Central Vacuum System Component Confusion

Having to special order parts for construction is always a bit of a gamble- I always seem to run out of something, and have too many of something else when all is said and done. This central vacuum system from Nutone is a little tricky since the guidance on these systems is very sketchy at the advanced level (the install manual isn’t all you need for sure, and even generally helpful online resources aren’t answering all my questions), so I’m using what I know about heat flow, pressure and flow, moisture, and contaminants to customize our system with more immediately available materials!