The differences between whole house fans and traditional air conditioners are vast. The major differences come from how they cool homes and why one is much more effective than the other.
Traditional Air conditioners have become a home staple and have worked to cool homes for decades. They are not, however, the perfect cooling system. They do what their name suggests, condition air, but they do not get all of the air in a home and condition simply means to bring something into the desired state.
Traditional Air conditioners are really good at getting your home to the temperature you desire but they are not as good at keeping it that temperature. Like their name suggests, they bring the air in your home to your desired temperature.
If you want to keep it the temperature you desire, that means running your A/C around the clock which, as many know, is exceedingly expensive and bothersome. The reason they are not great at keeping a home cool is that they mainly cool the bottom of a home.
The top of icebergs are the ones that you see constantly on national geographic and other documentaries. They are the part that gets the most sun and get the hottest. The bottom is much larger and colder while being submerged under water. Homes are kind of like icebergs in this way.
As much as you cool the bottom of the house, the attic, the top of the iceberg, will still be hot. That is the air that most traditional air conditioners miss and the area that can get the hottest. The top of the home iceberg can reach temperatures of over 150 degrees Fahrenheit. The traditional air conditioner, even when on, does nothing to combat the attic and is constantly at war with it.
Just as the A/C cools the home, the attic heats it back up. Imagine if you cooled just 80% of your refrigerator. Where you put all of your groceries and perishables would be nice and cool but the shelf that is unused received no cool air and it even pumped in hot air from outside. It would not only affect that one shelf but the entire fridge.
This is why you have to run the A/C constantly. It misses a large and crucial part of a home and never gets the entire house.
Whole house fans, however, do get the entire home including the attic.
They pull an abundant amount of air from the home and attic and push the hot air out of attic vents while bringing in fresh and cool air from outside. This not only works to cool the bottom of the home iceberg but the top, which then keeps the entire home cool. This is the crucial part of how they work and why their name is equally as honest as that of the air conditioner.
They really do get the whole house.
Traditional Air conditioners are fantastic at getting your home to the temperature you want but whole house fans are great at keeping your home to the temperature you want and it is all because of the top of that iceberg.