As the weather is cooling off, you might be wondering about how you’ll take full advantage of your heating and cooling. After all, HVAC bills frequently add up to a big piece of your monthly electric bill. To learn new ways to reduce costs, some homeowners take a closer look at their thermostat. Is there a setting they can use to boost efficiency?

The majority of thermostats come with a ‘Fan’ or ‘Fan On’ setting. But if the fan is on during a normal cycle, what will the fan setting provide for the HVAC system? This guide should help. We’ll share what exactly the fan setting is and how you can use it to save money over the summer or winter.

Should I Use My Thermostat's Fan Setting?

For most thermostats, the fan setting means that the HVAC blower fan remains on. A few furnaces will operate at a low level with this setting, but for the most part heating or cooling isn’t being generated. The ‘Auto’ setting, conversely, will run the fan during a heating or cooling cycle and turn it off once the cycle is finished.

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

Advantages to utilizing the Fan/On setting:

  • You can keep the temperature throughout your home more balanced by permitting the fan to keep circulating air.
  • Indoor air quality should improve because constant airflow will keep moving airborne contaminants into the air filter.
  • A smaller number of start-stop cycles for the blower fan helps extend its life span. As the air handler is usually connected to the furnace, this means you could avoid needing furnace repair.

Downsides to switching to the Fan/On setting:

  • A constant fan can add to your energy expenses by a small margin.
  • Constant airflow can 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

In the summer, warm air will sometimes persist in unfinished spaces such as 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, compelling the HVAC system to run longer to maintain the desired temperature. In severe heat, this may lead to needing AC repair more regularly as wear and tear grows.

The reverse can occur in the winter. Cooler spaces like a basement will hold onto cooler air, which may eventually drift into the rest of your home. Keeping the fan on could pump more cold air upward, increasing the amount of heating you need to remain warm.

If you’re still trying to decide if you should use 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 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 increase indoor air quality, helping your family breathe easier.

Your home deals with 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 can help limit these changes by steadily refreshing each room’s airflow.