As an update, initial posted pump test results show <sarcastic surprise!> that the pump is pushing at best 2/3 of the flow Rossiclown claimed.
The initial response from Sockpuppet World and The Faithful is that Rossiclown had another (unknown) pump 'pushing' the PD metering pumps. Of course this is nonsense, and shows that these folks have no idea how a diaphragm PD pump works.
In simple terms for those without pump engineering backgrounds:
Inlet is a Check Valve, such that it only allows flow in on a pull (Suction) stroke, and seats when the pump makes its push (Discharge) stroke.
The diaphragm acts essentially like a piston, just has a funny shape in comparison.
The Outlet is a Check Valve, such that it only allows forward flow on a push stroke (discharge), and seats when the pump makes its reverse stroke for fill, due to the the difference in pressure from the discharge header being higher than the pump displacement chamber.
Fluid Source ==> Inlet Check ==> Diaphragm ==> Outlet check ==> Discharge Header
Low Pressure (Suction created by Diaphragm expansion) ==> Inlet Check Valve open ==> Expanding Chamber =\= Outlet Check Valve Closed (Discharge Header pressure above Chamber Pressure) =\= No flow
No flow =\= Inlet Check Valve shut (Higher chamber side pressure created by Diaphragm compression) =\= Compressing Chamber ==> Outlet Check Valve Open (Chamber Pressure more than Discharge Header pressure ==> flow
Thus, if you tried to have a pressurized suction header in order to 'boost' pump flow in a PD Pump, all you have accomplished is to make the fill cycle easier, and use less pump power to fill the chamber (ie. pump motor load is less on the expansion stroke). Once the pump stroke cycles to compression, given that water is essentially incompressible, the Inlet Check Valve is forced shut (thereby isolating the chamber from the feed header), and then the pump pushes the chamber fluid out the Discharge Check Valve, which is now forced open when chamber pressure exceeds the discharge header pressure. Thus if the discharge header pressure is higher, the pump motor is loaded more as it works a little harder to created the pressure differential. The final point being that in a PD pump, discharge Head is independent of suction Head, and as such only manifests as pump motor loading, not flow rate. And depending on the motor type, this loading may need to be extreme to see any difference in pump cycle rate.
One of the newer arguments from the Faithful is that there was a mythical separate pump which feed the heating units on a bypass of the metering pumps... right... never seen in any photos... never heard of until questions were raised about existing pump capacities... sure...
Anyway pump testing continues to account for all possible modes of operation. So far, posted results are no surprise.
Meanwhile, the Rossiclown continues his New And Improved Ecat! Quackx campaign... I wonder what he will call the next one... Meoowx? Roarx?... Barkx?...??? I pity The Faithful, and suppose that at the end of the day, there is always going to be someone willing to drink the Kool-Aid. Jim Jones would be proud, as would P.T. Barnum.
The development of atomic power, though it could confer unimaginable blessings on mankind, is something that is dreaded by the owners of coal mines and oil wells. (Hazlitt)
What I want to do is to look up C. . . . I call him the Forgotten Man. (Sumner)