By Hades.Tripster 2012-09-05 08:08:38
If you keep impurities below 30% the furnace will never blow up, however, you still get leaks.
Would love to know about pressure handle too, but I always assumed it was for leaks. I never care about it much because in most of the synths I do you can stop a leak and still benefit yourself, or the synth time would just end by trying to prevent a leaking from happening.