Bilge full of water

[Bora]

Interesting day at anchor off Cala Bassa in Ibiza today!

Came below to hear the FW pump running....was running too long....checked all the taps were closed, no luck, opened up the bilge and it was full of water.

Great time for the RuleMate 1000 to nuts the bed as well!!  That’s definitely one to be replaced, the manual bilge pump did a sterling job though.

Traced it back to the pressure relief valve on the calorifier, I read in the manual that you should move it regularly to avoid calcium build up, I haven’t been doing this.

Drained the system and took it apart, no apparent build up of calcium etc, gave it a soak in vinegar anyway and reassembled everything.

FW pump would run for a while (filling up calorifier again) then the pressure would get too much and it would dump out the valve again.

Has anyone else had this problem?  I recently changed my FW pump to a newer Parmax 4 and there were no issues with water leaking out of the calorifer so perhaps the one way/relief valve can’t take the pressure any more and needs replaced?

For now I’ve reduced the pressure on the Parmax 4 and this has stopped any leaking from the relief valve and also the pump runs normally.

I’ll be turning off the FW pump from now on when I leave the boat unattended.

[Bora]

So....i've replaced the pressure relief valve at the bottom of the calorifier but the problem still remains.

If hot water is used from the tank and the FW pump comes on to replace the water in the tank it will sometimes bypass the tank completely and just come straight out the pressure release hose that leads to the bilge.

This only seems to happen when the onboard FW pump is used, not when connected to the dock water connection.  Does anyone know if the dock water connection has a pressure regulator in it?

I turned the pressure down on the pump again (having raised it following the valve replacement) and the problem seems to have stopped.

Could there be an issue with the calorifier that is creating excessive pressure and causing the relief valve to divert the filling water straight out?

On this topic....do most people's FW pumps run continuously when a tap is open?

[MickeyB]

I have an accumulator in my system.  The pump runs when the pressure in this drops too much, and then stops when the pressure builds up to some determined amount.

If my tap is NOT fully open, the pump tends to oscillate a tadge, always topping up the accumulator.  When showering with full tap open, the pump is always running full steam.

Sorry to hear about your troubles - the fact that not many are responding here probably means you have a very unique problem.

Mike

[MickeyB]

Actually - just re-reading your statement.  Could it be that you have a pinch or blockage in the pipe itself and that the relief value is actually doing what it is meant to?  Try blowing manually through the pipe with open tap and see what happens?

Do all taps cause this, or only the galley for example - could point to a local blockage?

A diagram of your water system may help us armchair engineers diagnose it for you.

I have installed a water maker recently, and changed all my plumbing so I have drinking water everywhere so I know my water system rather well, SO34.2.  Probably similar system to yours, just smaller :-)

[Bora]

For the pressure relief valve to be activating due to a blockage it would have to be in the calorifier however when i took the old valve off and fitted the new one the water flowed out of the calorifier no problem.

I think maybe the FW pump was just too strong (which would be strange as is a standard Parmax 4, replacement model for the original) and is set to cut in at 1.4 bar and then off at 2.8 bar.  The pressure release valve is supposed to activate at 6 bar.

Since adjusting the FW pump down a half turn on the pressure switch the problem seems to have stopped.....I just can't work out why it started in the first place.

I'll email Jeanneau and see if they can offer any insight but i won't hold my breath.


Now another topic....the noise of the pump! When there's no water flowing through it it's remarkably quiet...but as soon as the water goes through it's loud.  Has anyone soundproofed the area at all?  The pump has a thermal cut out so i'm not too worried about the space getting too hot.

[johannes]

Our pump is also very noisy. In our case I think it generates a resonance that causes the noise. I have been thinking about mounting it with some kind of rubber bushings but haven't yet come around to it.

[rene460]

Hi Findhorn, this sounds like a quite frustrating problem.  Certainly you are not alone, there are several threads on similar topics in the archives.

The issue really is dependent on only two components, the pump and the relief valve.  The normal pressure is set by the pressure settings of the pump.  The pump should shut off when it’s high pressure setting is reached.  There can be a little more pressure rise due to expansion as the temperature in the hot water system increases, or general ambient temperature increase.  An accumulator provides the volume necessary to accept the volume increase of the water with temperature with minimal extra pressure rise if you have one.

The relief valve set pressure should be something above the pump shut off setting, so in the normal course of things, the relief valve should never open.  Even with a blockage, the pump should just reach its shutoff setting and stop.  A blockage would mean that some or all of the taps might not flow, or might see reduced flow, but the pressure can’t rise above the pump shut off setting if there is any flow to any tap.

