Just thought it would be easier to handle. So it would be best to just use 35mm and 28mm? I guess the flow rate will be better with the larger diameter pipe.Why down to 22mm ?
Just one other question. The log burner also heats a hot water cylinder, there is no pressure/expansion vessel fitted on the HW . I'm sure it must need one as it is a sealed system. There is obviously an expansion vessel on the primary system other wise boom!