As the weather is cooling off, you are probably concerned about how you’ll take full advantage of your heating and cooling. After all, HVAC expenses can make up a significant piece of your monthly electric bill. To figure out new ways to lower their HVAC bill, some people look closely at their thermostat. Could there be a setting they should use to increase efficiency?

The bulk of thermostats include both a ‘Fan’ or ‘Fan On’ setting. But if the fan is on during a normal cycle, what will the fan setting provide for your HVAC system? This guide can help. We’ll review what exactly 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 most thermostats, the fan setting signifies that the system’s blower fan keeps running. Certain furnaces may continue to run at a low level with this setting, but in most cases heating or cooling isn’t being produced. The ‘Auto’ setting, in contrast, will run the fan during a heating or cooling cycle and switch it off when the cycle is finished.

There are benefits and drawbacks to using the fan setting on your thermostat, and whether you do or don’t {will|can|should]] depend on your unique comfort preferences.

Advantages to trying the Fan/On setting:

  • You can keep the temperature in every room more uniform by permitting the fan to keep running.
  • Indoor air quality will be highest as steady airflow will keep moving airborne pollutants 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 often a component of the furnace, this means you might minimize the risk of needing furnace repair.

Downsides to switching to the Fan/On setting:

  • A nonstop fan will likely raise your energy costs by a small margin.
  • Constant airflow may clog your air filter in a shorter amount of time, increasing the frequency you’ll need to replace it.

{Choosing Between|Should My Thermostat Be on|Which Setting for My Thermostat? Fan or Auto in Each Season

During the summer, warm air may persist in unfinished spaces like the attic or an attached garage. If you use the fan setting, your HVAC system might gradually move this warm air into the rest of your home, pushing the HVAC system to work harder to keep up with the preferred temperature. In serious heat, this can result in needing AC repair more often as wear and tear grows.

The reverse can occur over the winter. Cooler spaces like a basement will hold onto cooler air, which will eventually drift into the rest of your home. Keeping the fan on will sometimes 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 will vary. Leaving the HVAC system’s fan on might 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 should help to improve indoor air quality, helping your family breathe easier.

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