Florida ? A space station air purifier was working again Sunday after it shut down at the worst possible time, when company was still visiting and had swollen the on-board crowd to a record 13.

The repair by flight controllers, albeit temporary, came as a great relief to NASA.

Even if the carbon dioxide-removal system had remained broken, shuttle Endeavour would not have had to undock early from the international space station, said flight director Brian Smith. But the system needs to work to support six station residents over the long term, he said.

The machine for cleansing the station atmosphere, on the U.S. side of the sprawling outpost, failed Saturday when it got too hot and tripped a circuit breaker.

Flight controllers managed to get the unit up and running again 8 1/2 hours later in manual mode. That means extra people are needed in Mission Control — six each day — to handle the approximately 50 computer commands that need to be sent up every few hours.

Normally, the system runs automatically. Smith said engineers hope to come up with a software solution soon to have the system back in automatic.