As the weather is cooling off, you are probably thinking about how you’ll prepare your heating and cooling. After all, HVAC expenses frequently contribute a significant chunk of your monthly electric bill. To figure out new ways to reduce costs, some homeowners take a closer look at their thermostat. Maybe there’s a setting they can use to increase efficiency?

The majority of thermostats include both a ‘Fan’ or ‘Fan On’ setting. But if the fan is going during a normal cycle, what can the fan setting provide for your HVAC system? This guide will help. We’ll share what exactly the fan setting is and whether you can use it to save money during the summer or winter.

My Thermostat Has a Fan Setting?

For the majority of thermostats, the fan setting indicates that the system’s blower fan stays on. A few furnaces may continue to operate at a low level with this setting, but for the most part heating or cooling isn’t being made. The ‘Auto’ setting, in contrast, will start the fan through a heating or cooling cycle and shut it off once the cycle is finished.

There are benefits and drawbacks to trying the fan setting on your thermostat, and whether you do or don’t {will|can|should]] depend on your unique comfort requirements.

Advantages to using the Fan/On setting:

  • You can keep the temperature in every room more consistent by allowing the fan to keep generating airflow.
  • Indoor air quality will be highest since continuous airflow will keep forcing airborne particles into the air filter.
  • A smaller amount of start-stop cycles for the HVAC fan helps lengthen its life span. Since the air handler is usually a component of the furnace, this means you could avoid needing furnace repair.

Disadvantages to switching to the Fan/On setting:

  • A continuous fan could increase your energy bills somewhat.
  • Constant airflow may clog your air filter soon, 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

During the summer, warm air can stick around in unfinished spaces including the attic or an attached garage. If you keep the fan running, your HVAC system might draw this warm air into the rest of your home, forcing the HVAC system to work more to maintain the set temperature. In serious heat, this could result in needing AC repair more regularly as wear and tear increases.

The opposite can happen over the winter. Cooler spaces such as a basement will hold onto cooler air, which may eventually flow into the rest of your home. Leaving the fan running will sometimes pump more cold air upward, increasing the amount of heating you need to keep warm.

If you’re still trying to determine if you should switch to the fan/on setting, keep in mind that every home and family’s comfort needs are not the same. Leaving the HVAC system’s fan on may work for you if:

Someone in your household has allergies. Allergies and similar respiratory conditions can be stressful on the family. Leaving the fan on is more likely to improve indoor air quality, helping your family breathe easier.

Your home experiences hot and cold spots. Lots of homes deal with persistent hot and cold spots that quickly return to a temperature different from the rest of the house. The fan setting should help lessen these changes by consistently refreshing each room’s supply of air.