When the weather starts to cool off, you are probably wondering about how you’ll make the most of your heating and cooling. After all, HVAC costs can contribute a large piece of your monthly electric bill. To learn new ways to save, some homeowners look closer at their thermostat. Could there be a setting they should use to increase efficiency?

The majority of thermostats include both a ‘Fan’ or ‘Fan On’ setting. But if the fan is on during a regular 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 how you can use it to cut costs over the summer or winter.

How Do I Access the Fan Setting on My Thermostat?

For the majority of thermostats, the fan setting means that the air handler’s blower fan remains on. A few furnaces can operate at a low level in this setting, but in general heating or cooling isn’t being produced. The ‘Auto’ setting, conversely, will start the fan through a heating or cooling cycle and switch it off when the cycle is over.

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

Advantages to trying the Fan/On setting:

  • You can keep the temperature in each room more uniform by permitting the fan to keep running.
  • Indoor air quality can increase because constant airflow will keep moving airborne pollutants into the air filter.
  • A smaller number of start-stop cycles for the blower fan helps lengthen its life span. As the air handler is usually a component of the furnace, this means you might prevent the need for furnace repair.

Drawbacks to using the Fan/On setting:

  • A constant fan can raise your energy expenses somewhat.
  • Continuous airflow can clog your air filter soon, increasing the frequency you’ll need to replace it.

Which Setting for My Thermostat? 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 might pull this warm air into the rest of your home, pushing the HVAC system to work more to preserve the desired temperature. In extreme heat, this can lead to needing AC repair more often as wear and tear grows.

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

If you’re still trying to determine if you should switch to the fan/on setting, keep in mind that every home and family’s comfort needs are different. Leaving the HVAC system’s fan on might work for you if:

Someone in your household suffers from 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 experiences hot and cold spots. All kinds of 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 limit these changes by consistently refreshing each room’s supply of air.