RODI not shutting off

[Curt2199]

Got my water bill and I used 13500 gallons last month. End up finding my rodi stuck on and the waste line just dumping water. The membrane is a couple months old 150gpd as well as the flow restrictor which is an inline 1200ml from brs. Thats the only thing thats changed recently. There is no check valve on it but there never was. The rodi is hooked up to a float valve that is operating normally. I added a needle valve to the waste line to correct the waste ratio and see if it would allow the auto shut off valve to work correctly. Its still not shutting off but I pulled the asov, disassembled and clean, reassembled and confirmed that putting pressure on the pure water side via air is closing off the filtered water side. Does this still sound like a valve issue? Incoming pressure is 65psi and before adding the needle valve, the pressure on the pure side with float valve shut was 25psi.

[shifty51008]

You need around 50psi of pressure to activate the auto shut off valve.

[Spyderturbo007]

I went through this as well. Even after the float closes, it takes mine about 3 or 4 minutes to build up enough pressure to activate the auto shutoff.

[Curt2199]

Ok, so if I adjust my needle valve so that the post membrane pure water psi is 50+, I may be severely affecting the waste to pure ratio, right? could this lead to pre-mature membrane failure? I did order a check valve today as well to rule that out.

[howaboutme]

I had a similar issue installing a new BRS ASOV. They gave me a faulty check valve which means the waste water will not shut off. They need to work together. Once replaced, the thing works prefectly, though it does take about 5 minutes from the time the float valve activates to when the waste stops. Hopefully it's your check valve as that's an easy fix.

[Erock9er]

Did you find out anything else that might have caused it to stick.

[r1racer]

Originally Posted by howaboutme

I had a similar issue installing a new BRS ASOV. They gave me a faulty check valve which means the waste water will not shut off. They need to work together. Once replaced, the thing works prefectly, though it does take about 5 minutes from the time the float valve activates to when the waste stops. Hopefully it's your check valve as that's an easy fix.

This ^^^. I only have on avg 40psi of pressure and as low as 30 and my shutoff works so I doubt that it's the pressure.

[acuario]

If I'm recalling correctly what the instructions said on mine, the higher the psi, the more efficiently it works, something like 98% instead of 90 or 92% if the pressure is lower.

[r1racer]

Originally Posted by acuario

If I'm recalling correctly what the instructions said on mine, the higher the psi, the more efficiently it works, something like 98% instead of 90 or 92% if the pressure is lower.

That's with all systems but using a saddle valve usually limits the pressure to around 30-60psi. The shutoff valve pressure is another story.

[Buckeye Hydro]

Originally Posted by Spyderturbo007

I went through this as well. Even after the float closes, it takes mine about 3 or 4 minutes to build up enough pressure to activate the auto shutoff.

This is sometimes caused by the air trapped in the DI housing.

Russ

[Buckeye Hydro]

Originally Posted by acuario

If I'm recalling correctly what the instructions said on mine, the higher the psi, the more efficiently it works, something like 98% instead of 90 or 92% if the pressure is lower.

This really doesn't have anything to do with the ASOV. You're thinking about the rejection rate on the membrane.

Russ

[Buckeye Hydro]

Originally Posted by r1racer

That's with all systems but using a saddle valve usually limits the pressure to around 30-60psi. The shutoff valve pressure is another story.

Those self-piercing saddles limit FLOW rather than pressure. We generally try to talk people out of using them.

Russ

[Buckeye Hydro]

Originally Posted by Curt2199

Ok, so if I adjust my needle valve so that the post membrane pure water psi is 50+, I may be severely affecting the waste to pure ratio, right? could this lead to pre-mature membrane failure? I did order a check valve today as well to rule that out.

What needle valve?

Are you using a needle valve as an adjustable flow restrictor?

[Midnightt]

Originally Posted by BuckeyeFS

Those self-piercing saddles limit FLOW rather than pressure. We generally try to talk people out of using them.

Russ

I actually installed the self piercing valve first to see what the pressure was and the system showed around 40 psi. I then cut the copper where the whole was, soldered in a tee with a little pipe and a valve. Connected the line to it and my pressure went from 40 psi to 60 psi. Saying that the saddle valves limit FLOW is an understatement.

[Buckeye Hydro]

Yep. Good example. The static pressure before and after the fitting would have been the same, but the dynamic pressure wouldn't be - as you saw.

We've had customers try to use those fittings on a tube feeding a booster pump... bad idea. The flow through that little pierced hole can't keep up with the pump demand.

And if you have hard water, expect that little hole to get smaller over time.

And if you plan on touching or otherwise messing around with the fitting, you might as well put a little pan under it to catch the inevitable drips.

Russ