When the weather starts to cool off, you might be thinking about how you’ll make the most of your heating and cooling. After all, HVAC costs frequently make up a big chunk of your monthly electric bill. To try and find ways to save, some homeowners take a closer look at their thermostat. Maybe there’s a setting they can use to improve efficiency?

The bulk of thermostats have a ‘Fan’ or ‘Fan On’ setting. But if the fan is running during a normal cycle, what will the fan setting offer for your HVAC system? This guide should help. We’ll review what exactly the fan setting is and when you can use it to save money over the summer or winter.

What Is the Fan Setting on My Thermostat?

For most thermostats, the fan setting signifies that the system’s blower fan remains on. A few furnaces may continue to run at a low level in this setting, but for the most part heating or cooling isn’t being made. The ‘Auto’ setting, in contrast, will start 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 what’s ideal {will|can|should]] depend on your distinct 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 generating airflow.
  • Indoor air quality will be highest since constant airflow will keep passing airborne particles into the air filter.
  • A smaller number of start-stop cycles for the blower fan helps extend its life span. As the air handler is typically part of the furnace, this means you might minimize the risk of needing furnace repair.

Downsides to using the Fan/On setting:

  • A constant fan could raise your energy costs slightly.
  • Nonstop airflow could clog your air filter soon, 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 Summer/Winter

During the summer, warm air can linger in unfinished spaces including the attic or an attached garage. If you keep the fan running, your HVAC system may draw this warm air into the rest of your home, forcing the HVAC system to work more to keep up with the desired temperature. In serious heat, this can lead to needing AC repair more often as wear and tear grows.

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 will sometimes pump more cold air upward, increasing the amount of heating you need to remain warm.

If you’re still trying to determine if you should switch to the fan/on setting, keep in mind that every home and family’s comfort needs are different. Leaving the HVAC system’s fan on might be ideal for you if:

Someone in your household has allergies. Allergies and similar 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 deals with hot and cold spots. Lots of homes wrestle with stubborn hot and cold spots that quickly evolve to a temperature different from the rest of the house. The fan setting might help minimize these changes by constantly refreshing each room’s airflow.