When the weather is cooling off, you are probably concerned about how you’ll prepare your heating and cooling. After all, HVAC expenses can contribute a significant piece of your monthly electric bill. To try and find ways to reduce costs, some homeowners take a closer look at their thermostat. Is there a setting they should use to improve efficiency?

Most thermostats include both a ‘Fan’ or ‘Fan On’ setting. But if the fan is on during a regular cycle, what can the fan setting provide for an HVAC system? This guide can help. We’ll share what exactly the fan setting is and when you can use it to reduce costs during the summer or winter.

My Thermostat Has a Fan Setting?

For most thermostats, the fan setting indicates that the HVAC blower fan remains on. A few furnaces may continue to operate at a low level with this setting, but for the most part heating or cooling isn’t being generated. The ‘Auto’ setting, in contrast, will run the fan during a heating or cooling cycle and shut it off after the cycle is complete.

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

Advantages to switching to the Fan/On setting:

  • You can keep the temperature in every room more consistent by permitting the fan to keep circulating air.
  • Indoor air quality will be highest because continuous airflow will keep forcing airborne contaminants through the air filter.
  • A smaller amount of start-stop cycles for the system’s fan helps expand its life span. Since the air handler is typically a component of the furnace, this means you could avoid needing furnace repair.

Downsides to using the Fan/On setting:

  • A nonstop fan can raise your energy bills slightly.
  • Continuous airflow could clog your air filter in a shorter amount of time, increasing the frequency you’ll need to replace it.

Should My Thermostat Be on? 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 use the fan setting, your HVAC system may gradually move this warm air into the rest of your home, forcing the HVAC system to run longer to maintain the desired temperature. In serious heat, this may lead to needing AC repair more quickly as wear and tear grows.

The reverse can take place over the winter. Cooler spaces like a basement will hold onto cooler air, which will eventually make its way into the rest of your home. Leaving the fan setting on may 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 try the fan/on setting, keep in mind that every home and family’s comfort needs are different. Leaving the HVAC system’s fan on could be best for you if:

Someone in your household suffers from allergies. Allergies and similar respiratory conditions can be hard on the family. Leaving the fan on is more likely to enhance indoor air quality, helping your family breathe easier.

Your home has hot and cold spots. Lots 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 should help lessen these changes by consistently refreshing each room’s supply of air.