I wonder who did the work on that puppy to screw things up so badly?
Every few years a maint man finds a pressure relief valve leaking on a big water heater in a school. Ironically it sometimes happens on a Friday and he caps it off to stop the leak and plans on ordering parts on Monday.
The explosion normally happens on Sun when not many people are there.
You see it all the time: someone's working on an espresso machine and doesn't have the part needed at hand. The machine gets reassembled without the part or the part's deactivated. The part is forgotten because the machine
works, and the machine is never made right.
I've also seen many instances of the hi-limit tstat bypassed, which can cause catastrophic failures like this. And guess what? It's usually the most experienced machine techs who do these stupid things. It's not because they've malicious intent or have suddenly gotten stupid; it's because of the backlog of work they have to do.