watermaker

S

Shadowcruzr

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Looking for recommendations for a watermaker for a 1976 Hatteras 48 LRC making a summer run through the Bahamas and Caribbean.
2 adults onboard, lots of washdowns and occasional laundry. Owner is a clean freak. His nickname is Capt Swiffer.
 
What's the budget? How many gallons per hour do you require? 12v, 24v, or 110v?

There's DIY (some of our RO's have built their own)
Katadyn
Spectra
SK Watermakers
 
and sea recovery.

what size WM really depends on how they use the boat. if they cruise a lot, I'm guessing they do not run the genny full time so

1)- DC model: chances are this is a 32V boat so unless they have a 12vv or 24v bank (inverter bank maybe) big enough to handle a WM, DC is probably out.

2)- AC model: should be large enough to make enough water in whatever amount of time they usually run the genny each day. ex... if they run the genny 4 hours a day to recharge, then the WM need to make enough water in that time frame. if they use 100USG a day then something about 25GPH woudl be good.

next question is to know how much attention do they want to pay to the unit. Manually controlled units are cheaper and more simple but may require more attention. for many owner operated boats, an all automatic electronic unit makes sense... it will set and adjust pressure, monitor ouput, even do an automatic fresh water flush every 5 to 6 days.

on the downside, they cost more and are a lot more complex... loose the fancy electronic touchsreen and you're DIW.

we have a 900GPD Sea Recovery on Charmer which works pretty well. I had to replace the touchscreen control board under warranty after a year or so but where able to get in within a couple of days. otherwise, it's been fine. it's fully automatic. my only gripe is that the display doesn't tell you when the last Fresh Water Flush was done, only the time to the next one... so you have to trust the software that it was done or do it an extra one manually... minor gripe...
 
For a trouble free set it and almost forget it if your looking for a DC powered unit the Spectra wins hands down.
At 12VDC my unit uses 1ah for every gallon of potable water produced. Take a look or Google "Spectra watermaker" they may make you a custom 32 volt model. They have AC powered units, self contained 12 & 24VDC suitcase models. Make sure you get one with the MPC5000 controller.
Bill
 
We have spoken with a number of folks with water makers in the Bahamas. Some have complained about 12v models, and it didn't matter who's they were. Sailboaters that can live on 10 gallons a day are happy with DC units and many don't even check their tds levels. Most folks requiring higher levels of output are generally happier with AC units. Review a few set ups for HP at the AC level, and then think about the current required to drive those HP numbers with a DC unit.
Power boaters as described above would be intolerant of the level of output the DC units provide. It's all in the HP. It takes HP to push water through the membranes at a recovery rate. If you are going to need so much DC bank capacity and will wind up running the genny regardless, why bother with a dc unit. BTW the cabling for a DC unit is much more critical and expensive due to the required guage. A DC unit pulling 25 amps is going to require very heavy guage wires to keep the voltage drop down. And that stuff is expensive compared to what it takes at the AC level and 220v.
Output claims vary, and one has to read the specs carefully before the purchase. It would also help to know the salinity and temperature of the areas being cruised. Buyer beware...
For example, we were able to get about 8gph at 840psi and 213 ppm tds by the Las Olas bridge in Fl., but in Lucaya, we make water at roughly 320ppm and 880psi at 7 gph. This with a 220v pump into a couple of 22 inch membranes. We know the DC powered unit into the same membranes did not perform as well.
 
Dan just called me a "sailboater", I think. :-)

We get along fine with Bill's old 12v system. But yes, our boat is unique to say the least. I do run it quite a bit when charging up the batteries with the genny, but we can also run it underway. When you've only got two little Honda 50s putting out about 6-8 amps each, such a system is about all that's supported. We also bathe daily (I can't stand not to) and use all the water we want. So depending on the needs of Paul's clients, a 12 or 24v system might work, but might be on the low-side of output needs. Dan, I know you had problems with your old 12v, but Katadyn makes some darn good units. However, Paul's got some real research to do (which he's obviously starting on). Pascal, I forgot about Sea Recovery, so thanks for putting that in. Wow, 900GPD? That's some serious output!
 
