Roger Mills wrote:

Thanks for everyones replies.

I've owned 2 Baxi Bermudas in the past - both 1960's vintage - so I don't
whether yours is the same.

I think mine is a bit newer - probably early 80s.

Mine had cast iron heat exchangers which looked a bit like 2 chunky slabs of
chocolate - with the chunks facing each other. Each of these had 4 holes in
the corners, and were joined together by 4 manifolds - each of which had an
external connection - i.e. 2 flow + 2 return in all.

That's exactly the same as ours.

I think there were gaskets of some sort where the manifolds joined these
"chocolate blocks". If yours are leaking, it is probably at these joints,
rather than as a result of any holes right through the cast iron.

Sounds reasonable. I can't see the cast iron itself failing unless it's
split or somehow become porous.

If you can get them apart, you may be able to replace the gaskets. However,
the bolts holding it all together are probably well and truly rusted in - so
it may be difficult. You can probably still get a replacement burner
assembly from a Baxi spares stockist.

I've checked and the replacement parts are available. Looking like ~120
quid for the various bits.

The reason I want to try and repair it is :-
A) I can't really afford 1400+ on a replacement
B) We're probably moving house within the next 12 months

What's the efficiency of a back boiler compared to a modern unit? I
really can't complain at our heating bills up to now (and they're
v.cheap at the moment!) - unless it halved the bill I can't see
replacing it is a great benefit for us.

Are grants available for replacing back boilers with a more efficient model?

Cheers,

Steve.