When the weather is cooling off, you may be wondering about how you’ll take full advantage of your heating and cooling. After all, HVAC bills routinely make up a significant chunk of your monthly electric bill. To try and find ways to save, some homeowners take a closer look at their thermostat. Could there be a setting they could use to improve efficiency?

The bulk of thermostats come with a ‘Fan’ or ‘Fan On’ setting. But if the fan is running during a regular cycle, what does the fan setting offer for an HVAC system? This guide should help. We’ll share precisely what the fan setting is and whether you can use it to reduce costs over the summer or winter.

What Is the Fan Setting on My Thermostat?

For the bulk of thermostats, the fan setting means that the air handler’s blower fan stays 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 produced. The ‘Auto’ setting, in contrast, will start the fan during a heating or cooling cycle and shut it off when 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 distinct comfort preferences.

Advantages to using the Fan/On setting:

  • You can keep the temperature throughout your home more balanced by allowing the fan to keep circulating air.
  • Indoor air quality can increase as 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. Since the air handler is often part of the furnace, this means you can minimize the risk of needing furnace repair.

Disadvantages to switching to the Fan/On setting:

  • A continuous fan could raise your energy expenses somewhat.
  • Continuous 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

Through the summer, warm air may stick around in unfinished spaces including the attic or an attached garage. If you use the fan setting, your HVAC system can gradually move this warm air into the rest of your home, forcing the HVAC system to work harder to maintain the desired temperature. In extreme heat, this may result in needing AC repair more often as wear and tear increases.

The reverse can occur in 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 will sometimes pull more cold air upward, increasing the amount of heating you need to keep warm.

If you’re still trying to determine if you should switch to the fan/on setting, keep in mind that every home and family’s comfort needs are different. Leaving the HVAC system’s fan on may be ideal for you if:

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

Your home deals with hot and cold spots. All kinds of homes deal with persistent hot and cold spots that quickly shift to a temperature different from the rest of the house. The fan setting can help lessen these changes by steadily refreshing each room’s supply of air.