When the weather starts to cool off, you may be wondering about how you’ll make the most of your heating and cooling. After all, HVAC expenses routinely make up a significant piece of your monthly electric bill. To learn new ways to lower their HVAC bill, some owners look closer at their thermostat. Could there be a setting they should use to improve efficiency?

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

What Is the Fan Setting on My Thermostat?

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 in this setting, but for the most part heating or cooling isn’t being produced. The ‘Auto’ setting, on the other hand, will run the fan during a heating or cooling cycle and turn it off once the cycle is over.

There are benefits and drawbacks to switching on the fan setting on your thermostat, and the ideal option {will|can|should]] depend on your personal comfort requirements.

Advantages to trying the Fan/On setting:

  • You can keep the temperature in each room more consistent by allowing the fan to keep circulating air.
  • Indoor air quality should improve as steady airflow will keep passing airborne contaminants through the air filter.
  • A smaller amount of start-stop cycles for the blower fan helps extend its life span. Because the air handler is usually connected to the furnace, this means you can prevent the need for furnace repair.

Downsides to using the Fan/On setting:

  • A constant fan will likely raise your energy expenses by a small margin.
  • Continuous airflow could clog your air filter soon, 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 may persist in unfinished spaces like 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 preserve the preferred temperature. In severe heat, this can result in needing AC repair more regularly as wear and tear grows.

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

If you’re still trying to decide if you should use 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 deals with allergies. Allergies and similar respiratory conditions can be hard on the family. Leaving the fan on should help to increase indoor air quality, helping your family breathe easier.

Your home experiences hot and cold spots. Lots of homes wrestle with stubborn hot and cold spots that quickly shift to a temperature different from the rest of the house. The fan setting should help limit these changes by constantly refreshing each room’s ventilation.