Once the weather begins to cool off, you are probably thinking about how you’ll prepare your heating and cooling. After all, HVAC expenses frequently add up to a significant chunk of your monthly electric bill. To learn new ways to reduce costs, some owners look closer at their thermostat. Is there a setting they could use to improve efficiency?
The bulk of thermostats have a ‘Fan’ or ‘Fan On’ setting. But if the fan is running during a normal cycle, what will the fan setting provide for the HVAC system? This guide can help. We’ll walk through just what the fan setting is and whether you can use it to save money during the summer or winter.
What Is the Fan Setting on My Thermostat?
For the majority of thermostats, the fan setting means that the air handler’s blower fan keeps running. Certain furnaces will run at a low level with this setting, but in general heating or cooling isn’t being generated. The ‘Auto’ setting, in contrast, will start the fan over a heating or cooling cycle and switch it off after the cycle is complete.
There are benefits and drawbacks to trying the fan setting on your thermostat, and whether you do or don’t {will|can|should]] depend on your personal comfort preferences.
Advantages to using the Fan/On setting:
- You can keep the temperature throughout your home more balanced by allowing the fan to keep running.
- Indoor air quality will be highest because continuous airflow will keep moving airborne contaminants into the air filter.
- Fewer start-stop cycles for the blower fan helps expand its life span. Because the air handler is typically part of the furnace, this means you could avoid needing furnace repair.
Disadvantages to using the Fan/On setting:
- A constant fan could increase your energy costs slightly.
- Constant airflow may clog your air filter in a shorter amount of time, increasing the frequency you will want to replace it.
Should My Thermostat Be on Fan or Auto in Summer/Winter
Through the summer, warm air can linger in unfinished spaces like the attic or an attached garage. If you use the fan setting, your HVAC system might pull this warm air into the rest of your home, compelling the HVAC system to work more to maintain the set temperature. In severe heat, this could result in needing AC repair more quickly as wear and tear grows.
The opposite can happen over the winter. Cooler spaces like a basement will hold onto cooler air, which may eventually flow into the rest of your home. Leaving the fan running may draw more cold air upward, increasing the amount of heating you need to remain warm.
If you’re still trying to determine if you should switch to the fan/on setting, remember that every home and family’s comfort needs are not the same. Leaving the HVAC system’s fan on could be best for you if:
Someone in your household deals with 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 deals with hot and cold spots. All kinds of homes wrestle 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.