12 volt water maker suggestions

[donradcliffe]

I've used a PUR/Katadyn 80 for years, and would look elsewhere for my next watermaker. The parts/pricing policy was bad enough under PUR, and got worse when Katadyn bought them out. Unless the boat has lots of excess solar, I would also get a higher output DC unit so you can make a lot of water when you do motor.

[Greasepower]

I'm looking at the 60gph 12v system from diywatermakers

seems great value and run it right before peak solar hours and let batteries recover after

[rebel heart]

Originally Posted by donradcliffe

I've used a PUR/Katadyn 80 for years, and would look elsewhere for my next watermaker. The parts/pricing policy was bad enough under PUR, and got worse when Katadyn bought them out. Unless the boat has lots of excess solar, I would also get a higher output DC unit so you can make a lot of water when you do motor.

I'd definitely agree that it's largely about your charging profile. If you spend lots of time with the engine off but use lots of solar and/or wind then a low output DC system is nice but for folks who reliably run the engine at least every several days than something a bit bigger might be nice.

[belizesailor]

Originally Posted by rebel heart

I'd definitely agree that it's largely about your charging profile. If you spend lots of time with the engine off but use lots of solar and/or wind then a low output DC system is nice but for folks who reliably run the engine at least every several days than something a bit bigger might be nice.

Both a low output/low power usage mode and full output mode would be a good feature.This would allow you to run longer but stay w in the capacity of your alt energy sources. I know one person who set up their Spectra to do this and have seen references to it in Spectra doco. I think they do it with an external speed control for the feed pump motor.

[belizesailor]

Originally Posted by barnakiel

Many owners say buy biggest you can and I can see their point.

I like Spectra wm much as I do not like their control panels (the highly automated ones). I would buy a Spectra for our boat too.

b.

Yes, like ground tackle, go at least one size class bigger than you think you need. I have a 12 GPH which is adequate for both cruising and charter use, but I wish I had gone w 20 GPH.

[colemj]

Originally Posted by Greasepower

I'm looking at the 60gph 12v system from diywatermakers

seems great value and run it right before peak solar hours and let batteries recover after

That thing draws 70A DC! And you really can't practically run watermakers for less than an hour, so that is a pretty big hole to crawl out of with solar - particularly since you suggest running it in the morning when the batteries are at their lowest.

With battery voltage <13.8V and voltage drop in the undersize wiring (are you really going to wire it with 1/0 AWG?), I suspect this unit will draw 80A in practice.

I haven't been on DIYwatermaker's website in a while. They are now claiming gallon per amp values that are way lower than their past units and are similar to units using energy-recovery pumps. They are certainly lower than any other non-recovery system.

Do you know if they have changed their designs? I would put some serious questions to them about this, or you could be surprised.

Mark

[Cotemar]

colemj,

You have been cruising for a long time.
What is your next watermaker going to be?

[colemj]

Just bought it yesterday. A 30gph AC powered one from CruiseRO. It is replacing a perfectly good 6gph unit.

Do not underestimate the amount of water you will want/need out cruising. Particularly in the tropics and in places where water is difficult or inconvenient to get. We consider an entire day jugging water, or having to pull up from a beautiful anchorage and travel for a day, or pulling along side a rusty spike-encrusted piling as inconvenient.

We drink 4 gallons of water a day in the tropics, like to shower off and rinse gear after each of several swims and dives, want to wash dishes in fresh water, want to do laundry (by hand) regularly, and hate having salt icicles hanging from the boat when we are anchored behind barrier reefs in the tradewinds.

6gph kept up with our needs, but we were finding we needed to run the generator to do so, even with 480W of solar. So, if running the generator occasionally (or motoring with 180A of alternators), why not make 30gph and always have full tanks?

Anything less than 6gph would put us into camping mode and not living mode. I realize this statement makes me a target for those using 1.5gph units, but frankly, I don't see how they get by with those without adopting a camping style of boating. Like I said, we drink 2-3 hours worth of their output each day.

And to head off the other critiques, we have 480W of solar, do not want a windgen and have a permanent rain catchment system that provides 100gph when it rains hard (the problem in the tropics is that it does not rain for 6 months at a time).

I guess we are pampered and piggish...

Mark

[Zanshin]

I like my Spectra Catalina a lot, it is very quiet and is an energy miser. I had a problem with the salinity probe breaking, but used the manual mode until I was in St. Martin and got a factory warranty replacement.
The BVI really are very expensive, but instead of dropping watermaker $ at Parts & Power I'd do the uphill slog and buy at Electec in St. Martin for a much lower price and they have a lot of watermaker expertise and carry shelves full of spare and replacement parts.
Winter 2011-2012 Blog and Diary 2011-12-23

[Cotemar]

colemj,

That CruiseRO SM 30 at $5000 usd makes a lot of sense.

I talked to another cruiser in Newport RI. last week that has been on the water for ten years now and he is using a 50 gal per hour DIY engine driven watermaker for two adults and two kids in cloth diapers. They use a Danby washer to clean their cloths.

What kind of generator are you using?

[colemj]

NextGen 5.5

If money was no object, I would consider a higher output 12V Spectra-type unit. The energy management/output need equation would balance better. I do question the reliability, as we meet so many people with problems - although almost all of them are having problems with ancillary automation electronics, which I would not have on mine.

But money is an object, and they cost over double.

Mark

[goboatingnow]

given the disparity between 6gph and 60gph and even Colemj going from 6 to 30, what is the figure people would agree is optimum. I built a water maker some time ago ( 220VAC powered) but would like to experiment with a 12/24V one this time ( Im looking at some energy recovery solutions) kinda of a winter project.

DAve

[colemj]

I estimate 15-20 gph as optimum for us.

In considering a new watermaker, it seems like the only difference between 20 and 30gph in everyone's units was a second membrane - the components and power consumption is the same. So I bumped up to the larger unit.

Above 30gph, the size and power need changes. I wanted to be able to run it off the inverter while motoring, and the larger units would draw too much power. They also draw too much for the common suitcase generators.

Mark

[rebel heart]

Originally Posted by colemj

Anything less than 6gph would put us into camping mode and not living mode. I realize this statement makes me a target for those using 1.5gph units, but frankly, I don't see how they get by with those without adopting a camping style of boating. Like I said, we drink 2-3 hours worth of their output each day.

And to head off the other critiques, we have 480W of solar, do not want a windgen and have a permanent rain catchment system that provides 100gph when it rains hard (the problem in the tropics is that it does not rain for 6 months at a time).

I guess we are pampered and piggish...

Mark

I'm not knocking anyone for bigger RO units; honestly I think boats have a lot of flexibility in their choices and it's not like picking between a diesel or gas inboard where one option is clearly better than another.

We burn about 6 gallons a day, on average, between showers, drinking, dishes, and the rest. Sometimes more, sometimes less but 6 is a good average for us. Leaving the watermaker on for 4 hours a day just isn't that inconvenient at all for us and with the low amp consumption we don't really need to factor in engines or the generator.

[belizesailor]

Keep in mind when sizing that you will probably use more water when you have a water maker. Certainly been my experience. Less conservation motivation when all you have to do is push the majic button.