Originally Posted by stebs
I'll have to build a gauge for the return fittings next spring... you've sparked my curiosity now....
When I got started on a remodel I pressured the system up with water. You've prolly seen my induction rig. It's a three way brass valve with vent and adapters for water and air. I placed a liquid filled gauge on the rig. I build individule manifolds from a tee, gauge and no kink hb.
Cut to the chase, I noticed that when inducing water, the induction gauge read a few pounds higher than the gauge on the manifold. At a point during the pressure build the pressures on the gauges swapped. After twenty and before thirty psi the induction gauge went from being a couple psi higher to a couple of psi lower than the manifold gauge.
Well, FMS, this piqued my curiosity a bit. When the weather forecast was for a hard freeze I blew out the lines and brought the pressure back up using air. Same thing happened only the psi swap was at a different spot on the gauge and the spread was only 2 psi. I even swapped out my gauge and the results were the same. Now I'm hooked and want to find out if there could be a differnce on the return than there is on the filter.
VGB drains were created to eliminate Accidental drownings and eservications due to entrapment or inlet obstruction. If the suction is so great it can turn your body inside out, the return pressure has to be higher than 8-12 psi doesn't it?
When you talk restrictions, the inlet on the pump should be the first bottleneck. The filter is a cleansing chamber and not a real pressure building vessel in my line of thought. At least not like a pressure tank. I may be wrong but without installing a few gauges on a few pools, I'll never know.
Posted via Mobile Device