As the weather starts to cool off, you might be concerned about how you’ll take full advantage of your heating and cooling. After all, HVAC expenses frequently add up to a large piece of your monthly electric bill. To figure out new ways to reduce costs, some homeowners look closely at their thermostat. Is there a setting they should use to improve efficiency?

Most thermostats come with a ‘Fan’ or ‘Fan On’ setting. But if the fan is running during a regular cycle, what will the fan setting provide for your HVAC system? This guide will help. We’ll share just what the fan setting is and when you can use it to reduce costs in the summer or winter.

Should I Use My Thermostat's Fan Setting?

For most thermostats, the fan setting means that the HVAC blower fan stays on. Some furnaces may continue to generate heat at a low level with this setting, but in general heating or cooling isn’t being made. The ‘Auto’ setting, in contrast, will turn on the fan through a heating or cooling cycle and switch it off once the cycle is complete.

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

Advantages to utilizing the Fan/On setting:

  • You can keep the temperature throughout your home more uniform by allowing the fan to keep circulating air.
  • Indoor air quality can increase because steady airflow will keep passing airborne pollutants through the air filter.
  • Fewer start-stop cycles for the system's fan helps lengthen its life span. As the air handler is typically a component of the furnace, this means you might minimize the risk of needing furnace repair.

Downsides to utilizing the Fan/On setting:

  • A continuous fan could raise your energy bills slightly.
  • Constant airflow can clog your air filter soon, 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 Summer/Winter

Through the summer, warm air may linger in unfinished spaces such as the attic or an attached garage. If you use the fan setting, your HVAC system might pull this warm air into the rest of your home, compelling the HVAC system to work more to keep up with the desired temperature. In extreme heat, this can lead to needing AC repair more often as wear and tear gets worse.

The opposite can take place over the winter. Cooler spaces like a basement will hold onto cooler air, which will eventually make its way into the rest of your home. Keeping the fan on will sometimes pull more cold air upward, increasing the amount of heating you need to stay warm.

If you’re still trying to decide if you should try the fan/on setting, don’t forget that every home and family’s comfort needs are different. Leaving the HVAC system’s fan on may 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 can help to improve indoor air quality, helping your family breathe easier.

Your home deals with hot and cold spots. All kinds of homes wrestle with difficult hot and cold spots that quickly evolve to a temperature different from the rest of the house. The fan setting can help limit these changes by constantly refreshing each room’s ventilation.