Selecting A Water Maker-a Lesson Learned The Hard Way. Maybe This Will Help Someone?

[zstine]

For you watermaker gurus... What fresh water output would you expect from a system using a 1/3hp motor, driving a 0.5gpm pump (WM0515C) and a 21" membrane? like 6 to 7 gph?

thanks
zach

BTW, the seller of the 1/2hp, 12VDC motor who claimed 27Amps full load was indeed wrong. The 27A spec is for a 1/3hp motor, not 1/2hp.

[SV THIRD DAY]

Originally Posted by zstine

For you watermaker gurus... What fresh water output would you expect from a system using a 1/3hp motor, driving a 0.5gpm pump (WM0515C) and a 21" membrane? like 6 to 7 gph?

thanks
zach

BTW, the seller of the 1/2hp, 12VDC motor who claimed 27Amps full load was indeed wrong. The 27A spec is for a 1/3hp motor, not 1/2hp.

I'm happy we cleared up the 1/2Hp motor power usage issue, because unfortunately it is usually something figured out after the unit is all hooked up and the batteries are crushed. It's also why the DIY route can cost as much or not more...the price of learning and mistakes.

5-7GPH is about fight for a 0.5gpm pump, 1/3hp motor and 21" membrane and figure on 35 amps 12v DC for the motor and boost pump. Also....plan on only running that type of load from your battery bank when your alternator is running...it's just too large a load for lead acid batteries and solar. Don't get me wrong, I'm not trying to be a parade rainer, but I just have the advantage of having cruised and living aboard with a family of 4 for 9yrs. It is a constant struggle is keeping your battery bank alive and not showing 12.1v in the morning.

[a64pilot]

For the guys that do go the AC route and want redundancy in power generation, yes a second generator can do that, but so can a large alternator and inverter that you may already have anyway.
I have run the power numbers over and over and based on some experience of us being gone a few weeks at a time, and I can't make it work with 750 W of Solar, yes it will work most of the time, until you get several days of rainy overcast days or Winter with its overcast short days. So I figured I'd need a generator to supplement as I don't want to run the big motor to charge batteries. If I'm going to have a generator anyway, may as well go with an AC high output watermaker.
I based my need of a generator based largely off of Mainesail and others opinion whom I respect informing me that you just can't get to truly 100% SOC off of Solar alone, just not enough hours of useable Solar

I read where someone wanted to run a high output DC watermaker that draws 40 amps in the morning. It may make better sense to wait and run it when your Solar is making more power than your batteries can absorb, a little later in the day. That way your not knocking your SOC as low and will be using what would otherwise be wasted power.


Sent from my iPad Pro using Cruisers Sailing Forum

[SV THIRD DAY]

Originally Posted by a64pilot

I read where someone wanted to run a high output DC watermaker that draws 40 amps in the morning. It may make better sense to wait and run it when your Solar is making more power than your batteries can absorb, a little later in the day. That way your not knocking your SOC as low and will be using what would otherwise be wasted power.

What we did at anchor when I didn't really have enough solar was to run the Honda and water maker in the mornings, that way I would get some bulk charge into the bank so that solar would have a better chance to get the batteries back to 100% SOC during the afternoon. At least once a week (call it 7 discharge cycles), I would then let the Honda run for an hour or so longer after water making to really charge them well. The No 1 problem off the dock cruisers have is not getting their Lead Acid batteries back to 100% SOC enough, which causes sulfation and loss of capacity....been there....done that...got the T-shirt...

[senormechanico]

Originally Posted by jamhass

One additional point to consider is noise, and the duration of the noise. We had limited options for mounting our Spectra 150, and that involved placing the feed pump on a bulkhead that happily acts as a sounding board. Certainly not noticeable underway, but an irritant at anchor, especially when we need to run for 3+ hours... This is indeed when we wish we had a higher output unit!.

Although the sound wasn't particularly offensive, I was looking for a boat project so I moved our Spectra 180 feed pump to a bulkhead mounting under our berth.
I now have to set a timer to remember to shut off the watermaker because it's so quiet !
Take a look at isolating the pump with an insulating sheet of that stiff, shock absorbent closed cell foam which is used in shipping.
Rich,
Get some Lithiums if you haven't already done so.

