we are just about to put an unvented cylinder in, and i am having trouble working out where the discharge can go after the tundish, discharge will be in 22mm and go through a wall, under a bath and i want to put it into the 40mm waste from the bath. i thought i would put a t in the 40mm waste and a 22mm insert, surely this should be easy, but im looking online and cant seem to fins a 40mm/22mm insert, am i searching for the wrong thing.