Conditions under which fresh water pump should run?

Do you have an icemaker which could account for intermittent pumping?Beyond that, the most common causes would be air in the water line or a leak.

Some years ago I spent weeks trying to find a water leak causing cycling. I isolated it to the hot water circuit but could not find it. Finally, I found that it was the pressure relief valve on the water heater, which was plumbed overboard. Replacing that valve regained my sanity.

Have chased down a couple over the years. The two that were the most difficult to find:

Pressure relief valve on Hot Water heater. It was plumbed overboard, so no water anywhere in the boat. Finally reached the point of having trouble maintaining hot water. Had the valve replaced, solved the pump cycling problem.

The second difficult one was a wash down faucet on the bow that was inside a locker where lines were stored. Pushing the lines in were sometimes hitting the handle. I had checked it, was tight. But a day or two later, pump was cycling ( after the boat had moved and lines were taken in and out). We moved the lines after that.

I have never had a problem with a line rupturing. It has always been at a connection point or the manifold.
 
How often does it happen? Possible leak.
I will have to go searching for a leak. Not sure how often it happens as when I’m on the boat for long periods, so is my family so I would have to mandate a no water use policy to figure it out. I know it happens though. Last weekend, I was woken up Saturday and Sunday morning to the sound of the pump while everybody was sleeping.
 
Do you have an icemaker which could account for intermittent pumping?Beyond that, the most common causes would be air in the water line or a leak.

Some years ago I spent weeks trying to find a water leak causing cycling. I isolated it to the hot water circuit but could not find it. Finally, I found that it was the pressure relief valve on the water heater, which was plumbed overboard. Replacing that valve regained my sanity.
No ice maker but I will take a look at the hot water heater in addition to checking for leaks.
 
The accumulator will drastically slow the cycling during things like brushing teeth, washing hands. I have used the smaller one (24oz) due to space constraints, but the larger ones are even better in this regard. Better yet, you can install it anywhere on the cold water side of your plumbing (under a sink, in the ER, etc). It doesn't have to be at the pump to function properly

So when does the accumulator “call for” water from the pump? It seems like it would just constantly try to refill itself which would result in the same frequency of pumping. Thanks for the assist.
 
So when does the accumulator “call for” water from the pump? It seems like it would just constantly try to refill itself which would result in the same frequency of pumping. Thanks for the assist.

the accumulator has two sides: water and air, separated by a flexible diaphragm. The air side is pressurized to be near but just above your pump pressure switch minimum. When you open a tap the accumulator pushes water through the system so the pump doesn’t detect a pressure drop until the accumulator pressure drops. Then the pump kicks on and continues to supply water and refills the accumulator.
 
I think you can find it for about $1500. I have a spare (new in box) that I’ll let go for $1200.
I'll keep that in mind. I need to diagnose the potential leak, consider an accumulator and be sure I have room for what looks to be a much larger pump before going down that path.
 
How old is your fresh water pump?

When I was working on water leaks 2 years ago the pump would cycle pretty frequently. Use all your senses to try to find the leak. Most of mine had telltale sign in the bilge with a little dribble here and there. I did find one by using a piece of paper towel by wiping down a few fittings until I came across a wet one.

Believe it or not as soon as I fixed the last leak the pump just kept running building zero pressure so I had to replace the bottom end of the pump.

knocks on wood....... it's been leak free since.

Water leaks can be a pain in the butt so I have purchased a few spare 15mm push to fit fittings just to have on board if they pop up again.
 
An accumulator tank simply stops the fast/constant cycling of the water pump by adding a water reservoir and a bladder pressurized by compressed air. Once installed, the pump will cycle much less often when water is being used (as you are initially depleting the water from the reservoir). The larger the accumulator tank, the less frequently the pump cycles. It's better for the pump as a result.

I've installed one on every boat I've owned and can't speak of any downsides...
We need to “Sticky” this ..... this question comes up a lot
 
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Be careful putting a more powerful fresh water pump on if your boat is a few years old.

If you have been running a 40PSI pump and you change over to a 60PSI pump, could create some more leaks if the fittings, etc are a few years old.
 
Be careful putting a more powerful fresh water pump on if your boat is a few years old.

If you have been running a 40PSI pump and you change over to a 60PSI pump, could create some more leaks if the fittings, etc are a few years old.

That's a good point.

However my boat is 32yrs old and still has the original old grey pipe plumbing. The newer boats early 2000's should have pex, blue and red crimped piping. Which should not be an issue.
 
Shurflo has a few on the market as well for the RV's for less then $50.

Anyone use one of these?


https://www.homedepot.com/p/Shurflo...LUr3h5gendMzPnYTtpMaAl_2EALw_wcB&gclsrc=aw.ds

Any accumulator is better then no accumulator. But you need to match the accumulator to your pump. If the accumulator fills too quickly and reaches pump max pressure too soon you will still have pulsing. I did re-pressurize my accumulator when I put the new pump in, but to 40 psi.
 
Every time you turn off the water pump circuit you have the possibility of air getting into the water lines. I have not turned my water pump off in several years now... And have zero cyclings. After introducing NoFlex Digester into my head system I have had zero cyclings of the vacuum pump = Happy Camper !!!
 
Whoa. $2k at Fisheries. That’s pretty steep in comparison to the options.
Yes, these pumps are standard on Nordhavn, Fleming, etc. They also appear to be making their way into several Prevost conversion buses (Liberty and Marathon, I think).

I think you can easily “get by” with a solid Shurflo pump should you need to replace yours. They are all I have ever owned.

The Headhunter units are the only ones I’m aware that claim “virtual silence” and clearly silence must be made of gold.
 
This is my setup...I went to 55psi. It’s been in there for 4 years now.
979E215F-B581-4B38-B50A-E61CFF305C36.jpeg
 
How old is your fresh water pump?

When I was working on water leaks 2 years ago the pump would cycle pretty frequently. Use all your senses to try to find the leak. Most of mine had telltale sign in the bilge with a little dribble here and there. I did find one by using a piece of paper towel by wiping down a few fittings until I came across a wet one.

Believe it or not as soon as I fixed the last leak the pump just kept running building zero pressure so I had to replace the bottom end of the pump.

knocks on wood....... it's been leak free since.

Water leaks can be a pain in the butt so I have purchased a few spare 15mm push to fit fittings just to have on board if they pop up again.
Appreciate the guidance. It's the original pump, 13-14 years.
 

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