Once the weather is cooling off, you may be wondering about how you’ll take full advantage of your heating and cooling. After all, HVAC costs frequently add up to a big portion of your monthly electric bill. To figure out new ways to save, some owners look closer at their thermostat. Could there be a setting they can 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 will the fan setting provide for your HVAC system? This guide will help. We’ll walk through what exactly the fan setting is and when you can use it to cut costs in the summer or winter.

How Do I Access the Fan Setting on My Thermostat?

For the bulk of thermostats, the fan setting signifies that the HVAC blower fan stays on. A few furnaces will operate at a low level in this setting, but in most cases heating or cooling isn’t being made. The ‘Auto’ setting, on the other hand, will turn on the fan through a heating or cooling cycle and shut it off once the cycle is finished.

There are benefits and drawbacks to switching on the fan setting on your thermostat, and whether you do or don’t {will|can|should]] depend on your personal comfort needs.

Advantages to switching to the Fan/On setting:

  • You can keep the temperature in each room more balanced by permitting the fan to keep running.
  • Indoor air quality should improve as constant airflow will keep forcing airborne particles into the air filter.
  • A smaller number of start-stop cycles for the blower fan helps expand its life span. Because the air handler is typically part of the furnace, this means you can avoid needing furnace repair.

Downsides to switching to the Fan/On setting:

  • A nonstop fan could raise your energy bills somewhat.
  • Nonstop airflow could clog your air filter up more quickly, 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 Each Season

During the summer, warm air will sometimes linger in unfinished spaces such as the attic or an attached garage. If you keep the fan running, your HVAC system might pull this warm air into the rest of your home, forcing the HVAC system to run longer to keep up with the set temperature. In extreme heat, this can lead to needing AC repair more quickly as wear and tear gets worse.

The opposite can occur during the winter. Cooler spaces like a basement will hold onto cooler air, which may eventually make its way into the rest of your home. Keeping the fan on may draw more cold air upward, increasing the amount of heating you need to stay warm.

If you’re still trying to decide if you should try 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 ideal for you if:

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

Your home has hot and cold spots. Many homes wrestle with persistent hot and cold spots that quickly evolve to a temperature different from the rest of the house. The fan setting should help limit these changes by constantly refreshing each room’s supply of air.