As the weather starts to cool off, you may be wondering about how you’ll take full advantage of your heating and cooling. After all, HVAC costs frequently add up to a big chunk of your monthly electric bill. To figure out new ways to save, some homeowners 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 going during a normal cycle, what will the fan setting provide for your HVAC system? This guide can help. We’ll share just what the fan setting is and when you can use it to save money over the summer or winter.

My Thermostat Has a Fan Setting?

For the majority of thermostats, the fan setting signifies that the air handler’s blower fan remains on. A few furnaces will run at a low level with this setting, but for the most part heating or cooling isn’t being made. The ‘Auto’ setting, conversely, will start the fan over a heating or cooling cycle and switch it off once the cycle is over.

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

Advantages to using 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 should improve because constant airflow will keep forcing airborne contaminants through the air filter.
  • Fewer start-stop cycles for the blower fan helps extend its life span. As the air handler is often part of the furnace, this means you could prevent the need for furnace repair.

Disadvantages to switching to the Fan/On setting:

  • A nonstop fan will likely raise your energy expenses slightly.
  • Nonstop airflow could clog your air filter in a shorter amount of time, 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 linger in unfinished spaces including the attic or an attached garage. If you leave the fan on, your HVAC system can gradually move this warm air into the rest of your home, pushing the HVAC system to work harder to preserve the set temperature. In serious heat, this could lead to needing AC repair more regularly as wear and tear increases.

The opposite can take place over the winter. Cooler spaces like a basement will hold onto cooler air, which will eventually flow into the rest of your home. Leaving the fan setting on may pump 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 switch to the fan/on setting, don’t forget that every home and family’s comfort needs are different. Leaving the HVAC system’s fan on may be best for you if:

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

Your home has hot and cold spots. Many 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.