Something is killing my RO/DI system

[Herpervet]

This is long but necessary I think to fully paint the picture. My apologies in advance.

So I have been using a buckeyefieldsupply 100gpd ro/di system for about a year without incident.

Recently called the owner about my di resin as it was changing color and my tds was up.

Ordered replacement catalytic GAC as it was months over-due for replacement as it turns out, prefilter and di resin. Carbon block had at least 6K gallons left.

Replaced the catalytic gac and the di resin. Soaked the gac over night and rinsed the gac very thoroughly according to instructions.

About a 10 days pass without a problem and then di resin is already exhausted and I was not getting anything through the ro membrane either.

The owner of buckey.....is un-available it appears until July so I call Purelyh2o and Brian helps me trouble shoot. He thinks the carbon block is plugged from the catalytic gac.

Also, water pressure is very unstable lately and he thinks that may be the source of most of my problems. So I ordered a booster pump it is on the way.

In the mean time he recommends I replaced the carbon block filter and added fresh di resin and said I could run water through the di only to get some make-up water as I am rapidly approaching a crisis with top-off. He also said I should switch the stages from:

prefilter---->catalytic gac------>carbon block------>ro------->di

to

prefilter------>carbon block------>catalytic gac----->ro-------->di

to keep the gac from clogging the new carbon block. This is the opposite of what the buckeye guy told me but no biggie, reasonable people can disagree sometimes.

So I do all this and get a little water before the ro quits flowing and I figure it's partially plugged and 30 psi just won't cut it any more.

We talk some more and decide to replace the di resin and by-pass the ro for now to get some make-up water and wait on the booster pump.

So I did this. At first the water flowed freely and almost disturbingly fast so I shut it off and let it sit over night until I could check back with Brian and make certain such a fast flow through the carbon stages wouldn't allow chlorine or chloramine through. He tells me that I can slow the flow with a ball valve if I am concerned.

So the next day I crank it up and it's obvious that the flow is already much slower. I don't think too much of this at the time and leave the unit to run......

I got about 20 gallons of water over night and the resin is already turning. TDS went from 2 to 10 over night and the resin is plugged or gummed up in some way as water only trickles out now but runs freely through the first 3 chambers.

So the only conclusion I have at this point is that the catalytic gac is crap since it is the only thing I changed at first other than the di resin. I suspect I am getting chloramine or chlorine into my resin and it has chewed up my resin. Merely sitting in the water over night started degrading the di resin.

I have checked and the ro memberane will not flow at all even at 40psi so I am betting it is shot too since 40 was plenty of pressure for all these months.


What now? I am going to spend an extra 60 bux to over night a complete replacement set of cartriges because now I am only a day or two from a real problem with top-off.

Brian recommends the 75gpd membrane since with the booster pump it will crank out 150 per day anyway and gave some other logical reason why it was a better choice but I can't recall exactly why.

In short: I am Murphy's *****. (good sig line material if it makes it past the filter)

Anyway suggestions or explainations are welcome.

 

[Boomer]

I would agree with your ASSESSMENT that it is the catalytic GAC. The purpose behind catalytic GAC is that it is more efficient than a std carbon block at removing chloramines/chlorines. The std carbon block does still remove them just not as well. I would shoot for a new catalytic GAC, at their cost. His method of switching the two around is self defeating if the catalytic GAC is pouring out fines. Either the GAC block or the DI, RO, RO/DI will still get plugged. He should have left it the way it was, at least then the GAC block would act as a prefilter without ruining everything else inline, where you are now. Common sense should have told him that

 

[Hobster]

Do you have a flush valve on the RO membrane? Have you been flushing it out? What is your tap water TDS before the membrane and TDS after the RO membrane only?(before the DI)

 

[purelyh2o]

I will go ahead and leave the common sense statement alone..

But, The reason that we decided to stay with The Cat as the final carbon is because the block is a fairly unforgiving filter and cloggs fairly quickly given larger particulates. Using the GAC filter as the final stage has been in practice in our systems for quite a few years and has proven successful. The membrane is able to clean itself and has proven in our systems to be able to deal with the exposure to carbon fines without any issue and certainly less issues than we have experienced with the carbon block clogging from the GAC residual. Its just the way we have decided to do things and I pose no insult to anyone who uses a different configuration. we just prefer it this way.

 

[Boomer]

Well, other RO comapnies will disagree . The guy bought another unit/system from a different comany who flattly disagree with you, as I do.

Shoudd be
prefilter---->catalytic gac------>carbon block------>ro------->di

and the there is this

This is the opposite of what the buckeye guy told me

So the vote is 4-1 and you loose No insult posed

 

[purelyh2o]

Umm

Umm

This is not a game.

And Im sorry but the opinion of the other companies are no more valid than mine. Things are done differently and this is the way we do it and it works.

I suppose you would also believe that a carbon block removes chloramines too? I guess my point here is that we do not just put together systems and throw them online . We actually do test them and beta different configurations to make sure they are effective. There are alot of different opinions regarding water filtration and some work some dont. The reason we changed the order in which the filters are placed in the system is due to the fact that we were experiencing the same problem as above and found that simply putting the cat after the block and not before allowed for better flow, longer because the block dd not end up clogging. I have yet to see an issue where the membrane clogged from the exposure to the fine from the cat carbon. Also as far as saying that Other companies disagree, please remember that there a heck of alot of companies that use only GAC filters and not blocks at all before themembrane. These are standard drinking water system configurations that last quite a few years before changing the membrane. We have been doing this for a while and have not steered our customers wrong yet. We back up our products as well so if something were to go wrong we foot the expense to get it resolved.

 

[Herpervet]

Guys,

Just to set the record straight: Bryan has been nothing but helpful.

He went above and beyond the call to help me out and spent a lot of time on the phone troubleshooting the issue.

He is a top notch guy and I highly recommend his company.

Like I said before: Reasonable people can disagree on some things. (good grief look at all the different opinions on reef keeping and plenty of successful tanks that validate every different approach)

 

[Boomer]

Who said this a game ?

Can a carbon block remove chloramines ? Yes it can. Would like to debate the chemistry on the issue ? I would be more than glad to .

C-Blocks are just not as efficient as C-GAC and is the reason behind C-GAC. Any form of GAC or a carbon block will take out chloraimes or chlorine. Chlorine and chloramine removal is a chemical reaction between chlorine or chloramine and the carbon, that yields CO* and chloride ions. Different types of carbon, pore structure and grain size are what controls its rate of removal.


edit;
I see that you edited post . If that works fine for your them fine. It appeard to me you did not do Herpervet very well and is why he was here.

OK Herpervet

 

[Herpervet]

Actually Boomer,

I was only trying to get a better understanding of why my system quit so abruptly. Brian has helped a whole lot and has gone to a lot of trouble to get me the booster pump I need.

I don't think that these discussions need to get nasty.

From what I can see I would gather that either method of cat-gac placement can work and I see the logic in both approaches.

No need to make this a personal and/or professional contest.

 

[Boomer]

I'm not getting nasty or personal Herp, I'm answering the questions at hand.

I'll make no further comments

 

[Herpervet]

I'm cool with that and I do appreciate your opinion.

I just hate to see fights on this forum. There is room for all of us.

thanks,

Pete