RO Membrane Replacement Problems (PICS)

[amahler]

Hello!

I have what I've been told (by Kent Marine) to be a 24 GPD TFC R/O unit (it was given to me, so I wasn't sure and it's not labeled).

Since I don't know the age of the filters, I ordered a new membrane and all new pre-filters. The pre-filters are no problem, but there are differences between the membrane I received and the one I'm replacing. In the end, it "fits", but it just produces a fast stream of unfiltered water from the blue production hose and no waste water. That tells me the membrane isn't right.

Marine Depot says the membrane they sold me is Kent Marine RO compatible and are puzzled by the issues. I even sent them photos of it. They are now saying they think I have an old unit (I don't think so) or some drinking water system (don't think Kent makes a line of those... and that disregards the knowledgeable answer I got from Kent last month about the model) and suggest I just buy a new membrane cannister and restrictor from them.

Aside from not really wanting to replace half the RO to match a membrane I was told would work, their restrictors are 35 GPD despite carrying (and selling me) a 25 GPD membrane... so I'm not sure whether that's even a safe match.

Whatever the case, I've got a membrane I can't seem to use and, until I have answers, I'm not inclined to press for a return. To find this problem, though, I had to try using the membrane which means it's no longer in its seal and will likely be hard to return.

Any thoughts on the differences here? I've included links to the pictures of the new membrane (top) compared to my old one (bottom). They are the same length, but the other differences should be obvious. It fits in the cannister and I can screw it closed... but it definitely does not work.

Thanks!
- Aaron

 

[krap101]

send them a copy of the email and threaten to sue. maybe that'll get them to let you return it

no.. lol. just ask them really nicely and send them a copy of the email

 

[amahler]

Well, they were pretty helpful today and I don't know that they won't take it back. I'm curious, though, about why the membrane won't work and what the differences are. They seem certain it should work in a Kent unit.

Thanks!
- Aaron

 

[steve-s]

Do you have any pics of the unit set up? Could possibley be it's not "wired" correctly.

Cheers
Steve

 

[nguyen27]

I think you have the filtered output and the waste output mix up, that why you got steady flow of the unfiltered coming out instead, switch them and see if that solve the problem, I have same problem like few days ago as I replaced and get lazy to lable which tube go where.

 

[amahler]

I could take some shots of it... but, honestly, it looks like the pictures I see online and I don't know quite what to change in the "wiring". Yellow hose goes in to the bottom left pre-filter, moves to the right pre-filter, out to my booster pump, back through a PSI guage and into the right side of the membrane housing.

Left side of the housing has the typical orange waste hose and blue product hose.

I'm getting the right kind of output with the current membrane and, at my new 100 PSI (vs. 20) with water over 70 degrees, meeting or slightly exceeding the GPD. Granted, I don't know if the water sucks or not - I'll find that out tomorrow.

I found a one-page PDF deep in the bowels of a Google search once that looked to be the original instruction sheet that would have come with it. Everything on there matched up to how I have it configured.

It all seems to boil down to Marine Depot saying "this is a Kent compatible TFC" membrane and it not matching the reality of what I have installed (and working). Nobody seems to know why there is a difference. I have an e-mail in to Kent right now with these same photos, so I hope to hear back from them today, too.

Whatever the case, I likely need to order a membrane that does fit (for sure) today to have it in by the weekend. A couple of other websites that sell membranes DO picture ones that look like what I have in their Kent section (including ones made by Dow, for instance). It might just be that Marine Depot is wrong - but I want to give them the benefit of the doubt.

Thanks!
- aaron

 

[amahler]

Well, the output rate with the original membrane is the correct 4:1 balance of waste to production. The previous owner used it as it came and I've never changed it, so my gut feeling is the output hoses are right.

The thing is that when I use the new membrane, I ONLY get output from the blue hose and nothing from the waste hose. Kent describes that online as the membrane not being seated and, since it causes a bypass, it just blasts out of the production hose. Seems to fit.

- Aaron

 

[nguyen27]

Honestly if the system is old, more than 4-5 years, I do get a new entire system instead, the brandnew 5 stages cost like 100 or less, but just me. The TFC catridge costs close to that.

 

[amahler]

I agree if the membrane is going to cost me anywhere near a new system. Do you have any recommended systems that are cost effective? The Kent ones are kind of a premium and, if the membranes I'm getting are "generic" (as they seem to be from just about all vendors), I'm not sure what justifies the Kent BEING so pricey.

Thanks!
- Aaron

 

[nguyen27]

I'm not sure if you ever use ebay, but few of them here, this one I bought from

http://cgi.ebay.com/ws/eBayISAPI.dll?ViewItem&category=20684&item=4386595396&rd=1

or

http://search.ebay.com/reverse-osmo...QQfsooZ1QQfsopZ1QQftrtZ1QQftrvZ1QQsacatZ20625

I'm still looking for one guy who sell also sell the system, and bundle the 20 replacements catridges for $25 more, which I'm using rite now, honestly Kent is just overated.

