to the furnace, this means you might prevent the need for furnace repair.

Downsides to utilizing the Fan/On setting:

  • A continuous fan could raise your energy expenses somewhat.
  • Continuous airflow can 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 keep the fan running, your HVAC system might pull this warm air into the rest of your home, pushing the HVAC system to work more to keep up with the set temperature. In serious heat, this can result in needing AC repair more quickly as wear and tear increases.

The reverse can occur over 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 will sometimes 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 switch to the fan/on setting, remember 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 deals with allergies. Allergies and other respiratory conditions can be hard on the family. Leaving the fan on should help to increase indoor air quality, helping your family breathe easier.

Your home deals with hot and cold spots. All kinds of homes deal with stubborn hot and cold spots that quickly return 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.