As the weather is cooling off, you are probably concerned about how you’ll prepare your heating and cooling. After all, HVAC costs can make up a large piece of your monthly electric bill. To try and find ways to lower their HVAC bill, some people look closer at their thermostat. Could there be a setting they should use to boost efficiency?

Most thermostats have a ‘Fan’ or ‘Fan On’ setting. But if the fan is running during a normal cycle, what can the fan setting provide for the HVAC system? This guide should help. We’ll share precisely what the fan setting is and when you can use it to save money over the summer or winter.

Should I Use My Thermostat's Fan Setting?

For the bulk of thermostats, the fan setting means that the air handler’s blower fan keeps running. A few furnaces will run at a low level with this setting, but in general heating or cooling isn’t being made. The ‘Auto’ setting, on the other hand, will turn on the fan during a heating or cooling cycle and switch it off after 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 utilizing the Fan/On setting:

  • You can keep the temperature in every room more consistent by enabling the fan to keep running.
  • Indoor air quality will be highest because continuous airflow will keep moving airborne pollutants through the air filter.
  • Fewer start-stop cycles for the system's fan helps expand its life span. Because the air handler is often a component of the furnace, this means you could prevent the need for furnace repair.

Drawbacks to using the Fan/On setting:

  • A constant fan could increase your energy expenses somewhat.
  • Constant airflow may clog your air filter up more quickly, increasing the frequency you’ll need to replace it.

{Choosing Between|Should My Thermostat Be on|Which Setting for My Thermostat? Fan or Auto in Each Season

Through the summer, warm air will sometimes stick around in unfinished spaces including the attic or an attached garage. If you keep the fan running, your HVAC system can pull this warm air into the rest of your home, pushing the HVAC system to work more to preserve the desired temperature. In severe heat, this may lead to needing AC repair more often as wear and tear grows.

The reverse can happen during the winter. Cooler spaces such as a basement will hold onto cooler air, which will eventually flow into the rest of your home. Leaving the fan running 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, remember that every home and family’s comfort needs are not the same. Leaving the HVAC system’s fan on could be best 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 should help to enhance indoor air quality, helping your family breathe easier.

Your home deals with hot and cold spots. All kinds of homes wrestle with persistent hot and cold spots that quickly evolve to a temperature different from the rest of the house. The fan setting might help limit these changes by consistently refreshing each room’s airflow.