FIRST THEY were bought for practical rasons. Then it was romantic. Now it's both. The revival of the old-fashioned ceiling fan is such a success that surprised manufacturers can barely keep up with demand.

In the not-so-long-ago days of cheap air conditioning only a few meat markets and bakeries kept them literally "hanging around." Then some crafty restauranteurs took their decorators' advice and installed them. Now everybody's running back to the homestead to locate the old porch fan that kep the flies away from Grandma's lemonade while she rocked away long summer days.

Good luck to thos grandchildren. Collectors think nothing of paying $400 for one of what few originals, however plain, can still be found. Even the ugly brown utilitarian models are prized.

And why not? A breeze is a breeze to the vendors at places like Eastern Market, where no-nonsense models have been zapping insects' radar for years. Ceiling fans are chemical- and asbestos-free and, to boot, they cost practically nothing to run.

Cheap to run doesn't mean cheap to buy, however. Hunter, the oldest name in the business (GE and Westinghouse dropped out long ago), sold its two-blade, bottom of the line model for $8.50 in 1903. Today's base model lists at $160. What you get that your great-grandfather didn't is a five-year warranty and the assurance that comes with a reputation stretching back to 1886. Hunter is still the industry standard.

Not that the others aren't catching up. They capitalize on the appeal of Bogart and the rmance a name can conjure. So many companies have a model named Casa Blanca that the name has practically become synonoymous with the product.

But there's only one Casa Blanca Fan Co. Not even 10 years old, it's hot on the heels of Hunter.

Casa Blanca, from Pasadena, Calif., combined the practicality of a five-year warranty with the appeal of a catalogue full of names instead of numbers. Only by reading the fine type can you learn that the Zephyr is really CB-102, the Broadway Limited really CB-304.

Hunter, now a division of Robbins & Myers of Memphis, used to do this. In 193 customers ordered Tuerk Artistic Ceiling Fans by such names as Alum, Agony, Alarm or Advert. Now all Hunters are simply Olde Tymers, but they sell as well as their more exotically named ancestors. Production is 12 times what it was in 1970. Even so, some popular models are backlogged.

"The fast seller this year," says Mitch Bademan of Maurice Electrical Supply, which has sold Hunters for 30 years, "is the plain white model. Two years ago it was brass. People are buying them now for what they do, not just their looks. Some weeks I sell 40 fans, but usually it's closer to 20. Lots of people are buying them for their kitchens."

Other salesmen also have a hard time keeping certain popular models in stock, but they all agree that the Hunter is a great investment in spite of its cost.

"You can take a Hunter made in 1930 and put on blades made in 1979 and they'll fit exactly," declares Bruce Broberg.

Broberg should know. Fans are as much a hobby as a vocation. He's traveled the United States locating authentic designs for brass-plated, cast-iron grills and blade-irons he uses to customize the fans he sells at Interstate Electric Supply in Fairfax. Dressing up a fan with Broberg's grape or palm leaf pattern also dresses up the bill about $100.

Ceiling fans are more than glamorized flyswatters. They can lower utility bills dramatically. Using no more energy than a 150-watt light bulb, they can make a room set for 82 degrees feel like it's 74. They move air, not cool it. But the moving air can cut by 6-8 degrees the need to cool the air being moved.

"It makes you more comfortable because it mixes the hot and cold air and evens the temperature," explains Howard Ross of DOE's Conservation, Agricultural and Engineering Systems Branch. "It's probably no more energy-conscious than any room fan, but anything that allows you to turn off your air conditioner saves energy."

One Florida man claims that since he installed two fans to supplement his air conditioner, his electric bill has dropped 30 percent. Hunter claims that on a hot day an air conditioner may need to run only half as often.

The same principle works to lower winter fuel bills. A ceiling fan pushes down and circulates the warm air that collects near the ceiling. The higher the ceiling, the more a ceiling fan saves on a furnace's energy demands. This may be sone reason why fans are so popular in high-ceilinged old homes being restored.

Turn-of-the-century fans were sized by ceiling height instead of blade length. Hunter's Dragon Fan (pat. 1890) was designed for ceilings 11 to 16 feet high. The ornate dragons, for $1 extra, were left hollow for the wires that lit the incandescent bulbs the dragons appeared to be spitting from their mouths. Ironically, this was one of the few fans with polished brass tubing. Today, brass is still the "Cadillac of the fans," according to Broberg.

Most fixtures were made of iron that was bronzed, but then, as now, there were options. Hunter's early catalogues offered the iron parts finished in plain black or maroon or "for a look in keeping with the most elegant surroundings" nickel plate.

Blades were varnished oak. Buying four instead of two blades meant putting out an extra $2. Ball bearings were also extra: $1.50.

There was no extra charge for the blade adjuster, mighty handy in a smoke-filled parlor or over a table of card-players. By flipping a small lever on the motor you change the pitch of the blades so air goes up instead of down.

