As the weather starts to cool off, you might be concerned about how you’ll make the most of your heating and cooling. After all, HVAC expenses can make up a large chunk of your monthly electric bill. To learn new ways to lower their HVAC bill, some owners take a closer look at their thermostat. Could there be a setting they can use to improve efficiency?

The majority of thermostats come with a ‘Fan’ or ‘Fan On’ setting. But if the fan is going during a typical cycle, what will the fan setting offer for an HVAC system? This guide can help. We’ll review what exactly the fan setting is and when you can use it to reduce costs over the summer or winter.

How Do I Access the Fan Setting on My Thermostat?

For most thermostats, the fan setting indicates that the air handler’s blower fan stays on. Certain furnaces will operate at a low level with this setting, but for the most part heating or cooling isn’t being produced. The ‘Auto’ setting, conversely, will start the fan through a heating or cooling cycle and turn it off when the cycle is finished.

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

Advantages to switching to 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 can increase as constant airflow will keep forcing airborne pollutants into the air filter.
  • A smaller amount of start-stop cycles for the HVAC fan helps extend its life span. Since the air handler is often a component of the furnace, this means you could avoid needing furnace repair.

Drawbacks to switching to the Fan/On setting:

  • A nonstop fan will likely increase your energy expenses somewhat.
  • Constant airflow could 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 Summer/Winter

In the summer, warm air can linger in unfinished spaces including 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, pushing the HVAC system to work more to preserve the preferred temperature. In severe heat, this may result in needing AC repair more quickly as wear and tear increases.

The opposite can take place in the winter. Cooler spaces such as a basement will hold onto cooler air, which will eventually flow into the rest of your home. Leaving the fan setting on may draw 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 will vary. Leaving the HVAC system’s fan on could work for you if:

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

Your home has hot and cold spots. All kinds of homes wrestle with persistent hot and cold spots that quickly evolve to a temperature different from the rest of the house. The fan setting might help limit these changes by consistently refreshing each room’s ventilation.