On Wed, 28 Mar 2007 11:19:20 -0700, Daljit wrote:

1. would there be any problem with reducing the condesate outlet pipe
from 22 mm to 15mm a couple of feet from the boiler, running it under
floorboards for approx 30 ft and then feeding into 40 mm kitchen waste
pipe? (trap in boiler)

If you're having it do a U shaped run I suggest you make it an open
standpipe at the boiler end so the condensate waste always has somewhere
to go. Otherwise you may find it airlocking and backing up into the
boiler which doesn't work too well with water sloshing about in the
combustion chamber :-)



2. how would i connect the 15mm pipe to the 40mm one?

You must have all the pipe be in plastic (can you really not run 22mm
plastic all the way?). You can go 22mm into a rubber adapter (from
screwfix, toolstation and/or BES, I forget which) into 40mm or you can
reduce 40mm to solvent-weld overflow (nominal 21.5mm OD) with various
standard adapters and join to that with a 22mm push-fit fitting.