I'm writing here because after conversation with inspector I didn’t get any conclusion.

There are few things that need to be clarify.

1. How to make procedure qualifications on brazed heat exchangers where you cannot check joints from the inside and which have joints hard to classify (sandwich with different shape [plate and nozzle] braze materials [paste and foil] and thickness [0,35mm; 2mm; and I’m not sure abut nozzle what chose wall thickness or height]).
2. There is appendix 17 that is showing similar case but for welding I was wandering if it can be used in this case.
3. I already make prototypes and they survive over 150bar on burst test :)

Thank you in advance for your reply.