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dpollitt · 29-06-2008, 12:33

I want to install a 12 volt watermaker...ie spectra, katadyn etc.. Can anyone give me good advice as to which maker to go with and/or features to look for.

Im not wanting alot of water - in the 4-8 gph range. Does the quality of the water 'made' vary from maker to maker?

Many thanks
david

senormechanico · 29-06-2008, 20:39

I've had a PowerSurvivor 35 purchased used, also an 80 (better)which was also second hand, and now I have a Spectra 180 which came with the boat I believe it's vintage 1998.

IMHO the Spectra is by far the best of the three. It's certainly the most efficient as well as not irritating to listen to when it's operating. I get about 6.5 gph when at anchor and almost 10 gph when motoring. PPM measures around 170 after a couple of minutes and 125 after it's been running for about ten minutes.

Steve B.

Active Transport · 29-06-2008, 22:33

Choosing the right reverse osmosis system for your needs involves a lot of details about your boat, you life style, and how you intend to use the water maker.

I decided on the village marine system for the following reasons.

1. there is no proprietary magic in this water maker business. All of the systems on the market are dependent on the same sources for the critical components of the system. The magic happens at the membrane (these membranes would not be affordable for us sailors if it were not for the apple juice industry) and none of the systems providers has a corner on any membrane technology.

2. The efficiency of the spectra system comes at the price of size, complexity and dependency on a lot of proprietary components for repairs and maintenance. Other, less efficient, systems use more commonly available components.

3. Not all amp hours are created equal. If you are running your water maker off your batteries at anchor then the efficiency of the spectra may make sense. If you run your engine often enough for other reasons then the amp hours to make water are virtually free. Also consider how much of your existing fresh water reserve does it take to start up the system. That has to be deducted from the productivity numbers the manufacturers provide.

4. Have a look at the installation instructions for all the different manufacturers. The spectra instructions seem to be very concerned with bubbles and require a larger dedicated through hull with a scoop.

I think that the major manufacturers in this industry provide products that honestly perform as advertised but the same solution is not appropriate for every application

I originally intend to buy a spectra system but as I looked into it in more detail I decided that the energy efficiency was not worth the negatives for me and the way I intend to use the system.

dpollitt · 30-06-2008, 05:33

Many thanks for the answers on the watermakers front.
david

AnchorageGuy · 30-06-2008, 06:19

Been running a Village Marine Little Wonder for several trouble free years and use it extensively.

Delezynski · 30-06-2008, 07:36

Dpollitt,

You might want to take a look at a write up I did on water makers and power in our 2 year gear report. I talk a bit about things to consider. You can go to our WEB site or direct to the gear report at:
Guenevere's 2006 Gear Report.

Greg

Microship · 30-06-2008, 07:58

Despite lower conversion efficiency compared to the Spectra Newport, I opted for the Katadyn 40E for pure long-term survival reasons... if the power fails, it can still be operated with a hand lever.

Steve

senormechanico · 30-06-2008, 18:32

Quote:

Originally Posted by Active Transpor

I originally intend to buy a spectra system but as I looked into it in more detail I decided that the energy efficiency was not worth the negatives for me and the way I intend to use the system.

That bubble stuff is news to me. The unit was already installed on the boat when I bought it and it just takes water from a shared non screened intake thruhull amidships.

No problems in 8 years.

Steve B.

Active Transport · 30-06-2008, 19:19

I got the info about the dedicated through hull and bubble problems from the Spectra manual and also from the Boat Yard that installs them in Alameda, CA.

It seems unlikely that they would put those constraints on the installation parameters unless some installations have problems.

Dont get me wrong. I think the Spectra system is a very cleverly engineered product and it has a good reputation. It just provides features, at a premium price, that I did not put much value on.

The same can be said for Village Marine's products. The village marine system is simpler (more complicated to use, maybe) and cheaper. It uses more amps per gallon but, like I said in my previous post, all amp hours are not created equal.

Everyone needs to evaluate these systems in terms of the way he intends to use them.

**Pblais** · 30-06-2008, 20:02

Quote:

Everyone needs to evaluate these systems in terms of the way he intends to use them.

