When the weather starts to cool off, you are probably concerned about how you’ll prepare your heating and cooling. After all, HVAC bills frequently add up to a big chunk of your monthly electric bill. To try and find ways to reduce costs, some owners look closer at their thermostat. Maybe there’s a setting they can use to improve efficiency?

Most thermostats include both a ‘Fan’ or ‘Fan On’ setting. But if the fan is on during a regular cycle, what will the fan setting provide for an HVAC system? This guide should help. We’ll share precisely what the fan setting is and when you can use it to save money over the summer or winter.

What Is the Fan Setting on My Thermostat?

For most thermostats, the fan setting signifies that the system’s blower fan stays on. A few furnaces can operate at a low level in this setting, but for the most part heating or cooling isn’t being generated. The ‘Auto’ setting, on the other hand, will turn on the fan over a heating or cooling cycle and switch it off once the cycle is finished.

There are advantages and disadvantages to switching on the fan setting on your thermostat, and the ideal option {will|can|should]] depend on your unique 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 generating airflow.
  • Indoor air quality should improve as constant airflow will keep forcing airborne contaminants through the air filter.
  • A smaller number of start-stop cycles for the system’s fan helps expand its life span. Since the air handler is typically a component of the furnace, this means you can prevent the need for furnace repair.

Drawbacks to using the Fan/On setting:

  • A continuous fan could add to your energy bills somewhat.
  • Constant airflow can clog your air filter soon, increasing the frequency you should replace it.

Should My Thermostat Be on? Fan or Auto in Each Season

Through the summer, warm air will sometimes persist in unfinished spaces like the attic or an attached garage. If you leave the fan on, your HVAC system can gradually move this warm air into the rest of your home, forcing the HVAC system to run longer to preserve the preferred temperature. In extreme heat, this can lead to needing AC repair more quickly as wear and tear gets worse.

The reverse can take place over the winter. Cooler spaces like a basement will hold onto cooler air, which may eventually drift into the rest of your home. Leaving the fan setting on could pump more cold air upward, increasing the amount of heating you need to remain 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 are different. Leaving the HVAC system’s fan on might be ideal for you if:

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

Your home deals with hot and cold spots. Lots 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 might help limit these changes by consistently refreshing each room’s airflow.