Fresh water tank

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LUVYAPOP

Veteran Member
Joined
Jan 23, 2019
Messages
43
Location
United States
Vessel Name
LUVYAPOP
Vessel Make
Chung Hwa Stinger custom
If anyone has knowledge in this matter, please help with suggestions. I had a JABSCO 3.0GPH fresh water pump with a small SHURflo 30psi accumulator. Now my understanding of how it's supposed to work is once the accumulator if full the pump shuts off. Pump turns on at system demand, correct? Well, it got to where the pump would not shutoff. I was told at West Marine the accumulator probably failed and to just remove it, don't need it. I bought a new JABSCO 4.0GPH water pump, removed the accumulator from the equation and the pump still runs continuously. The guy told me the pump shouldn't keep running. I have two wires, ground and power. Pump runs fine, but doesn't stop running. Do you all feel/think/know if I SHOULD have an accumulator back in the system? Thanks in advance.
 
The accumulator is there to stop the pump from running as frequently. It builds up water and when the pump hits the PSI that it is set to go off at the pump will turn off. When you turn on water the accumulator supplies water until the PSI runs down to the pump turn on pressure is hit. So the pump will run longer when water is demanded but it doesn’t turn on as soon the next time water is demanded. So you don’t hear the pump as often and the pump should last longer not having to come on as often. Why your pump runs continuously is another issue. Do you have a leak anywhere? I would leave the accumulator in the system. The running is from a different issue.
 
No leaks. Checked everywhere. I'm going to buy a new accumulator and install it. Thanks for the input.
 
Well plumbing isn’t my strong suit. I would find out why the pump is running before I put the accumulator back in, why add any more complexity to the situation. Once you get the running problem fixed then add the accumulator back in. At least that is what I would do...
 
I suppose that the valves in the pump could be bad, which would be unusual here since you have had the same problem with 2 pumps but if you have debris in your water tank the debris could be causing the valves to leak and the pump not build up to pressure. Is there a filter in front of the pump? Maybe a way to check would be unhook the plumbing system from the pump and put either a plug on the output side of the pump or a short section of pipe. Then see if the pump turns off. If it doesn’t then the pump is bad, maybe full of debris. I had a previous boat with a fiberglass tank that the gel coat broke down and clogged the pump. Replaced the tanks and put a filter in front of the pump after replacing the valves and my problem went away.
 
Comodave, I do have a filter set up before the pump. Keep in mind I just bought and installed the water pump yesterday. Not to say new stuff doesn't come out of the box bad, but it runs and I get water through the taps. I just drained and flushed my water tank last week. Keep in mind, the spicket on my fresh water tank is about 7" from the bottom of the tank and the tank has three chambers. I can only access the middle chamber so it is impossible to see if there is anything clogging there. I really don't think there is. I have a spare filter, I suppose I can go ahead and change it and try again. Thanks again.
 
Ok, sounds like you have done the right things... I don’t have any other ideas, maybe someone more knowledgeable about plumbing will chime in.
 
If anyone has knowledge in this matter, please help with suggestions. I had a JABSCO 3.0GPH fresh water pump with a small SHURflo 30psi accumulator. Now my understanding of how it's supposed to work is once the accumulator if full the pump shuts off. Pump turns on at system demand, correct? Well, it got to where the pump would not shutoff. I was told at West Marine the accumulator probably failed and to just remove it, don't need it. I bought a new JABSCO 4.0GPH water pump, removed the accumulator from the equation and the pump still runs continuously. The guy told me the pump shouldn't keep running. I have two wires, ground and power. Pump runs fine, but doesn't stop running. Do you all feel/think/know if I SHOULD have an accumulator back in the system? Thanks in advance.

The pumps were GPM, not GPH?
It depends on the design of the pump. On an accumulator, you have to have a check valve on most centrifugal pumps. If it is a low output, piston or diaphragm pump, you won't need a check valve. A check valve keeps the pressure in the accumulator when the pump shuts off. Piston and diaphragm pumps already have check valves as part of the pump design.

You have to have something telling the pump to shut off when it gets the accumulator tank charged to 50psi or something near that.

