When the weather is cooling off, you may be thinking about how you’ll take full advantage of your heating and cooling. After all, HVAC costs can add up to a large piece of your monthly electric bill. To figure out new ways to save, some homeowners look closer at their thermostat. Maybe there’s a setting they can use to boost efficiency?

The majority of thermostats have a ‘Fan’ or ‘Fan On’ setting. But if the fan is going during a normal cycle, what does the fan setting provide for an HVAC system? This guide can help. We’ll share just what the fan setting is and whether you can use it to save money over the summer or winter.

My Thermostat Has a Fan Setting?

For the majority of thermostats, the fan setting means that the air handler’s blower fan keeps running. Some furnaces will generate heat at a low level with this setting, but in general heating or cooling isn’t being produced. The ‘Auto’ setting, conversely, will run the fan through a heating or cooling cycle and turn it off when the cycle is over.

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

Advantages to utilizing the Fan/On setting:

  • You can keep the temperature throughout your home more consistent by enabling the fan to keep running.
  • Indoor air quality can increase as constant airflow will keep forcing airborne particles into the air filter.
  • Fewer start-stop cycles for the blower fan helps extend its life span. As the air handler is typically a component of the furnace, this means you could prevent the need for furnace repair.

Drawbacks to utilizing the Fan/On setting:

  • A nonstop fan will likely add to your energy costs by a small margin.
  • Nonstop airflow could clog your air filter in a shorter amount of time, 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 will sometimes 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 maintain the desired temperature. In serious heat, this can result in needing AC repair more quickly as wear and tear grows.

The reverse can take place in 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 draw 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, keep in mind that every home and family’s comfort needs will vary. Leaving the HVAC system’s fan on could be best 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 can help to increase indoor air quality, helping your family breathe easier.

Your home experiences hot and cold spots. Many homes wrestle with stubborn hot and cold spots that quickly return to a temperature different from the rest of the house. The fan setting might help limit these changes by steadily refreshing each room’s ventilation.