Once the weather begins to cool off, you may be wondering about how you’ll prepare your heating and cooling. After all, HVAC expenses routinely contribute a large piece of your monthly electric bill. To figure out new ways to reduce costs, some people take a closer look 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 running during a typical cycle, what can the fan setting offer for an HVAC system? This guide will help. We’ll walk through what exactly the fan setting is and whether 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 means that the system's blower fan keeps running. A few furnaces can operate at a low level in this setting, but in most cases heating or cooling isn’t being generated. The ‘Auto’ setting, on the other hand, will start the fan over a heating or cooling cycle and shut it off after the cycle is over.

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

Advantages to trying the Fan/On setting:

  • You can keep the temperature throughout your home more balanced by allowing the fan to keep generating airflow.
  • Indoor air quality will be highest since continuous airflow will keep moving airborne contaminants through the air filter.
  • A smaller number of start-stop cycles for the system's fan helps expand its life span. Since the air handler is often connected to the furnace, this means you can minimize the risk of needing furnace repair.

Drawbacks to utilizing the Fan/On setting:

  • A nonstop fan could add to your energy bills slightly.
  • Nonstop 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

In the summer, warm air may linger in unfinished spaces such as the attic or an attached garage. If you keep the fan running, your HVAC system may pull this warm air into the rest of your home, forcing the HVAC system to work harder to keep up with the desired temperature. In serious heat, this may result in needing AC repair more often as wear and tear gets worse.

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

If you’re still trying to figure out if you should switch to the fan/on setting, don’t forget that every home and family’s comfort needs will vary. Leaving the HVAC system’s fan on could be ideal for you if:

Someone in your household has allergies. Allergies and other respiratory conditions can be hard on the family. Leaving the fan on should help to enhance indoor air quality, helping your family breathe easier.

Your home deals with hot and cold spots. Lots of homes deal with difficult hot and cold spots that quickly return to a temperature different from the rest of the house. The fan setting might help minimize these changes by steadily refreshing each room’s supply of air.