Cooling Comfort With Whole House Fans
Cooling doesn't have to come from air conditioners. Just sit under a paddle fan and feel what simple air movement can do. Of course, if the dew point is above 70 F, moving air doesn't do much good, you still feel sticky. Fortunately, many parts of the nation don't have oppressive humidity, and whole house fans can really do a nice job of cooling a house and its occupants on hot summer days.
Creating a Breeze
My personal experience with whole house fans allows me to tell you that these machines will do a great job, if you monitor which windows in your house you open and close to feed the fan's appetite for air.
The simple trick is to open the windows in the rooms you are occupying at that point in time. You want a breeze to flow past you, so that you benefit from the fan's work. It is important that you keep windows closed or nearly closed in the rooms that do not have occupants. Why? If you open all of the windows in your house, there is a good chance that just a little air will flow through each room. On the other hand, if you open the windows in just one room, you might create a moderate windstorm in that area as all of the air being sucked by the fan makes its way through the room and up to the attic.
It will take a little practice for you to get a good air flow through your house. Trust me, it will not take long to figure out how to create a smooth flow of air through many rooms.
Types of Drives
There are two types of ways that the fan blades are driven. Many fans have a direct drive connection between the blades and the motor shaft. This method frees you from ever having to adjust a fan belt or replace a broken belt. The other common drive mechanism is the traditional fan belt. A belt driven fan allows the motor to be offset from the blades. A high quality fan with this setup can last for years with little attention. Fan belts made today can resist years of use and high attic temperatures.
Clean the Fans
Whole house fans move vast amounts of air and in that air is always dust. This dust accumulates on the fan blades, the motor and all other surfaces. You can extend the life of the fan motor if you vacuum off this dust at least once a season. Dust that accumulates on the motor housing causes the motor to get hot. Hot motors simply burn up long before their time.
Which Velocity?
When you start to look at fans, you are going to see a big difference in capacity. The air that the fans push is measured in cubic feet per minute (CFM). The opening bid on the minimum amount of air any one moves is 1,000 CFM. You can get fans that move nearly 7,000 CFM.
Moving lots of air in a short amount of time creates a penalty. This penalty is noise. If you have ever been near a large high velocity whole house fan, the noise they create can be deafening. Obviously, the farther away you are from the fan, the noise decreases.
The solution to this problem is to consider low velocity - or low CFM fans. To get comfort from a low velocity system, you may have to fine tune your open and closed window program, but that extra effort may be music to your ears.
Timers
Many people really like whole house fans for the comfort they deliver at night. In fact, they can deliver way too much comfort and actually make you cold. The fan manufacturers know all about this and deal with this by using timers. There are a variety of different timers that allow you to control the fans' on and off cycles and how long each cycle lasts. A timer with your whole house fan is a must.
Ask Around
Ask your friends, neighbors, co-workers if they have a whole house fan. Visit them to see how it feels and sounds. Don't operate it if the house is closed up and ashes are in the fireplace. The voice of experience talking!
Companion Articles: Cooling With Mother Nature and Whole House Fans, Whole House Fan Installation Tips, Whole House Fan Sizes and Manufacturers
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