When the weather is cooling off, you may be thinking about how you’ll take full advantage of your heating and cooling. After all, HVAC expenses can make up a significant portion of your monthly electric bill. To try and find ways to lower their HVAC bill, some homeowners look closely at their thermostat. Is there a setting they could use to improve efficiency?

The bulk of thermostats have a ‘Fan’ or ‘Fan On’ setting. But if the fan is running during a normal cycle, what will the fan setting provide for your HVAC system? This guide can help. We’ll walk through precisely what the fan setting is and how you can use it to cut costs during the summer or winter.

Should I Use My Thermostat’s Fan Setting?

For the majority of thermostats, the fan setting means that the system’s blower fan remains on. Some furnaces will operate at a low level with this setting, but for the most part heating or cooling isn’t being produced. The ‘Auto’ setting, in contrast, will turn on the fan during a heating or cooling cycle and shut it off once the cycle is finished.

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

Advantages to using the Fan/On setting:

  • You can keep the temperature throughout your home more uniform by permitting the fan to keep generating airflow.
  • Indoor air quality should improve because constant airflow will keep forcing airborne contaminants through the air filter.
  • Fewer start-stop cycles for the HVAC fan helps lengthen its life span. Because the air handler is usually a component of the furnace, this means you can avoid needing furnace repair.

Disadvantages to utilizing the Fan/On setting:

  • A constant fan can increase your energy costs by a small margin.
  • Constant airflow could clog your air filter soon, increasing the frequency you should replace it.

{Choosing Between|Should My Thermostat Be on|Which Setting for My Thermostat? Fan or Auto in Summer/Winter

During the summer, warm air can linger in unfinished spaces like 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 harder to keep up with the set temperature. In extreme heat, this may lead to needing AC repair more regularly as wear and tear grows.

The opposite can happen in the winter. Cooler spaces such as a basement will hold onto cooler air, which will eventually make its way 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 keep warm.

If you’re still trying to figure out if you should try the fan/on setting, don’t forget that every home and family’s comfort needs are not the same. Leaving the HVAC system’s fan on might be best for you if:

Someone in your household deals with allergies. Allergies and other respiratory conditions can be hard on the family. Leaving the fan on is more likely to enhance indoor air quality, helping your family breathe easier.

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