That seems to be true for anything aboard. It would be nice if there was just the right answer so all else could be wrong. Just buy this one and we all move along.

All amp hours are equal it's just how you make them that are not the same. The statement that they are not all equal adds confusion where there is none what so ever and is meant to confuse the situation.

Quote:

I think the Spectra system is a very cleverly engineered product and it has a good reputation. It just provides features, at a premium price, that I did not put much value on.

That would mean it really is better but costs more but you run the engine less. It's not just a little bit more expensive either.

Quote:

The village marine system is simpler (more complicated to use, maybe) and cheaper.

It's cheaper, but you run the engine more and it's harder to use. The being simple part was an illusion. It's really cheaper though.

Sometimes the cheaper product is considered better and sometimes the better product is more expensive. Such is the way of things. Evaluation is a complex process. There are few clear answers on technical subjects and that in itself leads to more complexity.

It is possible for both to be appropriate in any situation that is more one way or another. It is also very true and important to note a system that you have that works well and you know is better than something you don't have. Getting over the curve of it all is not trivial but none the less important. If you have to make water you are in the game.

Active Transport · 30-06-2008, 21:43

Paul,

I dont think I have made myself clear on this

If I run my engine for other purposes, making water is free.

After the first half hour of battery charging the batteries wont accept everything the alternator can deliver (assuming the batteries were somewhat discharged when you started). For the balance of the charging cycle the alternator has excess capacity that is not being used. Making water with those amp hours does not mean that I would have to run my engine more. In this situation I have to run my engine to charge the batteries even if the alternator's output is constantly decreasing during the process. Why not use the excess alternator capacity to make water.

On most days my solar panels have topped up the batteries by noon and there is no where to store their additional output. That is a time that turning on the water maker makes sense and its efficiency is not such a big issue since the solar panel output would be wasted if not used.

**Pblais** · 01-07-2008, 03:58

I understood what you meant but it still leaves the question of if on most days the solar panels have toppped up the batteries by noon why would you ever run the engine? It must not be true more days than it is true or you would not need to run the engine. It must also be true that you would run the engine less if the power demand were lower no matter what method you used.

I understand the behavior of charge acceptance, but at lower alternator output the engine does not work as hard as when it's a full load off the alternator. There really are no free amps you just have to put up with the similar noise and it still consumes fuel but at a lower rate. So it does mean that on most days you do run the engine and the solar panels have not topped off the batteries or at least on the days you make water.

I have already agreed that there are multiple ways to look at it and ways that work to get the job done really do work. I don't question the efficacy of your process because I believe it works if only for the reason it has to work or the batteries would be dead. Since there are no free amps you take some out and you put some back. You need to waste some or the process degrades quickly because no process of making or consuming power can be perfectly efficient. The batteries eventually all go dead down the road.

I only question the notion that because one method is more efficient at a higher cost it has less value because you can get free electricity for the lessor efficient method at lower cost. That might be true if the amps were really 100% free but they are not free. It seems more an argument to negate the more efficient method that uses less power since you claim you never use it all so it's free. The power use difference is not insignificant nor is the price difference.

The price difference is a concrete number since the prices are available. The power numbers are not so clear since published numbers are subject to different means of computation but if you take the published numbers it becomes a ratio of 9 vs 13 amps per hour for an almost similar amount of water made so better than a 30% power advantage.

Active Transport · 01-07-2008, 07:37

I think its more of an argument saying that the greater efficiency may not be as valuable in reality as it is on paper and that extra dollar cost, bigger size, sole source for parts, and fussier installation requirements are something that should be taken into account when deciding which product is most suitable for a given application.

**Tellie** · 03-07-2008, 22:24

Quote:

Originally Posted by dpollitt

I want to install a 12 volt watermaker...ie spectra, katadyn etc.. Can anyone give me good advice as to which maker to go with and/or features to look for.

Im not wanting alot of water - in the 4-8 gph range. Does the quality of the water 'made' vary from maker to maker?

Many thanks
david

David, I sent you a PM.