After cleaning up about half a liter of water that spilled from a coolant line and getting rid of some air bubbles that caused the spill, the two crews installed valves that connect Quest to the station's environmental control system and a computer that will be used to run the airlock's systems. They also tested lines that will be used during future shuttle missions to replenish oxygen and nitrogen supplies, and removed bolt drivers from the airlock's berthing port, which are no longer needed now that the airlock is permanently attached to the station.
The extra time it took to get the coolant line working put the crews about an hour behind schedule, so a planned checkout of the airlock's space walk equipment was put off to another day. Station Commander Yury Usachev and Flight Engineers Jim Voss and Susan Helms were able to try out the airlock's audio communication systems, making the first radio calls to the ground from the airlock and two American space suits.
STS-104 Commander Steve Lindsey and Pilot Charlie Hobaugh fired the shuttle's engines for an hour Sunday night to boost the station to an altitude of 238 by 235 statute miles (383 by 375 kilometers). Mission Specialists Michael Gernhardt, Janet Kavandi and Jim Reilly also worked on equipment and supply transfers between the shuttle and station.
Gernhardt and Reilly made preparations for the second spacewalk of the mission, during which they will help install the first set of the High-Pressure Gas Tanks -- one oxygen tank and one nitrogen tank -- onto the airlock's shell on Tuesday. A third space walk, scheduled for Thursday evening, will see Gernhardt and Reilly use the new airlock for the first time.
The two crews will go to bed at 8:04 a.m., with a wake-up call scheduled for 4:04 p.m.