When the weather begins to cool off, you may be concerned about how you’ll prepare your heating and cooling. After all, HVAC expenses routinely contribute a significant chunk of your monthly electric bill. To learn new ways to reduce costs, some people look closer at their thermostat. Maybe there’s a setting they can use to boost efficiency?

The bulk of thermostats include both a ‘Fan’ or ‘Fan On’ setting. But if the fan is on during a typical cycle, what does the fan setting provide for your HVAC system? This guide should help. We’ll walk through precisely what the fan setting is and how you can use it to reduce costs in the summer or winter.

Should I Use My Thermostat’s Fan Setting?

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

There are benefits and drawbacks to trying the fan setting on your thermostat, and the ideal option {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 balanced by allowing the fan to keep running.
  • Indoor air quality can increase since continuous airflow will keep moving airborne pollutants through the air filter.
  • Fewer start-stop cycles for the system’s fan helps expand its life span. Since the air handler is typically a component of the furnace, this means you could avoid needing furnace repair.

Disadvantages to using the Fan/On setting:

  • A constant fan will likely increase your energy costs slightly.
  • Constant airflow can 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 Each Season

In the summer, warm air can linger in unfinished spaces like the attic or an attached garage. If you keep the fan running, your HVAC system might pull this warm air into the rest of your home, compelling the HVAC system to run longer to maintain the desired temperature. In severe heat, this could result in needing AC repair more quickly as wear and tear grows.

The opposite can happen over the winter. Cooler spaces like a basement will hold onto cooler air, which can eventually make its way into the rest of your home. Keeping the fan on may pump more cold air upward, increasing the amount of heating you need to stay warm.

If you’re still trying to decide if you should try the fan/on setting, don’t forget that every home and family’s comfort needs are different. Leaving the HVAC system’s fan on may be ideal for you if:

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

Your home experiences 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 might help limit these changes by steadily refreshing each room’s supply of air.