As the weather starts to cool off, you may be concerned about how you’ll prepare your heating and cooling. After all, HVAC bills can add up to a large portion of your monthly electric bill. To learn new ways to lower their HVAC bill, some owners take a closer look at their thermostat. Is there a setting they can use to improve efficiency?

The majority of thermostats come with a ‘Fan’ or ‘Fan On’ setting. But if the fan is going during a typical cycle, what will the fan setting offer for the HVAC system? This guide can help. We’ll walk through what exactly the fan setting is and how you can use it to reduce costs over the summer or winter.

What Is the Fan Setting on My Thermostat?

For the bulk of thermostats, the fan setting indicates that the HVAC blower fan remains on. Certain furnaces will run 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 over a heating or cooling cycle and turn it off after the cycle is over.

There are advantages and disadvantages to trying the fan setting on your thermostat, and the ideal option {will|can|should]] depend on your personal comfort requirements.

Advantages to switching to the Fan/On setting:

  • You can keep the temperature in every room more uniform by allowing the fan to keep circulating air.
  • Indoor air quality can increase since steady airflow will keep moving airborne particles into the air filter.
  • A smaller amount of start-stop cycles for the blower fan helps lengthen its life span. Since the air handler is often connected to the furnace, this means you could avoid needing furnace repair.

Drawbacks to switching to the Fan/On setting:

  • A nonstop fan can increase your energy expenses somewhat.
  • Continuous airflow can 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

In the summer, warm air will sometimes stick around in unfinished spaces such as the attic or an attached garage. If you keep the fan running, your HVAC system may pull this warm air into the rest of your home, pushing the HVAC system to work harder to keep up with the preferred temperature. In severe heat, this could lead to needing AC repair more often as wear and tear grows.

The reverse can take place during the winter. Cooler spaces such as a basement will hold onto cooler air, which can eventually drift into the rest of your home. Keeping the fan on may pump more cold air upward, increasing the amount of heating you need to remain warm.

If you’re still trying to decide 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 be ideal for you if:

Someone in your household suffers from allergies. Allergies and other respiratory conditions can be tough on the family. Leaving the fan on should help to improve indoor air quality, helping your family breathe easier.

Your home experiences hot and cold spots. Lots of 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 airflow.