Pressurised Hot Water

CPD

CPD

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I'm about to buy a boat with pressurised cold water. I guess to add hot, I need a calorifier, pump and plumbing. Has anyone done this that wishes to share words of wisdom / advice / ideas ?
Many Thanks.
 
Yes I've done it. The ease of fitting depends somewhat on which engine you have. It is much easier with a freshwater cooled engine as there will almost certainly be blank plugs close to the freshwater pump as the output/input pipes to the calorifier. I can't comment on fitting to a raw-water cooled engine.

As far as the calorifier is concerned, ideally it should be fitted with the shortest pipe runs as possible to prevent heat loss but if you are installing it over the engine, make sure it does not impair access to the engine. When I bought my boat I had an engine problem that meant I had to completely remove the whole calorifier system to get at the engine. Needless to say, when I re-installed it, I relocated it in the cockpit locker so access was not a problem.

My system uses the same electric pump for both hot and cold water - the pump pressurises the system which is controlled by an expansion chamber and then works for both H & C. I installed a second expansion chamber after the calorifier in the hot water circuit but it was probably not strictly necessary.

We use Whale taps which have both H & C knobs but a common outlet. PM me if you want a diagram of the plumbing system. It is in the boat handbook (which is of course on the boat) but I am going there next week and could get a copy if it would help.

Hope this helps
 
Sorry I cant seem to get the width down!!!
Just look around for the calorifier that fits the available space. They come as horizontal cylinder, vertical cylinders, rectangular etc. Make sure it is firmly clamped into position as its pretty heavy when full. Use quick-fit plastic plumbing. Incorporate a drain arrangement for winter. The newer flow sensor pumps are excellent give good mixing and don't need an accumulator on the feed.If the system already has a pump you just split the output to give you cold water and a feed to the calorifier. The pressure into the calorifier then forces the hot water out.
Calcct1.gif

Make sure that you connect the inlet and the outlet the correct way round
 
Just replaced my califorier as the old one had passed its sell by and died a death last season.
I did the usual investigations in chandlers and found by far the best value, and as it turned out best service was surecal - www.surejust.co.uk an Isle of Wight firm - lots of sizes to chose from to suit your needs and space available and simple to install.
Ordered it by mid day Monday arrived by courier next day took about 3 hours to fit including the extraction of old unit and a few bruises !
Used push fit plumping, the sort with sealing inserts and two accumulators tanks (from penguin engineering) total cost including all fittings which included 4 flexible push fit hoses less than £350 and has allowed for the future fitting of a small radiator or two powered from the engine cooling system.
Surprisingly Halfords was the cheapest place for car radiator heater 5/8th hose !

Good luck
 
Our "new" to us auxiliary sailing boat has a Paloma gas-fired instant water heater that runs off the pressurised water. I believe that the Paloma heaters are no longer made, but I think there is another make available.

For a sailiing boat perhaps a colorifier may be less useful than a gas-fired water heater?
 
Don't forget that you'll use possibly a lot more water, especially if you've got women on board, and the tank should be at least 200L, preferably more.
 
I'm doing it at he moment. Only thing not yet mentioned, is if you have a long run from the engine, you may need to introduce another pump (agitator type) to push the water round the circuit.
Essentially, if you only have cold at the moment, you need H/C taps/mixers/shower; a method of heating (gas geysers are easier to install, and then just split the piping after the accumulator. Easily said... Best of luck.
 
Yes, we had one of them on our GK29. It was excellent for washing up and other such activities but I doubt if I could ever have got the flow to be regular enough for a shower.

It has been condemned at least twice in surveys on safety grounds, exhaust into the boat, but I don't really see how it's much different from a gas stove. There is no chimney or other restriction so it's difficult to see how any CO could be generated and it would never be left on for any length of time, as with a heating system.
 
Heres another system schematic.

It's important to fit a pressure relief valve to the HW cyclinder to vent if over pressure (select location of discharge carefully it could be very hot if a fault occurs) and if your fitting an electric immersion heater too, fit a high temp cut out thermostat in addition to the normal HW control thermostat (often in the same casing)!

BOATHWSYSTEM.jpg
 
I had a bosch gas water heater on my previous boat that would give SWMBO all the hot water she needed to run a galley sink 2 heads sinks and a shower.

On my new boat I have a simular heater but not bosch that will also run a clothes washing machine.

have a look here
 
Vyv, unless i'm much mistaken, and Alan has had a major change of heart and not told me, its a Volvo D1-30 with a freshwater cooling circuit...

Be interesting (and no doubt helpful to Alan) to find out what existing arrangements are on the engine for hot watre take offs for the calorifier if anyone knows...
 
Thanks very much chaps and I will you up on that, maybe after I have had a better look to see what is there at the moment and whether another pump may be needed.
 
Ay yes.
Yours is of course a Benny, but 40 foot with 2 heads.

Mine however is for a single heads. /forums/images/graemlins/grin.gif

and we have seen your fridge overflow plumbing mate.
 
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