[Dulcesuenos]

Originally Posted by SV THIRD DAY

What we did at anchor when I didn't really have enough solar was to run the Honda and water maker in the mornings, that way I would get some bulk charge into the bank so that solar would have a better chance to get the batteries back to 100% SOC during the afternoon. At least once a week (call it 7 discharge cycles), I would then let the Honda run for an hour or so longer after water making to really charge them well. The No 1 problem off the dock cruisers have is not getting their Lead Acid batteries back to 100% SOC enough, which causes sulfation and loss of capacity....been there....done that...got the T-shirt...

OK just wondering here. The specs for the Honda 2000 are continuous output is 13.3 amps and a max surge of 16.7 amps
Your smaller pump draws 9.3 &your larger draws over 11amps
Not counting a 12v feed pump also right?
The average charger is what 6-15 amps of AC draw?
How are you running both the your water maker and a battery charger at the same time without the Honda screaming its guts out or tripping its breaker? I must be overlooking something.



Sent from my STUDIO 5.5 using Cruisers Sailing Forum mobile app

[SV THIRD DAY]

The 1.0Hp motor on the 20 and 30gph water makers are identical and use 9A at 115v AC.
The Honda's continuous steady state load rating is 13.3A.

So once the water maker is running you can turn on your battery charger, but you want to start the water maker first so it can handle the start up current. Now you have 4.3A of AC power left, so that can run a 40A DC battery charger. Many better quality chargers will let you dial up/down the input amps or the output amps. That's one reason I like the 60A Sterling battery charger because I run it at 60A from the Honda when not making water and then dial it down to 40A when making water.

Now, yes the 12v DC boost pump is using 8 of those 40A...but 30A going into the battery back ain't shabby. People always ask why we put the Boost pump on 12 volt DC rather than 120 volt AC. The reason is that it makes it much easier to fresh water flush your water maker without having to take out and start your generator. Just push the button and turn on the Boost pump for 3-4 minutes and you're done with the fresh water flush, or you can easily let the automatic fresh water flush do it for you with no need for a generator or AC power. Being a liveaboard cruiser myself, I know if maintenance is easier to do you're more likely to do it....

[SV THIRD DAY]

Originally Posted by senormechanico

Rich,
Get some Lithiums if you haven't already done so.

I've had LiFePO4 batteries for about 2.5yrs now...it changes everything....

[accomplice]

I'm going to jump in here with my $0.02. I fully understand and agree with the OP -- a higher output watermaker is preferable for us, even if it were less energy efficient.

A previous owner installed a 39gph (900gpd) AC watermaker. I'm not about to replace it, but I do often wish it were bigger (greater output). Why?

In my former boat, with limited tankage, we were able to get down to 1-1.5 gal/day/person. We find that with only making modest water conservation efforts, most crew is quite comfortable at 10gal/day/person, and that is generally our usage while cruising. We generally draw from one of the ~120 gal tanks. If anything happens with the watermaker or genset (10 kW), we have at least 120 gallons left, and that is likely to last, if we conserve, until we can get to a dock to refill the tanks and/or fix the watermaker/genset.

While we don't passage with as many, we often have ~10 people on board. We would have to run the genset for an hour a day (with a 24V/120A charger running ~80A) anyways to supply the needed power for refrigeration, microwave ovens, radar, TVs, hair dryers, etc. -- so we use the opportunity to make water and, some days, run the dishwasher and/or washer/dryer at the same time. The problem is that our water consumption (10ppl x 10gal/day) requires 2-3 hours of generator time a day to replenish. If our watermaker were twice the capacity, we could reduce our genset running time when hosting more crew/guests to that which is needed for recharging the batteries/running a load of dishes/clothes, etc.

I potentially could run the watermaker off the 5000W inverter, but I would just be running the genset more to charge the batteries back up. It wouldn't help me that much.

Our watermaker is a Sea Recovery. I'm ok with its performance, but the use of non-standard parts is an inconvenience and an expense. Whether it be ~$100 filters, or non-standard booster pumps, I have frequently questioned whether the choices made by the systems' designers were really made keeping in mind the needs of the cruising sailor, or whether they were focused on the company's profits. I'm all for making quality component choices, but I wish designers only reverted to custom, single-source components when absolutely necessary, not at every turn.

