Testing Membranes

[wingover]

Hi All,

I got a used sea recovery SRC600 that was pickled for 2 years. I am wondering if I can test the membranes by running the unit or do I need to take it apart? If I get fresh water flow with low PPM does this mean that the water is safe to drink or are there any other test I should be doing?

Thanks for any help

[Tellie]

It's pretty simple really. If you flush the system for about 20-30 minutes without pressure then start the system normally and add the pressure and your PPM readings are good your membranes are good. Two years is a bit long to be pickled without re-pickling but it's not impossble that the membranes will work. Taste is always the best test.

[Bergovoy]

so is smell.. hehehehe


and yea, I am guessing it will be okay...

if you want to test with fresh water, you can... just test the water in and out and the waste... try to keep/measure the amount of waste water by the amount of water produced to measure your rejection rate.

not sure if your systems have variable restrictors but those are very cool and youcan dial in your system.

(I have no experience in desalinators, but lots of experience with salt water aquariums where we need ZERO tds water for mixing salt water)

anyways, good luck, but I think you will be ok

[wingover]

What would be a good cleaner to add and flush the membrans?

[Tellie]

Personally, unless a customer is insistant, do I rarely if ever try to clean membranes. Usually the results are worthless. There is an extremly fine line between a good membrane and one that is clogged beyond repair. The problem is that by the time a membrane is diagnosed as clogged it is usually already to late to save it and expect it to act like normal. But not to discourage an attempt, contact Sea Recovery and get the cleaners from them. Your manual will lay out the procedure for chemically cleaning the membrane.

[PamlicoTraveler]

I have a SR 600 that's on my boat and I have never used it...Pickled 5 years ago, so probably needs new membranes too. I'll be interested to see how much they cost if you do have to get new membranes Wingover...

[matauwhi]

G'day, mate. Ditto on Tellie's instructions to see if the membranes will still produce acceptable quality water. Cheers.

[wingover]

More info:

Membranes are dated 2007 so I might be lucky here. I will run them tonight for 20 min with no pressure and than start slowly going up. I do have 2 water flow guages so I will be able to see both fresh and salt flow.

[PamlicoTraveler]

I will run them tonight for 20 min with no pressure

How do you run them with no pressure?

[Strygaldwir]

Replacing a membrane is not as much a heart break as some of the marine vendors have you think. I believe the major manufacturer of membranes is Dow-Corning. If you have a standard size pressure vessel, Dow-Corning membranes can be had relatively inexpensively. For example, my dealer list replacement membranes for about $450, I purchased a replacement for $180. It worked without a hitch for 2 years before I pickled it. I'll just replace it when I put the watermaker back into service.

[wingover]

Originally Posted by Strygaldwir

Replacing a membrane is not as much a heart break as some of the marine vendors have you think. I believe the major manufacturer of membranes is Dow-Corning. If you have a standard size pressure vessel, Dow-Corning membranes can be had relatively inexpensively. For example, my dealer list replacement membranes for about $450, I purchased a replacement for $180. It worked without a hitch for 2 years before I pickled it. I'll just replace it when I put the watermaker back into service.

I am not sure if the sea recovery housing will take 2.5" x 40" dow memebrane. Some manufacturers build on odd size housing so you can't buy an after market memebrane.

[PamlicoTraveler]

Membranes are dated 2007 so I might be lucky here. I will run them tonight for 20 min with no pressure and than start slowly going up. I do have 2 water flow guages so I will be able to see both fresh and salt flow.

Wingover...How is the test going? I am curious as it might indicate what I am to encounter with mine.

[Bergovoy]

Originally Posted by wingover

I am not sure if the sea recovery housing will take 2.5" x 40" dow memebrane. Some manufacturers build on odd size housing so you can't buy an after market memebrane.

in aquarium use and form the industry folks i have spoken with, I was told that there is only 2 companies in the world that make these membranes... filmtec being one of the biggest...

the difference between different BRANDED membranes are the specs... each and every membrane is tested for rejection rate.. some are spot on, some are a tad low and some a tad higher.

depending on the performance in teh tests, the membranes are BINNED, i.e. placed in different bins to seperate the better from the not so good...

these are then sold to the different 'mfg's of RO systems...

so, in essence, you get what you pay for when you get a name branded RO system, but, not always... reputation is everything...

[Tellie]

Originally Posted by Bergovoy

in aquarium use and form the industry folks i have spoken with, I was told that there is only 2 companies in the world that make these membranes... filmtec being one of the biggest...

the difference between different BRANDED membranes are the specs... each and every membrane is tested for rejection rate.. some are spot on, some are a tad low and some a tad higher.

depending on the performance in teh tests, the membranes are BINNED, i.e. placed in different bins to seperate the better from the not so good...

these are then sold to the different 'mfg's of RO systems...

so, in essence, you get what you pay for when you get a name branded RO system, but, not always... reputation is everything...

Unless things have changed this is correct. You can buy salt water membranes on line for less that look just like the rest. But membranes sealed from the factory have a one year shelf life outside of a watermaker and the cheaper ones are the lowest rejection. Some of these online membranes sit around for a long time before they are shipped out. It is not unusal for even the factory unknowngly to slip out batches of membranes that fail upon start up. Not to say that the cheap ones won't work, they will. But membranes, as high tech as they, are are not perfect. If you buy a cheap membrane ya takes yer chances. Membranes from a reputable watermaker company are more expensive. Sure they are in the business to make a profit and that adds to the price. But when a membrane they sell you fails in a month or so or even at start up, which does happen. If they are reputable and several are, you will be getting a replacement at no charge. By the time you buy the second deal you found on the Internet you'll have already paid what the other guys charge and ya still take yer chances. Oh and please, please, if you do go this route, and it's fine with me, don't call your watermaker manufacturer and tell them what a piece of junk they build in hopes of getting a free membrane from them.

[Bergovoy]

if i recall correctly, membranes are identified with markings on them... so if hyou did try to swap them out with a company, they will know...