Once the weather starts to cool off, you might be wondering about how you’ll take full advantage of your heating and cooling. After all, HVAC costs frequently add up to a big chunk of your monthly electric bill. To try and find ways to reduce costs, some people look closely at their thermostat. Could there be a setting they could use to improve efficiency?

The majority of thermostats have a ‘Fan’ or ‘Fan On’ setting. But if the fan is going during a typical cycle, what will the fan setting offer for the HVAC system? This guide can help. We’ll share what exactly the fan setting is and whether you can use it to cut costs during the summer or winter.

What Is the Fan Setting on My Thermostat?

For most thermostats, the fan setting means that the HVAC blower fan stays on. Certain furnaces will run 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 start the fan through a heating or cooling cycle and turn it off once the cycle is over.

There are benefits and drawbacks to using the fan setting on your thermostat, and the ideal option {will|can|should]] depend on your personal comfort needs.

Advantages to trying the Fan/On setting:

  • You can keep the temperature throughout your home more consistent by allowing the fan to keep generating airflow.
  • Indoor air quality will be highest as steady airflow will keep passing airborne pollutants through the air filter.
  • A smaller amount of start-stop cycles for the system's fan helps lengthen its life span. Because the air handler is typically a component of the furnace, this means you might avoid needing furnace repair.

Disadvantages to using the Fan/On setting:

  • A continuous fan will likely raise your energy costs slightly.
  • Continuous airflow can 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

Through the summer, warm air will sometimes stick around in unfinished spaces such as the attic or an attached garage. If you leave the fan on, your HVAC system might draw this warm air into the rest of your home, compelling the HVAC system to work harder to preserve the preferred temperature. In extreme heat, this may result in needing AC repair more often as wear and tear increases.

The opposite can take place during the winter. Cooler spaces such as a basement will hold onto cooler air, which can 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 stay warm.

If you’re still trying to decide if you should try the fan/on setting, don’t forget that every home and family’s comfort needs are different. 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 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 stubborn 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.