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Water deck filler

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I'm in the process of replacing both our cold water tanks as the old ones had various leaks and once they were installed, I had no success at all in reconnecting the main deck filler hose to the main inlet.

The tanks are Aquaflow models and have an inlet which is quoted as one and a quarter to one and a half inches OD whereas the deck filler OD is nearer two inches. The current hose is the green armoured sanihose which is pretty hard if not impossible to flex and that's why I can't bend it enough to reconnect the filler.

Ideally, I need some hose which is smaller (and more flexible) in diameter and then use a coupler to connect it to the existing hose which would need to accept 2 inch internal diameter on one side and one and a half on the other.

Any suggestions would be much appreciated cheers

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Have you had a look around your local caravan dealers accessory shop? :)

They often sell several diameters of waterpipe including the flexible types for use around inboard water tanks on Motorhomes, plus the very bendy stuff for draining away the wastes on shower trays and grey water points in caravans. cheers

Worth a try is a place called O'Leary Caravan Supplies, I havent used them for a couple of years now, but hopefully they will still be around, and they are also good for all the types of switches and light fittings, laminates and clips ect that maybe difficult to find anywhere else, their speciality is DIY supplies to the home convertion enthusiasts, who buy a Van and convert it to a Motorhome, or those who are building their own narrowboat from a purchased hull :)

I will try and find the link off my old computer and post it up, they also do a forum with 'How to do it' advice with pics :dance


Julz :wave

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I can't see either the hose or a reducing bush being a problem to source locally Jim as Perry has posted ASAP are a good source but I reckon you'll find what you need in any good chandler or as Jules says caravan accessory place.

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Thanks everyone!

Fraid I tried the heat method and the hose stays as rigid as ever! I think I will either change the deck filler and hose or split the hose into two different sizes using a stepped coupler.

ASAP are very good indeed so I may give them a try for all the bits. The main problem was that some of the wooden panelling was built around the tank originally, so it's a lot harder to work on with everything in place. If I remove the panels, it will do a load of damage and create even more work :o

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Following a bit of brute force, use of a sharp stanley knife and loads of effort, the old hose was finally removed. Reducing bushes seem to be \a bit hard to come by both at ASAP and Norfolk Marine, so I have to modify my idea and join two different hose types together which I'm sure will be okay.

The next problem is the hot water system but before I go into detail, it's probably best to explain how the existing water system operates. Basically, the boat was fitted out with two cold tanks, one in the bow which holds 10 gallons and a second located low down in the bilge under the thwartships cabin which holds 7.5 gallons. Next to this sits the 9 gallon copper hot water cylinder and the system is operated by an electric pressure pump which pressurises the 7.5 gallon cold tank. The pump is operated by microswitches in the taps and only operates when a tap is opened.

I quite fancy the idea of fitting a Hotpot cylinder in place of the existing unit because the water takes ages to heat up. There is no circulation problem but the existing cylinder has a very poor heat transfer coil and the water from the engine passes through it too quickly. In normal circumstances, the feeder hose should be hot and the return cooler but in my case I find they are both the same temperature and as a result, the heat exchange process is poor. The advantage of fitting the new Hotpot is the fact that they are much more efficient in the heat exchange process and also they come fitted with a mains powered immersion heater. The latest version also has an automatic mixing valve which takes the hot water temp down by mixing it with cold water before it comes out of the tap. Here's the possible problem..........

Even the smallest Hotpot wont fit into the existing tank space and there is no place else to fit it except in the engine bay which would mean mounting it higher than the existing tank. Does anyone reckon there will be enough pressure to fill the hot tank up when it is higher than the cold feed?? ..or will it not fill up at all?

It seems the existing system was using gravity plus the head of water from the bow tank to push things along so to speak and if I mount the new tank in the engine bay, it will still be lower than the bow tank but higher than the second cold tank.

Once again, any similar experiences would be appreciated :teddy:

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Assuming the pump is before the hot water tank I can’t see an issue Jim provided the pump will give enough head, which most domestic pumps will with ease. The hot tank on our boat is in the engine compartment and above the water tank (builder designed and fitted) and performs perfectly well One point to bear in mind is if the Hotpoint is a domestic one then the element may be a bit higher current draw than normally fitted on boats. Also if your boat is raw water cooled, these run a lot cooler than a closed system and the performance of a calorifier (heat exchanger) will always be lower than a closed cooling system.

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Thanks David!

The Hotpot brand of calorifiers are built for the marine market so the current draw should be okay. The BMW 220 engine has both an internal and raw water cooling system and the calorifier runs on the internal circuit just like a cars setup. The water feed to the coil from the top hose outlet is at about 80 degrees C and ASAP claim that the Hotpots will be full of hot water in 30 mins, such is the efficiency of their heat exchange coil.

If I do fit it in the engine bay, it does mean we can have a bigger tank than present and the only prob is deciding where to mount it :?

The current hot tank has a "radiator cap" style pressure relief unit and when I tried to run our system pressurised as opposed to the tap switched system the pump blew water out of the relief valve and even after fitting the highest pressure cap I could get.....water still came out so I think the pump can handle it okay!

I would love a pressurised system but to do that, I would have to fit new galley taps and I just cant find any that are small enough. The problem with the existing ones is if you did operate on pressure alone, they would leak as the connections are push fit and not as secure as a solid threaded seal. They don't leak under normal operation so we are stuck with them!!

If there are any more leaks after I have finished this latest upgrade, I swear I'm gonna jump off Wayford Bridge two guns

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So far so good and we seem to be leak free at last :teddy:

I'm still investigating the calorifier options as the Hotpot range of sizes won't fit in the space where the old tank sits. If I had a pressurised water system, fitting the tank in the engine bay would be fine but on checking, it would seem that the hot tank would be higher than the middle cold tank if I do fit it in the bay and as a result, I doubt it will fill up with cold water properly because it won't run uphill.

As far as I can see, I might have to get a calorifier specially built which will fit in the existing slot.

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Thanks Jim I'll give it a whirl!

I've just sent an email to ASAP in Beccles to see what their teccie guy thinks would be the best option. Ideally, I would prefer a pressurised water system but unless I can get hold of some very small galley taps, it would be a no go. Basically, the existing mixer tap is no longer made and the fittings simply push into the base of the unit and are sealed by a rubber olive. When I removed the hot tank 2 years back, I coupled the feed and return hoses together and the pump operated automatically until the desired pressure was reached and then switched off. The only problem was those taps and when I opened the galley doors, a waterfall hit me where those olives had leaked!!

All the diagrams I have seen show the water pump as an in line unit rather than the type we have which simply draws in air one side and simply pressurises the cold tank causing water to come out when the taps are opened. In a sense it runs just like a compressor. As far as I can see, if I had the inline type of pump, siting a larger calorifier in the engine bay would not be a prob as the pump would push water into it, even though it would be above the level of the middle cold tank.

I will get the problem of Topaz and her waterworks sorted for sure. It's only taken 5 years so far two guns

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ASAP have come back to me and confirmed that a calorifier that will fit into the existing position would have to be a special build as all the existing units are too big :cry

Not only that, they also agree that siting a new calorifier in the engine bay (where there is room) would not be a good idea as it wouldn't fill up properly and would be reliant on the bow water tank remaining full which would produce enough head to fill it. Their suggestion was to replace the existing pump with an in line unit between the second cold tank and cold inlet to the calorifier which could still be switch operated and that way it would keep the tank full.

I did find some very good diagrams on marine water systems yesterday so I'll try and post up some links for all to see. cheers

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