Once the weather starts to cool off, you are probably concerned about how you’ll make the most of your heating and cooling. After all, HVAC expenses routinely make up a big piece of your monthly electric bill. To learn new ways to save, some homeowners look closely at their thermostat. Maybe there’s a setting they should use to increase efficiency?
The majority of thermostats come with a ‘Fan’ or ‘Fan On’ setting. But if the fan is going during a typical cycle, what does the fan setting provide 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 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 remains on. Some furnaces will generate heat 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 during a heating or cooling cycle and switch it off when the cycle is finished.
There are advantages and disadvantages to using the fan setting on your thermostat, and what's ideal should depend on your personal comfort preferences.
Advantages to trying the Fan/On setting:
- You can keep the temperature throughout your home more balanced by enabling the fan to keep circulating air.
- Indoor air quality can increase because constant airflow will keep forcing airborne particles into 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 can minimize the risk of needing furnace repair.
Disadvantages to switching to the Fan/On setting:
- A continuous fan will likely increase your energy bills by a small margin.
- Constant airflow may 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
During the summer, warm air will sometimes stick around in unfinished spaces like the attic or an attached garage. If you leave the fan on, your HVAC system might gradually move this warm air into the rest of your home, compelling the HVAC system to run longer to preserve the preferred temperature. In extreme heat, this could lead to needing AC repair more often as wear and tear gets worse.
The reverse can take place during the winter. Cooler spaces like a basement will hold onto cooler air, which will eventually make its way into the rest of your home. Leaving the fan setting on may pump more cold air upward, increasing the amount of heating you need to stay warm.
If you’re still trying to decide if you should switch to the fan/on setting, keep in mind that every home and family’s comfort needs will vary. Leaving the HVAC system’s fan on could be ideal for you if:
Someone in your household has allergies. Allergies and other respiratory conditions can be hard on the family. Leaving the fan on can help to enhance indoor air quality, helping your family breathe easier.
Your home has hot and cold spots. All kinds of homes deal with stubborn hot and cold spots that quickly return to a temperature different from the rest of the house. The fan setting should help lessen these changes by consistently refreshing each room’s supply of air.