As the weather starts to cool off, you are probably concerned about how you’ll prepare your heating and cooling. After all, HVAC expenses can add up to a big portion of your monthly electric bill. To try and find ways to lower their HVAC bill, some people look closely at their thermostat. Maybe there’s a setting they should use to improve efficiency?

Most thermostats include both a ‘Fan’ or ‘Fan On’ setting. But if the fan is on during a normal cycle, what will the fan setting provide for the HVAC system? This guide should help. We’ll walk through just what the fan setting is and when you can use it to cut costs in the summer or winter.

My Thermostat Has a Fan Setting?

For the majority of thermostats, the fan setting signifies that the HVAC blower fan keeps running. A few furnaces will generate heat at a low level with this setting, but for the most part heating or cooling isn’t being made. The ‘Auto’ setting, conversely, will run the fan over 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 needs.

Advantages to switching to the Fan/On setting:

  • You can keep the temperature in each room more balanced by enabling the fan to keep circulating air.
  • Indoor air quality will be highest as continuous airflow will keep forcing airborne contaminants through the air filter.
  • Fewer start-stop cycles for the system’s fan helps lengthen its life span. As the air handler is usually part of the furnace, this means you could prevent the need for furnace repair.

Downsides to using the Fan/On setting:

  • A nonstop fan can increase your energy bills somewhat.
  • 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 Each Season

During the summer, warm air may stick around in unfinished spaces like the attic or an attached garage. If you leave the fan on, your HVAC system can draw this warm air into the rest of your home, pushing the HVAC system to work harder to maintain the preferred 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 like a basement will hold onto cooler air, which may eventually make its way into the rest of your home. Keeping the fan on may pump more cold air upward, increasing the amount of heating you need to remain warm.

If you’re still trying to determine if you should use the fan/on setting, remember that every home and family’s comfort needs are not the same. Leaving the HVAC system’s fan on may work for you if:

Someone in your household has allergies. Allergies and similar respiratory conditions can be tough 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 shift to a temperature different from the rest of the house. The fan setting might help lessen these changes by consistently refreshing each room’s ventilation.