As the weather is cooling off, you are probably wondering about how you’ll prepare your heating and cooling. After all, HVAC expenses frequently make up a big chunk of your monthly electric bill. To try and find ways to reduce costs, some people look closely at their thermostat. Maybe there’s a setting they should use to increase efficiency?

The bulk 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 offer for an HVAC system? This guide will help. We’ll walk through what exactly the fan setting is and how you can use it to save money in the summer or winter.

My Thermostat Has a Fan Setting?

For the majority of thermostats, the fan setting signifies that the system's blower fan remains on. A few furnaces may continue to generate heat at a low level with this setting, but in general heating or cooling isn’t being generated. The ‘Auto’ setting, on the other hand, will turn on the fan during a heating or cooling cycle and turn it off after the cycle is complete.

There are pros and cons to using the fan setting on your thermostat, and what's ideal {will|can|should]] depend on your distinct comfort preferences.

Advantages to trying the Fan/On setting:

  • You can keep the temperature in each room more balanced by permitting the fan to keep running.
  • Indoor air quality can increase because steady airflow will keep moving airborne particles through the air filter.
  • A smaller number of start-stop cycles for the HVAC fan helps expand its life span. As the air handler is usually a component of the furnace, this means you could prevent the need for furnace repair.

Downsides to utilizing the Fan/On setting:

  • A continuous fan could increase your energy expenses by a small margin.
  • Continuous airflow may 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 Each Season

During the summer, warm air will sometimes persist in unfinished spaces such as the attic or an attached garage. If you leave the fan on, your HVAC system can gradually move this warm air into the rest of your home, compelling the HVAC system to run longer to maintain the preferred temperature. In serious heat, this may result in needing AC repair more quickly as wear and tear gets worse.

The opposite can occur during the winter. Cooler spaces such as a basement will hold onto cooler air, which may eventually flow into the rest of your home. Keeping the fan on could pull more cold air upward, increasing the amount of heating you need to remain warm.

If you’re still trying to determine if you should try the fan/on setting, don’t forget that every home and family’s comfort needs are not the same. Leaving the HVAC system’s fan on could be best for you if:

Someone in your household suffers from 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 persistent hot and cold spots that quickly return to a temperature different from the rest of the house. The fan setting might help limit these changes by consistently refreshing each room’s airflow.