As the weather is cooling off, you are probably concerned about how you’ll prepare your heating and cooling. After all, HVAC bills can make up a significant chunk of your monthly electric bill. To figure out new ways to save, some owners look closely at their thermostat. Could there be a setting they can use to increase efficiency?

Most thermostats come with a ‘Fan’ or ‘Fan On’ setting. But if the fan is on during a normal cycle, what does the fan setting provide for your HVAC system? This guide can help. We’ll walk through just what the fan setting is and how you can use it to save money over 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 stays on. Some furnaces can generate heat at a low level in this setting, but for the most part heating or cooling isn’t being produced. The ‘Auto’ setting, conversely, will turn on the fan during a heating or cooling cycle and switch it off after the cycle is finished.

There are pros and cons to using the fan setting on your thermostat, and the ideal option {will|can|should]] depend on your unique comfort needs.

Advantages to utilizing the Fan/On setting:

  • You can keep the temperature throughout your home more uniform by permitting the fan to keep circulating air.
  • Indoor air quality can increase as steady airflow will keep moving airborne contaminants into the air filter.
  • A smaller number of start-stop cycles for the blower fan helps expand its life span. As the air handler is typically a component of the furnace, this means you can avoid needing furnace repair.

Downsides to utilizing the Fan/On setting:

  • A continuous fan could raise your energy costs slightly.
  • Continuous airflow can clog your air filter up more quickly, 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

Through the summer, warm air will sometimes stick around in unfinished spaces like 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 harder to keep up with the desired temperature. In serious heat, this may result in needing AC repair more regularly as wear and tear gets worse.

The opposite can happen during the winter. Cooler spaces such as a basement will hold onto cooler air, which may eventually drift into the rest of your home. Keeping the fan on could pump more cold air upward, increasing the amount of heating you need to keep warm.

If you’re still trying to decide if you should try the fan/on setting, remember that every home and family’s comfort needs are not the same. Leaving the HVAC system’s fan on may be best for you if:

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

Your home has hot and cold spots. Many homes wrestle with stubborn hot and cold spots that quickly return to a temperature different from the rest of the house. The fan setting can help lessen these changes by constantly refreshing each room’s airflow.