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

Most thermostats come with a ‘Fan’ or ‘Fan On’ setting. But if the fan is going during a regular cycle, what does the fan setting provide for an HVAC system? This guide can help. We’ll walk through precisely what the fan setting is and how you can use it to reduce costs in the summer or winter.

My Thermostat Has a Fan Setting?

For most thermostats, the fan setting signifies that the system’s blower fan stays on. A few furnaces may continue to generate heat at a low level with this setting, but for the most part heating or cooling isn’t being made. 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 over.

There are pros and cons to using the fan setting on your thermostat, and what’s ideal {will|can|should]] depend on your personal comfort preferences.

Advantages to utilizing the Fan/On setting:

  • You can keep the temperature in every room more balanced by enabling the fan to keep circulating air.
  • Indoor air quality should improve since steady airflow will keep moving airborne contaminants into the air filter.
  • A smaller amount of start-stop cycles for the system’s fan helps expand its life span. Since the air handler is often connected to the furnace, this means you can avoid needing furnace repair.

Downsides to switching to the Fan/On setting:

  • A continuous fan can raise your energy bills somewhat.
  • Constant airflow could clog your air filter in a shorter amount of time, increasing the frequency you should replace it.

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

During the summer, warm air may stick around 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 severe heat, this can lead to needing AC repair more quickly as wear and tear grows.

The reverse can happen during 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. Keeping the fan on may pump more cold air upward, increasing the amount of heating you need to stay warm.

If you’re still trying to figure out if you should try the fan/on setting, remember that every home and family’s comfort needs are not the same. Leaving the HVAC system’s fan on might be best 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 should help to improve 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 evolve to a temperature different from the rest of the house. The fan setting might help minimize these changes by consistently refreshing each room’s ventilation.