fresh water pump?

mainshiptom

mainshiptom

Well-Known Member
Joined
15 Jul 2002
Messages
3,399
Location
Faversham kent uk
Visit site
What is the best water pump to use.

Just been told this by jabsco :
Your problem is mostly the 4-5 nights I think, most marine pumps (including Parmax 3) are designed and made to Marine Leisure use which is probably 20 nights per year max. and not much more than 600 litres per year.


Your views are welcome !

thanks

Tom
 
I refer the learned gentleman to my post on another forum.

They are not designed for liveaboard, or even close.
 
My refrigerator heat exchanger is cooled by seawater, pumped by a perfectly normal domestic water pump. It was second-hand when I acquired it and I'm not even sure what make it is. Definitely nothing special. The fridge has run non-stop from May to October for the past five years. The pump runs when the fridge cycles on, about 30% of the time when not too hot, about 50% at hottest.

The only difference between it and a normal water installation is that it runs on 6 volts rather than 12, via a voltage reducer. This is just to reduce the flow, so no major effect on bearings, valves, brushes, etc. Maybe a bit easier on the windings.
 
Running at 6 volts, no back pressure or very little and no pressure (micro) switch, I would expect it to last forever.
Not quite the same as a pressure water system.
 
Yes, I agree, although it's still quite impressive. My domestic water pump was replaced last year, it's the original one, so well over 20 years old. Used full time for its last four years and quite heavily before that. It became very noisy as the big-end bearing was worn, but still working.
 
Owned our cat for 10years spent every weekend on board,lived on board for 6 years , have Surflo 12v pump had to replace the pump triple diaphragm ,nice and simple job.
Would recommend them.
 
They were maybe good pumps a few years ago, now they are crap, its mainly the pressure switches and brushes. Jabsco, shurflo, flojet etc
When they are building a system designed for partial liveaboard, they use a much heavier duty pressure switch., doing away with the little plastic micro switch affairs.
They do not reccomend any of their systems for total domestic liveaboard type use, basically Cleghorn wareing said I would have to look elsewhere. Which I have, at Marco pumps italy, who make a far better pump with serviceable brushes and use teflon gears for the pump. I'm going with one of theirs. Have had enough of this jabsco stuff.

Englander needs a decent sized system, with washing machine, galley, instant gas hot water heater, two showers and three washbasins. Marco supply one of those, with adjustable pressure switch, 40 litres/min. in one pump, Jabsco et al, need two pumps and a lot of money!
 
I would have thought that the models used on charter boats would be heavier duty and a better bet.

On our ex charter boat (now 8 years old, six years on charter)we have a Jabsco Ultra-max system, apparently it played up a bit once on the day that I had the boat delivered just over one year ago, but the delivery skipper, had it to bits, cleaned and back together again in a few minutes, not needed to touch it since .

Jabsco Ultra-max
 
I have a parmax 3 in my boat, now 4 years old and has had no problems. Propbably pumps closer to 600 litres per week! I have no accumulator at all, so the pressure switch cycles alot. maybe this is helping it last longer?

Maybe you got a duff one. I cant believe something would be designed for so little use, but then maybe someone is out just to make money and sell us crap products.
 
My now obsolete Par-Mate Mini did 12 years, the last 4 at >3000l/year. When it failed the pressure swithch went and replacement was not an economic alternative.

The new ParMax1, operating at 1.8bar, has now done 4 years of work pumping in excess of 3000l/year. Apart from melting its plastic fuseholder, when a high-pressure pipe fractured and ir pumped 130l into the bilges, it has given not a moment's trouble.

I'd suggest a more likely source of trouble is inadequately heavy wiring to the pump unit, by the builders than inherent weaknesses built into the pump.
 
Why would inadequately heavy wiring to the pump cause the microswitches to fail, brushes to wear down prematurely and valves to fail?
I think you are wrong.
Plus of course 3000 litres ayear is not really liveaboard type pumping, with four people aboard, that's about 4 weeks worth @ 150 gals a week. Which is 37.5 gals per person per week, which is quite a lot, but showering etc does take up quite a bit.
Like I have said and the manufacturers have said and cleghorn waring (who know a bit about pumps) have said, these pumps are not designed for liveaboards, or for partial liveaboards, they are designed for occasional leisure use. Much better to have a non permanent magnet motor, with proper industrial pressure switch, designed for domestic water supply, but in 24/12volt, which is what I'm about to fit, having gone through at least 12 pumps in my 14 years of liveaboard, thats a lot of pumps and money!!
The original godwin pump fitted to the boat, lasted 20 years, I wish I had never changed it! Designed for the job!
 
Not our experience. We have lived aboard for five years and use around 700 litres per week. We are on the second pump; the first was old when we bought the boat but only needs new valves, which I have bought ready to fit. We are very pleased with the product.
 
small wires

= voltage drop leads to increased amps.

As anyone with any electrical knowledge will know that = more wear, arcing etc.

Still I'd hesitate to contradict such heartfelt prejudices.

For your info, I live aboard about 40 out of 52 weeks, but don't apparently squander water the way you do.
 
Re: small wires No Charles, that\'s quite wrong.

[ QUOTE ]
= voltage drop leads to increased amps.

As anyone with any electrical knowledge will know that = more wear, arcing etc.

[/ QUOTE ]Charles, I always get terribly confused by your posts as you change the title and use that as part of the message. If I have read your post correctly you have it the wrong way round! Small wires results in high resistance which leads to fewer Amps. And less arcing and less wear. Mind you, you get poorer performance and more energy loss, as anyone with any electrical knowledge will tell you /forums/images/graemlins/wink.gif

Englander and I 'squander' water at about the same rate -- about a tenth of the amount used by a typical household.
 
Re: small wires No Charles, that\'s quite wrong.

[ QUOTE ]
= voltage drop leads to increased amps.
As anyone with any electrical knowledge will know that = more wear, arcing etc.

[/ QUOTE ]
[ QUOTE ]

If I have read your post correctly you have it the wrong way round! Small wires results in high resistance which leads to fewer Amps. And less arcing and less wear. Mind you, you get poorer performance and more energy loss, as anyone with any electrical knowledge will tell you /forums/images/graemlins/wink.gif



[/ QUOTE ]

I think you need to brush up on your Ohms Law and physics !

The smaller the cross section of a cable will produce " volts drop" at a given length.

e.g. 12volts @ 12watts = 1amp, so lets asume 1volt of drop = 11volts @ 12watts=1.09amps. So my reckoning shows that's an increase !!! /forums/images/graemlins/wink.gif
 
Re: small wires No Charles, that\'s quite wrong.

[ QUOTE ]


I think you need to brush up on your Ohms Law and physics !

The smaller the cross section of a cable will produce " volts drop" at a given length.

e.g. 12volts @ 12watts = 1amp, so lets asume 1volt of drop = 11volts @ 12watts=1.09amps. So my reckoning shows that's an increase !!! /forums/images/graemlins/wink.gif

[/ QUOTE ]

No, it doesn't work like that! You need to go and brush up on your physics. Have a look on one of the basic electrical websites....I could explain it but frankly you would be best served by reading an article that has been written carefully, for beginners, and not just bashed out as a forum message. I think one of the books such as the 12V bible will cover this ground?
 
You must log in or register to reply here.

Other threads that may be of interest

MagicalArmchair
Servicing the fresh water pump of a d2-55A
Replies
0
Views
74
MagicalArmchair
MagicalArmchair
cyberkryten
We finally bought a boat - Merry Fisher 895s2
2
Replies
26
Views
746
Bouba
Bouba

Share this page

Top