When the weather begins to cool off, you might be wondering about how you’ll make the most of your heating and cooling. After all, HVAC costs can make up a significant piece of your monthly electric bill. To figure out new ways to lower their HVAC bill, some homeowners take a closer look at their thermostat. Could there be a setting they can use to increase 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 provide for your HVAC system? This guide can help. We’ll review what exactly the fan setting is and how you can use it to save money during the summer or winter.

How Do I Access the Fan Setting on My Thermostat?

For the bulk of thermostats, the fan setting indicates that the air handler’s blower fan remains on. Some furnaces can generate heat at a low level in this setting, but in most cases heating or cooling isn’t being made. The ‘Auto’ setting, conversely, will run the fan through a heating or cooling cycle and switch it off once 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 distinct comfort preferences.

Advantages to trying the Fan/On setting:

  • You can keep the temperature throughout your home more balanced by enabling the fan to keep circulating air.
  • Indoor air quality will be highest because steady airflow will keep passing airborne contaminants through the air filter.
  • A smaller amount of 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 might avoid needing furnace repair.

Drawbacks to using the Fan/On setting:

  • A constant fan can raise your energy costs somewhat.
  • Nonstop 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 can linger in unfinished spaces including the attic or an attached garage. If you use the fan setting, your HVAC system can gradually move this warm air into the rest of your home, pushing the HVAC system to work more to keep up with the set temperature. In extreme heat, this could lead to needing AC repair more often as wear and tear increases.

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

If you’re still trying to determine if you should use the fan/on setting, don’t forget that every home and family’s comfort needs will vary. Leaving the HVAC system’s fan on might work for you if:

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

Your home experiences hot and cold spots. Lots of homes wrestle with difficult hot and cold spots that quickly evolve to a temperature different from the rest of the house. The fan setting might help lessen these changes by constantly refreshing each room’s ventilation.