 

[nguyen27]

Try this
http://feedback.ebay.com/ws/eBayISAPI.dll?ViewFeedback&userid=aquasafesystems

This guy I bought the system and 20 replacement filters, free shipping on the replacement filters, good deal

 

[steve-s]

I bought mine from Aquasafe, great filter. I would suggest this one if you do get one. Comes with the storage tank and the see through DI cartrige.

http://cgi.ebay.com/ws/eBayISAPI.dll?ViewItem&category=20684&item=4387555692

Cheers
Steve

 

[SirLight1337]

I bought my RO/DI unit from a person on Ebay. 125 GPD with a little 3 gallon storage tank for about 130 bucks. Its supposed to be hooked up to a sink and what not, but i just went to HD and purchased a garden-hose to 1/2 inch fitting and rigged up my own little connection. works fantastic. I think its cheaper to replace the whole unit versus all the filters.

 

[amahler]

Which I might still do since I don't yet have a DI unit and these systems are complete.

Bummer is that I just bought all new filters for about what this cost and now I've got a membrane that I still can't be sure I can use. Kent Marine just told me "push harder", so I'm off to try that. We shall see... (sigh)

Thanks!
- Aaron

 

[amahler]

Well, Kent was right.

Before they even told me to do it, I had inserted the new membrane and pressed it hard against a wall, the floor, etc., until I was literally red in the face. All I could imagine was breaking something (either the RO or me) and decided there is no WAY this will work.

Kent Marine tech guy said "push it HARD". Tried again with no luck. So as a last resort, I put it in and then SMACKED the white nipple of the membrane against a doorframe and - "clunk" - right in place.

Seems to work perfectly now.

I'm letting it run a few hours to clear the stuff the packaging said needed to be flushed. Speaking of which, I also need to install my flush kit.

Anyway - this has me considering all sorts of possibilities. If my next replacement of membranes is going to be pricey, I might buy one of the new systems listed above since it's comparable in cost... or I could just stick with this one and add a DI since I know I can get cheaper membranes to fit if I smack them good and hard to seat them.

Ponder... ponder... always a million choices.

Assuming this one is working and my membrane choices aren't as limited as I thought... do you still suggest a whole new system like those on eBay above or just add a DI?

Thanks!
- Aaron

 

[krap101]

well... if it breaks in llike 2 years or so you'll have a new DI system. id go with the new one. but personally i dont have the money for an ro

 

[amahler]

Your comment there does bring up a question for me: what is there to go wrong on these? You replace the key pieces of them from time to time (filters and membranes) inherently... the rest just seems to be pretty innocuous tubing and framework.

Do they become less functional over time?

Of course the other way of looking at this (and I have thought this before) is that it's a bunch of plastic tubes and gaskets... why does Kent charge $300 for it to begin with? I think we know the answer.

- Aaron

 

[nguyen27]

More like the housing of the RO system will last forever (never say forever!), some time it may just worth the money to replace the whole system because of leaking, or hard to find replacement part now a day.

 

[amahler]

True.

Well, like I said, I'm going to weigh all the options. For instance, if getting just a DI that will work is at all comparable to a new full RO with a higher GPD rating AND integrated DI...

I suspect new systems are frequently cheaper based on the razor blade theory of selling me membranes forever.

You've all given me plenty to think about.

Thanks!
- aaron

 

[amahler]

Tomorrow I'm going to get the water checked pretty thoroughly at the college where I work. We have an Environmental Studies department that has a whole water test lab and, from what I gather, some pretty extensive testing capabilities. The professor who runs that lab is going to meet me there tomorrow at 10 AM so we can figure out as much about my water as possible.

Time permitting, I was hoping to test and compare these sources:

- Straight well water in the room that is feeding the RO

- Water I processed with the old membrane that is standing in a clean trashcan I use for holding water I intend to mix with salt (both for the quality of the old membrane AND for the trashcan to make sure it's safe)

- Water coming out of the new membrane (it's running for a few hours now down the drain to flush the new membrane of packaging solutions, so it will be ready tomorrow to sample straight from the blue hose)

- Water coming out of our kitchen tap (more for our own knowledge than anything since I don't plan to use this tap whatever the case)

What I can say from my own cheap-o tests (Sera and Aquarium Pharmaceuticals kits I own) is that the RO does a decent job on what I can test.

The water from the tap in that room has an almost undectable level of copper while the water from the RO is clear as a bell on the copper test. Our kitchen sink, however, is friggin' brown on the copper test color (but the Pur pitcher we use makes it virtually clear on par with the RO). Obviously, there are copper pipes feeding it. I think the bathroom is older galvanized stuff.

The water from the tap in that room has nitrates in the freshwater 10 ppm range or so. The RO water appears to check out as measurably zero.

The water from the RO measures VERY low (between zero and the first test chart color) on phosphates. I forgot if it was any worse on the tap, but I suspect so to some extent.

What I won't know tonight (but hopefully tomorrow) is TDS, lead or other minerals, whatever else I don't know to look for and probably more accurate versions of much of the same.

I have a handheld digital TDS meter on the way for future use.

Can anyone suggest tests that might be possible tomorrow that I should ask about or focus on? What is especially important for the performance of my RO so I can be comfortable with this being my new water source (sick of buying water in jugs)?

Thanks!
- Aaron