The Spectra will produce up to 150 gallons a day. That is the unit I use. Spectra has a model sepecifically for the waters in the Bahamas. I chose a unit for all waters. If my electronic controller fails the system can be operated manually. The next model up is double the capacity. Now 900GHD is a real machine Pascal and if their going to run the generator for shorter periods of time a high output AC unit may be the way to go. Considering Paul is talking about a 48DC I can't see the water capacity being much more than double what we need worst case. I assume the boat has water tanks I reduced the size of my tanks to make room for the house and thruster battery banks. Every situation will be custom and a balance between what is best for the individual boat's use. I wanted total off the grid operation with my boat. But that is why I installed a fairly robust solar system and I can now add wind power generation if needed most devices on my boat are DC. I didn't want to have to rely on a generator if the crap really hit the fan.
Bill
 
The boat has plenty of water tank capacity. The owner runs his generator all the time and wants lots of water available....
 
I am midway through my ongoing watermaker design/build. I have most of the piece parts except for the elements (membranes) along with one pressure vessel. My plan is to design the needed electronics right after the holidays followed by fabricating hand wired circuit boards for testing.

Based on my experience gathered so far into the project, I recommend a COMMERCIAL watermaker that operates on AC power. A DC unit is fine for a small boat but a boat large enough to have an on-board generator should go the AC powered route. And yes, one can build their own system, but it will require dedication. I remember reading someone's post last year who was attempting to build his own watermaker. I also remember another post from the same person who was selling his piece parts after giving up on the project. An AC powered unit should also work OK on dock power but an oil separator and good filters are a must.

One comment on DC units--- most know they only make a few gallons product/hour. But how many recognize that a system should be flushed with about 5 gallons of product after each use? Think about it.

Foggy
 
quote:
Originally posted by foggysail

One comment on DC units--- most know they only make a few gallons product/hour. But how many recognize that a system should be flushed with about 5 gallons of product after each use? Think about it.
Click to expand...


I only flush mine after each trip and pickle it only if it's going to sit a month or more.

Works out fine and maintains a constant 200-210 ppm of TDS.

But, since my boat is only 28' and I only have 50 gal storage capacity the 12v DC system serves my purposes just fine. I get plenty of water for cooking, drinking, head flushing and one good hot shower per day.

I run it whenever I am underway or when I have the gen running for charging or A/C.

Pascal is right though, if in brackish water I change the pre-filters every day. But, in trhe Bahamas I seldom change them during a trip.

Bob
 
I have an HRO system.
http://www.hrosystems.com/index.html

Bought mine used and rebuilt it. If I was to do it again I would go with the AC instead of the DC. I run my genset most of the time so I have 110 volt. I ended up getting a 120 volt to 12 volt converter and hooked it up to the watermaker. I plug the converter in to run the watermaker.

Remember the rated capacity is over 24 hours so you want to get the largest system you can to make enough water in the shortest time, when you want to run the system.
 
I know one thing: I ran into a Spectra rep last year at Annapolis Cruisair. I had some questions about my Katadyn and he had all the answers. Not only does he own a Katadyn, but a number of Spectra employees do (smaller boats, of course). He said Spectra almost bought the Katadyn brand as a way to offer an entry level product. Their research shows that once a boater has a watermaker, they will continue to own watermakers. I agree.
 
That's because they are not willing to accept the notion that it will never pay for itself. :)

Actually it's because the convenience is difficult to give up.
 
quote:
Originally posted by mixman

Their research shows that once a boater has a watermaker, they will continue to own watermakers. I agree.

Click to expand...


+1

Having a watermaker greatly increases my independant "on the hook" time. Find a nice little island, nice little cove, drop the hook and stay put.

You gotta love it.

I've made one trip since I swapped my home built unit for the Katadyn. The little bugger does a very nice job, very little current consumption and easily maintains 200 ppm TDS. For my boat the output is plenty. If I ever though about upgrading it I would most certainly go to a larger Katadyn. Very simple, easy to operate and maintain and puts out some very tasty water. :)

Bob
 
Bob,

Which Katadyn did you put in, the 80E?
 
quote:
Originally posted by mixman

Bob,

Which Katadyn did you put in, the 80E?

Click to expand...


40E with a boost pump. I get about 2.5 gph from it. That's actual determined by filling up milk jugs and watching the clock. :)

Bob
 
We've got the 80E, with the extra pump as well. They're great little units. We'll compare next June when we're all together across the stream! :-)
 
quote:
Originally posted by mixman

We'll compare next June when we're all together across the stream! :-)
Click to expand...


I can't wait! June can't get here fast enough. I was thinking about a trip to the Berry's over Christmas but the weather just looks really snotty so i guess I'll stay home.

Bob
 
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