When the weather is cooling off, you might be thinking about how you’ll prepare your heating and cooling. After all, HVAC bills routinely make up a large piece of your monthly electric bill. To try and find ways to save, some homeowners take a closer look at their thermostat. Is there a setting they can use to improve efficiency?

Most thermostats include both a ‘Fan’ or ‘Fan On’ setting. But if the fan is going during a typical cycle, what can the fan setting offer for your HVAC system? This guide can help. We’ll walk through precisely what the fan setting is and when you can use it to save money over the summer or winter.

My Thermostat Has a Fan Setting?

For the majority of thermostats, the fan setting means that the HVAC blower fan remains on. Some furnaces can run at a low level in this setting, but in general heating or cooling isn’t being generated. The ‘Auto’ setting, on the other hand, will run the fan during a heating or cooling cycle and shut it off once the cycle is finished.

There are pros and cons to switching on the fan setting on your thermostat, and what’s ideal {will|can|should]] depend on your personal comfort requirements.

Advantages to trying the Fan/On setting:

  • You can keep the temperature throughout your home more uniform by permitting the fan to keep circulating air.
  • Indoor air quality will be highest as continuous airflow will keep moving airborne particles into the air filter.
  • A smaller amount of start-stop cycles for the system’s fan helps expand its life span. Because the air handler is typically connected to the furnace, this means you might prevent the need for furnace repair.

Drawbacks to using the Fan/On setting:

  • A continuous fan can increase your energy costs by a small margin.
  • Continuous airflow could 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 can linger in unfinished spaces such as the attic or an attached garage. If you keep the fan running, your HVAC system might pull this warm air into the rest of your home, pushing the HVAC system to work harder to keep up with the set temperature. In extreme heat, this could lead to needing AC repair more regularly as wear and tear grows.

The reverse can take place in the winter. Cooler spaces like a basement will hold onto cooler air, which will eventually drift into the rest of your home. Leaving the fan setting on will sometimes draw more cold air upward, increasing the amount of heating you need to stay warm.

If you’re still trying to determine if you should try the fan/on setting, keep in mind that every home and family’s comfort needs will vary. Leaving the HVAC system’s fan on might work for you if:

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

Your home has hot and cold spots. Many homes wrestle with difficult hot and cold spots that quickly shift to a temperature different from the rest of the house. The fan setting might help limit these changes by constantly refreshing each room’s airflow.