Leaking Calorifier (Picture)

TwinRudders

TwinRudders

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Poole & Bath
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Hi,

My calorifer leaks through it's escape valve/drainage valve. I know the previous owner had the same problem and had tried changing the valve but it still drips and will fill a litre bottle in less than two days when the immersion is on.

Calorifier.JPG


The valve says 3bar - anyone know if it should be higher than this please?

Caorifier is:

CREWLINE 3KW 240v
Type CXC 311/13T

Thanks,
Jonny
 
3 bar is normal.Leakage is normal due to expansion.Mine has the vent piped with plastic pipe to the outside thro. the engine bay breathers. I cannot see a connection for a vent pipe on your photo. if not why not go to Plumb Centre and get one you can fit a breather pipe to. Is your thermostat set too high? as this can cause excess leakage. Should be about 130deg.
 
I've had the same issue with an Isotemp calorifier. After removing it and taking off the isolation jacket I found out the welding of the fitting that holds the valve was actually leaking. It was not properly welded and after 15 years of service the leaking became more and more apparent. I was lucky as I was able to have the thing repaired.

Cheers,

Arno
 
3kw seems a lot Jonny, I wonder if that has anything to do with the problem? It says in the bumph for my calorifier a weep is normal, though up to now mine does,t weep at all. it,s a 1yr old 'Isotherm' 16l 'slimline' with a 700watt immersion. As 'nedmin' says, look at the thermostat setting. Bill.
 
hello
i had the same problem and fitted an expansion (pressure) tank (i think i got it from force 4) i takes up the expansion when the water gets hot. works great and gives the water pump an easer time as well, it provided some header allowing the pump to run for several seconds and then stop for a period rather than clicking on and off as it did before.
 
I agree, 3 kW is a big immersion heater on a boat. UK electrical systems may drive it but many European marinas will not. 5 Amp breakers on many, thus a 700-800 Watt heater is fitted to most calorifiers. I can't see why this will cause your leakage, I can only say that mine doesn't leak a drop, 20 litres with a 750 Watt ( I think) immersion. My previous very old 25 litre calorifier, no heater, also never leaked at all. I don't have a hot water accumulator and originally didn't have a cold one either.
 
In France most houses have an electric immersion heater (same principle). The usual set-up has no expansion tank (as chez moi, where I have a 300 litres heater: the heating element incidentally is a mere 2.5 kW). These heaters are equipped with a gadget that feeds in cold water on demand, and incorporates a 6 bars (90 psi) pressure relief valve (which drips during heating). This valve is designed so you CANNOT put a hose on it: the safety regs impose a free fall for the expansion drip: this is to avoid calcium buildup on the PRV mechanism, which can lead to a permanent drip.... /forums/images/graemlins/mad.gifor an explosion /forums/images/graemlins/blush.gif. Your picture seems to show a pipe leading upwards (which would not be in the interests of the reliability of the PRV).
 
Yes indeed without an expansion tank it will leak as the water heats up and expands but I have to say they are notoriously unreliable things. This time of year when boats are re-commissioned after standing all winter there are always one or two posts like this. Often its frost damage I think. Mine went last year. Just replaced it and it's OK. Can't really get the little boogers apart to see what it is that fails but there is a key question. If you leave your feed pump on, does it "chirrup" regularly even if there is no hot water on? If so the thing is leaking. If it only leaks when heating water and you don't have an expansion tank fit one. If you DO have and expansion tank remember they need pumping up now and again. Perhaps it has lost pressure.
 
I would check that your expansion reservoir, a black 1 litre bottle, is empty of water. I think what may be happening is that there may be no air to be compressed in the system, therefore everytime the water heats up the water expands, and blows out.

3 bar should be enough, but your pressure pump will tell what pressure it is. These are very cheap to replace from a plumbers merchant (£3-5) so it may also be leaking steadiliy. You could go up tpo 3.5 quite safely.

To vent the expansion reservoir, take the pipe off the bottom, and open the valve on the top. Any water in it will drain out. Close the valve on tp and replace the pipe.
 
I very much doubt the Moody 31 has an expansion reservoir.

My 28 and 336 certainly didn't

Iota
 
An expansion vessel will fix the drip on warm up. What ever else you do, do not increase the presure of the PRV as this is there to protect the cylinder which, being copper will not be high presure. Local plumbers shop should be able to supply all parts and fitting to modify cylinder.
 
These PRV's are fitted to all <u>domestic</u> central heating sealed systems and we have been advised not to open them (for draining ) as often they wont seal again properly !
It is very common for these to drip on older systems requiring frequent topping up.
I would have thought there must be an expansion device fitted somewhere unless there is perminently a small amount of air trapped in the Calorifier for the expansion of water when heated or something would have to give or the PRV activate
pete
 
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