The water purification system had to be shut down to prevent unintended consequences. If they had accidently cut into one of the tubular pipes while it was running, the ship’s entire water supply would have been pumped out within a matter of several minutes, flooding the compartment. What was needed for this process was a double bypass. First, they cut into the tubes near the top of the wall, attaching elbows and short pipe segments as they went about their construction. As the pipes ran continuously top to bottom in columns, zigzagging their way around the ship, Tom and Brandon only needed to cut into the pipes near their top end. By doing so, they isolated a section of pipes that became self-contained, now separate from the rest and thus created a by-pass. The two men determined an area of six or eight pipes should hold a sufficient amount of water for their purposes in this location and then they would repeat the procedure on the opposite side of the Hab.
In the central corridor on Deck Three, Brandon and Tom would then construct a jury-rigged steam powered electric generator. Once the unit is assembled, a spacewalk is needed so someone can gently peel back one or two thin layers of the sprayed-on insulation from the area directly outside of the critical pipes in question. The spacewalk involves some risk as one side of the Hab is constantly bombarded by sunlight while the other is in the shade, with a 500° temperature difference between the two sides.
If it all works as planned, one set of pipes will transmit steam to the generator. The other set then cools the generator and condenses the steam back into water, to re-circulate it. The real trick will be in not removing too much of the insulation, or the ship will either get too hot or too cold causing the plants on the HP Deck to die. The water on the shaded side must be to replaced with an antifreeze liquid to prevent the pipes from freezing solid and bursting into space.