As the weather is cooling off, you are probably concerned about how you’ll take full advantage of your heating and cooling. After all, HVAC costs routinely contribute a significant chunk of your monthly electric bill. To learn new ways to save, some people look closely at their thermostat. Is there a setting they can use to increase efficiency?

The bulk of thermostats have a ‘Fan’ or ‘Fan On’ setting. But if the fan is running during a regular cycle, what can the fan setting offer for your HVAC system? This guide will help. We’ll review just what the fan setting is and when you can use it to save money over the summer or winter.

My Thermostat Has a Fan Setting?

For most thermostats, the fan setting means that the system’s blower fan stays on. Some furnaces can generate heat at a low level in this setting, but in general heating or cooling isn’t being made. The ‘Auto’ setting, on the other hand, will turn on the fan through a heating or cooling cycle and shut it off when the cycle is over.

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

Advantages to using the Fan/On setting:

  • You can keep the temperature in each room more consistent by allowing the fan to keep running.
  • Indoor air quality can increase as continuous airflow will keep moving airborne contaminants through the air filter.
  • A smaller amount of start-stop cycles for the system’s fan helps extend its life span. Because the air handler is typically connected to the furnace, this means you might minimize the risk of needing furnace repair.

Downsides to switching to the Fan/On setting:

  • A nonstop fan can add to your energy bills slightly.
  • Continuous airflow could clog your air filter in a shorter amount of time, 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

Through the summer, warm air can linger in unfinished spaces including the attic or an attached garage. If you leave the fan on, your HVAC system might draw this warm air into the rest of your home, forcing the HVAC system to work more to preserve the desired temperature. In extreme heat, this could result in needing AC repair more regularly as wear and tear increases.

The reverse can take place in 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 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 switch to the fan/on setting, don’t forget that every home and family’s comfort needs are different. Leaving the HVAC system’s fan on may work for you if:

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

Your home has hot and cold spots. Lots of homes deal with persistent hot and cold spots that quickly shift to a temperature different from the rest of the house. The fan setting should help limit these changes by consistently refreshing each room’s supply of air.