When the weather begins to cool off, you might be thinking about how you’ll make the most of your heating and cooling. After all, HVAC expenses frequently contribute a large portion of your monthly electric bill. To try and find ways to save, some homeowners take a closer look at their thermostat. Could there be a setting they should use to increase efficiency?
Most thermostats include both a ‘Fan’ or ‘Fan On’ setting. But if the fan is running during a regular cycle, what can the fan setting offer for your HVAC system? This guide can help. We’ll share just 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 most thermostats, the fan setting indicates that the system's blower fan keeps running. Some furnaces can run at a low level in this setting, but in general heating or cooling isn’t being generated. The ‘Auto’ setting, conversely, will run the fan through a heating or cooling cycle and shut it off when the cycle is finished.
There are advantages and disadvantages to switching on the fan setting on your thermostat, and whether you do or don’t can depend on your distinct comfort needs.
Advantages to trying the Fan/On setting:
- You can keep the temperature in every room more consistent by allowing the fan to keep circulating air.
- Indoor air quality can increase since constant airflow will keep passing airborne contaminants through the air filter.
- Fewer start-stop cycles for the blower fan helps extend its life span. Since the air handler is usually part of the furnace, this means you might minimize the risk of needing furnace repair.
Downsides to utilizing the Fan/On setting:
- A continuous fan can add to your energy expenses by a small margin.
- Continuous airflow may clog your air filter soon, increasing the frequency you should replace it.
Should My Thermostat Be on Fan or Auto in Summer/Winter
During the summer, warm air will sometimes persist in unfinished spaces like the attic or an attached garage. If you keep the fan running, your HVAC system can draw 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 regularly as wear and tear increases.
The reverse can occur over 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 running may pull 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, remember that every home and family’s comfort needs are not the same. Leaving the HVAC system’s fan on might be best for you if:
Someone in your household has allergies. Allergies and similar respiratory conditions can be stressful on the family. Leaving the fan on should help to improve indoor air quality, helping your family breathe easier.
Your home experiences hot and cold spots. All kinds of homes deal with persistent hot and cold spots that quickly evolve to a temperature different from the rest of the house. The fan setting might help lessen these changes by consistently refreshing each room’s ventilation.