As the weather is cooling off, you are probably wondering about how you’ll make the most of your heating and cooling. After all, HVAC bills routinely contribute a significant chunk of your monthly electric bill. To figure out new ways to lower their HVAC bill, some people look closely at their thermostat. Could there be a setting they can use to boost efficiency?

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

What Is the Fan Setting on My Thermostat?

For most thermostats, the fan setting indicates that the system’s blower fan keeps running. Some furnaces will run at a low level in this setting, but in general heating or cooling isn’t being produced. The ‘Auto’ setting, on the other hand, will run the fan over a heating or cooling cycle and switch it off after the cycle is complete.

There are pros and cons to trying the fan setting on your thermostat, and the ideal option {will|can|should]] depend on your personal comfort needs.

Advantages to switching to the Fan/On setting:

  • You can keep the temperature throughout your home more consistent by enabling the fan to keep running.
  • Indoor air quality should improve as constant airflow will keep passing airborne contaminants into the air filter.
  • A smaller number of start-stop cycles for the system’s fan helps lengthen its life span. Because 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 continuous fan will likely increase your energy expenses by a small margin.
  • Continuous 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

In the summer, warm air may persist in unfinished spaces including the attic or an attached garage. If you use the fan setting, your HVAC system may draw this warm air into the rest of your home, pushing the HVAC system to run longer to maintain the preferred temperature. In extreme heat, this could result in needing AC repair more regularly as wear and tear gets worse.

The reverse can happen over 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 will sometimes 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 try the fan/on setting, don’t forget that every home and family’s comfort needs will vary. Leaving the HVAC system’s fan on may be ideal for you if:

Someone in your household deals with allergies. Allergies and similar respiratory conditions can be tough 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. Lots of homes wrestle with persistent hot and cold spots that quickly return to a temperature different from the rest of the house. The fan setting can help minimize these changes by steadily refreshing each room’s airflow.