Thread: How to bend 40mm copper pipe 180° ?

@40mm have you considered other options aside from a in-fire wet back considering you have quite a small firebox? I would go with either a Yunca style water jacket heater that sits above the fire box or wrap 1/2 " copper around the flue as a heat scavenger but not welded to it. A tiny little pump can be used to push the water and circulate to a radiator. A friend who is a plumber has this set-up in his own house