Once the weather starts to cool off, you might be thinking about how you’ll make the most of your heating and cooling. After all, HVAC costs can make up a significant chunk of your monthly electric bill. To learn new ways to reduce costs, some homeowners take a closer look at their thermostat. Maybe there’s a setting they should use to increase efficiency?

The bulk of 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 should help. We’ll review what exactly the fan setting is and how you can use it to cut costs over the summer or winter.

My Thermostat Has a Fan Setting?

For the majority of thermostats, the fan setting means that the system's blower fan remains on. Certain furnaces can operate at a low level in this setting, but for the most part heating or cooling isn’t being made. The ‘Auto’ setting, conversely, will start the fan during a heating or cooling cycle and shut it off once the cycle is finished.

There are advantages and disadvantages to trying the fan setting on your thermostat, and the ideal option {will|can|should]] depend on your unique comfort preferences.

Advantages to trying 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 will be highest as constant airflow will keep forcing airborne contaminants through the air filter.
  • A smaller amount of start-stop cycles for the system's fan helps expand its life span. Because the air handler is typically a component of the furnace, this means you can avoid needing furnace repair.

Drawbacks to switching to the Fan/On setting:

  • A continuous fan could raise your energy costs somewhat.
  • Constant airflow can 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 Each Season

During the summer, warm air may persist in unfinished spaces including the attic or an attached garage. If you keep the fan running, your HVAC system might pull this warm air into the rest of your home, forcing the HVAC system to work harder to keep up with the set temperature. In severe heat, this can lead to needing AC repair more quickly as wear and tear increases.

The opposite can take place over the winter. Cooler spaces such as a basement will hold onto cooler air, which can eventually drift into the rest of your home. Leaving the fan setting on could 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 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 could work for you if:

Someone in your household suffers from allergies. Allergies and other respiratory conditions can be tough on the family. Leaving the fan on can help to increase indoor air quality, helping your family breathe easier.

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