In article ,
cynic writes:
The rabid enthusiasm for installing condensing boilers seems to be
coming unstuck in our present winter conditions when the boilers heat
is most needed.

There seem to be a significant proportion of gas installers who,
although properly registered, actually haven't got the faintest
idea how a modern boiler works, and can't even follow the most
basic step-by-step installation instructions which all boilers
seem to come with (presumably because the manufacturers know a
lot of the installers are clueless).

No disrespect to the installers here, BTW.

The OP might want to sit down with the installation instructions
(which by law, the installer must have left with him), and just
check through how compliant the installation is, just based on
the things you can see without opening up anything.

--
Andrew Gabriel
[email address is not usable -- followup in the newsgroup]