Once the weather starts to cool off, you might be thinking about how you’ll prepare your heating and cooling. After all, HVAC expenses can make up a big piece of your monthly electric bill. To learn new ways to lower their HVAC bill, some owners look closely at their thermostat. Maybe there’s a setting they could use to increase 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 the HVAC system? This guide should help. We’ll review precisely what the fan setting is and how you can use it to reduce costs during the summer or winter.

What Is the Fan Setting on My Thermostat?

For the bulk of thermostats, the fan setting signifies that the air handler’s blower fan keeps running. Some furnaces will operate at a low level with this setting, but in general heating or cooling isn’t being produced. 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 complete.

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

Advantages to switching to the Fan/On setting:

  • You can keep the temperature throughout your home more consistent by permitting the fan to keep generating airflow.
  • Indoor air quality can increase as steady airflow will keep moving airborne pollutants through the air filter.
  • Fewer start-stop cycles for the HVAC fan helps lengthen its life span. As the air handler is typically part of the furnace, this means you could avoid needing furnace repair.

Drawbacks to switching to the Fan/On setting:

  • A nonstop fan could raise your energy bills slightly.
  • Constant airflow could clog your air filter soon, increasing the frequency you will want to replace it.

Should My Thermostat Be on Fan or Auto in Summer/Winter

In the summer, warm air can linger in unfinished spaces such as the attic or an attached garage. If you use the fan setting, your HVAC system can draw this warm air into the rest of your home, forcing the HVAC system to work harder to preserve the set temperature. In serious heat, this can result in needing AC repair more often as wear and tear gets worse.

The reverse can occur in the winter. Cooler spaces such as a basement will hold onto cooler air, which will eventually flow into the rest of your home. Keeping the fan on will sometimes draw more cold air upward, increasing the amount of heating you need to stay warm.

If you’re still trying to determine if you should try the fan/on setting, remember that every home and family’s comfort needs are different. Leaving the HVAC system’s fan on might be ideal for you if:

Someone in your household deals with allergies. Allergies and similar respiratory conditions can be stressful on the family. Leaving the fan on is more likely to enhance indoor air quality, helping your family breathe easier.

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