Accumulator

[KYAirstream]

I installed one of those shurflo accumulators to go with my PAR water pump. I can't tell much difference other than the water pump will run for about 3-4 secs, then pause for about a second, and then run for 3-4 more seconds, etc. Before it would cycle on and off about every second or two. Is this all it's suppose to do? I guess I was expecting more water flow without the pump running.

[dkottum]

It's greatest use is to take up thermal expansion in the water system and prevent leaks and possibly damage to connections. It also functions as a shock absorber smoothing the operation of the system.

To have a large supply of water without the pump running frequently you would need a much larger accumulator. The pump would then run less but much longer. I've thought about it but our little Shuflo works well enough.

[crispyboy]

Have you adjusted the air pressure in the accumulator?

[Protagonist]

Originally Posted by KYAirstream

I installed one of those shurflo accumulators to go with my PAR water pump. I can't tell much difference other than the water pump will run for about 3-4 secs, then pause for about a second, and then run for 3-4 more seconds, etc. Before it would cycle on and off about every second or two. Is this all it's suppose to do? I guess I was expecting more water flow without the pump running.

An accumulator is merely a reservoir with an air bladder that can be compressed when water pressure is applied and expand when water pressure is released. When your system is operating at a relatively high pressure you have a very fast flow of water through an open faucet, and as soon as you shut off the faucet, the pressure builds up in the plumbing. In extreme cases, you can experience "water hammer" which is a noise carried through rigid plumbing as the pressure is instantly applied. The air bladder in an accumulator allows the pressure to be applied more gradually and quietly.

An accumulator will make little difference in how your pump runs, and in fact it will be more useful when you're hooked up to a relatively high-pressure municipal system, not when you're pumping from your fresh tank.

On a related issue, an accumulator is more useful if you have rigid plumbing— PVC or copper— than if you have the more flexible PEX.

[rmkrum]

If you don't use the standard Atwood water heater, like we do, an accumulator is kinda needed for a tankless water heater. The pump short cycles and makes a lot more noise when the accumulator or an air bubble in the Atwood is not there. The nice thing about the accumulator tank is that you don't lose the trapped air bubble.


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[mixedpuppy]

I find it most useful simply to prevent leaks from pressure changes during cold weather, which I was experiencing in various locations until I installed the accumulator. No leaks since.

[Siegmann]

Oh, and be careful of trying to get longer flow by upping the pressure charge. If I recall correctly, I think it was supposed to be 20 psi and I went to 30 psi, and busted the membrane.

If the pump cycling is really bothering you, and you have the space, there are somewhat larger (2 gallon) accumulators available.

[dkottum]

I think the Shurflo comes preloaded to 30 psi and that has worked well for us. Yes I can see how the membrane could break raising it too high, really no need to increase it that we have seen.

[Siegmann]

You got me thinking about that so I checked. Your 30 psi is fine, according to Shurflo.

http://legacy.shurflo.com/pages/Food.../911-378-P.pdf

Maybe I had gone to 40 psi. Can't recall.

[dkottum]

Thanks for checking, I wasn't certain but good to know.

[ROBERT CROSS]

There is a stedfast limit as to how much I can accumulate.....



Bob

[KYAirstream]

Originally Posted by Protagonist

An accumulator will make little difference in how your pump runs, and in fact it will be more useful when you're hooked up to a relatively high-pressure municipal system, not when you're pumping from your fresh tank.
.

My understanding from the manual is that the accumulator is installed right after the pump, which is a line separate from the city supply (in my case there is a check valve. ). So are you saying it should go in the supply line that both the pump and city supply share?

[KYAirstream]

Originally Posted by Siegmann

Oh, and be careful of trying to get longer flow by upping the pressure charge. If I recall correctly, I think it was supposed to be 20 psi and I went to 30 psi, and busted the membrane.

If the pump cycling is really bothering you, and you have the space, there are somewhat larger (2 gallon) accumulators available.

Did you hear it bust when you applied too many PSI, or did it just stop operating as it did before?

[Protagonist]

Originally Posted by KYAirstream

So are you saying it should go in the supply line that both the pump and city supply share?

It will work better that way, I think.

[Siegmann]

Originally Posted by KYAirstream

Did you hear it bust when you applied too many PSI, or did it just stop operating as it did before?

No sound. Probably just a tear. When I removed the air hose, a little water came out of the air inlet fitting. Clearly got water on the wrong side of the bladder. Oh, and it did stop operating as it had before.

[Stormalong]

New year gift for our 2015 25 fc. Purchased a 2.1 gallon expansion tank/accumulator at home depot. Installed under sink in bathroom. Put a tee on accumulator, one leg goes to cold water supply line. Other leg goes to cold water at faucet. What a wonderful upgrade. Water at galley runs nearly 15 seconds before pump runs. We can flush the toilet 4 times without running the. Pump.
Yes the pump runs longer when it does run, but flow rate is very uniform.
Most importantly my wife loves the home- like water flow.

[dznf0g]

Originally Posted by Stormalong

New year gift for our 2015 25 fc. Purchased a 2.1 gallon expansion tank/accumulator at home depot. Installed under sink in bathroom. Put a tee on accumulator, one leg goes to cold water supply line. Other leg goes to cold water at faucet. What a wonderful upgrade. Water at galley runs nearly 15 seconds before pump runs. We can flush the toilet 4 times without running the. Pump.
Yes the pump runs longer when it does run, but flow rate is very uniform.
Most importantly my wife loves the home- like water flow.

I did this in my old sob, but it was a 1 gallon tank from grainger. Worked well, but that was an old single speed basic pump. I have never felt the need with the AS with the variable speed pump.