My plumber mate who is helping me fit my ASHP reckons I need two traps for one pipe and I am not so sure. I have the relief valve for the cold and the blow off for the UVC going into a waste pipe. My mate reckons there should be a water less trap directly underneath the tundish, the 1 1/2 pipe then runs round to the 110mm pipe but I need to put in the drain for the steam oven so he said just put in another trap and connect the oven.
My question is why cannot I not just have one trap directly of the 110mm stub pipe and then attach both the steam oven and UVC at their respective points? TIA