Skip to content
As the weather begins to cool off, you may be thinking about how you’ll make the most of your heating and cooling. After all, HVAC expenses frequently add up to a large portion of your monthly electric bill. To figure out new ways to reduce costs, some homeowners take a closer look at their thermostat. Is there a setting they can use to improve efficiency?
The majority of thermostats have a ‘Fan’ or ‘Fan On’ setting. But if the fan is on during a regular cycle, what does the fan setting provide for the HVAC system? This guide should help. We’ll review just what the fan setting is and when 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 indicates that the air handler’s blower fan stays on. Certain furnaces can run at a low level in this setting, but in most cases heating or cooling isn’t being made. The ‘Auto’ setting, in contrast, will start the fan during a heating or cooling cycle and turn it off once the cycle is finished.
There are advantages and disadvantages to using the fan setting on your thermostat, and the ideal option {will|can|should]] depend on your personal comfort preferences.
Advantages to trying the Fan/On setting:
- You can keep the temperature in each room more consistent by permitting the fan to keep circulating air.
- Indoor air quality will be highest as constant airflow will keep forcing airborne contaminants through the air filter.
- A smaller number of start-stop cycles for the system's fan helps lengthen its life span. Because the air handler is often connected to the furnace, this means you might prevent the need for furnace repair.
Downsides to using the Fan/On setting:
- A constant fan will likely raise your energy bills somewhat.
- Nonstop airflow could clog your air filter in a shorter amount of time, increasing the frequency you should replace it.
Should My Thermostat Be on Fan or Auto in Summer/Winter
Through the summer, warm air may stick around in unfinished spaces including the attic or an attached garage. If you use the fan setting, your HVAC system can gradually move this warm air into the rest of your home, compelling the HVAC system to work harder to preserve the desired temperature. In extreme heat, this may lead to needing AC repair more regularly as wear and tear increases.
The opposite can happen over the winter. Cooler spaces such as a basement will hold onto cooler air, which will eventually flow 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 keep warm.
If you’re still trying to figure out if you should switch to the fan/on setting, remember that every home and family’s comfort needs are different. Leaving the HVAC system’s fan on could 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 can help to enhance indoor air quality, helping your family breathe easier.
Your home has hot and cold spots. Many homes deal with stubborn hot and cold spots that quickly return to a temperature different from the rest of the house. The fan setting might help lessen these changes by constantly refreshing each room’s ventilation.