When the weather is cooling off, you might be wondering about how you’ll take full advantage of your heating and cooling. After all, HVAC bills can make up a big piece of your monthly electric bill. To figure out new ways to reduce costs, some homeowners look closely at their thermostat. Is there a setting they could use to increase efficiency?

The majority of thermostats come with a ‘Fan’ or ‘Fan On’ setting. But if the fan is going during a normal cycle, what does the fan setting offer for your HVAC system? This guide should help. We’ll walk through just what the fan setting is and how you can use it to save money over the summer or winter.

My Thermostat Has a Fan Setting?

For the bulk of thermostats, the fan setting indicates that the air handler’s blower fan keeps running. Some furnaces will generate heat at a low level with this setting, but for the most part heating or cooling isn’t being produced. The ‘Auto’ setting, on the other hand, will start the fan through a heating or cooling cycle and shut it off after the cycle is finished.

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

Advantages to using the Fan/On setting:

  • You can keep the temperature throughout your home more uniform by enabling the fan to keep circulating air.
  • Indoor air quality can increase because steady airflow will keep passing airborne contaminants through the air filter.
  • Fewer start-stop cycles for the HVAC fan helps extend its life span. As the air handler is typically a component of the furnace, this means you might minimize the risk of needing furnace repair.

Disadvantages to switching to the Fan/On setting:

  • A continuous fan could increase your energy bills slightly.
  • Nonstop 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

During the summer, warm air will sometimes stick around in unfinished spaces including the attic or an attached garage. If you leave the fan on, your HVAC system might draw this warm air into the rest of your home, compelling the HVAC system to work harder to maintain the set temperature. In serious heat, this may lead to needing AC repair more regularly as wear and tear grows.

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

If you’re still trying to decide if you should try the fan/on setting, keep in mind that every home and family’s comfort needs are different. Leaving the HVAC system’s fan on might work for you if:

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

Your home deals with hot and cold spots. All kinds 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 lessen these changes by steadily refreshing each room’s supply of air.