I would suggest sizing a watermaker such that it doesn't add any more time to the daily or weekly generator running needs. At some point cruisers may, through wind and/or solar and conservation be able to eliminate generator running needs altogether. In my experience, we are far from that point. Running a primary engine with a large alternator, engine-driven AC generator, or engine-driven watermaker doesn't change the main point -- if sized wisely you won't have to run extra for water.

[travellerw]

Originally Posted by SV THIRD DAY

I've had LiFePO4 batteries for about 2.5yrs now...it changes everything....

Ya.. Friends of ours have LiFePO4 with 1200W of solar.. They run a 120V breadmaker (using inverter) every 2 days. I couldn't do that on my LA batts even if I had the extra 300W of solar!

However, down here in Grenada, the LiFePO4 batts are a problem as NO ONE here can help you with them. Any issues and you are stuck troubleshooting on your own through e-mail. Not a big deal for some cruisers, but a deal breaker for others!

I seem to have found the right balance of solar and LA bank. We have 900W of solar and 660AH of battery. We hit 100 SOC between 11:30am and 12:30 every day. However with our "smallish" bank I really should have added wind for those cloudy days.

[ErikFinn]

Originally Posted by SV THIRD DAY

The 1.0Hp motor on the 20 and 30gph water makers are identical and use 9A at 115v AC.
The Honda's continuous steady state load rating is 13.3A.

So once the water maker is running you can turn on your battery charger, but you want to start the water maker first so it can handle the start up current. Now you have 4.3A of AC power left, so that can run a 40A DC battery charger. Many better quality chargers will let you dial up/down the input amps or the output amps. That's one reason I like the 60A Sterling battery charger because I run it at 60A from the Honda when not making water and then dial it down to 40A when making water.

Now, yes the 12v DC boost pump is using 8 of those 40A...but 30A going into the battery back ain't shabby. People always ask why we put the Boost pump on 12 volt DC rather than 120 volt AC. The reason is that it makes it much easier to fresh water flush your water maker without having to take out and start your generator. Just push the button and turn on the Boost pump for 3-4 minutes and you're done with the fresh water flush, or you can easily let the automatic fresh water flush do it for you with no need for a generator or AC power. Being a liveaboard cruiser myself, I know if maintenance is easier to do you're more likely to do it....

Hi Rich,

I'v been reading and learning about watermakers for some time now and I know the basics but not much details.. Its a learning process..

I noticed you sell some modules in addition to full kits and I would like to research the possibility of building my own WM, using some or all of your modules. I'm sorry but at the moment I can't afford to buy a complete system. And yes I have read some folks have made expensive trials and errors trying to build their own WMs. And sorry but I cant give up tacos and beer (green curry and Chang) for a WM, you know what I'm saying?

I guess my main question here today is: Would I be able to save any money by gradually buying your modules and building the system in steps, instead of a complete kit at one go?

I would actually prefer the SM30, but its about 850 bucks more expensive than the SM20. I know you offer the "Simple" version SM20S with a USD 395 savings but it doesn't come with the control panel and I DO like the control panel so lets concentrate on the SM20. Nevertheless, I understand I could later upgrade to the identical specs of the SM30 by just adding one vessel & membrane, that's it? Motor and pump and everything else stays the same?

So, for the sake of simplicity and cash savings, let's say I want to build something like the SM20.

The price at your site currently is USD 4'395, here:

20 GPH Water Maker | Marine Watermakers | Cruise RO Water & Power

The motor and the high pressure pump head; the SM20 uses the 1hp motor and the 1.6GPM pump priced at USD 1'500 (Fully Assembled Module #1A) as per here?

Watermaker Parts & Accessories by Cruise RO Water & Power

Then I'd need the pressure vessel and membrane with mounting feet and clamps, priced at USD 750 (Fully Assembled Module #2A)

That should be most expensive items there totalling USD 2'250.

The boost pump you don't appear to be selling but I reckon 150 bucks should do it for an equal one from Defender? Something around 4 GPM and 40psi so to keep a nice positive pressure and flow in between the boost pump and the high pressure pump, and I reckon you are using washdown pumps?

