Shuttle Crew Gets Phone Call From Bush, Young People : Space: The astronauts also repair a broken toilet and conduct experiments. California device that could help preserve the ozone layer is tested.

Don’t things like this always seem to happen? Just before the Distinguished Guest is due to arrive, the toilet jams.

It was that kind of day aboard the space shuttle Discovery on Friday. The seven members of the international crew were told earlier in the day that President Bush would be making a telephone call to the orbiting spacecraft. Mission Control told them to “comb your hair and smile.”

Then they learned that a lever that flushes Discovery’s toilet was broken. Ground controllers quickly figured out how to use the facility without the lever, and the toilet returned to operation in plenty of time for the President’s call.

“We just called up to wish you well,” said Bush from a White House meeting of the Young Astronauts Council, where he had announced plans to push for a major increase in funding for the National Aeronautics and Space Administration.

The President then turned the microphone over to some of the young people at the meeting. Mostly, they wanted to know what it feels like to be in space.

“It’s great, just floating around,” answered astronaut William F. Readdy, who celebrated his 40th birthday Friday.

Readdy said it is even easier to do some things in space, such as “putting your pants on both legs at the same time.”

As soon as the brief teleconference ended, the astronauts returned to their chores aboard the shuttle. Norman E. Thagard, 48, spent much of the day planting oat seeds so that scientists can study how their roots grow in microgravity.

“I feel like an Iowa farmer,” he said.

One of the experiments on board the craft could have a profound impact on the struggle to preserve the ozone in the Earth’s upper atmosphere. The ozone, which protects the planet from harmful solar radiation, is being eaten away by chlorofluorocarbons used as coolants in everything from household refrigerators to orbiting satellites.

So far, no one has come up with an acceptable substitute for the ozone-depleting chemicals, but tucked into the shuttle’s cargo bay is a revolutionary refrigerator that uses no harmful chemicals and works on an entirely different principle.

The “space thermoacoustic refrigerator,” developed by scientists at the Naval Postgraduate School in Monterey, Calif., operates on sound waves. The device was designed for use in satellites where temperature control is essential, and this is its first test in space.

Physicist Steve Garrett of the Monterey school said he sees no reason why the same technology cannot be used for such things as home refrigerators. Since the first report on the device appeared in The Times several months ago, he has had numerous inquiries from major manufacturers, he said.

The space refrigerator uses “a rock ‘n’ roll loudspeaker” to cause harmless helium gas in an attached cylinder to slosh back and forth, Garrett said. The movement causes the gas molecules to expand and compress, thus picking up heat and passing it along “like a bucket brigade,” he said.

As a result, one end of the cylinder gets hot, and the other cold, and either end can be tapped to produced the desired temperature.

The seven-day mission is set to end Wednesday with a landing at Edwards Air Force Base at 8:06 a.m. PST. The other members of the crew are Ronald J. Grabe, 46, the commander, Stephen S. Oswald, 40, the pilot, David C. Hilmers of NASA, Roberta L. Bondar, 46, of the Canadian Space Agency, and Ulf D. Merbold, 50, a German from the European Space Agency.

During the flight, members of the crew have taken turns wearing a Los Angeles Dodgers cap that belonged to astronaut Manley Lanier Carter. He was to have flown aboard this flight but was killed in a commercial plane crash last year. The cap was described as one of his prized possessions.