RO/DI auto shutoff troubleshooting

[markus902]

Hi Folks,

I have been running my SpectraPure 4-stage RO/DI for a while with an auto shutoff valve for a while now. It was working well for a year but I recently had to move the system. I tripple-checked that I have plumbed in the shutoff valve correctly (see scheme below), but no matter what I tried it does not seem to activate. When I shut off the manual valve at the end, water keeps flowing out the waste water line. The system is running on a booster pump (60 psi), so low input pressure should not be the issue. Has anybody an idea why this is not working?

2 suspicions I have:

1. Defective Membrane
2. Bubble In the 4th stage that I can't get out

Faucet --> High Pressure In ASOV --> High Pressure Out ASOV --> 2 First stages --> Membrane --> RO Water out --> 4th stage --> Check valve --> Low Pressure In ASOV --> Low Pressure Out ASOV --> Manual Shutoff valve to tank

Thanks in advance!

 

[Reefing Madness]

 

[StickyThwomp]

Definitely not an expert, but I just troubleshooted the same thing in my setup.

Replaced the asov and it appeared to fix it. Came back again later and then appeared to be due to high input pressure and not enough flow limitation on the concentrate line (mines adjustable, and I had it at 4:1, but that didn't seem enough with two RO membranes?). Working fine now as far as I can tell.

That said, a busted asov or missing check valve after the permeate output seem to be the more common causes.

 

[theMeat]

It takes a minute or few for the asov to shut