Once the weather starts to cool off, you may be wondering about how you’ll make the most of your heating and cooling. After all, HVAC expenses frequently add up to a big piece of your monthly electric bill. To try and find ways to lower their HVAC bill, some people take a closer look at their thermostat. Could there be a setting they could use to improve efficiency?

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

What Is the Fan Setting on My Thermostat?

For the majority of thermostats, the fan setting signifies that the air handler’s blower fan stays on. Some furnaces may continue to operate at a low level with this setting, but for the most part heating or cooling isn’t being made. The ‘Auto’ setting, in contrast, will start the fan through a heating or cooling cycle and switch it off after the cycle is over.

There are benefits and drawbacks to switching on the fan setting on your thermostat, and what’s ideal {will|can|should]] depend on your unique comfort requirements.

Advantages to using the Fan/On setting:

  • You can keep the temperature in every room more uniform by permitting the fan to keep circulating air.
  • Indoor air quality can increase since constant airflow will keep forcing airborne pollutants into the air filter.
  • A smaller amount of start-stop cycles for the HVAC fan helps extend its life span. As the air handler is often a component of the furnace, this means you can avoid needing furnace repair.

Downsides to using the Fan/On setting:

  • A constant fan could add to your energy bills slightly.
  • Continuous airflow can clog your air filter soon, increasing the frequency you should replace it.

Which Setting for My Thermostat? Fan or Auto in Summer/Winter

During the summer, warm air may persist in unfinished spaces such as the attic or an attached garage. If you leave the fan on, your HVAC system might gradually move this warm air into the rest of your home, forcing the HVAC system to work more to preserve the set temperature. In severe heat, this can lead to needing AC repair more regularly as wear and tear grows.

The reverse can happen over the winter. Cooler spaces like a basement will hold onto cooler air, which will eventually make its way into the rest of your home. Leaving the fan setting on may pull more cold air upward, increasing the amount of heating you need to keep warm.

If you’re still trying to determine 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 might be ideal for you if:

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

Your home has hot and cold spots. Many homes deal with difficult hot and cold spots that quickly evolve to a temperature different from the rest of the house. The fan setting can help lessen these changes by steadily refreshing each room’s ventilation.