When the weather begins to cool off, you are probably wondering about how you’ll take full advantage of your heating and cooling. After all, HVAC costs 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. Is there a setting they could use to increase efficiency?

Most thermostats come with a ‘Fan’ or ‘Fan On’ setting. But if the fan is running during a normal cycle, what will the fan setting offer for an HVAC system? This guide should help. We’ll walk through what exactly the fan setting is and when you can use it to reduce costs over the summer or winter.

What Is the Fan Setting on My Thermostat?

For most thermostats, the fan setting indicates that the air handler’s blower fan keeps running. Certain furnaces will operate at a low level with this setting, but for the most part heating or cooling isn’t being generated. The ‘Auto’ setting, conversely, will run the fan over a heating or cooling cycle and turn it off once the cycle is over.

There are pros and cons to switching on the fan setting on your thermostat, and what’s ideal {will|can|should]] depend on your distinct comfort preferences.

Advantages to utilizing the Fan/On setting:

  • You can keep the temperature in each room more consistent by enabling the fan to keep circulating air.
  • Indoor air quality should improve as steady airflow will keep moving airborne pollutants into the air filter.
  • Fewer start-stop cycles for the HVAC fan helps extend its life span. Because the air handler is typically a component of the furnace, this means you might minimize the risk of needing furnace repair.

Disadvantages to utilizing the Fan/On setting:

  • A continuous fan will likely raise your energy expenses somewhat.
  • Nonstop airflow may clog your air filter in a shorter amount of time, increasing the frequency you’ll need to replace it.

Should My Thermostat Be on? Fan or Auto in Each Season

In the summer, warm air may persist in unfinished spaces such as the attic or an attached garage. If you keep the fan running, your HVAC system may pull this warm air into the rest of your home, pushing the HVAC system to work more to maintain the desired temperature. In extreme heat, this may result in needing AC repair more quickly 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 will eventually flow into the rest of your home. Leaving the fan running will sometimes pump more cold air upward, increasing the amount of heating you need to stay warm.

If you’re still trying to decide if you should use the fan/on setting, remember that every home and family’s comfort needs will vary. Leaving the HVAC system’s fan on might 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 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 stubborn hot and cold spots that quickly evolve to a temperature different from the rest of the house. The fan setting might help minimize these changes by steadily refreshing each room’s supply of air.