When the weather is cooling off, you might be concerned about how you’ll take full advantage of your heating and cooling. After all, HVAC expenses can make up a significant piece of your monthly electric bill. To try and find ways to lower their HVAC bill, some owners look closely at their thermostat. Is there a setting they could use to improve efficiency?

The bulk of thermostats include both a ‘Fan’ or ‘Fan On’ setting. But if the fan is running during a regular cycle, what will the fan setting offer for the HVAC system? This guide can help. We’ll share just what the fan setting is and how you can use it to cut costs during the summer or winter.

How Do I Access the Fan Setting on My Thermostat?

For the majority of thermostats, the fan setting signifies that the air handler’s blower fan remains on. Certain furnaces may continue to operate at a low level with this setting, but in most cases heating or cooling isn’t being generated. The ‘Auto’ setting, on the other hand, will start the fan during a heating or cooling cycle and switch it off when the cycle is finished.

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

Advantages to utilizing the Fan/On setting:

  • You can keep the temperature in each room more uniform by enabling the fan to keep circulating air.
  • Indoor air quality can increase as constant airflow will keep forcing airborne pollutants into the air filter.
  • A smaller number of start-stop cycles for the system's fan helps extend its life span. Since the air handler is often connected to the furnace, this means you might minimize the risk of needing furnace repair.

Downsides to utilizing the Fan/On setting:

  • A constant fan will likely increase your energy costs slightly.
  • Nonstop airflow could 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

In the summer, warm air may linger in unfinished spaces like 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, forcing the HVAC system to work more to maintain the preferred temperature. In serious heat, this may result in needing AC repair more regularly as wear and tear increases.

The reverse can take place during the winter. Cooler spaces like a basement will hold onto cooler air, which may eventually drift into the rest of your home. Leaving the fan setting on may pull 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, keep in mind that every home and family’s comfort needs are different. Leaving the HVAC system’s fan on may be ideal for you if:

Someone in your household has allergies. Allergies and similar respiratory conditions can be hard on the family. Leaving the fan on should help to improve 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 airflow.