As the weather begins to cool off, you are probably wondering about how you’ll make the most of your heating and cooling. After all, HVAC costs frequently make up a big piece of your monthly electric bill. To figure out new ways to lower their HVAC bill, some people take a closer look at their thermostat. Maybe there’s a setting they should use to boost efficiency?

The majority of thermostats include both a ‘Fan’ or ‘Fan On’ setting. But if the fan is running during a normal cycle, what will the fan setting offer for the HVAC system? This guide can help. We’ll review precisely what the fan setting is and how you can use it to cut costs over the summer or winter.

What Is the Fan Setting on My Thermostat?

For the majority of thermostats, the fan setting means that the air handler’s blower fan stays on. A few furnaces will operate 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 during a heating or cooling cycle and shut it off after the cycle is over.

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

Advantages to switching to the Fan/On setting:

  • You can keep the temperature throughout your home more uniform by allowing the fan to keep circulating air.
  • Indoor air quality should improve because steady airflow will keep forcing airborne contaminants through the air filter.
  • Fewer start-stop cycles for the HVAC fan helps lengthen its life span. As the air handler is usually a component of the furnace, this means you might prevent the need for furnace repair.

Disadvantages to switching to the Fan/On setting:

  • A constant fan could add to your energy bills somewhat.
  • Nonstop airflow may clog your air filter in a shorter amount of time, increasing the frequency you’ll need to replace it.

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

Through the summer, warm air can persist in unfinished spaces including the attic or an attached garage. If you leave the fan on, your HVAC system may pull this warm air into the rest of your home, forcing the HVAC system to run longer to preserve the desired temperature. In severe heat, this can lead to needing AC repair more often as wear and tear gets worse.

The reverse can happen in the winter. Cooler spaces such as a basement will hold onto cooler air, which may eventually flow into the rest of your home. Leaving the fan running may pump more cold air upward, increasing the amount of heating you need to stay warm.

If you’re still trying to figure out if you should try the fan/on setting, don’t forget that every home and family’s comfort needs will vary. Leaving the HVAC system’s fan on may be best for you if:

Someone in your household has allergies. Allergies and similar respiratory conditions can be stressful on the family. Leaving the fan on should help to enhance indoor air quality, helping your family breathe easier.

Your home deals with hot and cold spots. Lots of homes deal with stubborn hot and cold spots that quickly evolve to a temperature different from the rest of the house. The fan setting should help minimize these changes by constantly refreshing each room’s airflow.