
Once the weather begins to cool off, you are probably wondering about how you’ll prepare your heating and cooling. After all, HVAC expenses routinely add up to a significant portion of your monthly electric bill. To learn new ways to lower their HVAC bill, some homeowners look closer at their thermostat. Could there be a setting they can use to boost efficiency?
Most thermostats come with a ‘Fan’ or ‘Fan On’ setting. But if the fan is going during a typical cycle, what will the fan setting provide for the HVAC system? This guide should 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 the bulk of thermostats, the fan setting signifies that the system's blower fan stays on. Certain furnaces will operate at a low level in this setting, but for the most part heating or cooling isn’t being generated. The ‘Auto’ setting, in contrast, will turn on the fan during a heating or cooling cycle and switch it off once 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 {will|can|should]] depend on your distinct comfort requirements.
Advantages to switching to the Fan/On setting:
- You can keep the temperature in every room more uniform by allowing the fan to keep generating airflow.
- Indoor air quality can increase since continuous airflow will keep forcing airborne particles into the air filter.
- A smaller amount of start-stop cycles for the system's fan helps expand its life span. Because the air handler is often connected to the furnace, this means you might minimize the risk of needing furnace repair.
Drawbacks to switching to the Fan/On setting:
- A continuous fan will likely increase your energy bills somewhat.
- Constant airflow can clog your air filter soon, 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 will sometimes stick around in unfinished spaces like 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, forcing the HVAC system to work harder to maintain the set temperature. In extreme heat, this can lead to 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 may eventually flow into the rest of your home. Keeping the fan on could pull 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, don’t forget 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 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. 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 might help minimize these changes by consistently refreshing each room’s airflow.