When the weather starts to cool off, you may be concerned about how you’ll make the most of your heating and cooling. After all, HVAC costs can make up a big portion of your monthly electric bill. To figure out new ways to reduce costs, some people look closely at their thermostat. Maybe there’s a setting they could use to improve efficiency?

The bulk of thermostats have a ‘Fan’ or ‘Fan On’ setting. But if the fan is on during a typical cycle, what will the fan setting offer for the HVAC system? This guide can help. We’ll review what exactly the fan setting is and when you can use it to cut costs during the summer or winter.

What Is the Fan Setting on My Thermostat?

For most thermostats, the fan setting indicates that the system’s blower fan remains on. Some furnaces may continue to operate at a low level with this setting, but in general heating or cooling isn’t being made. The ‘Auto’ setting, on the other hand, will run the fan during a heating or cooling cycle and switch it off after the cycle is finished.

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

Advantages to utilizing the Fan/On setting:

  • You can keep the temperature in each room more consistent by allowing the fan to keep circulating air.
  • Indoor air quality can increase as steady airflow will keep forcing airborne pollutants into the air filter.
  • A smaller number of start-stop cycles for the blower fan helps lengthen its life span. As the air handler is often part of the furnace, this means you might prevent the need for furnace repair.

Disadvantages to utilizing the Fan/On setting:

  • A constant fan could increase your energy bills by a small margin.
  • Continuous airflow may clog your air filter in a shorter amount of time, increasing the frequency you’ll need to replace it.

Which Setting for My Thermostat? Fan or Auto in Each Season

During the summer, warm air may persist in unfinished spaces such as the attic or an attached garage. If you leave the fan on, your HVAC system might draw this warm air into the rest of your home, pushing the HVAC system to work more to maintain the preferred temperature. In extreme heat, this may lead to needing AC repair more quickly as wear and tear increases.

The opposite can occur during the winter. Cooler spaces such as a basement will hold onto cooler air, which will eventually drift into the rest of your home. Keeping the fan on could pull more cold air upward, increasing the amount of heating you need to keep warm.

If you’re still trying to decide if you should use the fan/on setting, don’t forget that every home and family’s comfort needs will vary. Leaving the HVAC system’s fan on might 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 can help to improve indoor air quality, helping your family breathe easier.

Your home deals with hot and cold spots. All kinds 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 can help minimize these changes by steadily refreshing each room’s airflow.