As the weather begins to cool off, you may be thinking about how you’ll take full advantage of your heating and cooling. After all, HVAC bills frequently make up a large portion of your monthly electric bill. To learn new ways to lower their HVAC bill, some people look closer at their thermostat. Could there be a setting they could use to boost efficiency?

The majority of thermostats include both a ‘Fan’ or ‘Fan On’ setting. But if the fan is going during a normal cycle, what does the fan setting offer for your HVAC system? This guide can help. We’ll share just what the fan setting is and whether you can use it to reduce costs during the summer or winter.

How Do I Access the Fan Setting on My Thermostat?

For the bulk of thermostats, the fan setting indicates that the air handler’s blower fan remains on. Certain furnaces can run at a low level with this setting, but in most cases heating or cooling isn’t being produced. The ‘Auto’ setting, conversely, will run the fan through a heating or cooling cycle and turn it off after the cycle is over.

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

Advantages to switching to the Fan/On setting:

  • You can keep the temperature in each room more uniform by permitting the fan to keep running.
  • Indoor air quality should improve as continuous airflow will keep passing airborne particles into the air filter.
  • Fewer start-stop cycles for the HVAC fan helps lengthen its life span. Because the air handler is usually part of the furnace, this means you can avoid needing furnace repair.

Disadvantages to using the Fan/On setting:

  • A nonstop fan will likely raise your energy expenses by a small margin.
  • Continuous 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

In the summer, warm air can persist in unfinished spaces like the attic or an attached garage. If you keep the fan running, your HVAC system can draw this warm air into the rest of your home, pushing the HVAC system to work more to maintain the set temperature. In severe heat, this could result in needing AC repair more often as wear and tear gets worse.

The opposite can occur in the winter. Cooler spaces such as a basement will hold onto cooler air, which will 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 keep 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 are not the same. Leaving the HVAC system’s fan on might be ideal for you if:

Someone in your household deals with allergies. Allergies and similar respiratory conditions can be tough 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. All kinds of homes wrestle with difficult hot and cold spots that quickly shift to a temperature different from the rest of the house. The fan setting should help lessen these changes by constantly refreshing each room’s ventilation.