Rip, Trust but verify!
I have had guys swear that some control was in such and such position only to find IT WASN"T! Before I achieved my advanced state of enlightenment I had tried to trouble shoot electronic equipment that wasn't even connected to power.
A couple months ago both the hot and cold supply lines to the north side kithen sink froze up. The plumber assured me they NEVER attach pipes to the outside wall and ALWAYS leave room for insulaltion between the outside wall and the pipes. The insulation contractor swore that they always put the insulation between the pipes and the outside wall unless the plumbers didn't leave room in which case they woild leave a section uninsulated to let heat leak out to the pipes to avoid a freeze up.
...and now for the rest of the story... The pipes were clamped securely to the outside wall AND they were insulated on the interior side, keeping the heat from getting to them. Both contractors had done exactly what they said they NEVER DID!
I fixed it, having to contort my 6'2" 245 lb body to wedge myself into the undersink cabinet and work behind the garbage disposal, all the while not thinking kind thoughts regarding the two sub-contractors.
As an optimistic realist I hope for the best but deal with reality. Let us know when you have got some known good data regarding yoiur static water prressure (no flow) and the dynamic pressures measure under various flow conditions. This will allow making decisions from a position of knowlege and not having to just guess at possibilities.
Rather than muse regarding the number of angels dancing on the head of a pin, lets get a magnifier and count the buggers.
[img]/forums/images/icons/smile.gif[/img] Pat [img]/forums/images/icons/smile.gif[/img]