Well, YOU just wasted an hour of my time!

YIKES! Why in the world didn't they incorporate the operation of all the ventilation valves and blowers into the simulator?
Note that you need a chart to read the table of operating conditions and note that in typical military fashion, the key table, which must be understood first, comes after the otherwise incomprehensible table of operating conditions.
Imagine! A way to kill your whole crew not needing to involve enemy escorts and wasteful use of depth charges and naval artillery shells!