
As the weather starts to cool off, you may be wondering about how you’ll take full advantage of your heating and cooling. After all, HVAC expenses can add up to a significant chunk of your monthly electric bill. To learn new ways to reduce costs, some people look closer at their thermostat. Maybe there’s a setting they should use to improve efficiency?
The bulk of thermostats have a ‘Fan’ or ‘Fan On’ setting. But if the fan is going during a normal cycle, what does the fan setting offer for the HVAC system? This guide will help. We’ll walk through precisely what the fan setting is and whether you can use it to save money in the summer or winter.
What Is the Fan Setting on My Thermostat?
For the majority of thermostats, the fan setting indicates that the system's blower fan keeps running. Certain furnaces can operate at a low level with this setting, but in most cases heating or cooling isn’t being generated. The ‘Auto’ setting, on the other hand, will run the fan over a heating or cooling cycle and switch it off when the cycle is finished.
There are pros and cons to trying the fan setting on your thermostat, and whether you do or don’t {will|can|should]] depend on your distinct comfort needs.
Advantages to using the Fan/On setting:
- You can keep the temperature in every room more balanced by permitting the fan to keep generating airflow.
- Indoor air quality will be highest as steady airflow will keep passing airborne pollutants through the air filter.
- Fewer start-stop cycles for the HVAC fan helps extend its life span. As the air handler is often connected to the furnace, this means you could prevent the need for furnace repair.
Disadvantages to switching to the Fan/On setting:
- A constant fan could increase your energy costs somewhat.
- Nonstop airflow can clog your air filter up more quickly, increasing the frequency you’ll need to replace it.
Should My Thermostat Be on Fan or Auto in Summer/Winter
In the summer, warm air can linger in unfinished spaces such as the attic or an attached garage. If you keep the fan running, your HVAC system might gradually move this warm air into the rest of your home, forcing the HVAC system to run longer to preserve the preferred temperature. In extreme heat, this can lead to needing AC repair more often as wear and tear increases.
The reverse can happen during the winter. Cooler spaces like a basement will hold onto cooler air, which may eventually drift into the rest of your home. Leaving the fan setting on may draw more cold air upward, increasing the amount of heating you need to remain warm.
If you’re still trying to figure out if you should try 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 work for you if:
Someone in your household has 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. Lots of homes deal with stubborn hot and cold spots that quickly shift to a temperature different from the rest of the house. The fan setting should help lessen these changes by consistently refreshing each room’s airflow.