Once the weather begins to cool off, you are probably wondering about how you’ll prepare your heating and cooling. After all, HVAC expenses frequently contribute a significant portion of your monthly electric bill. To figure out new ways to save, some homeowners take a closer look at their thermostat. Is there a setting they can use to boost efficiency?
The majority of thermostats come with a ‘Fan’ or ‘Fan On’ setting. But if the fan is running during a typical cycle, what does the fan setting provide for the HVAC system? This guide will help. We’ll walk through what exactly the fan setting is and how you can use it to cut costs over the summer or winter.
What Is the Fan Setting on My Thermostat?
For the majority of thermostats, the fan setting means that the system's blower fan keeps running. Some furnaces can operate at a low level with this setting, but for the most part heating or cooling isn’t being generated. The ‘Auto’ setting, conversely, will run the fan over a heating or cooling cycle and turn it off after the cycle is finished.
There are benefits and drawbacks to switching on the fan setting on your thermostat, and whether you do or don’t can depend on your unique comfort requirements.
Advantages to using the Fan/On setting:
- You can keep the temperature throughout your home more uniform by enabling the fan to keep running.
- Indoor air quality will be highest since continuous airflow will keep forcing airborne particles through the air filter.
- A smaller number of start-stop cycles for the system's fan helps expand its life span. Because the air handler is usually connected to the furnace, this means you could minimize the risk of needing furnace repair.
Drawbacks to switching to the Fan/On setting:
- A nonstop fan could add to your energy bills slightly.
- Constant airflow may clog your air filter in a shorter amount of time, increasing the frequency you will want to replace it.
Should My Thermostat Be on Fan or Auto in Summer/Winter
During the summer, warm air can persist in unfinished spaces including the attic or an attached garage. If you keep the fan running, your HVAC system may draw this warm air into the rest of your home, forcing the HVAC system to work more to maintain the preferred temperature. In extreme heat, this may result in needing AC repair more quickly as wear and tear grows.
The opposite can happen over the winter. Cooler spaces such as a basement will hold onto cooler air, which may eventually drift into the rest of your home. Leaving the fan setting on will sometimes draw 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, don’t forget that every home and family’s comfort needs are not the same. Leaving the HVAC system’s fan on might 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 deals with 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 should help minimize these changes by steadily refreshing each room’s airflow.