Once the weather is cooling off, you may be wondering about how you’ll take full advantage of your heating and cooling. After all, HVAC costs can make up a big portion of your monthly electric bill. To learn new ways to reduce costs, some people take a closer look at their thermostat. Is there a setting they could use to increase efficiency?

The majority of thermostats include both a ‘Fan’ or ‘Fan On’ setting. But if the fan is running during a normal cycle, what will the fan setting offer for your HVAC system? This guide can help. We’ll review precisely what the fan setting is and when 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 means that the air handler’s blower fan stays on. A few furnaces may continue to generate heat at a low level in this setting, but for the most part heating or cooling isn’t being produced. The ‘Auto’ setting, on the other hand, will run the fan over a heating or cooling cycle and turn it off after the cycle is complete.

There are pros and cons to using the fan setting on your thermostat, and what’s ideal {will|can|should]] depend on your unique comfort preferences.

Advantages to trying the Fan/On setting:

  • You can keep the temperature throughout your home more uniform by permitting the fan to keep running.
  • Indoor air quality will be highest since continuous airflow will keep passing airborne particles into the air filter.
  • A smaller number of start-stop cycles for the HVAC fan helps expand its life span. As the air handler is typically connected to the furnace, this means you might prevent the need for furnace repair.

Downsides to using the Fan/On setting:

  • A nonstop fan can raise your energy bills somewhat.
  • Constant airflow could clog your air filter in a shorter amount of time, increasing the frequency you will want to replace it.

Should My Thermostat Be on? Fan or Auto in Summer/Winter

Through the summer, warm air can linger in unfinished spaces such as the attic or an attached garage. If you keep the fan running, your HVAC system can draw this warm air into the rest of your home, compelling the HVAC system to work more to keep up with the desired temperature. In severe heat, this could result in needing AC repair more quickly as wear and tear grows.

The opposite can take place during the winter. Cooler spaces like a basement will hold onto cooler air, which can eventually drift into the rest of your home. Keeping the fan on could draw more cold air upward, increasing the amount of heating you need to keep warm.

If you’re still trying to determine if you should try the fan/on setting, remember that every home and family’s comfort needs are different. Leaving the HVAC system’s fan on might work 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 deals with hot and cold spots. Many homes wrestle with stubborn hot and cold spots that quickly shift to a temperature different from the rest of the house. The fan setting should help limit these changes by constantly refreshing each room’s supply of air.