So if the relief valve lifts, we can assume that either the pump is not shutting off, and hence the relief valve is doing it’s job, or there is a fault with the relief valve, so that it is lifting prematurely.  Given that you have replaced your pump, I would expect that the relief valve is the more likely issue.  It is possible, particularly in systems without an accumulator, that the relief valve lifts a touch in response to the pressure increase caused by water heating, but instead of just relieving the necessary few drops, it does not reseat and continues to leak. This can be caused by corrosion of the valve seat, or by calcium deposits, if you have hard water.  In this case cleaning or manually lifting the relief valve to exercise it may help.

In systems with no accumulator, I assume that the diaphragm of the pump has enough flexibility to accomodate the necessary expansion due to water heating.  I have two systems without accumulator, one on my boat, and the other on a land based caravan.  Neither have given any trouble so far.  With my industry experience, my preference is first to leave well enough alone, but in case a problem develops, I will be adding an accumulator.  A new relief valve is not very expensive in either a chandler or an RV parts store.

When any tap is full open on my boat, the pump runs continually and the flow is set by the pump capacity.  If a tap is only opened a little, the pump generally can supply more flow than the tap is passing, the pressure increases, the pump shuts off so the pressure decreases and the pump starts again.  An accumulator slows the rate of cycling but it can still occur for a very small tap opening.  This is normal for this sort of pump, or any other positive displacement pump.

My boat does not have a shore based system, I just fill the tank with a hose, but the land based caravan does have a shore water connection.  The van system does include a pressure limiting valve in the land hose connection.  This works by shutting off on high pressure and only opening enough to allow the safe pressure when water flows, rather than by relieving.  It looks like a rather complex check valve.  It is necessary as land based water systems can have a wide range of pressure, so can easily be above the rating for your boat or RV system hot water tank.  My previous van had an adjustable one, worth paying for if you are ever replacing one.  But if everything is working, again I would leave well enough alone.

Oh, and the noise.  It should be silent when there is no water flowing as it should be off.  When it runs it is normally audible.  Ours is mounted on a square of plywood.  This possibly acts like a drum skin and even amplifies the noise, along with transferring the pump vibration to the hull.  We don’t find ours excessive, and it acts as our extra low water level alarm.  It normally shuts of almost instantly when a tap is turned off, but when the tank is near empty, it starts to suck air and cannot compress the air enough to reach the shut off pressure. The pump running on tells us the water level is too low, so we need to get back to our pen and get out the hose.  If you find yours excessively noisy, a thicker plywood base or some silkaflex or similar compound between the board and the hull may help.

I hope that helps shed some light on the problem.

rene460

[Bora]

Hi Rene,

I replaced the valve the other day thinking that it was a problem there, i then adjusted the pump back up to the original setting as supplied.  After running hot water for a minute or so (and then close the tap) the FW pump continues to run and the water flows out of the pressure relief valve.

One thing that did just come to mind.....when it goes in to this free flow state the little green indicator light isn't on.  Normally there's the red light to say the pump has power and the green light to show that the pump is running (as if the noise wasn't enough.)  So when the diversion to bilge happens i've noticed that that green light isn't on.

When i run the pump with the bleed cap upstream and a tap open to drain the system the pump goes really quiet when it's just pumping air, if only it would sound like that in normal op.

I'm going to look at lining the space with some sound damping foam and see how that improves things, i think i may just be spoilt with being on the shore connection a lot recently so i've grown accustomed to silent water flow.

[Bora]

Jun 27, 2019 11:03:56 GMT johannes said:

Our pump is also very noisy. In our case I think it generates a resonance that causes the noise. I have been thinking about mounting it with some kind of rubber bushings but haven't yet come around to it.

I've had mine running when i've been holding it in my hand (with water flow) and they're still really noisy, seems about the same as when bolted to the plate with the small rubber mounts supplied. 

[johannes]

The problem with the noise is mostly when someone gets up at night and pours some water, and wakes up everyone else. Maybe the only solution to that is better discipline and a pre-filled jug of water by the galley.

[Bora]

Especially if they're sleeping on the sofa bunk!

I'll let everyone know how the extra insulation goes.

