When 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 expenses routinely add up to a significant piece of your monthly electric bill. To learn new ways to lower their HVAC bill, some homeowners look closely at their thermostat. Is there 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 running 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 save money in the summer or winter.

Should I Use My Thermostat's Fan Setting?

For most thermostats, the fan setting signifies that the air handler’s blower fan stays on. Certain furnaces can run at a low level in this setting, but in most cases heating or cooling isn’t being produced. The ‘Auto’ setting, conversely, will start the fan over a heating or cooling cycle and switch it off once the cycle is over.

There are advantages and disadvantages to using the fan setting on your thermostat, and whether you do or don’t {will|can|should]] depend on your personal comfort requirements.

Advantages to utilizing the Fan/On setting:

  • You can keep the temperature throughout your home more balanced by enabling the fan to keep circulating air.
  • Indoor air quality can increase as continuous airflow will keep passing airborne pollutants into the air filter.
  • A smaller amount of start-stop cycles for the HVAC fan helps extend its life span. Since the air handler is usually part of the furnace, this means you can prevent the need for furnace repair.

Downsides to switching to the Fan/On setting:

  • A nonstop fan will likely raise your energy bills slightly.
  • Constant airflow could clog your air filter in a shorter amount of time, 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 can linger in unfinished spaces like the attic or an attached garage. If you leave the fan on, your HVAC system can draw this warm air into the rest of your home, pushing the HVAC system to work harder to maintain the desired temperature. In severe heat, this may result in needing AC repair more quickly as wear and tear gets worse.

The opposite can happen in the winter. Cooler spaces such as a basement will hold onto cooler air, which will 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 keep warm.

If you’re still trying to determine if you should use the fan/on setting, remember that every home and family’s comfort needs will vary. Leaving the HVAC system’s fan on might be best for you if:

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

Your home deals with hot and cold spots. All kinds of homes deal with stubborn hot and cold spots that quickly evolve to a temperature different from the rest of the house. The fan setting can help minimize these changes by consistently refreshing each room’s airflow.