As the weather starts to cool off, you are probably thinking about how you’ll make the most of your heating and cooling. After all, HVAC bills frequently make up a big chunk of your monthly electric bill. To try and find ways to save, some homeowners take a closer look at their thermostat. Could there be a setting they could use to increase efficiency?

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

What Is the Fan Setting on My Thermostat?

For most thermostats, the fan setting signifies that the system's blower fan keeps running. Some furnaces can operate at a low level in this setting, but in general heating or cooling isn’t being generated. The ‘Auto’ setting, in contrast, will start the fan during a heating or cooling cycle and shut it off after the cycle is finished.

There are benefits and drawbacks to trying the fan setting on your thermostat, and what's ideal {will|can|should]] depend on your personal comfort preferences.

Advantages to trying the Fan/On setting:

  • You can keep the temperature in each room more balanced by permitting the fan to keep running.
  • Indoor air quality should improve since continuous airflow will keep passing airborne pollutants through the air filter.
  • A smaller number of start-stop cycles for the system's fan helps lengthen its life span. Since the air handler is typically a component of the furnace, this means you can avoid needing furnace repair.

Drawbacks to utilizing the Fan/On setting:

  • A nonstop fan could raise your energy bills slightly.
  • Nonstop airflow could clog your air filter up more quickly, increasing the frequency you will want to replace it.

Should My Thermostat Be on Fan or Auto in Summer/Winter

Through the summer, warm air can stick around in unfinished spaces like the attic or an attached garage. If you use the fan setting, your HVAC system might pull this warm air into the rest of your home, forcing the HVAC system to run longer to keep up with the set temperature. In serious heat, this can lead to needing AC repair more regularly as wear and tear increases.

The opposite can happen over the winter. Cooler spaces such as a basement will hold onto cooler air, which can eventually flow into the rest of your home. Leaving the fan setting on could draw 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, keep in mind that every home and family’s comfort needs are not the same. Leaving the HVAC system’s fan on may be ideal for you if:

Someone in your household suffers from allergies. Allergies and similar respiratory conditions can be tough on the family. Leaving the fan on is more likely to enhance indoor air quality, helping your family breathe easier.

Your home deals with hot and cold spots. All kinds of homes wrestle with difficult hot and cold spots that quickly return to a temperature different from the rest of the house. The fan setting might help lessen these changes by consistently refreshing each room’s airflow.