Once the weather starts to cool off, you might be wondering about how you’ll take full advantage of your heating and cooling. After all, HVAC bills can make up a significant piece of your monthly electric bill. To try and find ways to reduce costs, some homeowners look closer at their thermostat. Is there a setting they can use to improve 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 offer for the HVAC system? This guide should help. We’ll share just what the fan setting is and whether you can use it to save money during the summer or winter.

What Is the Fan Setting on My Thermostat?

For the bulk of thermostats, the fan setting means that the system's blower fan remains on. Certain furnaces will generate heat at a low level with this setting, but in general 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 when the cycle is over.

There are advantages and disadvantages to switching on the fan setting on your thermostat, and the ideal option {will|can|should]] depend on your unique comfort requirements.

Advantages to switching to the Fan/On setting:

  • You can keep the temperature in each room more balanced by enabling the fan to keep generating airflow.
  • Indoor air quality should improve since constant airflow will keep moving airborne particles through the air filter.
  • A smaller number of start-stop cycles for the system's fan helps expand its life span. Because the air handler is often connected to the furnace, this means you could minimize the risk of needing furnace repair.

Drawbacks to using the Fan/On setting:

  • A constant fan could increase your energy expenses by a small margin.
  • Nonstop airflow can clog your air filter soon, 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 Summer/Winter

Through the summer, warm air may stick around in unfinished spaces like the attic or an attached garage. If you leave the fan on, your HVAC system can gradually move this warm air into the rest of your home, compelling the HVAC system to work harder to maintain the desired temperature. In serious heat, this can lead to needing AC repair more quickly as wear and tear increases.

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 may draw more cold air upward, increasing the amount of heating you need to remain warm.

If you’re still trying to decide if you should use the fan/on setting, keep in mind that every home and family’s comfort needs will vary. Leaving the HVAC system’s fan on could be best for you if:

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

Your home experiences hot and cold spots. Many homes wrestle with difficult hot and cold spots that quickly shift to a temperature different from the rest of the house. The fan setting can help limit these changes by consistently refreshing each room’s ventilation.