On Sun, 08 Dec 2013 10:32:39 +0000, Colin Stamp wrote:

I think I'll try getting the water to run down the side first. I think
what's making it worse is that it's already fallen the best part of a
metre inside the boiler drain pipe, so it's going quite fast when it
exits.

That doesn't help but sort of surprised that the condensate isn't on
the side of the boiler drain pipe as it leaves the boiler. If it
isn't I'd look for some means of making it so. Maybe a disc a
diameter slightly more than the ID of a joint with a segment removed.
Inserted into the joint so that the cone formed is pointing up,
anything falling down the pipe above should then hit the cone flow to
the edges and out through the gap made by the missing segment,
against the pipe wall.

--
Cheers
Dave.