really silent pressostatic pump for fresh water circuit?

[vas]

hi,

the diaphragm pumps I have on board MiToS (3 different ones!) do their job pulsing badly the water along the pipes. I do have water everywhere, but all this pulsation creates two problems:

A. outlet from the faucet in the galley sink is rather small, so water pisses out at extreme velocity spilling all over the place and regularly splashing on ppl siting on the sofa beside and under it (having jumped over 40cm from the sink bottom...) A bit more and I could use it as a waterjet

B. water pulsing in the polystromatic 15 and 18mm hard pipes i've used means that pipes pulse, hitting the bulkheads or frames making v. annoying noises. Similarly annoying and loud to flushing the loo...

So, looks like I have to get a replacement pump and I assume it must NOT be a diaphragm one.
Are there any suggestions (please not silly suggestions for 1000quid worth of double pumps, accumulators, etc
FWIW, I do have a 3lt (or thereabouts) accumulator (not of much help tbh...
and again fwiw, I have mounted the pump on rubber mounts, washers you name it!

cheers

V.

 

[rafiki_]

Can't help with this one Vas, but worth a bump.

 

[westernman]

May be the problem is with the pressure accumulator - it is perhaps no longer accumulating (e.g. membrane leaking).
You should not see the pulses - they should be absorbed by the accumulator which should give you a constant pressure.

 

[rustybarge]

This might fit the bill ...


http://www.westmarine.com/buy/jabsco--v-flo-variable-speed-pump-5-0--11898681

 

[westernman]

This might fit the bill ...


http://www.westmarine.com/buy/jabsco--v-flo-variable-speed-pump-5-0--11898681

Actually I think you need this rather than the above:-

http://www.westmarine.com/buy/johnson-pump--accumulator-tank--11006996?recordNum=5

 

[kashurst]

I think your accumulator is knackered, the diaphrams split inside.
try this one, I have the same one, flow is lovely and smooth now
http://www.asap-supplies.com/eu/dom.../hotpot-accumulator-and-expansion-tank-520605

 

[rustybarge]

Actually I think you need this rather than the above:-

http://www.westmarine.com/buy/johnson-pump--accumulator-tank--11006996?recordNum=5

V-Flo Variable Speed Pump 5.0

This pump employs solid-state electronics to control water system pressure by altering motor speed as demand changes. The result is efficient and quiet delivery of water to your galley’s tap or shower without a need for an accumulator tank.

2 birds with ....

 

[jimmy_the_builder]

I think your accumulator is knackered, the diaphrams split inside.
try this one, I have the same one, flow is lovely and smooth now
http://www.asap-supplies.com/eu/dom.../hotpot-accumulator-and-expansion-tank-520605

Easy to test for a duff accumulator - if when you press the Schrader valve you get water instead of air, then you know the diaphragm has failed.

 

[vas]

Thanks guys,

the accumulator if fine, thank you. Less than a year old and used on two and a half tankfulls (say 1300lt of water)
However, it is a domestic product without the marine markup. It's not the typical red ones for CH systems, it's a blue for drinking water (although I don't drink from the tank)
Now the point here is that maybe it's not setup at the right pressure, that I can believe. Anyone care to mention what pressure my accumulator should be set/rather pumped up?

The whole point of the thread was if there's a cheap and cheerful NON DIAPHRAGMATIC fresh water pump I could use.
Don't think I'll stretch up to 300quid for one tbh...

cheers

V.

 

[matt_lake]

Thanks guys,

the accumulator if fine, thank you. Less than a year old and used on two and a half tankfulls (say 1300lt of water)
However, it is a domestic product without the marine markup. It's not the typical red ones for CH systems, it's a blue for drinking water (although I don't drink from the tank)
Now the point here is that maybe it's not setup at the right pressure, that I can believe. Anyone care to mention what pressure my accumulator should be set/rather pumped up?

The whole point of the thread was if there's a cheap and cheerful NON DIAPHRAGMATIC fresh water pump I could use.
Don't think I'll stretch up to 300quid for one tbh...

cheers

V.

You need to check your pump spec. The accumulator pressure should be 2-3 psi below the cut-in pressure of the pump. I'm guessing here but the picture of your acc tank looks to be only a few litres. I would expect to see a bigger acc tank on a boat as big as yours.

 

[kashurst]

these make a good non pulsing water pump, combined with a separate pressure switch (whale do one)
http://www.asap-supplies.com/eu/23680-4003-jabsco-pump
I will try and see what pressure my accumulator is in the next day or so, I think its marked on it.

 

[kashurst]

hi Vas, just checked my accumulator, its pressurised to 19 psi, hope that helps

 

[vas]

hi Vas, just checked my accumulator, its pressurised to 19 psi, hope that helps

thanks, now I got to find a way to measure the pressure on my tank, a tyre pressure gauge should do! and I got to fit a pressure gauge on the circuit to measure the pressure achieved as the pressostatic thing on the pump has a screw that you turn and alter pressure (that stops the pump, ie. operating system pressure)
Needless to say that I've played with both systems

cheers

V.

 

[kashurst]

to measure the air pressure in the accumulator, use a tyre pressure gauge, but I think you need to disconnect the accumulator from the water supply first and empty it.

 

[westernman]

It could be that the pressure switch on the pump is sticking - or that the pump is way over sized compared to the accumulator. You might try adjusting the pressure at which the pump kicks in and cuts out.

 

[JerryHawkins]

I have an earlier version of this: https://www.jabscoshop.com/marine/p...-vflo-constant-pressure-water-system-pump.htm . No accumulator required (save a lot of space!), very quiet and smooth water delivery.