The union representing employes of the Washington Hilton Hotel yesterday demanded that the hotel pay full wages while it is closed for repairs in the month of August, following two electrical fires this weekend.

Local 25 of the Hotel and Restaurant Employees Union asked hotel management to continue to pay wages, even though the bulk of the staff is not working. Ron Richardson, executive secretary of the local, said that employes will face hardships if they are asked to subsist on unemployment pay, which will only be a portion of their wages. Hotel management still has not decided whether to pay the employes.

"Just because the Hilton is closed doesn't mean the landlord isn't going to make them pay rent," said Richardson, who pointed out that a housekeeper who regularly receives $261.80 per week would get only $147 on unemployment. Six hundred union members are employed by the Hilton, and Local 25 is planning a signup for unemployment benefits in its K Street office this Friday.

The union wants the Hilton to continue paying health insurance premiums for the workers while the hotel is closed.

Although the Hilton is covered by business interruption insurance from Continental Insurance Co. of New York, according to acting spokesman Burt Hoffman, that insurance will not pay employe wages. Instead, the insurance will reimburse the hotel for lost revenue, according to Hoffman. Between a loss of revenue and other costs, he estimates that the hotel will lose between $2.5 million and $3 million.

"In this case, we don't anticipate losing any confidence in the hotel. We just have to get the word out when we're back in business," Hoffman said. He -- and managers of some competing hotels -- predicted that there would be no permanent bad impressions when the 1,154-room hotel at Connecticut Avenue and T Street NW reopens on Sept. 1.

"It's very unfortunate that they have to close," said Leonard Hickman, of the Hotel Association of D.C., adding that the loss will be blunted because August is traditionally a very slow month for hotel business in Washington.

Managers at other hotels expressed sympathy for the Hilton and told their own stories about housing teen-agers and their chaperones who were attending a Youth Congress '85 convention at the Washington Hilton and were left homeless by the closing. Anthony Stewart-Moore, manager of the Mayflower Hotel, said that his hotel managed to shepherd all the youths to rooms in only 42 minutes. "It's one of the most enjoyable challenges I've ever faced," he said.

All the managers agreed that consumers will soon forget the electrical fires. Paul Astberry, manager of the Watergate, managed a hotel in London that was bombed by the Irish Republican Army, but the customers were soon coming back.

"It is amazing how quickly people forget," he said.