I have done that too, caught my maze3 on fire because it was leaking like crazy.Then I blew it out.
Propane tanks can explode...if you heat them up so the liquid expands past the pressure rating of the tank.Big differance there, as any tank will do that.
Punisher was unsoldering a joint and forgot to empty the system
I just did it on purpose.By the way most pinhole leaks, make a flame the size of a lighter if they are lit.