Once the weather starts to cool off, you may be wondering about how you’ll take full advantage of your heating and cooling. After all, HVAC expenses can make up a large portion of your monthly electric bill. To figure out new ways to reduce costs, some homeowners look closer at their thermostat. Maybe there’s a setting they can use to boost efficiency?

The bulk of thermostats have a ‘Fan’ or ‘Fan On’ setting. But if the fan is on during a typical cycle, what can the fan setting offer for your HVAC system? This guide should help. We’ll review precisely what the fan setting is and whether you can use it to reduce costs in the summer or winter.

What Is the Fan Setting on My Thermostat?

For the majority of thermostats, the fan setting indicates that the air handler’s blower fan stays on. A few furnaces may continue to operate at a low level with this setting, but in most cases heating or cooling isn’t being made. The ‘Auto’ setting, on the other hand, will run the fan over a heating or cooling cycle and shut it off once the cycle is over.

There are benefits and drawbacks to trying the fan setting on your thermostat, and whether you do or don’t {will|can|should]] depend on your personal comfort needs.

Advantages to utilizing the Fan/On setting:

  • You can keep the temperature in each room more uniform by permitting the fan to keep circulating air.
  • Indoor air quality can increase as constant airflow will keep passing airborne pollutants through the air filter.
  • A smaller amount of start-stop cycles for the HVAC fan helps lengthen its life span. Because the air handler is often part of the furnace, this means you could minimize the risk of needing furnace repair.

Disadvantages to using the Fan/On setting:

  • A constant fan will likely raise your energy bills somewhat.
  • Continuous airflow could clog your air filter up more quickly, increasing the frequency you should replace it.

Should My Thermostat Be on Fan or Auto in Summer/Winter

In the summer, warm air can linger in unfinished spaces including the attic or an attached garage. If you leave the fan on, your HVAC system can gradually move this warm air into the rest of your home, compelling the HVAC system to run longer to keep up with the preferred temperature. In severe heat, this can result in needing AC repair more quickly as wear and tear increases.

The opposite can occur over the winter. Cooler spaces like a basement will hold onto cooler air, which will eventually flow into the rest of your home. Leaving the fan running will sometimes pull more cold air upward, increasing the amount of heating you need to remain warm.

If you’re still trying to figure out 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 has allergies. Allergies and other respiratory conditions can be stressful on the family. Leaving the fan on is more likely to enhance indoor air quality, helping your family breathe easier.

Your home deals with hot and cold spots. All kinds of homes wrestle with persistent hot and cold spots that quickly shift to a temperature different from the rest of the house. The fan setting should help lessen these changes by consistently refreshing each room’s supply of air.