Then the prefilter and the valving&cleaning assemblies, and the Standard Remote Panel, and some high pressure braided hose for membrane and the panel. Filter units are about 100 bucks, but the valving unit and Panel you don't seem to be selling, I'd estimate 30 for the former and 450 for latter? 100 for the high pressure hoses?

What else would be needed? I reckon thats it. Except that you include the Cruising kit with the SM 20, sold seperately at USD 165, I reckon its also needed if one wants to keep on making water for more than few weeks..

Oh and all these modules must be puzzled together somehow with water tubing (various), some tools, connectors, clips, and a manual. Also included in the SM20 Complete System are some pickling agent and TDS meter; detailed listing on the SM20 page under "Miscellaneous Included Equipment & Supplies".
How much should be budgeted for these items? I'm not educated enough to give a monetary value, but if my calculations are correct you appear to value them at around USD 1'150 (4'395-3'245 (from below))

Motor & pump: 1'500
Vessel & membrane & fittings 750
Boost pump 150
Filter assemblies 100
Valving unit 30
Panel 450
Hi pressure hoses 100
Cruising kit 165

Total less Miscellaneous items: 3'245

At first glance USD 1'150 seems like a lot for tubing and connectors etc. but I do know there is value in details when you don't have to go parts hunting and everything "just fits".

Do you sell the "Miscellaneous Included Equipment & Supplies" if I wanted to buy itseparately? If yes, at what price?
Also, when shipped to abroad is there any VAT/GST/Sales Tax break I could expect?

BTW, my intention is NOT to reveal your trade secrets or markups or anything disrespectful. I would just like to form an educated view about what I can afford and what I can not afford. Heck, I may even abandon the whole project. But my sometimes over-analytical mind demands feeding for now.Thanks.

[SV THIRD DAY]

Hi Erik
You are making the mistakes most guys make as they contemplate the DIY route, which is dramatically under pricing some of the "small parts". It's Sunday and I'm at a BBQ, so I won't do an exhaustive inventory, but let's hit some low hanging fruit.

The ONLY difference between the 20 and 30 GPH unit is the second pressure vessel and membrane and $855. But we sell the pressure vessel and membrane with mounting feet for $750...so where is that extra $105? Well the $750 for the membrane unit doesn't come with and low or SS Hp inlet outlet fittings...then there is the SS cross over tube to connect the two pressure vessels in series. These fittings are not cheapermitted and $105 disappears before you know it...

Hp hoses... $100?
Try $165 for a 3ft hose and then $10/ft.
If you can find it for $100 let me know so I can buy some. Not hydrolic hose...but NSF certified drinking water hose.

$30 for the valving unit?
Well the 3-way valves are $35ea anf there are two of them, the filter housing is $25, bracket 5, AC filter $9...then the inlet/outlet fittings.

I didn't see the $127 pressure relief valve on your list?
Or the $30 SS Hp fitting for the Hp Pump outlet to attach to you Hp hose.

I see this literally all the time when folks start down this path. They forget about the $4.50 per each low pressure fittings and before they know it their $1000 savings turns into less than $500. I know what these parts cost for the DIY guy (its my job to know) and we priced our unit accordingly to make it just not worth most people's time to go the DIY route and then have no warranry or a guy to call 7 days a week for help when something goes wrong.

Most of the people who by parts from us are retrofitting a current water maker and already have some components rather than building from scratch...the math just doesn't work for most if you count your incoming shipping costs and time trying to find all the parts on ebay and online. Sure I'll be happy to help, but I've just had so many DIY guys tell me that that should have just bought the full unit 3/4 of the way into it that I have to at least give that warning.

And who else do you know that will put down his Sunday BBQ plate to help someone or answer a question. Honestly, the reason we sell our water makers like hot cakes is because of our secrete called customer service. I call it a secrete because so many Marine vendors just can't seem to figure it out...

[Panacea2183]

Originally Posted by ErikFinn

Hi Rich,

I'v been reading and learning about watermakers for some time now and I know the basics but not much details.. Its a learning process..

I noticed you sell some modules in addition to full kits and I would like to research the possibility of building my own WM, using some or all of your modules. I'm sorry but at the moment I can't afford to buy a complete system. And yes I have read some folks have made expensive trials and errors trying to build their own WMs. And sorry but I cant give up tacos and beer (green curry and Chang) for a WM, you know what I'm saying?

