As the weather begins to cool off, you may be wondering about how you’ll prepare your heating and cooling. After all, HVAC bills routinely contribute a big chunk of your monthly electric bill. To learn new ways to lower their HVAC bill, some owners look closer at their thermostat. Maybe there’s a setting they can use to increase efficiency?

The bulk of thermostats include both a ‘Fan’ or ‘Fan On’ setting. But if the fan is on during a regular cycle, what can the fan setting offer for the HVAC system? This guide should help. We’ll review precisely what the fan setting is and whether 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 remains on. A few furnaces will operate at a low level with this setting, but for the most part heating or cooling isn’t being produced. The ‘Auto’ setting, on the other hand, will turn on the fan over a heating or cooling cycle and shut it off after the cycle is complete.

There are benefits and drawbacks to using 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 every room more uniform by enabling the fan to keep running.
  • Indoor air quality can increase as constant airflow will keep moving airborne contaminants into the air filter.
  • A smaller amount of start-stop cycles for the HVAC fan helps extend its life span. As the air handler is often a component of the furnace, this means you might prevent the need for furnace repair.

Downsides to using the Fan/On setting:

  • A constant fan can increase your energy expenses somewhat.
  • Constant airflow may clog your air filter up more quickly, 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 Each Season

Through the summer, warm air will sometimes stick around in unfinished spaces including the attic or an attached garage. If you leave the fan on, your HVAC system may pull this warm air into the rest of your home, pushing the HVAC system to work more to preserve the preferred temperature. In serious heat, this could lead to needing AC repair more often as wear and tear gets worse.

The reverse can occur in the winter. Cooler spaces such as a basement will hold onto cooler air, which may eventually make its way into the rest of your home. Leaving the fan running may pull more cold air upward, increasing the amount of heating you need to stay warm.

If you’re still trying to determine 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 work for you if:

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

Your home deals with hot and cold spots. All kinds of homes wrestle with persistent hot and cold spots that quickly shift to a temperature different from the rest of the house. The fan setting might help limit these changes by constantly refreshing each room’s ventilation.