Accumulator Tanks

Jurgen

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Hi all, both SWMBO and I are getting pretty annoyed with the noisy water pump on our boat so are considering fitting an accumulator tank.

Do these significantly reduce the pump noise and if so what is a sensible size tank to install?

We tend to shower on board so one would imagine that bigger is better?

Regards

Andy
 
As far as I know the tank just smoothes out the flow, and stops the water coming out in a pulsating flow, particularly at lower flows. In the case of a shower I doubt that the pump would work any less. The only time the pump might not come on is if you just run the tap for a second or two.
You would need to check your pump as some are designed to smooth out the flows with a valve arrangement in the pump and these should not be used with an accumulator.
I think that if you are looking for less noise from the pump, fitting an accumulator will not help much!!
 
Our pump was getting noiseier and it wasn't long before it packed up (rusted up inside).I replaced it with the same model.The instructions said no accumulator tank was needed.I can see why, its very quiet and does'nt pulse.The make is a Flojet R4405-143a bought off fleabay about £115 not cheap but worth it.
 
depends on how the OP defines noise. For me the pulsating thing when washing my hands is V.annoying, but for sure no matter how big the tank the pump will still work the same way..

and if OP don't mind a slightly OT question, has anyone fitted domestic CH expansion tanks in a boat? You know the red 5-10lt ones used in CH systems for stabilising the hot water pressure/flow within the pipes/radiators etc.

A 800ml "proper" marine accumulator costs close to to 100euro whereas a 10 or 20lt CH one, costs 25euro or so, that's a SERIOUS price difference. Please don't tell me it's mild steel and wont weather well in a boat, I can throw it in the skip every 5yrs and still be much better off. Any reason we cannot /should not use them?

cheers

V.
 
As already mentioned it does not reduce the noise the pump makes, however it does allow you to open a tap and allow flow without the pump always coming on. I fitted one to my S28 and I can fill about a litre of water into the kettle without any pump working, however I had to remove the pressure switch side of things from the water pump, (a rubber washer and a spring) a very helpful man at Jabsco told me what I had to do regarding that.
 
An accumulator tank can reduce the amount of time a pump runs as it will provide the pressure for quick squirts of water from the tap. However the pump will have to build up the pressure again and will still be noisy.
It might be more effective to isolate the pump from the boat as much as possible to prevent the transfer of vibrations through the vessel. Make sure it is connected to the pipework with flexible hoses. Even beter if these have a loop next to the pump to act as shock absorbers. Alo think about the pump mounts. Look at sprung or rubber mounts to isolate the boat from vibration. You can make a resilient mount yourself by mounting the pump to a plywood board then mounting an identical plywood board to the boat, then join the two boards together with four pieces of 1"-2" diameter rubber hose.this hose should be reinforced type strong enough so the weight of the pump will not flatten the hose between the boards. Each rubber hose should be bolted to each board through its side walls using m6/8 bolts, nuts and washers. The four hose sections then act as springs and remove the transfer of vibration and noise.

I hope that makes sense?
 
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Our pump has been noisy for the best part of a year and as it was like this when boat purchased, i assumed thats the way it was!
Until it died and new one fitted, whilst not total silence its much quieter.



Lynall
 
An accumulator tank can reduce the amount of time a pump runs as it will provide the pressure for quick squirts of water from the tap. However the pump will have to build up the pressure again and will still be noisy.
It might be more effective to isolate the pump from the boat as much as possible to prevent the transfer of vibrations through the vessel. Make sure it is connected to the pipework with flexible hoses. Even beter if these have a loop next to the pump to act as shock absorbers. Alo think about the pump mounts. Look at sprung or rubber mounts to isolate the boat from vibration. You can make a resilient mount yourself by mounting the pump to a plywood board then mounting an identical plywood board to the boat, then join the two boards together with four pieces of 1"-2" diameter rubber hose.this hose should be reinforced type strong enough so the weight of the pump will not flatten the hose between the boards. Each rubber hose should be bolted to each board through its side walls using m6/8 bolts, nuts and washers. The four hose sections then act as springs and remove the transfer of vibration and noise.

I hope that makes sense?

I can confirm that works as the bulk of the noise my pump used to make was due to vibration. As soon as I fitted it to a piece of wood with some rubber backing the noise all but disappeared. I also fitted an accumulator tank (1 ltr I think) and that stop the flow pulsating, and so now I can never hear the pump and the water flows smoothly.
 
and if OP don't mind a slightly OT question, has anyone fitted domestic CH expansion tanks in a boat? You know the red 5-10lt ones used in CH systems for stabilising the hot water pressure/flow within the pipes/radiators etc.

A 800ml "proper" marine accumulator costs close to to 100euro whereas a 10 or 20lt CH one, costs 25euro or so, that's a SERIOUS price difference. Please don't tell me it's mild steel and wont weather well in a boat, I can throw it in the skip every 5yrs and still be much better off. Any reason we cannot /should not use them?

cheers

V.
You shouldn't use the red ones as they are designed for lowish pressures on central heating circuits. It is fine however to use the blue or white ones intended for domestic hot water cylinders. I have a Jabsco 1 litre accumulator next to the pump and an 8 litre pressure vessel next to the calorifier. Hardly even know when the pump is running. Prob mainly due to isolating rubber fixings on the pump under the rear deck.
 
Hi all, both SWMBO and I are getting pretty annoyed with the noisy water pump on our boat so are considering fitting an accumulator tank.

Do these significantly reduce the pump noise and if so what is a sensible size tank to install?

We tend to shower on board so one would imagine that bigger is better?

Regards

Andy

Ive just done a mod on E4 to quieten it. Take the pump off the bulkhead and mount it horizontally. Alongside or just aft of the calorifier for you. Extend the pipes with push fit fittings and plastic pipe.

Virtual silence :).
 
Ive just done a mod on E4 to quieten it. Take the pump off the bulkhead and mount it horizontally. Alongside or just aft of the calorifier for you. Extend the pipes with push fit fittings and plastic pipe.

Virtual silence :).

Thanks Mark, will combine that with the rubber mounts as suggested by others. After reading the advice of others isolating the pump seems o make a big difference to the noise.

List of winter jobs has just got bigger :mad:
 
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