I used an accumulator until last year when the tank started leaking. I'll never go back.
Domestic water accumulator purging
- Thread starter Skipper
- Start date
This isn’t a one solution kind of thing, depends on your boat and your usage. If you have a small boat with a few taps and you don’t need a domestic-type water system you can skip the accumulator, use a cheap low flow pump and be fine. Your water will pulse when multiple taps are in use and your pump will cycle more often without the stabilizing effect of an accumulator. If you have a larger cruiser where there is a probability that some one will be using the galley sink while someone else is showering you definitely want a suitably sized accumulator to smooth out the flow. You can get multi-tap flow rates with 5 and 6 gpm pumps but the cost benefit would be in favor of a 2 gallon accumulator instead of a $400 pump. Small accumulators serve a different purpose than larger; they are there to reduce pump cycling, reduce pulsing, and extend pump life. Larger accumulators give you a “home like” water system experience.
That makes sense. I'm used to them in my home design/building field. Often we're using them for expansion of the plumbing system, especially on town pressure where check valves are in place. A big water heater expands a lot of water and it needs a place to go.
On my boat, I worry about that thermal expansion if we're motoring for many hours. There's always the T&P valve on the tank, but I'll draw off a bit of water in those rare instances(we don't motor long distances often, anymore).
Those tiny boat accumulators that most people use, look too small to have much effect on evening out the flow if two faucets are used. The bigger ones would be great. I find with low flow fixtures, with a medium duty pump, the flow is even. The pump keeps up, no problem. Two fixtures and then the flow gets cut down. But I like that, when it comes to fresh water on the boat.
Back to homes, accumulator tanks are one of the prime reasons, I call a plumber. They don't seem to last very long.
We have 3 sinks and a shower with 2 people aboard, so it is very unlikely that all the faucets will be running at once. And it is a simple task to wait until someone is done with one sink before opening another faucet. I suppose with a larger boat with more people aboard, this could be more of an issue. For us, the single pump works well.
The other thing about an accumulator is that it can cover up symptoms of a slow leak in plumbing or in the pump's check valves. Rather than the pump cycling frequently or in the middle of the night the accumulator makes up for the lost pressure. This may be a feature or a bug depending on your perspective.
The "Trapped Air" Accumulator or what is termed "pulsation damper" industrially is the BEST.
Low maintenance!
Just introduce air, periodically, and if the accumulator is vertical then air traps in top.
Adapt a Shrader valve to your bleed screw @Skipper and pumps some air in 10-30 psi.
http://www.x2industries.com/other-f...-air-inflation-valve-p-5896.html#.WrYEj2aZNTY
With a small bicycle pump.
OR
If you can open your Accumulator, stuff this, partially inflated, inside it.
https://www.amazon.com/Replacement-...rd_wg=uaWLE&psc=1&refRID=WG1CJHKR64VF1Z7SNDE8
There are smaller diameter ones, but it is made of Butyl Rubber and not EDPM rubber, like the Jabsco Diaphragm type bladders. Butyl rubber may make "garden hose" flavored water.
OR
Install a water drain valve on the input line, open vent, open valve and drain the accumulator.
Jim...
PS: I install just a copper Tee [accumulator] at each house sink and lavatory to stop pipe vibrations when rapid faucets closing would causes a "water hammer".
PSS: For those of you with Jabsco type diaphragms that leak, use the Shrader valve and inflate it to 30 psi, periodically, if it is vertical.
Low maintenance!
Just introduce air, periodically, and if the accumulator is vertical then air traps in top.
Adapt a Shrader valve to your bleed screw @Skipper and pumps some air in 10-30 psi.
http://www.x2industries.com/other-f...-air-inflation-valve-p-5896.html#.WrYEj2aZNTY
With a small bicycle pump.
OR
If you can open your Accumulator, stuff this, partially inflated, inside it.
https://www.amazon.com/Replacement-...rd_wg=uaWLE&psc=1&refRID=WG1CJHKR64VF1Z7SNDE8
There are smaller diameter ones, but it is made of Butyl Rubber and not EDPM rubber, like the Jabsco Diaphragm type bladders. Butyl rubber may make "garden hose" flavored water.
OR
Install a water drain valve on the input line, open vent, open valve and drain the accumulator.
Jim...
PS: I install just a copper Tee [accumulator] at each house sink and lavatory to stop pipe vibrations when rapid faucets closing would causes a "water hammer".
PSS: For those of you with Jabsco type diaphragms that leak, use the Shrader valve and inflate it to 30 psi, periodically, if it is vertical.
That's some great info, thanks.
For me/my setup, the easiest thing in the world will be just letting the water tanks run dry instead of refilling them when low. Then leave the pump on with the faucet open for a half a minute, sending air to the accumulator to displace water in there. Done. Performance returned. Then refill water tanks.
For others, depending on config etc, I think the drain valve idea is a good one.
Mainsail's buy list is good too but I think I actually prefer the no-diaphragm version. I mean, the thing is 34 years old and works the same as when it was new. Never have to worry about a failed diaphragm.
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