As the weather starts to cool off, you are probably thinking about how you’ll prepare your heating and cooling. After all, HVAC costs routinely contribute a big portion of your monthly electric bill. To learn new ways to lower their HVAC bill, some owners take a closer look at their thermostat. Maybe there’s a setting they can use to improve efficiency?

The bulk of thermostats include both a ‘Fan’ or ‘Fan On’ setting. But if the fan is running during a regular cycle, what can the fan setting provide for the HVAC system? This guide will help. We’ll walk through just what the fan setting is and how you can use it to save money in the summer or winter.

What Is the Fan Setting on My Thermostat?

For the majority of thermostats, the fan setting indicates that the system’s blower fan keeps running. Some furnaces will operate at a low level with this setting, but in most cases heating or cooling isn’t being made. The ‘Auto’ setting, on the other hand, will run the fan through a heating or cooling cycle and turn it off when the cycle is over.

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

Advantages to trying the Fan/On setting:

  • You can keep the temperature in each room more consistent by allowing the fan to keep running.
  • Indoor air quality should improve as constant airflow will keep forcing airborne pollutants through the air filter.
  • Fewer start-stop cycles for the blower fan helps expand its life span. Because the air handler is usually 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 will likely add to your energy bills slightly.
  • Constant airflow can clog your air filter soon, increasing the frequency you will want to replace it.

{Choosing Between|Should My Thermostat Be on|Which Setting for My Thermostat? Fan or Auto in Summer/Winter

In the summer, warm air may linger in unfinished spaces like the attic or an attached garage. If you use the fan setting, your HVAC system can gradually move this warm air into the rest of your home, forcing the HVAC system to work more to maintain the preferred temperature. In severe heat, this can result in needing AC repair more often as wear and tear increases.

The reverse can occur over the winter. Cooler spaces such as a basement will hold onto cooler air, which may eventually flow into the rest of your home. Leaving the fan setting on could draw more cold air upward, increasing the amount of heating you need to keep 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 different. Leaving the HVAC system’s fan on might work for you if:

Someone in your household deals with allergies. Allergies and other respiratory conditions can be tough 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. Many homes deal with stubborn hot and cold spots that quickly evolve to a temperature different from the rest of the house. The fan setting should help minimize these changes by consistently refreshing each room’s ventilation.