If your "guy" told you to buy a variable flow pump, they don't need an accumulator but run when you need water, pumping more water when you need more water or less to suit demand. They also extract a larger chunk of boat bucks from your wallet, and from what I hear, cause more problems.

Do you have a pump pressure switch? If not, find out where the old one went, or get a new one. Wire up the power into the pressure switch, and then wire the pressure switch to the pump. The pump will turn on when the pressure switch says there is less than 50 PSI (or whatever the low limit - cut-on limit is set) and when the pressure builds up to 50 PSI the high limit switch is closed which turns off the pump.

Some pressure switches are external, wired up outside the pump, and piped into the output of the accumulator so you get the tank pressure. If your pump has a pressure switch, (some do, some don't) then it senses pressure off the output side of the pump. This type won't work if you have the check valve between the pump and the accumulator.

Which Jabsco pump did you buy? Model # please...
 
No leaks. Checked everywhere. I'm going to buy a new accumulator and install it. Thanks for the input.

Its possible you need to pump up the pressure in the accumulator with a bicycle pump. Naaa, I don't really know.
 
I think that if the accumulator was not up to pressure it would act just like it was not there. The pump would come on when water is demanded and go off when the system including the accumulator filled up.
 
Pump doesn’t turn off with all outlets closed.

Things that cause pressure pumps to not turn off.

Leak on output side of the pump - you already checked for leaks.

Bad valves in the pump - you installed a new pump and have a filter on the intake side of the pump. Check the filter anyway. Maybe crap is getting through?

Bad pressure switch - you installed a new pump.

Air getting in on the suction side - shouldn’t cause continuous running and air would spit out the faucets when open.

Lack of or a bad accumulator tank shouldn’t cause continuous running with the faucets closed.

It’s unlikely but my best guess is you missed a leak. It would have to be a fairly large leak as a small leak would just cause the pump to cycle on and off.

Test your old pump. Just put a couple of hoses on it. Run the intake hose to a bucket of water. Put a hose nozzle on the output side. Power it up. It should run a few seconds and stop. Open the hose nozzle and it should start. You might have to open the nozzle and let the air out of the system before it will work right.

What are the model numbers of your old and new pumps?

This is a puzzler. I’m looking forward to hearing what you find.
 
LUVYAPOP...
HopCar cover the subject very well.

Have you tried shutting the pump breaker off and hooking up dockside water? What happens? Flow or no flow with all outlets shut off?
Has a previous owner plumbed in a valve from dockside water to fill fresh water tanks from dockside vs external hose & deck fill? I don't think any mfg would do this but know owners that have (I'll plead the fifth)
Is your head raw or fresh water flush?
One other very puzzling event that had me stumped for awhile on previous boat.
Is your water heater connected to your engine for heating when underway? If so, coolant overflow if closed system.
I had this on a prior raw water cooled gasser and the water heater engine heat coil failed (improper winterization by the yard) and water was back flowing from my fresh water system to engine and out exhaust. In a closed system it would go to the overflow tank.
 
  1. One of the prime rules of troubleshooting: Don't overlook the obvious. You ARE connecting the pump per the instructions, and that pump DOES have an integral switch? A model # would tell the tale. If the pump you bought doesn't have a switch, you're chasing your tail.
  2. You should have a strainer, not a filter, on the inlet side of the pump. The filter should be on the pressure side. Some filters will deform and block flow if they're installed on the suction side, it's unusual, but entirely possible. Your problem, however doesn't sound like it's that issue.
  3. I'd get an accumulator into the system. It doesn't have to be one of those very expensive "marine" accumulators, it can be an ST-5 expansion tank that's available at the big box stores. It will be much less costly, and it will be more effective, and last just as long. The expansion tank is tee'd into the pressure side, downstream of the pump. Anywhere in the cold piping system, it does not have to be physically near the pump. That said, I doubt that the accumulator has anything to do with the pump not shutting off.
  4. To eliminate a problem with the system, isolate the pump. Pull a fitting and plug it near the pump, then see if it shuts off. That will eliminate the piping. If the pump continues to run on a closed discharge, your control is either non-functional or non-existent. See #1 & what HopCar suggested to test the pump alone, out of the system.
  5. I'd pull the filter element for testing, then at some point, relocate the filter downstream of the pump where it belongs, and provide a strainer on the inlet side.
 
