Once the weather is cooling off, you are probably thinking about how you’ll prepare your heating and cooling. After all, HVAC expenses routinely make up a large chunk of your monthly electric bill. To try and find ways to lower their HVAC bill, some people take a closer look at their thermostat. Is there a setting they can use to increase efficiency?

The majority of thermostats come with a ‘Fan’ or ‘Fan On’ setting. But if the fan is on during a typical cycle, what does the fan setting provide for your 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.

How Do I Access the Fan Setting on My Thermostat?

For the bulk of thermostats, the fan setting indicates that the air handler’s blower fan remains on. Certain furnaces can run at a low level in this setting, but for the most part heating or cooling isn’t being generated. The ‘Auto’ setting, on the other hand, will turn on the fan through a heating or cooling cycle and switch it off once the cycle is finished.

There are advantages and disadvantages to trying the fan setting on your thermostat, and what’s ideal {will|can|should]] depend on your unique comfort needs.

Advantages to using the Fan/On setting:

  • You can keep the temperature in every room more balanced by permitting the fan to keep circulating air.
  • Indoor air quality can increase because continuous airflow will keep passing airborne contaminants into the air filter.
  • A smaller amount of start-stop cycles for the blower fan helps lengthen its life span. As the air handler is usually part of the furnace, this means you might avoid needing furnace repair.

Downsides to utilizing the Fan/On setting:

  • A nonstop fan will likely add to your energy bills by a small margin.
  • Constant airflow can clog your air filter soon, increasing the frequency you should replace it.

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

During the summer, warm air will sometimes stick around in unfinished spaces such as the attic or an attached garage. If you use the fan setting, your HVAC system can draw this warm air into the rest of your home, compelling the HVAC system to run longer to keep up with the preferred temperature. In serious heat, this may result in needing AC repair more quickly as wear and tear grows.

The opposite can take place over the winter. Cooler spaces such as a basement will hold onto cooler air, which may eventually flow into the rest of your home. Leaving the fan running could 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, don’t forget that every home and family’s comfort needs will vary. Leaving the HVAC system’s fan on could be ideal for you if:

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

Your home experiences hot and cold spots. All kinds of homes wrestle with stubborn hot and cold spots that quickly evolve to a temperature different from the rest of the house. The fan setting might help lessen these changes by consistently refreshing each room’s supply of air.