When the weather is cooling off, you may be thinking about how you’ll prepare your heating and cooling. After all, HVAC bills can add up to a significant portion of your monthly electric bill. To try and find ways to lower their HVAC bill, some homeowners take a closer look at their thermostat. Is there 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 on during a normal cycle, what will the fan setting provide for the HVAC system? This guide will help. We’ll walk through precisely what the fan setting is and whether you can use it to save money in the summer or winter.

My Thermostat Has a Fan Setting?

For most thermostats, the fan setting means that the system’s blower fan keeps running. Certain furnaces can operate at a low level with this setting, but in general heating or cooling isn’t being generated. The ‘Auto’ setting, on the other hand, will run the fan through a heating or cooling cycle and shut it off when the cycle is complete.

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

Advantages to using the Fan/On setting:

  • You can keep the temperature in every room more consistent by allowing the fan to keep generating airflow.
  • Indoor air quality can increase because continuous airflow will keep forcing airborne particles into the air filter.
  • A smaller amount of start-stop cycles for the system’s fan helps lengthen its life span. As the air handler is often part of the furnace, this means you could avoid needing furnace repair.

Downsides to utilizing the Fan/On setting:

  • A nonstop fan can raise your energy bills somewhat.
  • Constant airflow could clog your air filter soon, 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 linger in unfinished spaces like the attic or an attached garage. If you keep the fan running, your HVAC system may gradually move this warm air into the rest of your home, compelling the HVAC system to work harder to maintain the desired temperature. In severe heat, this could lead to needing AC repair more quickly as wear and tear increases.

The reverse can occur over the winter. Cooler spaces like a basement will hold onto cooler air, which will eventually make its way into the rest of your home. Keeping the fan on may pull more cold air upward, increasing the amount of heating you need to stay 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 may work for you if:

Someone in your household suffers from allergies. Allergies and other 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. Many homes wrestle with persistent hot and cold spots that quickly evolve to a temperature different from the rest of the house. The fan setting should help lessen these changes by constantly refreshing each room’s ventilation.