Once the weather is cooling off, you might be concerned about how you’ll prepare your heating and cooling. After all, HVAC bills routinely make up a significant piece of your monthly electric bill. To learn new ways to save, some owners look closer at their thermostat. Maybe there’s a setting they should use to boost efficiency?

Most thermostats come with a ‘Fan’ or ‘Fan On’ setting. But if the fan is going during a normal cycle, what can the fan setting offer for an HVAC system? This guide should help. We’ll review just what the fan setting is and whether you can use it to cut costs in the summer or winter.

Should I Use My Thermostat’s Fan Setting?

For the majority of thermostats, the fan setting indicates that the HVAC blower fan stays on. Certain furnaces can 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 run the fan during a heating or cooling cycle and turn it off when the cycle is finished.

There are benefits and drawbacks to switching on the fan setting on your thermostat, and the ideal option {will|can|should]] depend on your unique comfort requirements.

Advantages to trying the Fan/On setting:

  • You can keep the temperature in each room more consistent by permitting the fan to keep generating airflow.
  • Indoor air quality should improve because steady airflow will keep moving airborne pollutants through the air filter.
  • A smaller number of start-stop cycles for the system’s fan helps extend its life span. Because the air handler is often connected to the furnace, this means you might avoid needing furnace repair.

Disadvantages to using the Fan/On setting:

  • A constant fan can raise your energy costs slightly.
  • Nonstop airflow could clog your air filter up more quickly, increasing the frequency you should replace it.

{Choosing Between|Should My Thermostat Be on|Which Setting for My Thermostat? Fan or Auto in Each Season

Through the summer, warm air may stick around in unfinished spaces such as the attic or an attached garage. If you use the fan setting, your HVAC system may gradually move this warm air into the rest of your home, pushing the HVAC system to run longer to maintain the set temperature. In serious heat, this could result in needing AC repair more often as wear and tear gets worse.

The opposite can occur over the winter. Cooler spaces such as a basement will hold onto cooler air, which may eventually make its way into the rest of your home. Leaving the fan setting on may pump more cold air upward, increasing the amount of heating you need to remain warm.

If you’re still trying to figure out if you should switch to the fan/on setting, don’t forget that every home and family’s comfort needs are different. Leaving the HVAC system’s fan on could be best 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 increase indoor air quality, helping your family breathe easier.

Your home has hot and cold spots. Many homes wrestle with persistent 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 steadily refreshing each room’s airflow.