As the weather begins to cool off, you are probably concerned about how you’ll take full advantage of your heating and cooling. After all, HVAC bills frequently add up to a large piece of your monthly electric bill. To figure out new ways to lower their HVAC bill, some people take a closer look at their thermostat. Maybe there’s a setting they can use to boost efficiency?

The bulk of thermostats include both a ‘Fan’ or ‘Fan On’ setting. But if the fan is on during a regular cycle, what can the fan setting offer for the HVAC system? This guide will help. We’ll review precisely what the fan setting is and when you can use it to cut costs over the summer or winter.

What Is the Fan Setting on My Thermostat?

For the bulk of thermostats, the fan setting indicates that the HVAC blower fan stays on. A few furnaces can run at a low level in this setting, but for the most part heating or cooling isn’t being made. The ‘Auto’ setting, on the other hand, will turn on the fan over a heating or cooling cycle and switch it off after the cycle is over.

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

Advantages to using the Fan/On setting:

  • You can keep the temperature in each room more uniform by enabling the fan to keep generating airflow.
  • Indoor air quality will be highest since continuous airflow will keep forcing airborne pollutants through the air filter.
  • A smaller number of start-stop cycles for the HVAC fan helps extend its life span. Since the air handler is often part of the furnace, this means you could prevent the need for furnace repair.

Downsides to switching to the Fan/On setting:

  • A nonstop fan could increase your energy expenses somewhat.
  • Continuous airflow could clog your air filter soon, increasing the frequency you should replace it.

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

During the summer, warm air will sometimes stick around in unfinished spaces including the attic or an attached garage. If you keep the fan running, your HVAC system can draw this warm air into the rest of your home, compelling the HVAC system to work more to maintain the preferred temperature. In extreme heat, this can lead to needing AC repair more often as wear and tear grows.

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

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

Your home experiences hot and cold spots. All kinds of homes deal with difficult hot and cold spots that quickly shift to a temperature different from the rest of the house. The fan setting can help lessen these changes by consistently refreshing each room’s supply of air.