As the weather starts to cool off, you are probably wondering about how you’ll make the most of your heating and cooling. After all, HVAC bills can make up a large portion of your monthly electric bill. To try and find ways to save, some homeowners look closer at their thermostat. Is there a setting they can use to increase efficiency?

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

What Is the Fan Setting on My Thermostat?

For the majority of thermostats, the fan setting signifies that the system's blower fan keeps running. Certain furnaces can generate heat at a low level in this setting, but for the most part heating or cooling isn’t being made. The ‘Auto’ setting, on the other hand, will turn on the fan during a heating or cooling cycle and switch it off when the cycle is over.

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

Advantages to utilizing the Fan/On setting:

  • You can keep the temperature throughout your home more consistent by enabling the fan to keep running.
  • Indoor air quality should improve since continuous airflow will keep forcing airborne contaminants 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 often connected to the furnace, this means you could minimize the risk of needing furnace repair.

Downsides to utilizing the Fan/On setting:

  • A constant fan could add to your energy costs 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

During the summer, warm air will sometimes linger in unfinished spaces such as the attic or an attached garage. If you leave the fan on, your HVAC system may draw this warm air into the rest of your home, forcing the HVAC system to work harder to maintain the desired temperature. In severe heat, this could lead to needing AC repair more often as wear and tear gets worse.

The opposite can occur in the winter. Cooler spaces like a basement will hold onto cooler air, which can eventually flow 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 decide if you should switch to 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 ideal for you if:

Someone in your household deals with allergies. Allergies and similar respiratory conditions can be stressful 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. Lots of homes wrestle with stubborn hot and cold spots that quickly shift to a temperature different from the rest of the house. The fan setting can help minimize these changes by constantly refreshing each room’s airflow.