Combi condensate pipe to rainwater downpipe.

Glass fibre reinforced resin was used to build Co-Rist chemical pumps handling concentrated hydrochloric and other acids so you ought not to have problems on that score.

It's supposed to go directly into a drain. Mine goes out over an extension roof, and it's clipped to the wall and deposits it's acidic crap into a gutter, directly above a down pipe, I could have had it running on the roof, but it tends to splash and christ only knows what mess it would make of the brickwork, not to mention the tiles.

Isn't there a possibility you could route it inside the house closer to the stack, then there's only a short piece showing outside?

An alternative, albeit somewhat more expensive, is to use a condensate pump near the boiler which then uses flexible polytube and can pump uphill to a more convenient location.

My boiler is in a first floor airing cupboard, and the condensate pump outlet then goes up through the ceiling, across the joists and then to a soil pipe. Has been working fine for two years now, and the pump is very quiet and unobtrusive.

it's not acidic enough to worry about ... a tomato is probably worse !

That would have been my best option had the floor not been tiled recently - bad planning I know. I am considering chasing the wall out behind the skirting and seeing if I can run it behind there. Thanks for the advice.