[rene460]

Hi Findhorn,

It sounds like it is time to try and put a pressure gauge somewhere in the system and check those pressure settings, both the pump on and off and the relief valve setting.  The relief valve setting is usually selected to protect the hot water tank, and should be listed in your documentation or perhaps on a plate or tag.

Obviously the pump should shut off below the relief valve setting.  I would expect a good margins between them, perhaps 20% or more of the relief setting.  The low pressure setting or pump on can be quite low, it is not very critical, as usually the taps are open enough that the pump runs continually.

The mystery continues.

rene460

[Bora]

Back doing the anchor life so the boat is getting a proper run.

I found that the same problem is happening with the new relief valve as well.....it seems to be when the calorifier is low on hot water.  I put the generator on to heat the water and the problem has stopped again....for now.

I’ll test it again tomorrow, use all the hot water and then see when the calorifier is refilling whether it starts dumping in to the bilge again.

[so36idavid]

Regardless of the outcome of the calorifier investigation, I strongly recommend installing a bilge alarm. If there is a significant amount of water in your bilge you should know about it ASAP. Often people discover this when the floorboards start floating and sometimes that is too late to track down the leak. 

I have a second float switch mounted a couple of inches above the one that activates the pump. The second one activates an alarm. Float switches are notoriously flaky. This arrangement has the added benefit that in the event of a float switch failure I have a second one installed and ready to go. Snip a couple of wires and the bilge pump can be wired into the same circuit. 

[rene460]

Hi Findhorn,

Does your generator just power the electric element to heat the water?  I don’t know what temperature you are getting at the hot water outlets.  Once it turns off the power, the rumbling noise stops and the pressure should then be constant.  But while it is heating, expansion of the water has to be accommodated, if necessary by a few drops from the relief valve, but it should only be a few drops then it should reseat.  I am wondering if the thermostat is operating correctly, but it seems like a long shot.

It its about pressure, it is certainly a puzzle.  It would be quite unlucky to have a second pressure relief valve fail.  I think that pressure gauge I mentioned in a previous reply is becoming more necessary to help you track it down.  But let’s see what tomorrow brings.

By the way, I might be misreading your description, but the calorifier (hot water tank?) should be always full of water.  When you open a tap, the pump starts, cold water goes in at the bottom and displaces the hot water out the top.  This tends to increase the amount of hot water you can use before it is cooled too much by the incoming cold.  If you are somehow draining all the water, you need to fill it by opening a hot tap until you get water without entrained air before switching on the power to look after the heating element.

rene460

[Bora]

Hi Rene,

It seems to happen when the calorifier is out of hot water but water is still being taken. The FW pump just keeps running and then the relief valve empties into the bilge and the pump keeps running.

I have noticed some air in the system when I stop the FW pump and open the tap, the pressure is usually a bit higher than normal.

[cpetku]

Probably not related, but one thing to consider if the leak is intermittent is the temperature setting of the thermostat. If it's too high then the pressure relief valve may be activated. Had to adjust mine a few years back. However this was just an extra pump cycle every so often in my case.

[neworca1]

Hey Findhorn,
Sorry to be so late to this thread. I've experienced the exact same problem you describe and found that the cause was unreliable operation of the Jabsco pressure switch. After the original (to me) switch failed to shut off the pump--resulting in the tripping of the HW (calorifier) relief valve and subsequent running of the bilge pump you describe--I changed the pressure switch. The system behaved for a week, but then the same problem began happening again. I keep a cheap bicycle pump with built-in pressure gauge aboard--the kind with a little lever at the end that fastens the fill hose to the valve stem--so I hooked it up to the accumulator to see what was happening. Sure enough, when the Jabsco failed to shut off it was able to push the pressure well above 40 psi, tripping the relief valve. I installed our brand new backup Jabsco pump, but the problem--including the overpressure--continued. BUT, after fiddling with the little screw adjustment on the pressure switch, up and down, I finally found a setting where the pump would reliably shut off at about 30 psi. It's been good now for about 2 months, but we always shut off the pump whenever we leave the boat, just in case. And I completely agree about the noise level. If someone finds a solution I'd love to hear about it!

[Bora]

That’s great to hear you’ve found a solution! I’ve recently brought a small bike pump out with me to check the accumulator pressure but didn’t think to use it when the system is in operation.

I’ll have a tweak of it tomorrow and see where it’s cutting in/out.

Now also getting in to the habit of shutting off the FW pump when I’m not around.

Looking to put some foam insulation around the space the pump is in.

