Hi, some friends would like a new combi condensation boiler fitted in the middle of the house & think I remembered on site a central heating guy was fitting a boiler that used 2 x 2” plastic waste pipes as a flu for the boiler. All they had to do was run slightly up hill , but could run quite a distance.
Any ideas on what make these boilers might have been. (It was a while back) .
Cheers.