ROSI Setup Problems

[sharkodile]

Hoping you can help out a newbie, I am setting up my first tank and bought a 200 GPD RODI from BRS. When I set it up I noted that outflow was low and that my waste ratio was horrible. The pressure gauge on the RODI unit was showing about 30 PSI, which I understand to be low for RODI function, so I purchased an Aquatec 8800 Booster Pump Kit and set it up today. However, it hasn't improved function: when it's running, pressure is around 38 PSI and waste : product ratio is over 16:1 (about 3 GPH of RODI for 50 GPH of waste). TDS on input is 1-2 (surprisingly low even for NYC water), output is 0.

I attach an annotated photo of my setup, any hints on what's wrong?

Thanks for any help and a happy new year to all.

Edit: Hah, subject typo on my first post! Way to get started!

 

[The_Paradox]

Is your pump adjustable? 38psi is still really low. If you get the pressure up and you are still >5:1 I would put a shutoff valve on the waste line to increase back pressure.

 

[Gtinnel]

Taking some pictures from the top of the unit may be beneficial. If your pump is working it should be running at a higher psi, unless there is an issue with your flow restrictor.

 

[fishyjoes]

You should really contact BRS for help since you got it from them and it's a recent purchase. I've done so in the past and they were very responsive.

 

[The_Paradox]

Are those dual sediment filters? If so that first one looks pretty packed with iron.

 

[sharkodile]

Thanks all for your help. It was total newbie user error, the flush valve was open, closing it got the ratio down and let the pump build pressure to 80 psi.

 

[Buckeye Hydro]

Couple additional comments for you:
**With your low New York feedwater TDS, that implies you also have very low Total Hardness - so you are among the few where it makes sense to plumb two membranes in series.

**Ideally you should move your pump so it is AFTER your two prefilters.

**Your sediment filter looks very dirty (does not look like an iron issue).

** Do you have chloramine in your tap water?

 

[sharkodile]

Thanks, I really appreciate the reply. I'll look into replumbing it. Honestly at this moment the system as a whole is a black box to me, so I'll also look to understand it better as a set of connected components. Do you have anything to share on why the pump is better located later in the process?

Re: sediment, I'm not sure why that would be, my only guess is that the water is fed from a line which we don't use often and which is low in the house (basement slop sink) so there was some startup gunk in the pipes (I also had a plumber install the 1/4" adapter and maybe there was some soldering residue earlier).

Re: chloramine - I think not; I can't find any reference which indicates that NYC municipal water is treated with chloramine, and the quality report doesn't mention chloramine.

If you have any further tips or references, I'm thirsty to learn. Thanks again.

 

[Buckeye Hydro]

Looked at your water quality report - yes - chlorine only.

The weakest component on your entire system, in terms of ability to withstand high pressure, are your clear housings. By putting the pump AFTER the sediment and carbon block, you avoid exposing those housings to the elevated pump pressure. Most of that pumped pressure goes out the concentrate tube to the drain, so the DI housing is never exposed to high pressure.

Russ