[rene460]

The bike pump with a pressure gauge is a great way to easily connect a pressure gauge to the system without disturbing anything to let you check the pressure.  

So long as you have an accumulator of course.

Remember that if you are adjusting or setting the air pressure, this should be done to the recommended pressure with the pump off and the water depressurised.

rene460

[Bora]

So it’s happening again 🤦🏻‍♂️

Just can’t win with this pressure relief valve lark, has anyone else had this and managed to solve it?

I’ve emailed Quick to see if they can offer any solutions, maybe a method of cleaning out the tank in case it’s being caused by small bits of build up escaping under pressure and jamming the valve open.

We’ve probably pumped about 50 litres overboard the last few days due to the calorifier always venting.

[sabmd42]

If I remember correctly, this problem started after you replaced the fresh water pump. The new pump may be faulty and set too high and therefore tripping the overpressure valve. I have heard this is a common problem with these pumps. Have you checked the pressure in the fresh water system?
Steve

[Bora]

I’ve got another new pump in but the problem has never really gone away. It doesn’t happen when I’m on my shore connection which is usually at a higher pressure than the FW pump onboard.
I don’t notice any difference in the accumulator pressure when I put the bike pump on there and cycle the system (no pun intended) it remains at the 3.5bar as marked on the cylinder.

[Charlie-Bravo]

I've been following this thread with interest, and am hatching some theories, having experience in plumbing, pressure vessels and water systems .... I'm intrigued.

Before coming to conclusions , could you repeat your test of running off the hot water yet again ( bucket sponges and pumps ready for the inevitable bilge full of water) but this time close the tap very very slowly, reducing it to a dribble before finally turning it fully closed.

Im not suggesting this as a remedy, but if you can make it not leak this way, it points to one of my theories hatching.

With this many brains on it, a solution can't be far away and will be good information for many in the future i'm sure.


One 'clue' you gave, it doesn't happen on the shore based set up but you feel that the shore supply has greater pressure, ..... are you sure about that? , or is it just a greater volume of water flowing from the tap, many of these pumps can give 50 psi pressure but running with the taps open only supply about 10 lpm, a 'mains supply' may not produce huge pressure but can give more lpm..... given pipe restrictions etc.

Good luck

CB

[shantiskipper]

Hey All, Sorry for showing up late to the party. I have been a member for a few years but have spent very little time participating. I plan to change that.

I originally purchased a new SO379 in 2015 and had no issues with the aforementioned water in the bilge issue. I like a dry bilge so this pleased me greatly. In 2018 I sold the 379 and bought a 2015 SO469 and soon discovered water in the bilge and eventually traced it to the pressure relief valve on the HW tank as well. I tried cycling the relief valve on a few different occasions, without a favorable result.
I then surmised perhaps a build up of minerals from hard water was the issue so I replaced the valve. Though it seems to have reduced the water in the bilge it did not stop it completely.
The hot water coming out of the tap is VERY hot, but so was it on the 379, so I don't believe that is adding to the problem. I entertained the idea of turning down the thermostat to see if that would help and to avoid scalding anyone but found that to be impossible without removing the tank. Being unwilling to tackle that task, I decided to wait for the day it's actually necessary to replace the tank.
Once in a great while my water pump will remain running after turning off the tap (with plenty of water in the tanks) so I just turn open the breaker, open the tap to let out a little pressure, close the tap and close the breaker again. This has always solved that problem.

On the 379 I always used a sediment filter on any water I put into the tanks since new, but on the 469 I did not have that luxury since I bought the boat used. However, since in my care, I have installed a double filter set-up (5 micron & .5 micron) for any water that enters the tanks. That eliminates any sediment and gives me a RO water quality product. Since the filters eliminate chlorine as well, I then add "Aqua Mega-Tabs" to keep the water from spoiling.

I know I've added no help in resolving your issue, but I wanted to let you know you're not the only one having this issue.
In my case the water i'm losing to the bilge is negligible, so I have given in to it, thinking again, when the day comes that I have to replace the tank I will address it then.
Also, I am not a live-aboard so when not on the boat I open the water heater breaker and of course the water pump breaker, which also greatly reduces water in the bilge.
Are other models having this issue or is it only specific to the 469?

On a related subject, when a tank does run dry and the pump continues to run, I again open the breaker to stop it, then switch tanks, open the breaker, and have found it necessary to cycle the tap on a few & off for a few seconds until water starts flowing normally again. Is this what others have found as SOP when running a tank dry?

Daniel