Should I Have My HVAC System Set to “On” or “Auto”?
What Is The Difference?
If you have your thermostat’s furnace or AC fan set to “On,” the fan will continually run, regardless if your furnace is running through a heating cycle, i.e., whenever your furnace is actually producing heat. If you have your furnace or AC fan set to “Auto,” your system’s fan will run during the heating or cooling cycle only. When your system reaches the temperature you’ve set for it, the fan will shut off until the next cycle.
“On” option––Air is always being cycled through your furnace filtration system when your fan is continually running. The result is better air quality, since particles are constantly being removed from your air. Keeping the fan running also means heating is more evenly distributed throughout your home. No pockets of hot and cold. This also improves the reliability and life span of your system due to decreased starts and stops, somewhat like a car with highway or city driving. Less wear and tear.
“Auto” option––Since the fan only runs when the system tells it to and at the slowest speed necessary for heating, it’s consuming less energy than the “On” option. This translates to decreased energy costs and less money spent by you. Your furnace filter will also last longer, since air isn’t being pushed through it as much.
“On” option––The biggest con to having your fan continually running is the cost involved. It’s going to be expensive (unless you have a variable speed motor), much more than it would be on the “Auto” option. Another downside is you’re going to be replacing your furnace filter more frequently, since your air is being continually cleaned. Also, in the winter, you may feel a little cold from time to time. Since the fan is running even when the furnace isn’t running through a heat cycle, cold air will be blowing through your vents during that time.
“Auto” option––With this option, since there are more starts and stops, there will be more wear and tear on the furnace. With all these starts and stops, there’s also less even distribution of heat. Once the furnace stops, the air is no longer being moved around, resulting in cold spots. Also, since your air isn’t being filtrated 24/7, your house air isn’t as clean.
As you can see, it’s definitely not a clear-cut case of which is better. It’s a matter of what’s better for you here in Scottsdale Arizona. If you would like to discuss these options in more detail, call Scottsdale Air, and one of our expert technicians can answer any of your questions.
At Scottsdale Air, we’ve been providing affordable, top-notch heating and AC services to residents in Arcadia, Phoenix, Scottsdale, Tempe, Paradise Valley, Carefree, Cave Creek, Fountain Hills, Chandler, Mesa, Gilbert, and Ahwatukee since 1947.
Call Us at 480-945-7200
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