When the weather starts to cool off, you are probably concerned about how you’ll take full advantage of your heating and cooling. After all, HVAC expenses can contribute a large piece of your monthly electric bill. To learn new ways to reduce costs, some people look closer at their thermostat. Maybe there’s a setting they could use to increase efficiency?

The majority of thermostats come with a ‘Fan’ or ‘Fan On’ setting. But if the fan is on during a typical cycle, what can the fan setting provide for an HVAC system? This guide can help. We’ll review 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 most thermostats, the fan setting indicates that the air handler’s blower fan stays on. Some furnaces can run at a low level with this setting, but in most cases heating or cooling isn’t being produced. The ‘Auto’ setting, conversely, 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 trying the fan setting on your thermostat, and whether you do or don’t {will|can|should]] depend on your unique comfort preferences.

Advantages to utilizing the Fan/On setting:

  • You can keep the temperature in each room more consistent by enabling the fan to keep circulating air.
  • Indoor air quality can increase since continuous airflow will keep moving airborne particles through the air filter.
  • Fewer start-stop cycles for the blower fan helps expand its life span. As the air handler is usually connected to the furnace, this means you might avoid needing furnace repair.

Disadvantages to utilizing the Fan/On setting:

  • A nonstop fan could add to your energy expenses slightly.
  • Nonstop airflow can clog your air filter up more quickly, increasing the frequency you’ll need to replace it.

Which Setting for My Thermostat? Fan or Auto in Summer/Winter

Through the summer, warm air will sometimes linger in unfinished spaces like 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 work harder to maintain the preferred temperature. In serious heat, this may result in needing AC repair more often as wear and tear increases.

The reverse can take place in the winter. Cooler spaces like a basement will hold onto cooler air, which can eventually flow 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 switch to the fan/on setting, don’t forget that every home and family’s comfort needs will vary. Leaving the HVAC system’s fan on may be best for you if:

Someone in your household suffers from allergies. Allergies and similar respiratory conditions can be hard on the family. Leaving the fan on is more likely to enhance indoor air quality, helping your family breathe easier.

Your home deals with hot and cold spots. Many homes wrestle with difficult hot and cold spots that quickly return to a temperature different from the rest of the house. The fan setting should help lessen these changes by constantly refreshing each room’s airflow.