Hunter's "Adaptair" blade adjuster is now a $120 option. Blades without the feature are $40- $50, but reputable salesmen give a credit for the difference. You can get the Hunter's Adaptair on Classic fans, as Hunter and Classic parts are interchangeable. Emerson aslo offers the feature as an option, but it's unavailable on most makes. It's standard on Casa Blanca.

Premium blades are still made of nicely-grained wood, usually oak, but most other makers stick to the less expensive simulated-grain blades or painted ones of wood, metal or plastic. Casa Blanca, Classic and Hunter offer blades with stencilling or cane inserts. The extra touch runs about $30- $50.

Light-adapter kits are always optional. They run around $20. They're easy enought for do-it-yourselfers but most sellers will attach them for a nominal fee. The usual globe is schoolhouse vintage. Only Casa Blanca, which tends to the extreme in design, gives a wide selection. Other Casa Blanca kits are wired for four ( $85) or even five ( $110) lights. You choose four frilly glass shades from among seven styles and, maybe, add a larger, usually schoolhouse, globe for the center. Other companies are beginning to offer four- and five-light kits.

Like the old days, a pull chain is the standard switch. If you have a light, there are two chains. If you want more than high and low speeds, you use an optional wall switch that operates like any dimmer switch.

Whether or not to even consider adding a light depends on ceiling height and make and model of fan you choose. Lights cannot be used on low-hung ceiling fans since just the fans and their motors take up 12 or 13 inches. A schoolhouse globe adds about 8 more inches, although the more expensive four- or five-light systems require only 6 inches. Most fans, even without lights, require a 9-foot ceiling. A few need only 8 feet.

Light kits are not usually interchangeable among makes of fans. Many companies offer swag-chain kits so fans can be installed where there is no ceiling wiring.

Fans can be installed where the ceiling is unusually high, simply by using a longer stem mount. Only Casa Blanca's fans require special stem mounts. Other fans need only an extension pole, threat ded at both ends, that most hardware stores can supply.

All ceiling fans require strong support. They must be attached, usually with lag screws, to a ceiling joist. It's not unusual for a fan, even without lights, to weigh 50 pounds. The weight of a fan cannot be judged by the apparent size of the motor.

Less expensive fans often have large, lightweight motor cases with small capacitor motors inside, what Classic Fan dismisses as "Tin Can Fans." Classic and at least one other manufacturer, Hunter, have heavyduty induction motors. Accroding to Classic, the extra weight of solid cast "pancake" cases contributes to "smooth operation, stability and long life expectancy."

It's too soon to tell about a Classic's life expectancy, since the Texas company has been around less than a year, but Hunter, which Classic unabashedly imitates, confidently predicts a fan life of "well over" 40 years.

And well they might. One very satisfied customer has his father-in-law's 75-year-old fan that has been rewired only once and runs like new. That man's from Texas, where 78,000 fans were sold in 1978.

The South, with its verandas and mosquitoes and longer, hotter summers, has traditionally been a better market than the North, even in the lean years of the '40s and '50s when everybody deserted ceiling fans for new-fangled window fans or air conditioners.

No more. The industry is reviving so quickly that some domestic manufacturers have persuaded the National Electrical Manufacturers Association to establish performance standards for residential fans, those under 52 inches (blade length when installed). As of now, all a consumer can look for is a UL stamp of approval, which means the fixture's electrical parts meet minimum standards established for all fans by Underwriters Laboratories, an independent testing lab. NEMA standards will help buyers choose the right size fan for the space it must serve and the air it must move. NEMA will only represent domestic manufacturers, even though many of the lighter weight fans are made abroad.

"Apparently the motors of those made abroad are okay. But many of them still use steel blades," cautions Scott Huff of NEMA. "That's a spinning razor if you reach to stretch your arms."

Scott, whose new job it is to keep track of the industry, reeled off a list of manufacturers, most of which entered the race for fan buyers only within the last year or so.

They're in the right business. As one local salesman, a little amazed, exclaimed, "One of our customers already has seven fans in his house!"

Some stores with glamorous fans, as well as more basic models, are:

Atlantic Electric Supply, 2736 10th St., NE.

Haymarket, 729 8th St., SE.

Interstate Electric Supply, 8435 Lee Highway, Fairfax.

Reed Electric, 1611 Wisconsin Ave., NW.

Maurice Electrical Supply, 1134 11th St., NW.

Simple models can be found at Sears & Roebuck3, Montgomery Ward, Hechingers, and most electrical supply stores throughout the Washington metropolitan area. They also can be amil-ordered through classified advertisements in many home-decorating magazines. CAPTION: Illustration, An "artistic" ceiling fan as advertised in the 1903 Hunter Fan Company catalogue; Picture, Fans help cool Timberlake's restaurant in Washington. By Gina Stevens - The Washington Post