As the weather is cooling off, you might be thinking about how you’ll prepare your heating and cooling. After all, HVAC costs can add up to a large piece of your monthly electric bill. To try and find ways to reduce costs, some owners look closely at their thermostat. Is there a setting they should use to boost efficiency?

The majority of thermostats come with a ‘Fan’ or ‘Fan On’ setting. But if the fan is on during a typical cycle, what does the fan setting provide for an HVAC system? This guide will help. We’ll share just what the fan setting is and how 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 air handler’s blower fan keeps running. A few furnaces can run at a low level in this setting, but in most cases heating or cooling isn’t being generated. The ‘Auto’ setting, in contrast, will start the fan during a heating or cooling cycle and switch it off when the cycle is finished.

There are pros and cons to switching on the fan setting on your thermostat, and the ideal option {will|can|should]] depend on your unique comfort preferences.

Advantages to using the Fan/On setting:

  • You can keep the temperature in every room more uniform by allowing the fan to keep circulating air.
  • Indoor air quality should improve since continuous airflow will keep forcing airborne pollutants into the air filter.
  • A smaller amount of start-stop cycles for the HVAC fan helps lengthen its life span. Because the air handler is usually part of the furnace, this means you might minimize the risk of needing furnace repair.

Downsides to utilizing the Fan/On setting:

  • A continuous fan can raise your energy expenses somewhat.
  • Constant airflow can clog your air filter in a shorter amount of time, increasing the frequency you’ll need 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 can persist in unfinished spaces such as the attic or an attached garage. If you keep the fan running, your HVAC system may draw this warm air into the rest of your home, pushing the HVAC system to run longer to keep up with the desired temperature. In serious heat, this can lead to needing AC repair more often as wear and tear gets worse.

The reverse can occur during the winter. Cooler spaces like a basement will hold onto cooler air, which may eventually flow into the rest of your home. Leaving the fan running 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 switch to 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 has allergies. Allergies and other respiratory conditions can be hard on the family. Leaving the fan on should help to increase indoor air quality, helping your family breathe easier.

Your home has hot and cold spots. All kinds of homes deal with stubborn hot and cold spots that quickly shift to a temperature different from the rest of the house. The fan setting might help minimize these changes by constantly refreshing each room’s supply of air.