When the weather begins to cool off, you might be wondering about how you’ll prepare your heating and cooling. After all, HVAC costs routinely contribute a significant chunk of your monthly electric bill. To learn new ways to save, some owners take a closer look at their thermostat. Is there a setting they could use to boost efficiency?
The majority of thermostats include both a ‘Fan’ or ‘Fan On’ setting. But if the fan is running during a typical cycle, what does the fan setting provide for an HVAC system? This guide can help. We’ll share what exactly the fan setting is and whether you can use it to reduce costs in the summer or winter.
What Is the Fan Setting on My Thermostat?
For most thermostats, the fan setting indicates that the air handler’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 start the fan during a heating or cooling cycle and switch it off after the cycle is over.
There are benefits and drawbacks to using the fan setting on your thermostat, and what's ideal should depend on your personal comfort requirements.
Advantages to trying the Fan/On setting:
- You can keep the temperature in each room more uniform by enabling the fan to keep circulating air.
- Indoor air quality can increase since constant airflow will keep passing airborne particles into the air filter.
- A smaller number of start-stop cycles for the HVAC fan helps extend its life span. Because the air handler is usually a component of the furnace, this means you could minimize the risk of needing furnace repair.
Drawbacks to using the Fan/On setting:
- A constant fan will likely increase your energy expenses by a small margin.
- Continuous 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 stick around in unfinished spaces like the attic or an attached garage. If you use the fan setting, your HVAC system might pull this warm air into the rest of your home, forcing the HVAC system to run longer to preserve the preferred temperature. In serious heat, this may result in needing AC repair more regularly as wear and tear grows.
The opposite can happen during 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 may pump 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 suffers from allergies. Allergies and other respiratory conditions can be stressful on the family. Leaving the fan on is more likely to improve indoor air quality, helping your family breathe easier.
Your home deals with hot and cold spots. All kinds of homes deal with persistent hot and cold spots that quickly return to a temperature different from the rest of the house. The fan setting can help minimize these changes by consistently refreshing each room’s airflow.