[Lee.]

Hi guys,
I'm a little stuck as I want to polish my water before it goes into the holding tank which then is pumped into my van. I am only a small business so I bought an ro man 450gpd system. I have a 5/7ltr pressure vessel full of resin. The question is will the pressure needed to push the water through the di vessel cause the ppm to rise coming out of the ro? If so what would I need to do? Restrict the exhaust out of the ro?
I would appreciate you comments please

[Dry Clean]

You might get a small amount of back pressure but I can see it being a problem as plenty work this way, personally Iv always run my Ro tank water through the DI on demand as the DI vessel doesn't take up much room in the van.
Does away with RO tds creep and also means I can bypass the resin for jobs where I don't need a zero tds.

[Lee.]

Thanks dry clean, your method I've been using for years and it's the preferred way for me also. I just wanted to use a two man system now and guessed it would be cheaper to send polished water to the holding tank than to buy an extra di resin vessel. TDS creep is something I was concerned with. To illuminate that I put the resin canister in between the holding tank and the van, but for some reason the resin depleated quite quickly and I couldn't get it under 1ppm at any time. So I just gave up and put it back in the van. The back pressure from RO and TDS creep is something that concerns me. Thank you for helping me with that.

[Stoots]

T cut

[Lee.]

Thanks Alan,😂
That's why I've got so many of your customers now😁

[֍Winp®oClean֍]

Thanks dry clean, your method I've been using for years and it's the preferred way for me also. I just wanted to use a two man system now and guessed it would be cheaper to send polished water to the holding tank than to buy an extra di resin vessel. TDS creep is something I was concerned with. To illuminate that I put the resin canister in between the holding tank and the van, but for some reason the resin depleated quite quickly and I couldn't get it under 1ppm at any time. So I just gave up and put it back in the van. The back pressure from RO and TDS creep is something that concerns me. Thank you for helping me with that.

A properly working DI vessel should present no resistance to water flow- particular at lower flow rates. My guess why your TDS rose when you put the vessel between the holding tank and the van is because of the much higher flow then presented to it. The slower the flow through a DI vessel- the more economical the resin service life.

[P @ F]

How much pure per hour comes out of the RO before it hits the DI ?

[Lee.]

Thanks Peavey Wolfgang, that really helps. I have bought some connectors and will make the switch asap.
Thanks again all

[slap bash]

Your water flow from RO to DI will be the same as the DI does not offer resistance and the water needs to do is flow over the beads to work until they are coated with heavy metal residual. Filter and membranes resist flow. A DI is a pressure tank but offers no resistance. It would if your di outlet became blocked but this has never happened before. What surprises me, no one has ever tried to place a pump before an RO and a second after the RO as this should increase flowrate to the DI. I guess I will try it soon.

[Don Kee]

Your water flow from RO to DI will be the same as the DI does not offer resistance and the water needs to do is flow over the beads to work until they are coated with heavy metal residual. Filter and membranes resist flow. A DI is a pressure tank but offers no resistance. It would if your di outlet became blocked but this has never happened before. What surprises me, no one has ever tried to place a pump before an RO and a second after the RO as this should increase flowrate to the DI. I guess I will try it soon.

No it wouldn't, and why would you want to increase the flow through your DI even if you could? You'd just go through resin quicker...