Not only that, but dead off its still going to be in the zipcode of 80psi in the system. When he broke the seal you know it made a lot! of noise. It didnt just hiss out, it blew out and flash froze the immediate vicinity.
If he had stopped there and brought the car to Chris to put the A/C back together, I wouldnt have been making fun of him.
..okay, thats a lie, I still would, but it wouldnt be as funny. Just sad.
But he managed to continue with the delusion that he in fact had the heater core. Im forced to believe that he does not have any mechanical knowledge what-so-ever.
Which is okay! Not everyone can see how mechanical objects interface and just intuitively discern their purpose and the method of repair.
Its also okay to want to learn more.
But at the same time, I wouldnt recommend someone with no prior mechanical background start with a heater core R&R on something that takes hours of labor for an experienced tech to accomplish. At least, not without someone experienced to help them.