DIY Watermaker Component Search

[foggysail]

I threw down the gaunlet, one that may come back to hit me on the head but I plan to build or attempt to build a water maker. My initial plan is to use a Wanner D10 pump which is over kill at 8 gal/miinute but I understand that it does not have the vibration of a Cat pump.... but at this point in my search, who knows.

The next thing that I am having trouble getting source and price info on is the pressure tubes, 2.5x40 such as those manufactured by A&M Composits. Yes, I understand that fiberglass is preferred so that is my goal. But even without finding options for pressure vessels, I would like if possible to find a pair with 3/8" fittings rather than 1/4" that I read are used. My hope is to reduce back pressure.

Well, this post is my first attempt to get some information from others who travelled this path before me.

A sincere thanks to all who respond with parts info, suggestions-- positive or negative.

Foggy

[osirissail]

Individual parts are always available from some of the R.O. Watermaker Manufacturers. Also they sell "kits" (a.k.a. modular systems) of all the parts and you assemble them in your boat positioned as room allows. Trying to source everything from scratch is possible but why try to re-invent the wheel? Especially since you will be working with pumps that put out 800 psi of sea water through pipes and hoses into the R.O. membrane canisters. Of course, there is always the "challenge" of seeing if you can do it all yourself - so good luck.

[Stillraining]

Orinsails advice is good..

But I'm a tinkerer...a pump is a pump and pressure is pressure...I have hydraulic hoses built all the time that have to withstand 3500 psi..never had one part on me premature yet...Any commercial hose shop can build you a quality hose...expect to pay about 70 bucks for one 5 to 6 feet long with aeroquip fittings or equivalent.

I have a Cat pump on my 4 GPM 3500 PSI pressure washer...I plan on using it and replace the pressure washer with new...no sense throwing out a great pump that has lost a bit of its Um-Pah .

Honestly i do not know of the vibration you speak of with the cat pumps they run so slow really it would seem hard to imaging much at all....My washer is gas powered so there is plenty of vibration form the engine, so impossible to tell what the pump is doing.

Great pumps though...Mine is over 20 years old and still purs like.........well a cat..

CharlieCobra will testify to that.

[muskoka]

WaterAnywhere

2.5" dia. x 40" FRP Membrane Housing $405.
2.5" dia. x 40" Filmtec SW Membrane, 700 GPD $187.50
In & Out digital display TDS Tester $29.00

I ordered the above pressure vessel and it was delivered to Hong Kong in about 1 week. Very happy with the service.

Now, can anyone supply some prices & links for suitable pumps? I've been recommended a CAT 247.

[osirissail]

One thing a think is missing from the suggestions is the consideration that salt water is going to be pumped through the system - not fresh water. That makes a world of difference when it comes to wear and tear on pumps and other parts. If you look you will see that a lot of the R.O. units are using Titanium pumps or some similar metal. And also the discharge is highly concentrated "brine" salt water which is put through a high pressure regulator.
- - Considering the extra-ordinary high retail prices of R.O. machines these days, IMHO, inflated by market demand, assembling your own is a worthwhile project. Just be sure to use components that are proven to hold up in the ocean environment.

[muskoka]

Originally Posted by osirissail

...a lot of the R.O. units are using Titanium pumps or some similar metal. And also the discharge is highly concentrated "brine" salt water which is put through a high pressure regulator.
...

I've been recommended a Bronze Cat 247. I've heard Titanium is great (but very costly) and Stainless is actually less desirable than bronze. The reality is that I don't want a 20 year pump - I want something that will work fine for 8-10 years. So, in that context I plan to go with a good quality bronze pump.

Any suggestions on price / suppliers / options for this unit?

[Stillraining]

Woops!... I posted my pump as 3500 PSI...its 1500 I believe....still way more then needed for a WM so if its even down by 20% its till plenty.