When the weather starts to cool off, you may be wondering about how you’ll make the most of your heating and cooling. After all, HVAC bills can make up a big piece of your monthly electric bill. To try and find ways to reduce costs, some people take a closer look at their thermostat. Could there be a setting they should use to boost efficiency?
The majority of thermostats include both a ‘Fan’ or ‘Fan On’ setting. But if the fan is on during a regular cycle, what does the fan setting provide for an HVAC system? This guide should help. We’ll share precisely what the fan setting is and how you can use it to cut costs in the summer or winter.
What Is the Fan Setting on My Thermostat?
For most thermostats, the fan setting signifies that the HVAC blower fan remains on. Some furnaces will generate heat at a low level with this setting, but in most cases heating or cooling isn’t being produced. The ‘Auto’ setting, conversely, will run the fan over a heating or cooling cycle and shut it off once the cycle is complete.
There are pros and cons to switching on the fan setting on your thermostat, and whether you do or don’t can depend on your personal comfort needs.
Advantages to switching to the Fan/On setting:
- You can keep the temperature in every room more balanced by permitting the fan to keep running.
- Indoor air quality can increase as constant airflow will keep passing airborne pollutants into the air filter.
- A smaller number of start-stop cycles for the HVAC fan helps lengthen its life span. Because the air handler is typically part of the furnace, this means you could avoid needing furnace repair.
Drawbacks to using the Fan/On setting:
- A constant fan could raise your energy expenses 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
In the summer, warm air will sometimes linger in unfinished spaces including the attic or an attached garage. If you use the fan setting, your HVAC system may gradually move this warm air into the rest of your home, forcing the HVAC system to work harder to maintain the preferred temperature. In severe heat, this can result in needing AC repair more regularly as wear and tear grows.
The opposite can happen in the winter. Cooler spaces such as a basement will hold onto cooler air, which can eventually drift into the rest of your home. Leaving the fan running could pump more cold air upward, increasing the amount of heating you need to remain warm.
If you’re still trying to decide if you should try the fan/on setting, keep in mind that every home and family’s comfort needs are different. Leaving the HVAC system’s fan on may work for you if:
Someone in your household deals with allergies. Allergies and similar respiratory conditions can be hard on the family. Leaving the fan on should help to improve indoor air quality, helping your family breathe easier.
Your home has hot and cold spots. Lots of homes wrestle with persistent hot and cold spots that quickly return to a temperature different from the rest of the house. The fan setting should help limit these changes by consistently refreshing each room’s airflow.