Leaking calorifier

[robmatheson]

I need to bypass the calorifier on the boat. I can take the water pipes off easily enough and join them together - but what should I do with the two exhaust heat pipes? I'm assuming I don't leave them unvented. But should I seal each pipe? I don't want to get rid of them as I will have to attach them to the new calorifier (eventually). But, if I seal them, is there a risk the gas inside each one will expand and bust the pipes?

Thanks for any help.

 

[LittleShip]

I need to bypass the calorifier on the boat. I can take the water pipes off easily enough and join them together - but what should I do with the two exhaust heat pipes? I'm assuming I don't leave them unvented. But should I seal each pipe? I don't want to get rid of them as I will have to attach them to the new calorifier (eventually). But, if I seal them, is there a risk the gas inside each one will expand and bust the pipes?

Thanks for any help.

I think your going to need a picture, type of engine, reason for disconnecting your colorifier or some further info.

I cant work out what you are trying to do from your description above.

Tom

 

[RIN]

I need to bypass the calorifier on the boat. I can take the water pipes off easily enough and join them together - but what should I do with the two exhaust heat pipes? I'm assuming I don't leave them unvented. But should I seal each pipe? I don't want to get rid of them as I will have to attach them to the new calorifier (eventually). But, if I seal them, is there a risk the gas inside each one will expand and bust the pipes?

Thanks for any help.

Are you saying the exhaust from your engine goes through the calorifier? I'm no expert but I think this would be unusual. If mine is anything to go by, there is a pipe that takes hot water from the thermostat housing into the cal and one that delivers the colder water back to the engine. (A third being the Pressure relief valve that discharges into the bilge from the cal).
I would have thought replacing the pipes from and to the engine with blanking plugs or joining the pipes together would have been ok for a temp fix as long as they were secure.

 

[robmatheson]

Sorry about my poor description

When I say the calorifier's heated by heat drawn from the exhausts - that, of course, is rubbish. What I mean is I have two red rubber hoses from the engine COOLING SYSTEM which feed into the calorifier to provide heat for the water in the tank. There are two other black plastic in/out water hoses - on at the top of the calorifier, one at the bottom - and a final hose leading from the pressure release valve to a port hull vent.

I have to remove the calorifier because, for reasons I won't bore you with, I think some residual water has frozen - and possibly split the calorifier - during a serious cold spell. When the weather warmed up slightly I found some water slopping about immediately beneath the calorifier where there hadn't been before.

Basically I need to remove the calorifier, fill it with water and watch closely to see if it leaks. But this may take some time - and I want to be able to at least carry SOME water in the tanks to supply the sink etc - even if it's cold.

So I was wondering if I could disconnect - and blank - the pipe connecting the pressure release valve - then disconnect the black plastic water in/out pipes - and connect them together to retain the water supply 'circuit' as it were.

But I was also wondering what the effect would be of disconnecting the two red rubber pipes between the engine cooling system and the calorifier - and if I'd be able simply to blank each one off? Or would the pressure of the heated water from the cooling system be too great? Or is it necessary to connect THEM together to create a 'circuit'?

Sorry, I'm not describing this very well But I'd appreciate any help or advice.

Rob

 

[robmatheson]

Hallelujah!

Thanks bendyone - finally something that doesn't start with 'first remortgage your house.'

 

[bendyone]

Just connect the 2 red pipes from the engine together and then connect the 2 black pipes together so that you dont empty your fresh water into the bilge.

 

[DAKA]

When I say the calorifier's heated by heat drawn from the exhausts - that, of course, is rubbish. What I mean is I have two red rubber hoses from the engine COOLING SYSTEM which feed into the calorifier to provide heat for the water in the tank. There are two other black plastic in/out water hoses - on at the top of the calorifier, one at the bottom - and a final hose leading from the pressure release valve to a port hull vent.

I have to remove the calorifier because, for reasons I won't bore you with, I think some residual water has frozen - and possibly split the calorifier - during a serious cold spell. When the weather warmed up slightly I found some water slopping about immediately beneath the calorifier where there hadn't been before.

Basically I need to remove the calorifier, fill it with water and watch closely to see if it leaks. But this may take some time - and I want to be able to at least carry SOME water in the tanks to supply the sink etc - even if it's cold.

So I was wondering if I could disconnect - and blank - the pipe connecting the pressure release valve - then disconnect the black plastic water in/out pipes - and connect them together to retain the water supply 'circuit' as it were.

But I was also wondering what the effect would be of disconnecting the two red rubber pipes between the engine cooling system and the calorifier - and if I'd be able simply to blank each one off? Or would the pressure of the heated water from the cooling system be too great? Or is it necessary to connect THEM together to create a 'circuit'?

Sorry, I'm not describing this very well But I'd appreciate any help or advice.

