When the weather starts to cool off, you may be thinking about how you’ll make the most of your heating and cooling. After all, HVAC expenses can contribute a significant chunk of your monthly electric bill. To figure out new ways to save, some homeowners look closely at their thermostat. Is there a setting they should use to boost efficiency?

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

Should I Use My Thermostat's Fan Setting?

For most thermostats, the fan setting indicates that the HVAC blower fan keeps running. A few furnaces may continue to operate at a low level in this setting, but in general heating or cooling isn’t being made. The ‘Auto’ setting, in contrast, will start the fan during a heating or cooling cycle and switch it off when the cycle is over.

There are pros and cons to trying the fan setting on your thermostat, and whether you do or don’t {will|can|should]] depend on your distinct comfort preferences.

Advantages to trying the Fan/On setting:

  • You can keep the temperature in each room more uniform by permitting the fan to keep running.
  • Indoor air quality should improve as steady airflow will keep moving airborne particles into the air filter.
  • Fewer start-stop cycles for the blower fan helps lengthen its life span. Because the air handler is often a component of the furnace, this means you might avoid needing furnace repair.

Disadvantages to utilizing the Fan/On setting:

  • A continuous fan can increase your energy expenses slightly.
  • Continuous airflow may clog your air filter up more quickly, 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 persist in unfinished spaces including the attic or an attached garage. If you leave the fan on, your HVAC system can draw this warm air into the rest of your home, pushing the HVAC system to work harder to preserve the desired temperature. In extreme heat, this can lead to needing AC repair more often as wear and tear increases.

The reverse can occur over the winter. Cooler spaces such as 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 pump 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, remember that every home and family’s comfort needs will vary. Leaving the HVAC system’s fan on might work for you if:

Someone in your household suffers from allergies. Allergies and other 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 experiences hot and cold spots. Many homes deal with persistent hot and cold spots that quickly shift to a temperature different from the rest of the house. The fan setting might help minimize these changes by constantly refreshing each room’s airflow.