Water Maker

[Seaglory]

Has anyone had any good experiences/outcomes in making their own water maker for their boat?
I am looking to install a water maker on our 52 President but the costs to buy are very high for something that appears to be half decent, so was wondering if this is something we can make ourselves. Any input and or advise would be apricated.

 

[Mambo42]

I have a watermaker onboard and am very happy with it. I don't know what the quality of the shore water is in the Australia, but here in the Med the shore water quality is pretty bad. A lot of calcium, sometimes even plain dirt and that then goes into the tanks. Results are that everything clogs up with calcium, which is a lot of work to clean again.
Having a water maker means no calcium and that is the best you can do for your equipment, saves a lot of maintenance.
Also, when you spend a lot of time on the water and don't want to go into port all the time to get water, then a water maker is absolutely perfect. In some ports in Europe they already charge 50 to 60 euro to top of your water tanks. Perhaps in Australia that is not the case and then you just have to ask yourself how you use the boat. We spend a lot of time on the water, hardly come into a marina, so for us a watermaker makes a lot of sense. But if you come back into the marina every single night or every other night and the water quality is good in that marina, then maybe you won't need it.
And don't forget that running a water maker requires a lot of electricity. The low pressure pump is usually not the problem, but the high pressure pump does use a lot of electricity (1800 W at 220 V in my case). In any case I would not go for a 12 V watermaker, they are not that good. Nice for very small quantities, but not for large quantities. Mine makes 140 ltrs per hour and my water tanks are 1200 ltrs.

 

[mvweebles]

This topic has come up a couple times, mostly on CruisersForum (sail oriented sister to this trawler forum). My recollection is the folks who have done it generally find there are no savings to be had when it's all done. But the answer may be different in Australia - there are a few watermaler builders in the US so perhaps the competitive landscape and resulting pricing is different.

Peter

 

[Serene]

Cheapest systems I have seen in Australia are the BYO Karcher pump types. See here; Buy Now | Water Makers Australia

I have no affiliation and don't own one, but have been doing my own research and this what I have found from AUD$2,937

Also for Mambo42 town water quality in QLD is generally very good and in most places free to fill your tanks at public wharves.

 

[Serene]

And the required Karcher K4 Compact unit is < AUD$450.

 

[Don L]

I looked at building my own, but when the parts got to within $500 of buying one and still needed hoses I stopped.

People that do build them seem to make a weird small one and I have never read a story of them bragging about how long it lasted and water it made.

There are a lot of price levels of WMS

 

[TBill36]

The principles of operation are pretty simple. Push water through a membrane to remove salts and other contaminants. It takes about 800 psi to do it. So now you need pumps, membranes, housing for the membranes, hoses, a flow meters, and valves. The most expensive part is the 800+ psi pump as the salt water is corrosive and you need one with Titanium or very high-grade stainless internals.
There was a manufacturer years ago that made inexpensive watermakers using off the shelf components along with a pressure washer pump. He claimed you could get more than year out of the pump and then would just replace it with a new one. You used to be able to get one for less than $100 off Amazon. Pretty sure you can buy the rest of the components on-line also. High pressue hoses are not inexpensive either so placement of high-pressure components is important.
I've mentioned in previous threads that there is no need for circuit boards, which you will find in most water makers on the market today. It adds to automation but is a source of failure.

 

[ksanders]

Yes, you could build your own, by sourcing the components used by the several companies that package those components into no frills systems.

How much money would you save?? That is the question. Probably not as much as you think, and buying a unit from one of those suppliers would avoid the time and hassle to source all the parts and pieces.

The big components are...

Low Pressure Pump.
20 and 5 micron filters
High pressure pump
Membrane(s) and housings.
Control panel (this just puts the switcvhes and valves in a single location to operate the unit.)

The connections to the input of the high pressure pump are low pressure fittings. Choose what you are comfortable with.

The output of the high pressure pump is of course high pressure to the membrane housing

From the membrane housing to the brine discharge you also have a high pressure line, and you need a high pressure valve and a pressure gauge to control the back pressure.

On the product water side of the membrane you will need a three way non blocking valve, and a flowmeter, and a tds meter would also be handy.

The system I bought originally was from Rich over at Cruise RO. Rich has engineered a pretty good system and in my opinion provides excellent support for technically minded people. For those who tend to be a bit challenged, he might be a bit overwhelming.

That purchase was over a decade ago now. Today my watermaker has been replaced over time as things wore out, one piece at a time. The only original part left is the control panel with three way valve and flowmeter. But... while I was learning his help was invaluable, and my watermaker has years of every day use.

 

[Marco Flamingo]

Now why doesn't some enterprising TF member come up with a solution? We are all heating up water to cool our engines and transmissions. But then we just dump it overboard with the exhaust. Separate a little bit of it off through an exhaust water jacket where it heats further, boils, and the distillate is then condensed by the other part of the raw water. Drip, drip, drip while you motor. Sterilized distilled water from an exhaust manifold attachment.

I have too many other projects right now.

 

[tiltrider1]

Water makers are a collection of several simple tasks. The automation of several of these tasks is expensive. So, the more manual you make a water maker the cheaper the unit is to build. The question is how much inconvenience are you willing to put up with.

25 years ago I built a simple water maker knowing I would only be using it a few times a year. It cost me half of what a store bought unit would cost. However, it could not test water for quality, I had to route the water into a 5 gallon bucket where I tested the water with a salinity probe before rerouting to my tanks. Once I was done making water, I had to make an additional 5 gallons that was routed to my 5 gallon bucket that I used to pickle my water maker and clean out my high pressure pump.

My real savings was by not automating these two expensive operations. While this unit was half the price it was a large pain to use and I used it maybe 5 times for real.

Was it worth it? Yes, for me because I had no money in those days. Now, I have a fully automatic unit that I use 5 times a year but I have more money now.

 

[wfleenor]

I built my own, but I have a PhD in Environmental Engineering and Water Resources. I don't think there is a lot of money to be saved, even if you settle for a basic system that you have to manually operate. If you are also into programming you can automate it as well but have even less savings with electric valves and selenoids.

 

[Don L]

I built my own, but I have a PhD in Environmental Engineering and Water Resources.

that's great I guess

most can do after sleeping at a Holiday Inn Express

 

[Mischief Managed]

I installed a Solarmaax 12V DC water maker this past Summer. It uses a Clark pump to get the high pressure for the membranes and its incredibly energy efficient. I use < 8 Wh to make a gallon of water (it draws 6.5 amps @12V and makes 9GPH) It;s also very quiet. I modified it a bit so that it has a built in TDS meter. I've only been using it for a few months, but it's great so far. I think I paid $6300 for it.