Watermaker
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The friendliest place on the web for anyone who enjoys boating.
If you have answers, please help by responding to the unanswered posts.
If you have answers, please help by responding to the unanswered posts.
psneeld
Guru
...that's the example of what I was really talking about....
ksanders
Moderator Emeritus
Which is based on your GPD needs.
And that is why a higher GPH unit can be worth the extra money because you can run it less HPD to produce the amount of water you need for the coming days.
The problem is often not the cost of the higher output models, its the size.
When I had my boat refit and added the watermaker the shipyard had access to a couple year old takeout watermaker from a much larger boat. It had a large capacity, I do not remember but it was several hundred gallons per day.
The price was right. The size wasn't. The thing was huge. It would have not only required completely redoing the layout of my lazarette, it still would have fit so tight as to make maintenance a nightmare.
I opted for a 160GPD model, and paid more for it, but it actually fits in my lazarette and I still have room to move around and actually perform maintenance.
I have to run my generator approx 6 hours a day on the hook to keep the batteries up. That gives me time to make approz 42 gallons of water, which is in the range of what us two people actually use on the boat. A little make up water from time spent cruising and we're golden for laundry.
BTW, our watermaker is a DC unit. We do not need the generator running but like to run it when we run the watermaker because of the noise of the watermaker, which makes a thumping sound, significantly louder than the generator, which we cant really hear.
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Capt.Bill11
Guru
That is exactly what I was talking about. The GPD you use on your boat. Not the GPD the the watermaker makes . The faster a unit will top off your water tank/s and make up for whatever water you may be using while the maker is in use the less you have to run your Genset , engine or what ever to make that water.
Capt.Bill11
Guru
Yes and that is one of the good things about the modular units. Their parts can be remotely mounted from each other to best take advantage of the space available. Unfortunately in smaller boats there may not be enough space available even for a larger output modular unit.
FF
Guru
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Read the GPD , divide by 24 , and decide how many hours you wish to power it .
There are DC units , but a couple of V belts is the least maint.
There are DC units , but a couple of V belts is the least maint.
Capt.Bill11
Guru
About all you gain with an engine driven unit is the elimination of an AC or DC motor to drive the HP pump. Both of which are pretty reliable and require little or no routine maintenance.
In exchange for eliminating the electric motor you end up having to run your main engine to make water. Which might be fine if your moving for several hours every day or so. But if your at anchor days on end, it seems counter productive to me to ad run hours to your engine while remaining still.
In exchange for eliminating the electric motor you end up having to run your main engine to make water. Which might be fine if your moving for several hours every day or so. But if your at anchor days on end, it seems counter productive to me to ad run hours to your engine while remaining still.
FF
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Why the big engine?
Most noisemakers would appreciate lower AC loads while starting/operating air cond, so a watermaker and big commercial DC alternatior would be a fine balanced load fot 2 shives on the unit while in operation.
Lots of folks operate the noisemaker 10X as much as the propulsion engine .
Water water everywhere , with lots of gallons to drink!!
Most noisemakers would appreciate lower AC loads while starting/operating air cond, so a watermaker and big commercial DC alternatior would be a fine balanced load fot 2 shives on the unit while in operation.
Lots of folks operate the noisemaker 10X as much as the propulsion engine .
Water water everywhere , with lots of gallons to drink!!
Capt.Bill11
Guru
Yeah you could run it off the Genset engine I guess. I thought you were referring to running it off the main engine.
Efficiency wise I'm not sure you gain anything by doing that. And most gensets are running well under their ideal load even when ACs are cycling. So the constant draw of a large AC motor could be better for the Genset than running the pump directly off the crank. But I'm not 100% sure on that.
FF
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And most gensets are running well under their ideal load even when ACs are cycling.
The oversizing is usually done by the boat assembler , after all he does not deal with the fuel bill. And 40% of 15KW is a better commission than 40% of 6kw .
For many boats that serve as dockside waterfront cottages , on the few outings a year the 15KW is a better option.
NO learning curve.
For a cruiser ,with seasons away from the power pole,, maybe not.
The oversizing is usually done by the boat assembler , after all he does not deal with the fuel bill. And 40% of 15KW is a better commission than 40% of 6kw .
For many boats that serve as dockside waterfront cottages , on the few outings a year the 15KW is a better option.
NO learning curve.
For a cruiser ,with seasons away from the power pole,, maybe not.
Billylll
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You guys know that you can revive the filters by dragging them behind the boat using a small diameter rope. I can usually get 3 uses out of the filters after the pressure initially gets too high by drag cleaning them behind the vessel.
Bill
Bill
Capt.Bill11
Guru
I have back flushed filter out with fresh water many times. But never tried dragging them behind the boat.
My questions would be, what kind of stuff are you collecting/forcing into the wrong side of the filters as you drag them through the water? And are you washing them out with fresh water after you drag them?
My questions would be, what kind of stuff are you collecting/forcing into the wrong side of the filters as you drag them through the water? And are you washing them out with fresh water after you drag them?
Billylll
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Actually I learned this from my Spectra dealer. I drag them behind the boat at hull speed then wash them off with fresh water then wait 24 hours and re-install it's worked to extend the life of the filter elements. It works really well Capt Bill.
Bill
Tomas
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Tidahapah
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Why would you bother, the filters are pretty cheap and easy enough to change out.
I would imagine dragging them behind the boat is going to weaken the filter material and before you know it you have filter material heading for your HP pump and beyond.
Cheers
Benn
I would imagine dragging them behind the boat is going to weaken the filter material and before you know it you have filter material heading for your HP pump and beyond.
Cheers
Benn
psneeld
Guru
Billylll
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Your a real comedian aren't you? I'm trying to give real world advice that works.It's remembering to tie them in front of the laundry tub that's tricky...
Do you have anything constructive to add to the topic?
Bill
mbevins
Guru
Capt.Bill11
Guru
While they are cheap, they can take up a fair amount of storage space. And if you're in an area with a lot of plankton in the water or the water silts up you can end up going through a lot of them.
So I have washed out a few in my time to reuse them. Just never thought of nor heard of dragging them to do it. But I can see how it would work if you rinced them out afterwords.
Billylll
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It's not a big deal and I would have never thought of it until a service rep told me it's a good tip if your on a long trip and have run out of filters. With each drag they don't last as long but it's a neat trick that works if your flat out of filters.
Bill
Bill
