Leaking Calorifier

[Dockhead]

Boat ownership means, more than anything: if it's not one d*mned thing, it's another.

I'm out for a bit of cruising and the calorifier is leaking. It is a vertical, 50 liter job which seems to have a copper vessel. There is a seam around the base of the domed top. A section of this seam -- a couple of inches long -- is leaking.

I would hate to have to replace this right now after all of the other big replacements I have done recently. I guess it's just a matter of time before the whole seam gives way, but I would be glad to get another year of service out of it.

So how best to patch this leak? I guess the seam must be brazed, but I can't do any brazing on this tank in situ. It would have to be remove, all the insulation removed, etc. -- a very big job maybe not worth it.

So how about epoxying a copper sheet over it?

Or how about that plastic weld stuff which is supposed to be so good?

Anyone have any advice?
Cheers, Dockhead

[skipmac]

If you can drain the tank and let it dry I think it would be worthwhile using one of the patching epoxies like Marine-Tex or JB Weld. I have always used Marine-Tex but hear good opinions on JB Weld also.

Once in an old car I ran over a rock that put a pretty good dent and a small hole in the gas tank. Didn't have a lot of money at the time so tried a DIY fix with Marine-Tex. Parked the car on a slope so the remaining gas ran to the back of the tank, crawled under the car and hit the spot a couple of times with a wire brush and slopped a little Marine-Tex on it. Very tight clearance so I could not reach it well enough to do a good job but never leaked a drop for the 2-3 years I kept the car.

Would try to get a fine bristle brass brush to clean the inside of the seam if you can and try to push some of the expoy into the seam with a gloved finger or Popsicle stick. Give it a day to dry and give it a go.

[joemac4sail]

Marine tex is an epoxy resin, check the specs to see how it copes with the heat of your calorifier.
Regards Joe

[Dockhead]

Thanks, guys. Couldn't find any JB Weld in Poole, but I did find something called "Sylglas Plumber Fix", which is advertised to work on burst hot water heaters, and is supposed to set even under water. It's a two component epoxy paste. I gave the leaky spot a good going over with a wire brush. Now I'm going to put some of this paste in the wound. We'll see what happens. Thanks again.

[skipmac]

Originally Posted by joemac4sail

Marine tex is an epoxy resin, check the specs to see how it copes with the heat of your calorifier.
Regards Joe

Not sure the max temp rating but I have talked to guys that used Marine-Tex as a temporary get home fix for cracks in head and intake manifolds. Hot water heater should not be a problem.

[skipmac]

Originally Posted by Dockhead

Thanks, guys. Couldn't find any JB Weld in Poole, but I did find something called "Sylglas Plumber Fix", which is advertised to work on burst hot water heaters, and is supposed to set even under water. It's a two component epoxy paste. I gave the leaky spot a good going over with a wire brush. Now I'm going to put some of this paste in the wound. We'll see what happens. Thanks again.

Good luck. Let us know how that works for you.

[Dockhead]

Well, the putty patch didn't work. The water comes right through tiny holes in the putty. I started to sand it down in order to put epoxy over that and just ran out of time.

And now it looks like I may have VIP guests (I mean really VIP) on board in a couple of weeks. I'm inclined not to mess with it any more and just replace it -- IF I can find one that will fit (vertical, kind of almost spherical, 50 liters, two separate coils).

Or maybe I should have it brazed by an expert?

The only thing is if the seam is already failing, then probably patching it will not be a long term cure -- or what do you guys think?

[Bash]

Originally Posted by Dockhead

The only thing is if the seam is already failing, then probably patching it will not be a long term cure -- or what do you guys think?

I think you're fighting a losing battle. Calorifiers have a limited life expectancy, and usually when something goes bad just about everything else is ready to follow.

Replacement is probably the best strategy.

[David M]

It's unlikely a patch is going to work along a metal seam given it is under pressure and there is thermal expansion and contraction.

[Dockhead]

OK, guys, thanks. That's kind of what I was thinking. I guess a new calorifier is in my immediate future

[joemac4sail]

Sorry to hear your first repair attempt did not work. A question to the forum here, about their thoughts on replacing a marine clorifier with a domestic model. As far as I can see, the only difference is that they use a stainless steel outer shell. But if the environment, where the tank will be placed is dry, the cost saving could be substantial. Plus, there is a greater range of models available to fit both the budget and what ever space there is available.
Regards Joe

[Dockhead]

Originally Posted by joemac4sail

Sorry to hear your first repair attempt did not work. A question to the forum here, about their thoughts on replacing a marine clorifier with a domestic model. As far as I can see, the only difference is that they use a stainless steel outer shell. But if the environment, where the tank will be placed is dry, the cost saving could be substantial. Plus, there is a greater range of models available to fit both the budget and what ever space there is available.
Regards Joe

Domestic hot water heaters are designed to keep water at about 60 degrees as far as I know. Marine calorifiers keep water at up to 90 degrees in order to make a smaller volume of hot water go further. Besides that, they have coils for your engine's gresh water circuit and, in my case, another coil for the boat's central heating circuit.

[joemac4sail]

I'm not sure about appliances in the states, but it's fairly s

[joemac4sail]

Sorry again on the bloody iPhone with agricultural hands. But a lot of the domestic systems have the same coils for hooking up to back boilers, set in fireplaces and stoves and the temp range is much more than an engine output. I'm going to check up the temp and do a bit of research in that area, thanks for the direction. Joe

[Pete7]

DH, the good news is the answer isn't a million miles from your current location:

Surejust | Manufacturing equipment for the marine industry for over 25 years

Pete