Once the weather starts to cool off, you are probably concerned about how you’ll prepare your heating and cooling. After all, HVAC expenses frequently make up a significant portion of your monthly electric bill. To figure out new ways to lower their HVAC bill, some homeowners look closely at their thermostat. Could there be a setting they can 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 save money during the summer or winter.

Should I Use My Thermostat’s Fan Setting?

For the bulk of thermostats, the fan setting signifies that the system’s blower fan keeps running. 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, in contrast, will turn on the fan through 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 whether you do or don’t {will|can|should]] depend on your unique comfort needs.

Advantages to trying the Fan/On setting:

  • You can keep the temperature in every room more uniform by enabling the fan to keep generating airflow.
  • Indoor air quality will be highest since continuous airflow will keep passing airborne pollutants through the air filter.
  • A smaller number of start-stop cycles for the system’s fan helps extend its life span. Since the air handler is typically a component of the furnace, this means you can minimize the risk of needing furnace repair.

Downsides to utilizing the Fan/On setting:

  • A continuous fan will likely raise your energy bills slightly.
  • Continuous airflow can clog your air filter soon, increasing the frequency you should replace it.

{Choosing Between|Should My Thermostat Be on|Which Setting for My Thermostat? Fan or Auto in Each Season

In the summer, warm air can stick around in unfinished spaces like the attic or an attached garage. If you use the fan setting, 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 desired temperature. In severe heat, this may result in needing AC repair more regularly as wear and tear gets worse.

The reverse can happen during 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 setting on will sometimes 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, don’t forget that every home and family’s comfort needs are different. Leaving the HVAC system’s fan on might work for you if:

Someone in your household suffers from allergies. Allergies and other respiratory conditions can be hard on the family. Leaving the fan on is more likely to enhance 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 lessen these changes by steadily refreshing each room’s supply of air.