• Untitled Document

    Join us on March 29rd, 7pm EST

    for the CBEC Virtual Meeting

    All EYO members and followers are welcome to join the fun and get to know the guest speaker!

    See the link below for login credentials and join us!

    March Meeting Info

    (dismiss this notice by hitting 'X', upper right)

Accumulator Question

Christian Williams

E381 - Los Angeles
Senior Moderator
Blogs Author
For the past few years my fresh water pump has cycled more and more frequently, until now the pump runs whenever a faucet is on.

I figured, time for a new accumulator. Mine was manufactured in 1997, and likely the bladder was worn out. (Hereʻs how accumulators work: https://www.youtube.com/watch?v=RMDE5v3ouN8 )

However, when I put a bicycle pump gauge on the old Shurflo Model 181-203, it read 25 pounds--which is ballpark for the 20 PSI intended.

I let the air out. No change. I put in 50 psi. No effect on the pump, which stayed on all the time.

So, before I buy and install a new accumulator, whatʻs going on here? Is the issue not the accumulator at all?

Also, my Jabsco PAR-MAX4 pump is famously noisy, which may exacerbate the issue.

ATTACH=CONFIG]27274[/ATTACH]
 

Attachments

  • 1-accumulator Ericson 38 .jpg
    1-accumulator Ericson 38 .jpg
    77.8 KB · Views: 216
Last edited:

Parrothead

Member III
Before buying anything I recommend removing the tank, draining it of all water and remounting it 90° clockwise to its current orientation. You want the tank to be above the water hose connections for air retention. It sounds to me like your tank has filled with water.
 
Last edited:

Kenneth K

1985 32-3, Puget Sound
Blogs Author
Maybe check the shutoff pressure switch on the pump? See how high a column of water it will pump up a clear hose (or hold your thumb over the hose) to see if it will build up more than just 1 or 2 psi before shutting off.

Seems like the accumulator wouldn't be doing anything (storing any pressure) until the pump pressurizes the lines to a higher pressure than the air pre-charge in the accumulator.
 
Last edited:

Merrimist

Hammy, 'Merrimist' E38 in sunny Bda
For my mind, you may possibly have a worn bladder in your accumulator. i.e. a hole in the bladder.
Dependent on age of the accumulator bladder, a hole in the bladder is not unusual. The tests you describe above would give you the results you note in the post as if the bladder holed, it is not storing any pressure but if bladder is holed, it is now acting only as a reservoir at same as pump discharge pressure up to the tap. As soon as you open tap, pressure drop, pump starts.
In effect if you were to remove the accumulator, you would have the same symptoms you describe.
I suggest two options depending on spares available, remove the accumulator, dismantle and fit new bladder, charge when accumulator when system is at zero pressure, put system back into service, and presto!
Or purchase a new accumulator.
Thats my sixpence in the ring FWIW

Hammy in the Med.
 

Christian Williams

E381 - Los Angeles
Senior Moderator
Blogs Author
Thanks for the recommendations and theories.

I concluded the problem was with my expectations, not the accumulator.

My pump goes on at 20 psi and off at 40 psi. As recommended, I set the accumulator pressure to 18/19, by bicycle pump gauge.

The noise of the pump is indeed reduced somewhat, maybe 30 percent. The pulsing is reduced maybe 20 percent.

My interest in further massaging my $40 plastic accumulator has dropped to zero percent.

The pump is gonna run most of the time, no matter what. I donʻt have room or need for a household-style accumulator tank big enough to make a difference.

The RV guys are the experts on these things, and my conclusions are based on their experience.
 

kmac

Junior Member
Most of the newer fresh water pumps don't require an accumulator tank. The purpose of the accumulator tank is to eliminate water pulsing, not to make the pump run less. The newer multi chamber pumps are smooth enough without the accumulator.
 

RCsailfast

E35-3 Illinois
Have been following this old thread. Having bypassed the water heater for winter I noticed the pump doesn’t run too long if any after shutting off the sink. After reconnecting the heater it takes a long time to stop.
The boat is using the heater as an expansion tank. You have to be careful turning on the cold faucet after running the engine as really hot water comes out.

In a a perfect world there should be a check valve on the heater supply and an accumulator just after the pump.
Too many other projects to address this nuisance.

Nice part art is the pressure holds for a long time with a 6 gal water heater
 

GrandpaSteve

Sustaining Member
Have been following this old thread. Having bypassed the water heater for winter I noticed the pump doesn’t run too long if any after shutting off the sink. After reconnecting the heater it takes a long time to stop.
The boat is using the heater as an expansion tank. You have to be careful turning on the cold faucet after running the engine as really hot water comes out.

In a a perfect world there should be a check valve on the heater supply and an accumulator just after the pump.
Too many other projects to address this nuisance.

Nice part art is the pressure holds for a long time with a 6 gal water heater

I added a check valve at the input of the water heater. That works good on my boat with no accumulator. Also no super heated water from the cold side after motoring.

https://images.app.goo.gl/jekM46jEMiTNA3oZ7
 

Kevin A Wright

Member III
Hey Christian,

Having just finished replacing the 35 gallon accumulator on my home water system I was surprised to see one on the boat and it being that small. The volume on that is so small I'm not sure it would properly be called an accumulator. More like a wide spot in the line to reduce pulsing from your pump. Shouldn't have much to do at all with how often your pump goes on and off. Sort of like putting a capacitor in line to smooth out your power supply.

Other trick to remember, when you are checking the pressure on these things it needs to be done with the pump off and the line depressurized. Otherwise you are just fooling yourself. But yes 2psi below your pump kick on setting is the place to be.

Kevin Wright
E35 Hydro Therapy
 

Christian Williams

E381 - Los Angeles
Senior Moderator
Blogs Author
Just to beat this to death, the pump I have is a Jabsco Parmax4 36020. It's a constant-speed pump. "When a fixture is opened, the pump instantly begins operation to provide a smooth constant flow from tank to faucet. " Jabsco says an accumulator isn't needed unless multiple filters cause pulsing. Mine doesn't pulse. The pump is intended to run all the time when water is commanded.

Jabsco also makes a variable speed water pump. It's a diaphragm pump that varies the pump speed according to demand, for theoretical more constant flow. It costs twice what the constant speed pump does, however on WM the reviews are terrible.

Accumulator was not my problem.
 

David Grimm

E38-200
I have a Jabsco 31395 Series, PAR-Max 2.9 Water System Pump, Dry Running
It runs quiet and was only 95 bucks on Amazon. No accumulator in the system. Have you checked the tank vent?

Dave
 
Top