Whale Pump runs constantly with taps closed.

[Ian4624]

1994 Bailey Pageant CD Auvergne. Whale water system with hot water tank. Submersible external pump.
I'm returning to caravanning after a 20 year gap. We acquired the '94 Bailey last year. Our previous Musketeer had a very basic water system and didn't have hot water. I filled the water system a few times last year without any problems. So far as I am aware it is a pressure controlled system which I believe does not have any micro switches on taps.
I drained the water system for the winter as per the manual, including the hot water tank.
Brought 'van to house from storage yesterday to deep clean it. I filled the water system last night with a sterilising solution. (a powder which had to be dissolved in warm water) without any problems and left it overnight.
I drained that out this morning to flush through with clean water but the system will not fill. When the pump 12volt supply is switched on at the control panel the pump starts up sounding normal for a few seconds but then the sound changes and it runs continously but no air or water from the taps. Close taps and pump continues to run but water level in container does not reduce so I presume that it is not actually pumping any water. I did try opening the hot water tank drain again to see if anything was going into the tank but only about 500 mls of water came out. That would seem to indicate that it is pumping water for a moment upon start up then does not pump.
I've trawled around for info.and found two possibilities, or are they two versions of the same thing.
1) Remove the diaphragm from the pump connection in the caravan side, from outside but careful about the spring, or
2) Remove the pressure switch from the inside of the pump connection,
as they may be "gummed" up.
I suspect that some of the sterilising powder I used has not fully dissolved and is interfering with something.
Is the diaphragm at 1 above part of the pressure switch or are they two seperate entities and need to be dealt with seperately?

I've trawled for info and there seems to be

 

[ProfJohnL]

The symptom you describe is typical of an air lock in the pump pipe. If the pump has an air lock, the pump will run but will not lift any water. This prevents the pressure switch from operating.

To eliminate this, drop the pump into the newly filled container, and then disconnet it from the caravan to allow any air in the pipe and pump to be displaced by water, then reconnect it to the caravan.

 

[Ian4624]

Thanks Prof.
I had thought of that and considered disconnecting the supply pipe from the pump to ascertain if the pump was pushing water but in the light of your suggestion I decided to have another try this morning but instead of putting the pump in the normal water bottle I put it in a large open top bucket so that I could see what, if anything, was happening, or not happening.
I had allowed the van system to drain overnight.
I removed the front nearside seat cushion to expose the hot water tank and inside of the pump connection unit and opened the window above so that I could see and hear the pump whilst it was running.
The pump ran OK and the van system filled up as normal and the pump switched off correctly when the system was full.
However, as I was able to see the pump in the bucket I noticed that whilst the pump was running there appeared to be water ejecting from the hole on the top of the pump where the electric wiring emerges from it. Is it possible that there is an internal seal that has failed due to the age of the pump, or is this normal?
Anyway, as this appeared to be OK using the bucket, I drained the system down again catching the water in a bucket so that I could measure how much came out. 9 litres in the bucket, so the hot water tank had filled correctly.
I tried again with the bottle of sanitiser. Once again the original symptoms returned. Pump would not stop running.
I drained the system and measured the amount and again it was 9 litres, so the tank had filled up.
I tried again with the open bucket and all was well.
Tried again with the sanitiser and fault returned.
The sanitiser I used was a powder to be dissolved in water and I was aware that there were still small undissolved particles in suspension in the water in the bottle so I dumped that and rinsed and filled the bottle with plain water. Started the refill procedure again and all went according to plan and the system filled without any bother.
It would seem that the sanitiser particles in suspension were interfering with the pressure switch so next time I have to clean the system I will try to obtain a sanitiser which is supplied in liquid form.
Only problem now is that the pressure switch is cycling off and on (more when the tap control is less than fully open). This is more easily heard as I have the seat cushion removed. Before I start trying to adjust the pressure switch, could this be caused by the pump not delivering at full rate due to the aforementioned apparent ejection of water from the electric cable entry on the top of the pump ?

 

[ProfJohnL]

You should not be getting water emerging from the wire port on the pump. That is definately bad news, and you will need to replace the pump.
If teh sanitizer has undisolved particles, then it is certainly possible that some of teh particles could be interfering with the pressure switch. Most likely it will prevent the non return valve (Built into the presure switch) to close off properly allowing fluid to drain back down the inlet pipe. Following up the sanitizer with fresh water seems to be flushing the particles, so the pressure switch may be unharmed.
However if the system keeps pulsing on and off when all the taps are shut, then that is a classic symptom of a leak, and it coudl be the NRV in the pressure switch not fully closing.

 

[Ian4624]

Thanks again Prof.
I thought it strange that water should be eminating from the wire port. That would appear to indicate that a proportion of the water drawn into the pump is not going up the intake pipe to the van. I guess I'll have to replace the pump before it fails completely and it may be wise not to adjust the pressure switch until I have done so.
I may not have made myself clear about the pressure switch cycling. It does not do it when the taps are switched off. It only occurs when a tap (any tap) is opened and the frequency reduces as the tap is opened more fully, but it does not stop completely when the tap is fully open.

