In article ,
"Set Square" writes:
In an earlier contribution to this discussion,
Andrew Gabriel wrote:

. Might want to
keep the length of run to the 110mm soil stack as short as possible,
particulary the outdoor part of it. Condensate is still slightly
warm on mine when it runs into the pipe, so it would probably be
quite difficult to get it to freeze inside the loft area.

I think it's an *internal* soil stack - so there wouldn't be an outdoor
part.

Oh yes, missed that bit.

Presumably the condensate isn't hot enough to damage the plastic soil stack?

Well, you would expect to be able to pour boiling water down a
soil stack without damaging it, and the condensate doesn't get
that hot. Actually, it probably can't exceed 55C in theory,
although some boiler designs might conceivably be able to heat
it up slightly as an unintended side effect after it's been
condensed out by passing the slightly hotter flue gases over it.
(In the Keston, the flue gas is only 5C hotter than the boiler's
flow temperature, so this is a negligable effect, if you manage
to see it at all.)

--
Andrew Gabriel