Fresh water leak

[moonshadow]

I am copying this over here from my post in general section.
Hello. On my 2014 SO469 I am trying to track down what I think is a fresh water leak. The symptom is that the fresh water pressure pump will cycle a bit about every 15-20 minutes. So far I have looked at the obvious places. Deck shower, all water taps above and below the fittings. All showers. Electric toilets. Not much left except for a leak somewhere along the tubing hidden away. The bilges don’t seem to offer help. All is either salt water or rain/condensation water.
Has anyone had a similar problem and found a source hidden away?
I also wonder if there might be a problem in the pump or pressure switch? Changing feed tanks did not change the situation.
Thanks for any suggestions.
Paul

[Zanshin]

I spent days searching for my leak, I had the same symptoms with the pump cycling and seeing a bit of water in the bilge. All I could determine was that it seemed to be coming from the starboard side. The internal couplings on my Jeanneau are "John Guest" type and I finally found that there was a slow leak at a T-Junction going to the washing machine, hidden away in the depths of the boat.

If your pump cycles but no water ever shows up in the bilges then I'd look at either the pressure regulator or the pump itself. When you run water in the sink or shower, does the pump start right away or after a small lag, and does it stop immediately when you close the tap? How old is your pressure regulator? Do you have a bicycle pump with a Schrader connector? If so, you could give your regulator a couple of pumps and see if it changes the problem.

[moonshadow]

Thanks for the advice. It seems that my accumulator tank is working as it’s supposed to. But a few pumps and checking the pressure is a helpful tip. I have a few bilge areas in my boat that don’t drain. No limber holes, so there could be water under the screwed in floorboards. I know that there are very likely some Tees in my boat plumbing that I haven’t ever found. I will have to keep digging for them.

[Mistroma]

It sounds as if you have tried all the obvious items.

I'm doubtful about the pressure switch as it would mean it is being triggered without a significant pressure drop. It is possible that it is responding to a tiny pressure drop but that still indicates a leak, though it could be very small.

Accumulator problems normally cause more rapid cycling. I usually pressurise mine once a season at most and it seems to hold pressure well. One tip I'd suggest is to get a metal valve cap and apply a small amount of silicone grease to the threads and seal. It means you don't have to worry about a slow leak at the valve.

If there's no sign of water then it might be a problem with valves inside the pump. It would cause the symptoms you describe. Water flows back from the pressurised side and the pressure drop triggers the pump. Might be a tiny piece of grit or more likely just a worn lip on a flap valve. It's worth dismantling the pump if all else fails. Parts might be difficult to source but cleaning and re-bedding might avoid purchase of a new pump.

[aussieodyssey]

Do you have a hot water service.Sometimes the over pressure valve can start weeping.

[moonshadow]

Thanks for all the tips and advice. I’ve been gradually working on resolving this. While I wish I had found a definite problem it seems that I have fixed it somehow.
I don’t think it was a water leak. The bilge pump cycling was simply a failed one way valve. So the same water was being pumped out of bilge and slowly returning.
I did go through every fresh water pipe connection I could find and pushed the connections as tight as reasonable. I checked the water heater and all outlet fittings.
I did also follow from the water tank to the fresh water pump and checked all the connections.
I pumped up the accumulator tank with air.
So? Now all seems well again. I wish I knew which was the problem but I’m glad the system seems to be working again.
Thank you again for the tips and advice.
Paul

[moonshadow]

Follow up. It turned out that I had two different problems. That was confusing. But after much frustration it turned out to be a simple fix. One loose connection between tank and water pump and a different loose connection at the dock water inlet fitting that bypasses my tanks etc.