 

[colin-yorkshire1]

hi Ian,
It seems to me that you have made a couple of errors that have culminated in your present situation, but not to worry it is easily sorted,
making errors is something that we have all done from time to time as caravanning is a learning curve, you learn something new remember it and move on!.
I believe your problem started with the wrong type of seriliser (powder) use a liquid one like milton "I use wilkos own brand" and it was left in the system too long! (overnight) 15/20mins should be sufficient for it to do it's job, it seems likely the fluid has damaged the pump and gummed up the pressure switch, allthough to be honest it is possible the pump is a bit worn, and you have not noticed afterall it is not usual to have the pump in a bucket of water and look at it running through a window?.
either way as the Prof said water should not be comming out of the wire gland, and it should be replaced, as for the pressure switch! I dont think this will be damaged and should be fine once a few aquarolls of water has been through it, but it will need adjusting once setup, I do this a couple of times a year as the adjustments are so fine just a little off adjustment makes a big difference to the system effeciency and pump timings.
I would suggest that you replace the pump and then once filled run 5 or 6 aquarolls of cleanwater though the system to flush out any remaining crystals, re adjust the pressure switch, and drain down completly, if your van has a water filter this should also be changed as the seriliser contaminates them and destroys the charcoal, even if the filter is just the plain sponge type it can leave a after taste in the water that lasts a long time.
next year when when doing the water, fill the aquaroll with warm water add the right ammout of liquid fluid and mix well then fill the system as normal hot and cold taps open, and connect the waste hog to the drain, once full leave for 20mins max and run the water through the system into the waste hog, untill that is full and then disconnect it, (leaving this a few hours should serilise it also)..
once the hog has been disconnected run a further 5 or 6 aquarolls of clean water through the system to rinse it out and then turn off the taps, readjust the pressure switch, and drain down completely, replace the filter "if you have one" and leave dry. and thats it job done,
one other tip, when leaving site drain down the system into the empty wastehog add a portion of bleach and mix well leave this in untill the last minute and dispose of it down the Elsan point this will keep the wastehog fresh.
last point, refering to "I may not
have made myself clear about the pressure switch cycling. It does not do
it when the taps are switched off. It only occurs when a tap (any
tap) is opened and the frequency reduces as the tap is opened more
fully, but it does not stop completely when the tap is fully open."
this is symptomatic of a badly adjusted switch or it may be just gummed up once the pump has been replaced and the system well flushed out the problem may well disappear but a final adjustment may be required,
hope this helps.
Colin

 

[Ian4624]

Thanks for all the info. Colin. Sorry I haven't been on the forum for a while as I've been busy.
Whilst deep cleaning and fixing various minor issues on the van I've run another two 5 gallon containers of clean water through the water system and it has settled down nicely. Switching off when it should and no cycling off/on. I haven't replaced the pump yet but it is on the list to be dealt with asap.
I've noticed at the caravan centres that the complete pump/tubes/plug assembly are available as a unit and that the pumps are also available seperately with wiring to connect to the plug unit. Has anyone wired in a replacement pump, and if so, was it a success? I'm tempted just to buy the complete unit.

 

[colin-yorkshire1]

hi Ian, it really depends on on how you feel about stripping down the old pump, and the capacity of the replacement, buying a full set (complete unit pump, pipe and plug) is quite expensive but of course simpler, make sure you get the right plug end though as there are several types, these will be a direct replacement for the original.
however if you require either a cheaper option or a higher capacity pump, you will have to strip the old one down, this is quite simple if you attack it from the plug end, undo the 2 screws, pull off the outer cover (that goes over the pipes) and slide it down the pipe, this leave's the inner bit, you will see where the pipe and wires connect, disconnect them and pull off the plug,(noting which way round the wires were connected) one should have a black trace "this is the earth or neutral" at the other end of the pipe the pump may have a jubilee clip undo this and pull off the pump it should now come away from the pipe with the wire attached you should now have 3 bits the bare pump with wire attached a piece of double tube and a plug,
shove the wire of the new pump up the pipe untill it appears at the other end and fit the pump onto the tube and tighten the jubilee clip at the plug end affix the wires (as noted before) trimming if required, and fit the water pipe to the plug, pullup the outer sleeve and affix the screws, job done, connect it up to the van and test in bucket of water.
it is really easy to do, and can be done in 15 mins, of course you could do both buy a new one and refubish the old one keeping it as a spare,

 

[Ian4624]

Thanks Colin,
Re your first post, my water system does not have a filter so that is not an issue. When I had my old Musketeer, the one I sterilised with the powder, I used to drain the steriliser into the waste bottles to give them a bit of a clean. I always intended to replace the corrogated flexi waste pipes with smooth ones but never actually got around to it. There must be some awful gunge inside those flexi pipes. One thinks of that intestinal disease "diverticulitis" which affects some of us.
Thanks for the info re replacing the pump. I did think that it seemed to be a very straightforward screwdriver job and I have no concerns about my ability to do that but I've been caught that way before. That is, replacing one component to keep the cost down then finding that a short while later the other part has failed and is not available separately so I've had to but a whole new unit anyway. I do understand that if I buy a complete unit I need the correct plug end. It seems from your "how to" that you have done this successfully yourself so I may just go down that road.

 

[colin-yorkshire1]

hi Ian, yes many times over the years I always carry a spare one just in case, my present spare came off the m/home but the plug was different so I changed it, £5 off Ebay. it is worth just changing the pump though, because if you think about it there is nothing else in the unit that can go wrong.

 

[Ian4624]

Thanks again Colin. I think that I will just replace the the pump as soon as I can get around to it. I'm busy sorting out a few other problems at the moment. It seems that the more I fix the more I find that needs fixing. Nothing major, yet, just fair wear and tear due to the age of he van. It's 1994 vintage.