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

Most thermostats come with a ‘Fan’ or ‘Fan On’ setting. But if the fan is going during a typical cycle, what will the fan setting offer for the HVAC system? This guide can help. We’ll review just what the fan setting is and when you can use it to reduce costs in the summer or winter.

How Do I Access the Fan Setting on My Thermostat?

For most thermostats, the fan setting indicates that the system’s blower fan stays on. Certain furnaces may continue to operate at a low level with this setting, but in general heating or cooling isn’t being produced. The ‘Auto’ setting, on the other hand, will run the fan through a heating or cooling cycle and switch it off once the cycle is finished.

There are pros and cons to switching on the fan setting on your thermostat, and the ideal option {will|can|should]] depend on your unique comfort requirements.

Advantages to switching to the Fan/On setting:

  • You can keep the temperature in every room more balanced by permitting the fan to keep circulating air.
  • Indoor air quality will be highest as continuous airflow will keep passing airborne pollutants into the air filter.
  • A smaller number of start-stop cycles for the blower fan helps expand its life span. Since the air handler is usually a component of the furnace, this means you can minimize the risk of needing furnace repair.

Disadvantages to using the Fan/On setting:

  • A continuous fan will likely raise your energy bills slightly.
  • Nonstop airflow may clog your air filter soon, increasing the frequency you will want to 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 will sometimes persist in unfinished spaces including 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 harder to preserve the desired temperature. In serious heat, this may lead to needing AC repair more regularly as wear and tear gets worse.

The reverse can occur over the winter. Cooler spaces like a basement will hold onto cooler air, which can eventually make its way 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, keep in mind that every home and family’s comfort needs are not the same. Leaving the HVAC system’s fan on may be ideal for you if:

Someone in your household deals with 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 deals with hot and cold spots. All kinds of homes deal with persistent 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 consistently refreshing each room’s airflow.