Leaking boiler

21 May 2003
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United Kingdom
Hi, just had a mini boiler disaster. The neighbours complained of a damp ceiling, and I discovered brown water was dripping from the boiler. Its a Potterton Suprema.

Of course I immediately turned it off and switched the mains off. I had a look inside and a pool of water has gathered at the bottom. There's not much I can really do obviously, not being qualified in these things, but does anyone have an idea what it's likely to be that's leaking? It's definitely coming from somewhere inside the boiler, there's no wet on top.

Thanks for opinions.
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Not an expert - not even a plumber (no offence to anyone intended!)

You have to find out where the water is coming from - sounds obvious I know, but it could be coming from a pressure relief valve, leaking joint etc. When you find out you'll then be able to work out the cause of the problem and sort it out. Come back and let us know.
Thanks Ian - yeah I posted the reply on a different topic as no one seemed to be reading this...

The leak is coming from the Heat Exchanger - it seems to be corroding on one side.

My plumber has recommend I use some Furnox (or similar) which he thinks may stop the leak in the short term - as a new exchanger is going to burn a hole in my pockets... :cry:

Do you think this may work?

How can I guarantee that I get the stuff into the system?
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You can put fernox leak sealer in and it might do it. But don't put other Fernox products in with this problem in your boiler as they might have the opposite effect !
What kind of boiler is it ? Reason I ask is if you have a central heating header tank you can put additives in there quite easily, but otherwise you end up putting it in the radiators etc.
The fernox will set you back 20 quid. Worth finding out how much the heat exchanger part is + fitting.
Its a Suprima 60.

Yeah I've got the stuff and about to attempt it.

The new heat exchanger is in excess of 200 for the part alone - ouch.
Well the leak sealer seems to have done the trick, the heat exchanger has stopped leaking.

How long do you think this fix will last for?

Is there anything I can treat the outside of the heat exchanger with that may stop it corroding further?
Glad to know it worked - I wouldn't have been super hopeful. Your rust is happening from the inside so nowt external matters. Your rads will be rusting too. How old's the boiler?

It may still have corrosive solder flux in the system. You daren't flush with chemicals but you could empty & refill a cuple of times then put corrosion inhibitor - and maybe some more sealer, in it.

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