RODI: way too much waste water

[lilrobb]

So I bought a new RO membrane and a matching flow restrictor,
I hooked up the new membrane and changed my DI resin.

Running the unit produces now a LOT of waste water, probably 1 gallon RO to 10+ gallon of waste water.
The flow restrictor is one of the tiny ones that goes inside the pipe and seems to be working.
Reading TDS (before DI):

IN 64
OUT 1 (only running for a few minutes, so probably 0)

However, the resin changed color IMMEDIATELY, even when the entering water was only 1TDS.

So, what could cause the super high waste output, and why does 1TDS water (less than a quart) change an entire DI cartridge to yellow?

Robb

 

[lilrobb]

Thanks, I reseated the membrane but still a high ratio - probably 1:5.
I am debating adding a ballvalve in the wasteline to cause slightly higher backpressure in the unit.

Also - can DI resin go bad?
Only explanation I have for my stuff getting exhausted so quickly.

 

[jennm]

Membranes have a preservative on them. Usually you have to discard the first hour's worth of water, as the TDS is usually in the 200s as the preservative (which is harmless), washes off.

Not sure if that would exhaust your DI resin that quickly, we haven't seen that happen.

Jenn

 

[raisedonnintendo]

It's cold burrrrrrr maby that's why??

 

[tgray3]

Robb, you might want to disconnect the DI and the flush the RO membrane for an hour or 2 without it. As far as the DI resin goes, it may be something in the preservative that caused a color change, I'm just guessing here. I wouldn't worry about the color though as long as your getting zero TDS after it.

 

[raisedonnintendo]

I forget about flushing mine auto flushes. So +1 to that idea. Is yours motorized I here they r less affected by temp then there counterpart

 

[mojo]

I've found that the flow restrictors aren't exact. In fact, I've got two or three on mine, and have even had a John Guest valve on it at one point - just keep cranking the thing down until you see the TDS creep up, then back up a little.

I have about a 5:1 water:waste ratio (yes, 5g RO to 1g effluent), but I run dual membranes and a pressure pump to 85psi. But the key is having more control over the effluent.

 

[lilrobb]

I 'fixed' it today with an extra ball valve in the wasteline. Now a 1:2 ratio, and that's something I can live with.

The super fast exhaustion of the DI still baffles me though.

Good info and thanks for the input guys and gal, haha

 

[mojo]

LilRobb;586234 wrote: I 'fixed' it today with an extra ball valve in the wasteline. Now a 1:2 ratio, and that's something I can live with.

The super fast exhaustion of the DI still baffles me though.

Good info and thanks for the input guys and gal, haha

Keep turning that ball valve! You can do better than 1:2!

 

[swfk44]

catch the discharge water and use it to wash clothes

 

[raisedonnintendo]

Beule

 

[brynbyers]

LilRobb;586234 wrote: I 'fixed' it today with an extra ball valve in the wasteline. Now a 1:2 ratio, and that's something I can live with.

I seem to be having a similar issue, too much waste water (it actually looks like a drinking fountain outside). From what I gather is that due to the colder water running through it, it's harder to push the water through the membrane, as it's denser than warmer water, thus the extra waste.

Your extra ball valve on the waste line...is that acting like "a booster pump to the front end"?

 

[lilrobb]

Yup,

higher backpressure forces more water through the membrane...
If you flush the membrane on a regular absiss there should be no adverse effects...

 

[brynbyers]

Cool. That has got to be cheaper than a booster pump. I already flush the membrane on a regular basis (usually when I turn the water pressure on) so this might work!
And like I needed another reason to go to Home Depot...