As the weather starts to cool off, you are probably wondering about how you’ll make the most of your heating and cooling. After all, HVAC bills frequently contribute a significant piece of your monthly electric bill. To try and find ways to lower their HVAC bill, some homeowners look closely at their thermostat. Could there be a setting they could use to improve efficiency?

Most thermostats have a ‘Fan’ or ‘Fan On’ setting. But if the fan is on during a normal cycle, what can the fan setting provide for your HVAC system? This guide can help. We’ll review precisely what the fan setting is and how you can use it to cut costs during the summer or winter.

How Do I Access the Fan Setting on My Thermostat?

For the bulk of thermostats, the fan setting signifies that the air handler’s blower fan keeps running. A few furnaces will generate heat at a low level in this setting, but in general heating or cooling isn’t being made. The ‘Auto’ setting, conversely, will turn on the fan through a heating or cooling cycle and turn it off when the cycle is over.

There are advantages and disadvantages to trying the fan setting on your thermostat, and what's ideal {will|can|should]] depend on your distinct comfort needs.

Advantages to using the Fan/On setting:

  • You can keep the temperature in every room more uniform by permitting the fan to keep circulating air.
  • Indoor air quality can increase because constant airflow will keep forcing airborne contaminants into the air filter.
  • A smaller amount of start-stop cycles for the system's fan helps lengthen its life span. Because the air handler is usually connected to the furnace, this means you could avoid needing furnace repair.

Disadvantages to switching to the Fan/On setting:

  • A nonstop fan will likely add to your energy expenses by a small margin.
  • Continuous 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 Summer/Winter

Through the summer, warm air may persist in unfinished spaces like the attic or an attached garage. If you leave the fan on, your HVAC system might gradually move this warm air into the rest of your home, forcing the HVAC system to work more to keep up with the desired temperature. In severe heat, this could result in needing AC repair more regularly as wear and tear increases.

The opposite can occur in the winter. Cooler spaces like a basement will hold onto cooler air, which will eventually make its way into the rest of your home. Leaving the fan running could 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 switch to the fan/on setting, keep in mind that every home and family’s comfort needs are different. Leaving the HVAC system’s fan on could be ideal for you if:

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

Your home experiences hot and cold spots. All kinds of homes wrestle with difficult 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 ventilation.