Wednesday, November 28, 2007

Whole House Fans - An Energy Efficient Alternative To Home Cooling

Whole House Fans - Summer time in Southern California brings along warm temperatures and large electricity bills. For those of us without the modern convenience of central air conditioning, we have a time of year when tempers flair and households can seem just a little edgy. For those of us with central air, we know very well that installing a central air conditioning system is not only fairly expensive to purchase, but also pricey to operate. To help combat high energy bills or just cool an uncomfortably warm home, we have a great alternative to the normal solutions of window units, room units, and ceiling fans.

This alternative is known as a whole house fan and does almost exactly what the name implies. Instead of circulating or blowing the same warm air as some of the above solutions do, a whole house fan pulls cool air from outside into the home and pushes (actually pulls) the warm air out through the attic vents. The result is that you can quickly cool your home to approximately the same temperature as the outside air. Most of the time, especially evenings when most return from work, this air is considerably cooler than what has been bottled up in the home all day. Of course you could get the same effect on a breezy evening by opening all the windows but it would take considerably longer and the breeze is never guaranteed.

There are a few requirements when you decide to operate a whole house fan. First, you need to have adequate clearance in the attic. Usually you won't need much more than a couple feet. Second, there must be appropriate ventilation in the attic for the warm air to escape. This would be a good time to differentiate one point. A whole house fan IS NOT the same as an attic fan. An attic fan merely pulls hot air out of the attic but does not pull it out of the home nor does it bring the cool air in. The two types of fans are best when used in conjunction with one another.

To use a whole house fan, one must open some windows when in use. Opening one window in a single room will quickly cool that room while opening up the entire home will more gradually cool the whole living space. Both methods have their respective time and places.

Whole house fans come in different sizes with a variety of different features. We have seen models from 24-30 inches in diameter but the actual size is a little larger after adding the vent cover. Multiple speeds and wall switches seem to be some of the more popular features.

We've seen fans costing between $180-250 depending on size, manufacturer, and features. Installation of the fan is extra and can be done in a few hours by a reputable contractor. Currently, Southern California Edison is givin $50 rebates for these fans but one should always check first for current program availability. For the do-it-yourselfers, please note that installation will require careful thought regarding placement as well as some light carpentry and electrical work. We would recommend anybody concerned with their ability to properly install the fan contact a licensed reputable contractor.

Although these fans can be a real blessing during summer heat waves, they are not without their limitations. Whole house fans can only cool the inside temperature to the approximate temperature of the outside air. If the outside air is 100 degrees, the house won't get much cooler than that. So if one has central air conditioning, there are some days when it will just need to be used in order to cool the home. Regardless, many summer mornings, evenings, and nights in Orange and Los Angeles Counties are cool enough to really make the whole house fan a sanity and money saver!