As the weather starts to cool off, you might be thinking about how you’ll make the most of your heating and cooling. After all, HVAC expenses routinely make up a large chunk of your monthly electric bill. To try and find ways to reduce costs, some owners look closer at their thermostat. Could there be a setting they should use to boost efficiency?

Most thermostats include both a ‘Fan’ or ‘Fan On’ setting. But if the fan is on during a typical cycle, what can the fan setting offer for your HVAC system? This guide can help. We’ll review precisely what the fan setting is and when you can use it to reduce costs in the summer or winter.

What Is the Fan Setting on My Thermostat?

For most thermostats, the fan setting signifies that the HVAC blower fan keeps running. A few furnaces will operate at a low level in 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 turn it off when the cycle is finished.

There are benefits and drawbacks to trying the fan setting on your thermostat, and whether you do or don’t {will|can|should]] depend on your personal 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 generating airflow.
  • Indoor air quality can increase because continuous airflow will keep moving airborne pollutants into the air filter.
  • Fewer start-stop cycles for the HVAC fan helps lengthen its life span. Because the air handler is typically part of the furnace, this means you could minimize the risk of needing furnace repair.

Disadvantages to switching to the Fan/On setting:

  • A constant fan will likely raise your energy bills by a small margin.
  • Constant airflow can clog your air filter soon, increasing the frequency you’ll need to replace it.

Should My Thermostat Be on Fan or Auto in Summer/Winter

In the summer, warm air can linger in unfinished spaces like the attic or an attached garage. If you leave the fan on, your HVAC system might pull this warm air into the rest of your home, forcing the HVAC system to work more to maintain the desired temperature. In severe heat, this can result in needing AC repair more quickly as wear and tear increases.

The reverse can take place in the winter. Cooler spaces such as a basement will hold onto cooler air, which will eventually flow into the rest of your home. Leaving the fan running will sometimes pull more cold air upward, increasing the amount of heating you need to remain warm.

If you’re still trying to determine if you should switch to the fan/on setting, keep in mind that every home and family’s comfort needs will vary. Leaving the HVAC system’s fan on might work for you if:

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

Your home has hot and cold spots. Lots of homes wrestle with stubborn hot and cold spots that quickly return to a temperature different from the rest of the house. The fan setting can help minimize these changes by constantly refreshing each room’s airflow.