The old-time ceiling fan cools -- and heats
A tug on the cord starts the paddle-bladed ceiling fan turning. Seconds later wafts of cooling air, like a gentle sea breeze, wash around us on the floor below.
On this torrid late-August day, the moving air refreshes us and it is difficult to appreciate that in the colder months that lie ahead, these same blades will warm us, too. Yet this is precisely what this relic of the Victorian age can do for us.
Russ Sears has given me this demonstration. He sells hardware -- everything from a carpet tack to a radial-arm saw -- in a store just across the road here from the oldest continuously operating church in the United States. He also dispenses free advice on how best to use the various products he sells. And this year, more than anything else, folks have been seeking his advice on fans -- how to install them and how best to use them for both cooling and heating.
As energy costs continue to rise, fans are coming back into their own from the smallest desktop fans to attic fans designed to cool an entire house. Right now all fan styles, particularly the old-time ceiling variety, are a hot retail item in stores everywhere.
"We thought we had stocked up with more than enough fans for the whole year," says Mr. Sears, "but by midsummer we were all but cleaned out." Similar tales are coming in from dealers everywhere.
The reasons are easy to find. A small bedside fan can keep a gentle cooling breeze blowing across the bed for pennies a night, compared with the high cost of an air conditioner; the old-fashioned ceiling fan will do the same thing while expending no more energy than is used to burn a single 100-watt light bulb.
In winter that ceiling fan conserves energy by pumping ceiling-hugging warm air backt o floor level. Other fans also improve winter comfort by distributing air from a heated room to more distant regions of the house. In fact, says Mr. Sears, "it is remarkable the way fan sales have paralleled the sale fo wood and coal stoves."
Many people, it seems, install a stove one season and return the next with the question: How can I spread some of my living-room heat around?
The answer, says Mr. Sears, is to use a fan. In the older-style box houses, natural convection carries warm air to the rooms up above; it is in ranch houses that the fan becomes most important in redistributing warm air.
Of them all the paddle-bladed ceiling fan is enjoying the most remarkable resurgence. From its introduction in 1880 through the 1930s it was popular worldwide, particularly in the US and in the hot and humid regions of the British Empire. Now its return is being parked, in part by nostalgia, but mostly because it is effective and relatively inexpensive.
Take the coming winter months. In a typical factory, air temperatures can range from 60 degrees F. at floor level to 90 degrees in the top two feet below the ceiling where the heat slowly conducts through the roof and is wasted. The constant feeding in of heat to warm the lower working levels is expensive so that, in many cases, the installation of large ceiling fans has cut heating bills by up to 30 percent.
The ceiling fans work this way: They continually take the hot air that gathers just below the ceiling and force it back down to the working area. In effect, they recycle the warm air. This satisfies much of the demand of the thermostat so that it calls for heat from the furnace less frequently. At the same time the workers are comfortably warm.
That same stratified air, that ranges from 60 to 90 degrees, provides a comfortable 70 degrees when the air is mixed up -- or homogenized, as some term it.
What happens in the factory happens in the private home, particularly one that is heated by warm air. While the difference between the temperature around your ankles and the temperature around the hand which you extend above your head may not be as great as 30 degrees, it can readily fall in the 10-degree- and-higher range, depending on ceiling height.
Last winter I conducted a simple test in a hot-air-heated room with 12-foot ceilings. While the temperature at desk level stood at 54 degrees F., 6 inches below the ceiling the thermometer registered 92 degrees, an almost 40-degree difference.
One thought to remember: The ceiling fan should only be installed in rooms where the ceiling is at least 8 feet high. If there are any basketball players in your family, even 8 feet might prove too low.
Ceiling fans extend down a minimum of 12 inches -- and no one wants to get a "brush cut" from the revolving blades. On the other hand, a small conventional fan mounted high up on the wall, and pointing down at an angle of 45 degrees or thereabouts, will do a similar, even if not quite so effective, job.
Gently moving air, according to the American Ventilation Association, can make 85 degree F. temperatures feel like 78 degrees in still air because of the evaporative cooling effect induced by moving air. The latter temperature is within the comfort zone of most people; the former is not. On a muggy Boston evening a few weeks ago, the 90-degree temperature of my bedroom was made tolerable by the steady breeze of the fan all night long.
The American Ventilation Association suggests that fans, particularly the attic or whole-house type, can handle all cooling needs when temperatures rise no higher than the mid to upper 80s. Even then the demands on air-conditioning units can be reduced with the help of fans because cool air feels even cooler on the skin when gently stirred. In other words, with the help of a fan or two you can set your air-conditioning thermostat at 80 degrees F. or even higher.
Not many people realize that the cost of refrigerated cooling (air conditioners) is considerably higher than the cost of heating. So a fan's contribution to economy in the home can be considerable. For this reason attic or whole-house fans now are in demand. These fans, generally installed in a ceiling, force out hot attic air at the same time they draw cooler night air into the house.
Often in the confined hot-box conditions of an attic, the temperature builds up to 30 degrees higher than the outside air temperature. This heats up the ceiling which, in turn, radiates unwanted heat into the house. Hence, the importance of getting rid of that attic air on hot days.
The idea of the attic fan is to draw outside air into the houe when it is coolest -- at sunrise -- after which the windows and doors are closed and the drapes drawn. In an insulated home, the indoor temperature will rise only around half a degree an hour. So a house that is 70 degrees at 7 in the morning is a comfortable 76 to 80 degrees by 7 in the evening while outside temperatures may have soared to 98 or 100 degrees.
while in the North a whole-house fan might provide all the cooling necessary, the hotter South will certainly need some air-conditioning assistance these days. But even this can be limited only to the torrid months of summer for a big saving in the electricity bill while the house fan takes care of spring and fall cooling needs.