RO/DI Help!!!

[oilfieldsafety]

I have a 6 stage "Reef Safe" RO/DI system that recently developed a problem that I haven't been able to solve. When the system has filled the resevoir and the shut off shuts the feed off, the resevoir tank leaks back through the system until it trips the feed water back on. I have changed the shut off valve with a new one from BRS but still have the problem. Any and all feedback appreciated.

[mark]

know with the Aqua-safe there is a check valve. Mine wasn't shutting off, had cleaned then swapped the ASOV to no effect. Changed valve no problems since.

With the Aqua-safe valve is on the blue line between the ASOV and membrane

[oilfieldsafety]

Great drawing!!! The valve that you are talking about is the one that I thought was the problem, I have tried cleaning the old one and have replaced it with a new valve but still have the leak back going on.