Rob

Agreed with Bendyone, just connect the pipes to form two circuits.

Not sure that you are not going to a lot of trouble to find a leak.

Your tank will be made of copper that will allow a bit of expansion (frozen water), it will also be insulated and housed in a boat keeping the worst of the frost away.

On the other hand the plastic pipe fittings are more prone to frost damage and I have known these to crack.

I would dry everywhere, ensure the tank is cold (drips can be difficult to spot if they evaporate due to heat.)
and find where the water is leaking from, chances are you just need a new connection from B&Q and the tank can stay put.

 

[robmatheson]

hmmm

you might be right - and I hope you are.

I was going on the assumption that the water seemed to be lying beneath the calorifier and that's what made me think it might be that. I take your point about the frost-jacket etc. I'll have another look.

 

[T1ony]

ice

ice will normally find the weakest point,water can run from the top down inside tha jacket, you need to check the hoses, the hose connections and the spigets on the tank as they can tear, if its copper and not to bad you can solder splits but you have to be quick if its near the seems
Tony

 

[John100156]

Here's my two pennies worth:

Like others have said, I would not strip out the calorifier/cylinder just yet.

1) If the water is leaking from the secondary side (black hoses) then you will find the fresh water pump will likely cycle more frequently, which would indicate a leaky fitting or cylinder. The source of the water leak should though be obvious if the cylinder is accessible. If you by-pass the cylinder by connecting the black hoses together and the leak stops, it is likely your calorifier/cylinder that needs replacing.

2) If water is leaking from the primary side (red hoses) and its not coming from the fittings, the leak would be into the secondary fresh water side within the calorifier, it would not be external, it would contaminate the hot water and you would, I am sure, notice this. But it should not leak outside unless it is the cylinder/hose fitting. If the coil is leaking, when you by-pass the cylinder by connecting the red hoses, water should leak out from the pressurised secondary side through into the primary coil and will exit via the red hose connections which would now be open.

3) If it is intermittent, could it be a leak that only occurs when the pressure relief valve activates? Sometimes if the PRV discharge is piped out of a boat, the hose is dry until the PR valve activates. You should manually operate the PRV a few times to see if the drain hose connection is leaking. You will then need to investigate why the PRV is operating, HT stat etc.

Anyway, if you have any pictures it would help!

 

[RAI]

While you are taking the system apart, it would be a good idea to fit taps to the engine exit and return lines at the engine. Without them, a leak, or worse a burst, in you calorifier hoses could lead to your engine overheating badly. Even if you spotted it on the temperature gauge/alarm it is much easier to turn off the taps and top up with fresh water than first have to repair the leak/burst pipe before being able to run the engine again.

 

[dominic221]

I wouldnt be an expert in this, but I did have a similar problem. Where I would get a leak from the calorifier. I suspected that the tank was expanding when heating up and causing a pin hole to start leaking water. Spent an age taking all the fire extinguishers out to finally be able to remove the calorifier. Stripped it right down, wired it up to the mains. Only to find it was the pressure release valve that was faulty. It was hard to source a new one, based on the 1/2 inch thread and psi/temp rating. I did manage to get local plumber to source one though (and I brought two) and its been perfect since. My only suggestion to you would be if you have easy access to remove the relief valve and replace it, it will save you a heck of a lot of effort for the sake of a 30 Euro part. If it does turn out to be that. The ratings for the relief valve will be printed on it, so you can find an equivalent, just be careful with the length of the sensor probe, its ok to be short but too long and it wont fit into the tank.

 

[RIN]

I wouldnt be an expert in this, but I did have a similar problem. Where I would get a leak from the calorifier. I suspected that the tank was expanding when heating up and causing a pin hole to start leaking water. Spent an age taking all the fire extinguishers out to finally be able to remove the calorifier. Stripped it right down, wired it up to the mains. Only to find it was the pressure release valve that was faulty. It was hard to source a new one, based on the 1/2 inch thread and psi/temp rating. I did manage to get local plumber to source one though (and I brought two) and its been perfect since. My only suggestion to you would be if you have easy access to remove the relief valve and replace it, it will save you a heck of a lot of effort for the sake of a 30 Euro part. If it does turn out to be that. The ratings for the relief valve will be printed on it, so you can find an equivalent, just be careful with the length of the sensor probe, its ok to be short but too long and it wont fit into the tank.

I too had water in the bilge and eventually tracked it down to the PSV. Some bright forumite suggested that rather than replacing the PSV, I shoved the end of the hose into a platic 2L water bottle which I have done and no more water in the bilge. I empty it every month. The simplest ideas are the cheapest

 

[robmatheson]

Thank you all

These are all really excellent suggestions. I'm going to take a couple of days and track the problem down - if indeed there is one. Thanks again.