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STUBONES99, I installed the JABSCO 82400-0092 Par-Max Plus water pressure sysytem pump 12v, 4 GPM. I took apart the accumulator today and I'm thinking that was the problem bc the bladder inside wasn't seated properly. The edge of the bladder which fits in a groove in one end of the housing was flat. I ordered a new accumulator. Will install and let you know what happens. There's no leaks, even small ones. Water tank is full, but still have to change the water filter upstream from the pump inlet.
 
Hopcar, the new pump is a JABSCO 82400-0092 Par-Max Plus water pressure system pump 12v, 4 GPM. The old one was a 3 GPM JABSCO. When I get the accumulator in I'm going to install it as per the original setup. Water tank, filter, pump,accumulator. The old one shutoff after the accumulator reached pressure. I remember leaving the pump switch on all night then hear it run after a faucet was opened. Once closed the pump would shutoff automatically.
 
Maerin, Like I told Hopcar, when I get the new acc in I'm going to install it as per the original set up. Water tank, filter, pump, accumulator. The old one shutoff after the accumulator reached pressure. I remember leaving the pump switch on all night then hear it run after a faucet was opened. Once closed the pump would shutoff automatically. If that doesn't work, I'm going to try some of your suggestions. Mahalos for your input.
 
BACCHUS, I can run both dock water and use fresh water tank separately. The only common denominator is the water heater, but only at the cold water inlet. I have a compost toilet, which I absolutely love, so no lines there. The water tank is filled through a filler neck. My water heater is heated electronically. Not connected to engine. I don't take the boat out and stay on it long enough to connect to the engine. The old pump shutoff after the accumulator reached pressure. I remember leaving the pump switch on all night then hear it run after a faucet was opened. Once closed the pump would shutoff automatically.
 
STUBONES99, I installed the JABSCO 82400-0092 Par-Max Plus water pressure sysytem pump 12v, 4 GPM. I took apart the accumulator today and I'm thinking that was the problem bc the bladder inside wasn't seated properly. The edge of the bladder which fits in a groove in one end of the housing was flat. I ordered a new accumulator. Will install and let you know what happens. There's no leaks, even small ones. Water tank is full, but still have to change the water filter upstream from the pump inlet.


Note, you may have to adjust the pressure in the accumulator. Jabsco's recommendations can be a bit baffling, but it'll likely come with about 10 psi... whereas you'll want to increase that to right around (just under, IIRC) the pump's cut-in pressure.

-Chris
 
Okay HopCar, Here's what I did. I changed the filter in hopes the water would stop coming out foamy. That's another issue I have, but as far as the pump running, for some reason, when I opened the shutoff valve that isolates the dock water from the fresh water tank, the pump would shut off after accumulator reached psi. Here's a photo of what I'm referring to.
The yellow arrow is my filter which is directly after water tank and before water pump, green arrow. Blue arrow is accumulator, red arrow is T fitting that joins cold water lines from water tank and dock water. Purple arrow is shut off valve on cold water line coming from dock. What I found out is when I had the shutoff valve closed, the pump would NOT shut off. I opened the shut off valve and the pump shut off after accumulator filled. Weird. Anyway, pressure is still weak. Think I should fill accumulator a bit more?
 

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Water system

Okay, here's the ongoing issue with my water system. In the photo is my pump(green arrow), accumulator(blue arrow), Filter(yellow arrow), Shutoff valve on water line coming from dock water(purple arrow), T fitting that joins tank water and dock water(red arrow) that leads directly to the water heater cold inlet. Here's what I found. I had the SOV closed at the time when I installed the new accumulator, the new pump wouldn't shut off. Then I opened the SOV and the pump shut off after accumulator filled. Would anyone know why that happened?
Now I had a post earlier about foamy water. Some of you asked about a leak. I could not find any leaks in the system. However, I did notice when the pump is on, I noticed air in the hose between the filter and pump. Could that be bc there's too much hose for the water to travel from the water tank to the filter? Now when I run the water from the dock, pump switch is off, water tank closed, water from the kitchen sink and outdoor shower comes out foamy. Have to let it run for about five minutes until it starts to come out clear. It happens the same way using the water tank. Only common denominator is the water heater. Could that be the issue? If I went to a tankless, any of you think that would fix the issue? Thanks for input in advance.
 

