As the weather starts to cool off, you are probably thinking about how you’ll make the most of your heating and cooling. After all, HVAC costs can add up to a large piece of your monthly electric bill. To learn new ways to reduce costs, some people look closer at their thermostat. Maybe there’s a setting they should use to increase efficiency?

The majority of thermostats have 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 walk through just what the fan setting is and whether 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 may continue to operate at a low level with this setting, but in most cases heating or cooling isn’t being produced. The ‘Auto’ setting, conversely, will start the fan during a heating or cooling cycle and shut it off after the cycle is finished.

There are pros and cons to using the fan setting on your thermostat, and the ideal option {will|can|should]] depend on your unique comfort requirements.

Advantages to utilizing the Fan/On setting:

  • You can keep the temperature in every room more uniform by enabling the fan to keep running.
  • Indoor air quality should improve as steady airflow will keep moving airborne particles through the air filter.
  • A smaller amount of start-stop cycles for the blower fan helps lengthen its life span. Since the air handler is often part of the furnace, this means you can avoid needing furnace repair.

Downsides to utilizing the Fan/On setting:

  • A continuous fan will likely increase your energy bills slightly.
  • Continuous 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 Each Season

During the summer, warm air can stick around in unfinished spaces including the attic or an attached garage. If you keep the fan running, your HVAC system might gradually move this warm air into the rest of your home, compelling the HVAC system to work harder to preserve the set temperature. In serious heat, this could lead to needing AC repair more regularly as wear and tear increases.

The opposite can occur during 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 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 try the fan/on setting, remember 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 enhance indoor air quality, helping your family breathe easier.

Your home experiences hot and cold spots. All kinds of homes deal 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 steadily refreshing each room’s supply of air.