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There is a great thread on this somewhere, adn I do believe the comments on this are outdated.

I have absolutely no problem with making your own WM - if you have a large generator or can put it on your main. Not a great idea otherwise. You may also have some difficulty with getting a wm small enough on your own as most of the home models (IIRC) are 20gph minimum. Nice for a guy like me with a family, not a furry wombat.
 

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Watermakers are easy to make but home-made ones are not necessarily that inexpensive. The cost is in the membrane and also a decent stainless high-pressure pump.

But the mechanics are simple and if you have a friendly engineer who can spin up some of the bits for you, a decent watermaker can be had for a lot less money than the commercially available ones.

There are, I think, several websites that will provide the how-to basics
 

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TDW,
have a look at Citor. They are in WA. There will be a sales rep in NSW. I have a 90L/hr model - uses a davey pump and filters you can buy anywhere.

Gooday Oma, how are you.
We are flying over soon to WGTN soon. Hope the weather is summery.
 

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We are flying over soon to WGTN soon. Hope the weather is summery.
Why would you want to do that?? Come to Auckland instead.

BTW I'm good thanks, how are you? And seriously if you are ever heading to Auckland give me a heads-up.
 

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Why would you want to do that?? Come to Auckland instead.

BTW I'm good thanks, how are you? And seriously if you are ever heading to Auckland give me a heads-up.
Thanks Oma,
Family stuff and lashed to the timetable. I would really have enjoyed catching up. Next trip may be in 20 months time after a pacific loop. [On the plotting and planning list)

Same for you - If over to sth qld, give us a call.
cheers
 

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TDW,
have a look at Citor. They are in WA. There will be a sales rep in NSW. I have a 90L/hr model - uses a davey pump and filters you can buy anywhere.

Gooday Oma, how are you.
We are flying over soon to WGTN soon. Hope the weather is summery.
I will mate, thanks. btw there's an interestin article in this months Cruising Helmsman. (Thats an Oz publication for you non Aussies.)

Dog, I agree re the Sea Panel but thanks for the heads up NorseaRaydor.
 

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Well, I personally have seen that there is a price difference - but it is not massive unless comparing against a Spectra or other 12v, high end model. I have always felt the big positives are that you can make a LOT of water quickly, and if it breaks, YOU know how to fix it. Go look at a Spectra to get a feel for what I am saying.

The negatives are that it is labor intensive, it is much larger than the typical commercially available units, and it may make too much water for you. The rule of thumb I have always considered is that you want to run your watermaker everyday or every other day to keep them membrand nice. WHen you start pushing off to a week+ between runs, you may have a problem with junk building up on the membrane and a premature death.

Note: Dad has a watermaker, not me. His is the SPectra. Nice unit, totally automated, and if that appeals to you and money is not an object, it is a good choice and good product. It is also the most efficient. I am either going to purchase a unit that is of the homemade variety (go here: Aquamarine, Inc - Home as I have seen on eof their products and that is all they have done) or I am going to make my own. I can use the large water cap and I personally want something I can repair and diagnose on my own. This does not appeal to everyone though.

Brian

PS You need a generator (unless you are really creative and can run it off your main and have the power to do so). I am not sure a 'Honda' would push it. If you do not have one, take it off your list.
 

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I am just wondering how often you have to replace the filters on a watermaker.
That depends on how much you use it and how clean the water is where you use it.
 

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If you're collecting condensate from a clean surface the water is perfectly distilled, which does make it taste a bit funny though as even RO water has quite a bit of minerals and other junk in it.

I'd quite like to build a small flash evaporator to use waste heat from the engine/generator or some type of solar still. With a decent vacuum you could make water at about 65º and with a bit of refinement get quite a bit out of it.
 

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We have a solar array (2 120-watt panels ) and we plan to add a wind generator. The array by itself has met all our electrical needs keeping our 700 AH battery bank fully charged. But admittedly we don't have any really heavy draws, just the refrigerator, lights, fans and electronics. With the wind generator I was assuming that we could handle a watermaker (Spectra 150 running an hour or two a day) as well. But, there seems to be a consensus on this thread that you need a genset tor un a watermaker so what am I missing?
 

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We have a solar array (2 120-watt panels ) and we plan to add a wind generator. The array by itself has met all our electrical needs keeping our 700 AH battery bank fully charged. But admittedly we don't have any really heavy draws, just the refrigerator, lights, fans and electronics. With the wind generator I was assuming that we could handle a watermaker (Spectra 150 running an hour or two a day) as well. But, there seems to be a consensus on this thread that you need a genset tor un a watermaker so what am I missing?
No, you don't need a genset to run an RO watermaker, provided it is a relatively small unit. When setting up a watermaker, there will be a few things you will want to do that the watermaker manufacturer may or may not tell you.

First, you want the watermaker output to have a dedicated water tank. This is for a couple reasons. First, if the RO membrane fails, you aren't mixing salt water with the potable water in the other tanks. Second, it gives you a source of chlorine free water to backflush the RO membrane. Chlorine will destroy an RO membrane.

Second, you want to have some way to transfer water from this tank to the regular water tanks on your boat, but have a check valve so that water only goes from this tank-see above for why. :D

Third, you want to size the watermaker so that you don't necessarily have to run it every day...but more like every third or fourth day. This reduces the amount of water used to backflush the RO membrane percentage wise, but keeps the watermaker operating regularly enough that pickling the membrane isn't necessary.

Fourth, remember, you don't want to run an RO watermaker in the harbor. Bacteria and petroleum wastes are fairly common in the harbor and both will damage the RO membrane. An RO watermaker should only be run in clean seawater-harbors and populated areas rarely qualify for this.
 
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What about condesate watermakers? Not old steam water makers, but machines that chill air below the dew point to pull its moisture. Just a representative of the COTS products.

It does not have nearly the per minute output, but it can steadily generate water and can be encorporated into a AC or refidgeration system.
This is not for a boat, You can not have a device drawing 500W all day to produce 7 gal of water daily.
You will burn almost as much fuel in your generator as you will produce water.:laugher.
 

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Post I replied to was removed, still learning. how do I remove the answer once a post is removed?
I'm not sure. I didn't delete anything. But this thread was 10 years old so sometimes weird things can happen. We have had forum software upgrades in that time.

Maybe start a new thread and we can get that rolling? 🙂🙂🙂


Mark.
 
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