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First, is it really foam, like suds that take some time to dissipate, or aeration which would be gas incorporated in the water as it comes out the faucet but dissipates immediately? If it really is foam I'd suspect something in the water as pure water should not foam. Have you had winter antifreeze in the system? This could be a long shot, but I find the RV antifreeze causes foaming and is extremely hard to get out of the hot water heater. The symptom of residual antifreeze is some foaming and of course the taste.
 
That really isn’t electrical wiring above the plumbing that the plumbing is tie wrapped to is it?
 
First thing, your filter should go after your pump and not before. These are filter that should be pressurized by the pump for the water to go through and not on the suction side. This should explain why your pump don't stop when your dock water valve is closed. Pump try to suck in water but your filter does not allow it to go through.
Second you should put a checked valve between your dock water line and your accumulator tank. When using dock water you do not have to pressurize the accumulator, nor the pump. If your pump stop when the dock water valve is open this is because dock water pressurize your pump so the pressure switch stop the pump.
Last, I am sure you can find a better way to hold your water hoses than using some strings over your electric wires.

Edit: You should also double clap your hose so to reduce risk of pop out on any fitting. Believe me this is not a thing you want to see occuring when you are on dock water.

L
 
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Everything is more efficient using pressure instead of vacuum. The best you can ask for on a vacuum is atmospheric pressure causing an imbalance and whatever you're pumping will go toward the lower pressure zone.

When you use pressure, you force the liquid, under pressure through filters and everything else.
 
See the red button on the filter. Used to remove air when filling. The filter is on the suction side of the pump. When the pump starts, the path of least resistance is thru the red button. It gets pulled down slightly, air enters, and when the air hits the impeller it becomes millions of little bubbles. The pump loses efficiency with all those bubbles and may not be able to reach shut off pressure. If you have an accumulator tank, it's probably half full of air on the water side and not operating correctly. It can cause the pump to have short cycles.






 

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And organize/secure those hoses, that's a Rube Goldberg mess.
 
The pressure is pre set and I don’t think,adjustable...I have sold literally thousands of these pumps during 20 years in the RV industry..mostly shut-flo but all other makes too. Accumulater not necessarily needed...the only reason we would sell an accumulator tank was if you had air ingress somewhere that caused the line to actually “chatter”. The tank accumulates the air and solves that issue...it’s the same for boats. If it your system works without an accumulator then you don’t need one...other than that your pump sounds like it is doing what it is supposed to. In 20 years I think I sold 2 of those tanks only.
 
See the red button on the filter. Used to remove air when filling. The filter is on the suction side of the pump. When the pump starts, the path of least resistance is thru the red button. It gets pulled down slightly, air enters, and when the air hits the impeller it becomes millions of little bubbles. The pump loses efficiency with all those bubbles and may not be able to reach shut off pressure. If you have an accumulator tank, it's probably half full of air on the water side and not operating correctly. It can cause the pump to have short cycles.


^^^^ This ^^^^


Precisely right. Move the filter to where it belongs, your problem will resolve itself.



Clean up the piping and wiring.
Add a check valve in the tee'd line to the pump- red arrow. It would appear in the bottom part of the tee in the photo, with the arrow pointing toward the upper part or straight through leg of the tee. Purpose is to prevent dock water flow from reaching the pumps, you don't want the internal checks in the pump to serve that purpose, that's not their design function.

The reason really good tradespeople make their installs neat and "pretty" has more to do with function than aesthetics. Neat, orderly installs are way easier to follow visually, it makes troubleshooting much easier, and you eliminate lots of problems before they have a chance to become problems.
 
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