When the weather begins to cool off, you are probably thinking about how you’ll prepare your heating and cooling. After all, HVAC expenses routinely add up to a large portion of your monthly electric bill. To figure out new ways to reduce costs, some homeowners take a closer look at their thermostat. Is there a setting they should use to increase efficiency?

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

Should I Use My Thermostat’s Fan Setting?

For most thermostats, the fan setting means that the air handler’s blower fan keeps running. Some furnaces can run at a low level with this setting, but in most cases heating or cooling isn’t being made. The ‘Auto’ setting, conversely, will turn on the fan during a heating or cooling cycle and shut it off when the cycle is finished.

There are benefits and drawbacks 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 in each room more uniform by allowing the fan to keep generating airflow.
  • Indoor air quality will be highest since constant airflow will keep passing airborne pollutants through the air filter.
  • A smaller number of start-stop cycles for the system’s fan helps lengthen its life span. Since the air handler is usually part of the furnace, this means you can minimize the risk of needing furnace repair.

Drawbacks to utilizing the Fan/On setting:

  • A continuous fan can add to your energy costs somewhat.
  • Constant airflow could clog your air filter in a shorter amount of time, 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 Each Season

During the summer, warm air will sometimes persist in unfinished spaces including the attic or an attached garage. If you use the fan setting, your HVAC system can draw this warm air into the rest of your home, pushing the HVAC system to run longer to keep up with the desired temperature. In extreme heat, this may result in needing AC repair more regularly as wear and tear gets worse.

The reverse can take place over the winter. Cooler spaces such as a basement will hold onto cooler air, which can eventually flow 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 remain warm.

If you’re still trying to determine if you should use the fan/on setting, remember 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 deals with 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 deals with hot and cold spots. Lots of homes deal with persistent hot and cold spots that quickly return to a temperature different from the rest of the house. The fan setting can help limit these changes by consistently refreshing each room’s supply of air.