Once the weather begins to cool off, you may be concerned about how you’ll take full advantage of your heating and cooling. After all, HVAC bills routinely add up to a big chunk of your monthly electric bill. To try and find ways to reduce costs, some people take a closer look at their thermostat. Could there be 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 on during a regular cycle, what does the fan setting provide for your HVAC system? This guide should help. We’ll share what exactly the fan setting is and whether you can use it to reduce costs in the summer or winter.

How Do I Access the Fan Setting on My Thermostat?

For the majority of thermostats, the fan setting means that the air handler’s blower fan keeps running. A few furnaces can run at a low level with this setting, but in general heating or cooling isn’t being generated. The ‘Auto’ setting, conversely, will turn on the fan over a heating or cooling cycle and shut it off when the cycle is complete.

There are pros and cons to switching on the fan setting on your thermostat, and whether you do or don’t {will|can|should]] depend on your personal comfort requirements.

Advantages to switching to the Fan/On setting:

  • You can keep the temperature throughout your home more uniform by permitting the fan to keep running.
  • Indoor air quality should improve as continuous airflow will keep moving airborne contaminants into the air filter.
  • Fewer start-stop cycles for the system’s fan helps expand its life span. Since the air handler is usually a component of the furnace, this means you might minimize the risk of needing furnace repair.

Disadvantages to using the Fan/On setting:

  • A nonstop fan could increase your energy expenses somewhat.
  • Continuous airflow can clog your air filter soon, 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

During the summer, warm air may persist in unfinished spaces like the attic or an attached garage. If you use the fan setting, your HVAC system can pull this warm air into the rest of your home, compelling the HVAC system to work more to preserve the preferred temperature. In extreme heat, this could result in needing AC repair more quickly as wear and tear grows.

The opposite can happen 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 running could pull more cold air upward, increasing the amount of heating you need to keep warm.

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

Someone in your household deals with allergies. Allergies and similar respiratory conditions can be stressful on the family. Leaving the fan on is more likely to increase indoor air quality, helping your family breathe easier.

Your home experiences hot and cold spots. Lots of homes deal with difficult hot and cold spots that quickly shift to a temperature different from the rest of the house. The fan setting might help lessen these changes by constantly refreshing each room’s ventilation.