When the weather starts to cool off, you are probably concerned about how you’ll prepare your heating and cooling. After all, HVAC expenses routinely make up a large chunk of your monthly electric bill. To figure out new ways to lower their HVAC bill, some owners look closely at their thermostat. Maybe there’s a setting they could use to increase efficiency?

Most thermostats have a ‘Fan’ or ‘Fan On’ setting. But if the fan is on during a regular cycle, what does the fan setting provide for an HVAC system? This guide can help. We’ll share precisely what the fan setting is and when you can use it to reduce costs during the summer or winter.

Should I Use My Thermostat’s Fan Setting?

For the majority of thermostats, the fan setting indicates that the system’s blower fan keeps running. Certain furnaces can operate at a low level with this setting, but in general heating or cooling isn’t being generated. The ‘Auto’ setting, in contrast, will turn on the fan over a heating or cooling cycle and shut it off when the cycle is complete.

There are benefits and drawbacks to using the fan setting on your thermostat, and what’s ideal {will|can|should]] depend on your unique comfort needs.

Advantages to trying the Fan/On setting:

  • You can keep the temperature in every room more balanced by allowing the fan to keep generating airflow.
  • Indoor air quality can increase since continuous airflow will keep passing airborne particles into the air filter.
  • A smaller amount of start-stop cycles for the HVAC fan helps expand its life span. As the air handler is often a component of the furnace, this means you could minimize the risk of needing furnace repair.

Downsides to switching to the Fan/On setting:

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

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

Through the summer, warm air can stick around in unfinished spaces such as the attic or an attached garage. If you leave the fan on, your HVAC system may gradually move this warm air into the rest of your home, pushing the HVAC system to run longer to keep up with the desired temperature. In severe heat, this may lead to needing AC repair more quickly as wear and tear gets worse.

The reverse can occur in the winter. Cooler spaces like a basement will hold onto cooler air, which will eventually drift into the rest of your home. Keeping the fan on will sometimes 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 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 should help to enhance indoor air quality, helping your family breathe easier.

Your home deals with hot and cold spots. Many homes deal with persistent 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.