When the weather is cooling off, you may be wondering about how you’ll make the most of your heating and cooling. After all, HVAC bills can contribute a significant chunk of your monthly electric bill. To learn new ways to reduce costs, some homeowners look closer at their thermostat. Maybe there’s a setting they could use to increase efficiency?

The bulk of thermostats include both a ‘Fan’ or ‘Fan On’ setting. But if the fan is running during a typical cycle, what can the fan setting provide for an HVAC system? This guide will help. We’ll share what exactly the fan setting is and when you can use it to reduce costs in the summer or winter.

What Is the Fan Setting on My Thermostat?

For most thermostats, the fan setting signifies that the system’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 run the fan during a heating or cooling cycle and switch it off once the cycle is complete.

There are advantages and disadvantages to switching on the fan setting on your thermostat, and the ideal option {will|can|should]] depend on your unique comfort needs.

Advantages to using the Fan/On setting:

  • You can keep the temperature in each room more uniform by enabling the fan to keep running.
  • Indoor air quality can increase since constant airflow will keep passing airborne contaminants through the air filter.
  • Fewer start-stop cycles for the system’s fan helps extend its life span. As the air handler is often a component of the furnace, this means you might minimize the risk of needing furnace repair.

Drawbacks to using the Fan/On setting:

  • A constant fan will likely add to your energy costs somewhat.
  • Continuous airflow may clog your air filter up more quickly, 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

Through the summer, warm air will sometimes persist in unfinished spaces like the attic or an attached garage. If you keep the fan running, your HVAC system can gradually move this warm air into the rest of your home, forcing the HVAC system to run longer to maintain the set temperature. In severe heat, this can lead to needing AC repair more quickly as wear and tear increases.

The opposite can happen in the winter. Cooler spaces like a basement will hold onto cooler air, which can eventually drift 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, keep in mind that every home and family’s comfort needs are not the same. Leaving the HVAC system’s fan on may be ideal for you if:

Someone in your household deals with allergies. Allergies and other respiratory conditions can be stressful on the family. Leaving the fan on should help to increase indoor air quality, helping your family breathe easier.

Your home experiences hot and cold spots. Lots of homes deal with stubborn hot and cold spots that quickly evolve to a temperature different from the rest of the house. The fan setting should help minimize these changes by constantly refreshing each room’s airflow.