In article ,
Lobster writes:
Tim S wrote:

Why can't the drain go into an internal pipe, say a run that serves a
washing machine for example, that then terminates into an internal soil
stack?

No reason at all AFAIK. Mine terminates into a vented
washing-machine-type vertical pipe; although that then runs to an
outside gully.

Mine runs into the washbasin runaway.
One thing I did though was to fit an AAV u-trap on the basin,
so the run-away can't suck dry the condensate u-trap in the
boiler.

--
Andrew Gabriel
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