As the weather begins to cool off, you might be thinking about how you’ll take full advantage of your heating and cooling. After all, HVAC bills routinely add up to a big portion of your monthly electric bill. To try and find ways to lower their HVAC bill, some homeowners look closer at their thermostat. Maybe there’s a setting they can use to increase efficiency?

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

What Is the Fan Setting on My Thermostat?

For the majority of thermostats, the fan setting means that the HVAC blower fan stays on. Some furnaces can run at a low level with this setting, but for the most part heating or cooling isn’t being produced. The ‘Auto’ setting, in contrast, will turn on the fan through a heating or cooling cycle and shut it off when the cycle is complete.

There are pros and cons to trying the fan setting on your thermostat, and the ideal option {will|can|should]] depend on your distinct comfort preferences.

Advantages to trying the Fan/On setting:

  • You can keep the temperature in every room more balanced by permitting the fan to keep running.
  • Indoor air quality should improve as continuous airflow will keep forcing airborne contaminants through the air filter.
  • A smaller amount of start-stop cycles for the HVAC fan helps expand its life span. As the air handler is often part of the furnace, this means you could prevent the need for furnace repair.

Drawbacks to using the Fan/On setting:

  • A nonstop fan could add to your energy bills slightly.
  • Continuous airflow can clog your air filter up more quickly, increasing the frequency you will want to 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 will sometimes linger in unfinished spaces including the attic or an attached garage. If you leave the fan on, 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 extreme heat, this may lead to needing AC repair more often as wear and tear increases.

The reverse can take place over the winter. Cooler spaces such as a basement will hold onto cooler air, which can eventually make its way into the rest of your home. Keeping the fan on may pump more cold air upward, increasing the amount of heating you need to remain warm.

If you’re still trying to decide if you should try the fan/on setting, remember that every home and family’s comfort needs will vary. Leaving the HVAC system’s fan on may be best for you if:

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

Your home deals with hot and cold spots. All kinds of homes deal with difficult hot and cold spots that quickly evolve to a temperature different from the rest of the house. The fan setting should help minimize these changes by consistently refreshing each room’s airflow.