It looked like a dress rehearsal for the Washington Hilton Hotel staff yesterday, the first day of operation since the hotel closed July 27 after an electrical fire.

The bellmen and the doormen stood very straight, periodically adjusting the gold buttons on their gray uniforms and gazing at the empty doorway. The reservations clerks joked among themselves. The waitresses clustered together catching up on news as they waited for customers.

The problem was that there just weren't enough customers to keep the staff of about 800 busy. As of late afternoon, only 57 people had checked into the 1,100-room hotel.

Jeff Williams, 48, a bellman for 17 years at the hotel, looked at the empty lobby and said, "This is zip. This is zero. This is my first day back in six weeks and I should have stayed home. All I am doing is talking to the guys I haven't seen since July."

Aracely Palomino, 32, has worked as a waitress at the hotel for seven years. She, like most of the hotel employes, did not work while the hotel was closed.

"I enjoyed seeing my little boy at home, but the economics was hard for us," she said. "I am glad to be back. It feels good to put on the uniform but I have gained weight and it fits a little tight. I need the exercise I get on the job."

In his executive office, general manager Bill Edwards Jr. reminisced over the relocation of the 4,000 teen-agers who were staying at the hotel for a religious convention when the explosion took place.

"It cost us $700,000 to get them housed, fed and bused around town," Edwards said. "It cost $10,000 just to equip each one with a flashlight so they could see to pack their suitcases. But we didn't have one sprained ankle, not one injury with all those kids. When we let them back into get their clothes, I remember one kid coming down the darkened stairway with a bag in each hand, a little squeeze flashlight we gave them in his mouth and wearing a T-shirt that said, 'I am the light of the world.' "

Edwards said it cost about $3 million to install new switching boards plus $2.8 million in renovation costs and lost revenue. The hotel has insurance, he said.

Edwards, who normally lives in the hotel with his wife and three children, said the six weeks the hotel was dark was "like a twilight zone. It reminded me of an aircraft carrier dead in the water with nothing working. It was eerie."

Edwards said the last two weeks have been devoted to replacing dead plants, washing every wall and window, changing all the linen, scrubbing the bathrooms and deep-cleaning the carpets. "We had to clean every inch of the building," he said. "There is a lot of dust after being closed for more than a month."

Among the few hotel guests who showed up yesterday was Sam Rosenberg of Chicago, who almost didn't make it to the hotel.

He said that when he arrived at the airport, the cabdrivers told him the hotel was closed because of a fire.

"We made our reservations two months ago and we didn't know anything about a fire," Rosenberg said as he headed out to explore Washington on his first visit to the city. "Fortunately someone at the airport knew the place was open."