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BuckeyeHydro
Sun, 20th Apr 2008, 05:54 PM
So you notice that your tds reading on your DI water is up to 4 ppm, and you decide its time to change for a resin change. You take out the resin you've stored since you bought it 4 months ago, refill the resin cartridge, reinstall the cartridge, turn the system on, and let it run for 3 bed volumes to flush the new resin.

Using your TDS meter you check the DI water and it reads..... 14 ppm. Hmm. What's wrong here?

Clue: we know the resin came out of storage just fine. It's in good shape.

As always, the first masstard with the right answer wins... the admiration of the rest.


Russ
krazykdnb
Sun, 20th Apr 2008, 07:24 PM
If your DI resin is not a color changing resin, then it is hard to tell if it is pristine just by looking at it when removed from storage. If the DI resin was not stored properly, it could have been broken down by carbon dioxide.

Second senario: You didn't pack the DI resin well enough.

Krystal
SABOB
Sun, 20th Apr 2008, 07:35 PM
TDS Meter needs recalibrated
BuckeyeHydro
Sun, 20th Apr 2008, 10:19 PM
2 good thoughts, but neither solved the riddle in this case.
ErikH
Sun, 20th Apr 2008, 10:55 PM
The storage container is dirty!
hobogato
Sun, 20th Apr 2008, 10:57 PM
membrane needs to be flushed out?
BuckeyeHydro
Mon, 21st Apr 2008, 05:50 AM
Not sure what you are thinking re the storage container...

The membrane was flushed - remember we are seeing elevated TDS AFTER the DI
alton
Mon, 21st Apr 2008, 06:43 AM
Okay we give up? I always thought after changing filters and resin you were to run 5 gallons of water before testing and then using?
ErikH
Mon, 21st Apr 2008, 07:39 AM
The storage container for the new water is not clean, so the TDS is elevated due to dirt or some kind of buildup that occured. You said all of this was in storage right?
Texreefer
Mon, 21st Apr 2008, 08:31 AM
maybe the DI resin chamber was packe too tightly with too much resin, causing the water to flow through too fast with not enough contact time
Bill S
Mon, 21st Apr 2008, 11:56 AM
Or the resin canister was mounted horizontally, allowing water to tunnel thru the resin.
RayAllen
Mon, 21st Apr 2008, 12:51 PM
And then........ To many variations of things that can be wrong.
subsailor
Mon, 21st Apr 2008, 01:21 PM
Maybe you didn't wash your hand good before replacing and you got stuff from your hands on it
BIGBIRD123
Mon, 21st Apr 2008, 01:49 PM
didn't turn the flush valve off...
bigmoe21
Mon, 21st Apr 2008, 04:04 PM
what is your unit is not a buckeye unit?
BuckeyeHydro
Mon, 21st Apr 2008, 05:37 PM
The storage container for the new water is not clean, so the TDS is elevated due to dirt or some kind of buildup that occured. You said all of this was in storage right?

Nope - the tds was being tested right from the DI output tube.
BuckeyeHydro
Mon, 21st Apr 2008, 05:39 PM
maybe the DI resin chamber was packe too tightly with too much resin, causing the water to flow through too fast with not enough contact time

I've never run across a case of resin being packed to tightly.
BuckeyeHydro
Mon, 21st Apr 2008, 05:40 PM
Or the resin canister was mounted horizontally, allowing water to tunnel thru the resin.

You're getting warm!
BuckeyeHydro
Mon, 21st Apr 2008, 05:41 PM
Maybe you didn't wash your hand good before replacing and you got stuff from your hands on it

The resin change was done with gloves - its not a contamination issue.
BuckeyeHydro
Mon, 21st Apr 2008, 05:42 PM
didn't turn the flush valve off...


good guess but flush valve is closed and 4:1 waste to permeate ratio was measured.
BuckeyeHydro
Mon, 21st Apr 2008, 05:43 PM
what is your unit is not a buckeye unit?

This is an actual situation from one of our customers - they do have a Buckeye Premium RODI.
Bill S
Mon, 21st Apr 2008, 05:56 PM
OK, the canister was on its side, and there was an easy path for the water above the DI resin, bypassing the resin. But, that doesn't make sense, since all of your canisters are vertical.

Maybe it was missing a seal in the canister?

Or, the DI resin wasn't packed down well enough?
Bill S
Mon, 21st Apr 2008, 05:57 PM
Yeah, that's it - the resin was too loose, allowing water to tunnel through the resin.
Ed
Mon, 21st Apr 2008, 06:11 PM
The DI cartridge was installed upside down?
BuckeyeHydro
Mon, 21st Apr 2008, 06:36 PM
WE HAVE A WINNER!!!!!

Big Ed solved it. With the resin cartridge inserted in the housing upside down, it didn't seal, and water went around the cartridge rather than through it.

Once flipped washer end up, the DI TDS dropped to 0 ppm, and all was good.

Make sure to give Ed a pat on the back next time you see him!

Russ
LoneStar
Mon, 21st Apr 2008, 07:13 PM
Nice one!
Bill S
Mon, 21st Apr 2008, 10:42 PM
Hey - I was close with the "missing a seal".