Water system valves

[Basil Shannon]

We recently had a thread where someone replaced a number of cheap valves in the water system with better quality parts. Can't find it.

My problem:
Our park water pressure here in Two Springs Palm Springs runs 80-90 psi which is great for RO water production. But, at that pressure, somehow the output side of the 5.7 pump gets pressurized from a leaking something and will not turn on. If I install my 40 psi regulator, the pump operates normally.

[Basil Shannon]

We recently had a thread where someone replaced a number of cheap valves in the water system with better quality parts. Can't find it.

My problem:
Our park water pressure here in Two Springs Palm Springs runs 80-90 psi which is great for RO water production. But, at that pressure, somehow the output side of the 5.7 pump gets pressurized from a leaking something and will not turn on. If I install my 40 psi regulator, the pump operates normally.

[EngineerMike]

Basil- You may be thinking about added check valves as the solution. Frank Rouse & I went over the schematics of my 06 trying to find the cross connection that allows this reverse pressure charge & it came to naught. We isolated the problem to internal leakage across the body of bypass valves when the pressure is high enough. When I added RO to the 08, I put in one check valve, then fired the system up w/70psi street pressure. I had back leakage again, couldn't find a cross connect in the schematic, and came to the same conclusion that the schematic is correct (enough) and the leak is again through the body of the cheapo bypass valves. My solution was to add a second check valve (now protected in both directions) to eliminate back pressure on the City/Tank bypass valve from either direction. You can check out the layout @ DRR.

[VAGABONDMAN]

BAsil,

The leaks occur thru the factory valves in the service bay - they have a piece of what looks like surgical tubing on the internal shaft; it works positively in one direction but not the other, as water pressure will collaps the tubing. If you pull one apart, you will see what I mean. The easiest fix is to install the two check valves Mike mentions, or you can replace the valves with the positive ball type offered by Seatech (me) or possible by watts. Home depot has a selection of 1/2" push on watts fittings - not sure about the valves.