Area residents seeking relief from the heat have been swamping air-conditioner repair firms with calls to fix broken units and have been buying electric fans and window air conditioning units in such numbers that many retailers say they are sold out.

Six repair firms contacted by The Washington Post reported receiving 80 to 100 calls for repairs a day, while two said they were getting more than 200 calls about broken units each day.

Most repair firms say it is taking them two to three days to service calls.

William R. Whitby, service manager of the Krafft Service Corporation in Alexandria, said he has 17 repairmen working 12 hours a day to respond to two weeks wont of calls, and he is still receiving 80 to 100 cals a day.

"If we get a break in the weather we could clean it up, but we're going into our fourth week of this heat," says Whitby, adding, "We've got to get a break. Working six days a week, the men can't keep this up."

Some customers become frustrated and angry when told they will have to wait for a servicean according to Alfred Alltn, service manager for Andy's Refrigeration and Motor Service Co., Inc., in Northeast.

"They get very unhappy when you tell them they'll have to wait awhile. They say "Well, thank you' and then bang the phone down," said Allen.

Most of the service managers said the high number of failures among the home air-conditioners is caused by improper care and the extremelly hot weather.

Bernard Merton, operations manager of Merton Air Conditioning in Capitol Heights, said "Fifty per cent of the calls we receive are for dirty filters. Most problems are customers oriented. The public isn't educated about how air-conditioners work."

Most problems can be avoided by preventive maintenance according to Stephen Smith service manager for Capital Power-Vac Co., Inc., in Baldensburg.

"We had a cool spring and people expected a cool summer. They felt they didn't need to get them (the systems) checked," says Amith.

Area residents apparently also did not anticipate the need for fans and window air-conditioners that has been generated by this unusually hot summer. Several large retail chains yesterday reported a surge in sales of these units during the past two weeks and said their supplies have dwindled or been exhausted, and will not be replendished this year.

The Hecht Co. store in downtown Washington ran out of window air-conditioners a week ago, having sold about 100 units in the preceding three weeks, according to salesman Tom Rice. Another chain official said most of the Hecht Co.'s local stores have few or no cooling units left.

But customers, like the hot, muggy, polluted air, keep on coming. Rice said that yesterday morning alone about 30 people ventured into Hecht's for air-conditioners and roughly the same number telephoned to see if the store had any in stock.

The Sears Roebuck store in Landover has "had some days when it's been wall-to-wall people all day," said Len Schlosser, a salesman. On Monday, Schlosser added, 60 to 70 customers sought air-conditioners, and the store's stock is now depleted.

Dart Drug central supply has been out of fans since late May, a company official said yesterday. Bill Romine, manager, of the Dart Drug at 1901 Michigan Ave. NE, who sold his last fan 10 days ago, said he cannot remember seeing so many people trying to buy fans at this time of the summer.

Drug Fair's supply of fans has been exhausted for the last two weeks, and Marty Ezrin, a buyer for the chain, said he called about 10 sttores in the chain this week to try to find some unsold fans and had to give up. "I just couldn't find any," he said.

Ironically, while Washington area residents work their telephones and the sidewalks for air-conditioners and fans, many wholesalers and retailers are rejoicing.

"It's a blessing in disguise," said one official at Woodward & Lothrop, which has sold out of fans and run out of air-conditioners several times. "Normally we keep a carryover stock in air-conditioners. This year we won't be."

"We're empty and we'll have to stay empty," said one Hecht Co. official. "You're talking about an industry that gears itself up to produce a conservative number of units based on a conservative year in temperature, so if it happens to be a cool summer they won't take any losses," in unsold units.

Retailers said they have begun to notice new buying patterns, along with the burgeoning sales, with consumers being more energy cost conscious. Customers with central air-conditioning have been buying window units while those with window units have been purchasing fans, according to Charles Huntley, director of community relations for Sears in the Baltimore-Washington area.

Sears salesman Len Schlosser said customers no longer are disdaining high efficiency units that cost up to $30 or $40 more but use less energy than cheaper, comparable units. Many residents of centrally cooled houses have been buying air-conditioners for their bedrooms so they can sleep comfortably after shutting down the central air conditioning system for the night.

Barney Menditch, chairman of the air-conditioning and refrigeration board of the D.C. government, suggested this may not be that energy efficient. He said most people make the mistake of turning their air-conditioners off at night to give them a rest, but that only loads the house with moist air during the night. As a result, one third of the central unit's capacity is used exclusively the next day in removing the moisture from the air.