When the weather begins to cool off, you may be wondering about how you’ll prepare your heating and cooling. After all, HVAC costs can add up to a large chunk of your monthly electric bill. To learn new ways to reduce costs, some owners look closely at their thermostat. Is there a setting they can use to increase efficiency?

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

Should I Use My Thermostat’s Fan Setting?

For most thermostats, the fan setting signifies that the air handler’s blower fan stays on. A few furnaces can generate heat at a low level with this setting, but in general heating or cooling isn’t being made. The ‘Auto’ setting, conversely, will start the fan over a heating or cooling cycle and shut it off after the cycle is complete.

There are advantages and disadvantages to switching on the fan setting on your thermostat, and the ideal option {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 should improve since constant airflow will keep forcing airborne particles through the air filter.
  • Fewer start-stop cycles for the HVAC fan helps expand its life span. Because the air handler is typically connected to the furnace, this means you can minimize the risk of needing furnace repair.

Drawbacks to switching to the Fan/On setting:

  • A continuous fan could increase your energy costs slightly.
  • 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 Summer/Winter

In the summer, warm air may persist in unfinished spaces including the attic or an attached garage. If you leave the fan on, your HVAC system can pull this warm air into the rest of your home, compelling the HVAC system to run longer to keep up with the set temperature. In extreme heat, this may lead to needing AC repair more quickly as wear and tear grows.

The reverse can occur over the winter. Cooler spaces like a basement will hold onto cooler air, which can eventually flow into the rest of your home. Leaving the fan setting on will sometimes draw more cold air upward, increasing the amount of heating you need to remain warm.

If you’re still trying to figure out 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 be best for you if:

Someone in your household suffers from allergies. Allergies and other respiratory conditions can be tough on the family. Leaving the fan on can help to increase indoor air quality, helping your family breathe easier.

Your home deals with hot and cold spots. Lots of homes wrestle with difficult hot and cold spots that quickly shift to a temperature different from the rest of the house. The fan setting might help minimize these changes by constantly refreshing each room’s airflow.