the central heating control knob has snapped off and tje other part is still on the boiler, I was told the knob is designed to do this if the knob is turned the wrong way, to stop damaging the pcb. how do I replace with a new knob?

harry atkins, August 2011

its easy switch off power to combi take out PCB take out broken bit from PCB when taking out loop write down which wire goes where

lal, August 2011