Pipe routing elevation to inlet of vaccum pump

None. The pump will pull a vac on the vessel regardless of the length, or elevation of the hose. The condition of the hose makes all the difference, it has to be completely air tight, but you should have know that one.

I've had the pipe routed under the floor to keep people from tripping on the hoses, I'm hung them from the roof ... didn't matter, the pump worked the same.

Laby

If the line gets down to ground level and raises to pump suction, there is a possibility of condensate getting collected in the suction line. Will the pump capable of sucking this collection or the condensate build up goes higher than the suction ability are subject to pipe lay-out.

Draining this condensate against vacuum is also tricky. Might call water sealed trap.

Condensation does not occur in a vacuum. One of the reasons you pull a vacuum on a vessel is to dry it out. If we find water in our vessel, it sometimes take up to 12 hours to pull a vac, so we are very careful to keep everything as dry as we can.

One of the ways to keep this from happening is to use quick disconnects on your line, this way you can keep your pump running 24/7 and your lines will always be in dry and in a state of vac, this too will help reduce the time it takes to evac a unit.

This is not strictly to the thread, but I would ask for your professional opinion
on this diagram. (which is not mine - credit to the author, "Moose")
It claims to suck a vacuum using water, but I fail to see this.

Using the tumbler trick as an example, (upturned tumbler full of water) I have
difficulty in understanding how this could work. Yes, the water would rise to
the vacuum, but not fall out simultaneously? (energy for nothing?)

As drawn it "seems" to add up, but following through the cycle, from creating
(how?) the start, to the completion of the (on-going?) cycle, (never ending?)
then I fail to understand. Would you confirm or comment please?

I have been working on suction and water energy (periodically) with ideas
of my own and not believed this to be workable before now. Many thanks.

jt.