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 costs routinely contribute a significant chunk of your monthly electric bill. To learn new ways to reduce costs, some people take a closer look at their thermostat. Is there a setting they can use to boost efficiency?

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

How Do I Access the Fan Setting on My Thermostat?

For the bulk of thermostats, the fan setting means that the air handler’s blower fan stays on. Some furnaces can generate heat at a low level in this setting, but in general heating or cooling isn’t being generated. The ‘Auto’ setting, in contrast, will run the fan through a heating or cooling cycle and turn it off after the cycle is complete.

There are pros and cons to trying the fan setting on your thermostat, and what’s ideal {will|can|should]] depend on your distinct comfort needs.

Advantages to switching to the Fan/On setting:

  • You can keep the temperature in every room more balanced by enabling the fan to keep circulating air.
  • Indoor air quality will be highest as constant airflow will keep passing airborne pollutants into the air filter.
  • A smaller number of start-stop cycles for the HVAC fan helps expand its life span. Because the air handler is often connected to the furnace, this means you might minimize the risk of needing furnace repair.

Downsides to using the Fan/On setting:

  • A constant fan could add to your energy expenses by a small margin.
  • Constant airflow could clog your air filter up more quickly, increasing the frequency you will want to replace it.

{Choosing Between|Should My Thermostat Be on|Which Setting for My Thermostat? Fan or Auto in Summer/Winter

During the summer, warm air can stick around in unfinished spaces such as 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, forcing the HVAC system to work more to maintain the set temperature. In severe heat, this may lead to needing AC repair more quickly as wear and tear increases.

The opposite can occur over the winter. Cooler spaces such as a basement will hold onto cooler air, which will eventually flow into the rest of your home. Leaving the fan setting on may pump more cold air upward, increasing the amount of heating you need to remain warm.

If you’re still trying to figure out if you should switch to the fan/on setting, keep in mind 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 has allergies. Allergies and other respiratory conditions can be hard on the family. Leaving the fan on can help to improve indoor air quality, helping your family breathe easier.

Your home has hot and cold spots. Lots of homes wrestle with persistent hot and cold spots that quickly return to a temperature different from the rest of the house. The fan setting can help minimize these changes by consistently refreshing each room’s supply of air.