I guess my main question here today is: Would I be able to save any money by gradually buying your modules and building the system in steps, instead of a complete kit at one go?

I would actually prefer the SM30, but its about 850 bucks more expensive than the SM20. I know you offer the "Simple" version SM20S with a USD 395 savings but it doesn't come with the control panel and I DO like the control panel so lets concentrate on the SM20. Nevertheless, I understand I could later upgrade to the identical specs of the SM30 by just adding one vessel & membrane, that's it? Motor and pump and everything else stays the same?

So, for the sake of simplicity and cash savings, let's say I want to build something like the SM20.

The price at your site currently is USD 4'395, here:

20 GPH Water Maker | Marine Watermakers | Cruise RO Water & Power

The motor and the high pressure pump head; the SM20 uses the 1hp motor and the 1.6GPM pump priced at USD 1'500 (Fully Assembled Module #1A) as per here?

Watermaker Parts & Accessories by Cruise RO Water & Power

Then I'd need the pressure vessel and membrane with mounting feet and clamps, priced at USD 750 (Fully Assembled Module #2A)

That should be most expensive items there totalling USD 2'250.

The boost pump you don't appear to be selling but I reckon 150 bucks should do it for an equal one from Defender? Something around 4 GPM and 40psi so to keep a nice positive pressure and flow in between the boost pump and the high pressure pump, and I reckon you are using washdown pumps?

Then the prefilter and the valving&cleaning assemblies, and the Standard Remote Panel, and some high pressure braided hose for membrane and the panel. Filter units are about 100 bucks, but the valving unit and Panel you don't seem to be selling, I'd estimate 30 for the former and 450 for latter? 100 for the high pressure hoses?

What else would be needed? I reckon thats it. Except that you include the Cruising kit with the SM 20, sold seperately at USD 165, I reckon its also needed if one wants to keep on making water for more than few weeks..

Oh and all these modules must be puzzled together somehow with water tubing (various), some tools, connectors, clips, and a manual. Also included in the SM20 Complete System are some pickling agent and TDS meter; detailed listing on the SM20 page under "Miscellaneous Included Equipment & Supplies".
How much should be budgeted for these items? I'm not educated enough to give a monetary value, but if my calculations are correct you appear to value them at around USD 1'150 (4'395-3'245 (from below))

Motor & pump: 1'500
Vessel & membrane & fittings 750
Boost pump 150
Filter assemblies 100
Valving unit 30
Panel 450
Hi pressure hoses 100
Cruising kit 165

Total less Miscellaneous items: 3'245

At first glance USD 1'150 seems like a lot for tubing and connectors etc. but I do know there is value in details when you don't have to go parts hunting and everything "just fits".

Do you sell the "Miscellaneous Included Equipment & Supplies" if I wanted to buy itseparately? If yes, at what price?
Also, when shipped to abroad is there any VAT/GST/Sales Tax break I could expect?

BTW, my intention is NOT to reveal your trade secrets or markups or anything disrespectful. I would just like to form an educated view about what I can afford and what I can not afford. Heck, I may even abandon the whole project. But my sometimes over-analytical mind demands feeding for now.Thanks.

But the whole kit from Rich
You'll be glad you did!

[tomfl]

Originally Posted by accomplice

SNIP

but the use of non-standard parts is an inconvenience and an expense. Whether it be ~$100 filters, or non-standard booster pumps,

SNIP

At this point I am only a lurker but this is not the first time I have seen a comment about what I will call "standard filters" or standard what evers. Not saying I would enjoy paying $US100 for a filter but if I only had to do that once a year/season (as now I generally lay up the boat for hurricane season) it would not break the bank.

My understanding was that a filter would last quite a while; especially if it was pickled correctly.

Of course I could be wrong about all of this.

[a64pilot]

Your confusing membranes with pre-filters, you filter to two different levels to try your best that the membrane only gets particulate free water.
Unless mistaken I believe a membrane if properly cared for will go for some number of years
Filters depending on water cleanliness will need cleaning and or replacing pretty frequently, I don't know the frequency though, but assume a muddy anchorage and crystal clear off shore water are completely different from a filters perspective, I think like a farm trucks air filter may need replacing monthly while a highway car can go maybe a couple of years


Sent from my iPad Pro using Cruisers Sailing Forum