On Sat, 21 Jun 2014 13:25:38 +0100, fred wrote:

In article , Bob Eager
writes
On Fri, 20 Jun 2014 18:32:51 +0100, BillP wrote:

Anyone have any ideas to join galvanised steel pipe to copper on a
central heating system (other than threading the pipe). Philmac UTC
15-21 does the join the data says it's only cold water rated

Over 30 years ago I had exactly the same problem. The local
(knowledgeable) plumbers' merchant sold me the solution, as as far as I
know it's still in there (we moved, but know the people who bought the
house as we only moved 50 yards).

A Johnson Coupling...

Interesting things but I'm struggling to find full information.

Are they really ok to use on heating? The closest data I can find is for
larger diameter stuff (Viking Johnson Megafit couplings - 2" min) and
while there is a nitrile based seal version for use to 100degC, it does
say, "Not suitable for fluctuating temperature, e.g. heating systems" on
that range.

I think ours was a nitrile seal (but it was a long time ago) so I may
just have been in blissful ignorance...

--
Use the BIG mirror service in the UK: http://www.mirrorservice.org
My posts (including this one) are my copyright and if @diy_forums on
Twitter wish to tweet them they can pay me £30 a post
*lightning surge protection* - a w_tom conductor