I have recently moved house and on looking into the central heating system note that it is an old 'C' plan set up with gravity fed hot water and pumped CH. The controller is quite modern and can control HW and CH independantly. There is a cylinder stat and 2 way valve controlling the HW temperature and a room stat controlling the CH. My concern is that when the HW temp is satified (the valve shut) and the room temp is satified (CH pump off) the boiler is still on (although controlled by its own thermostat). Is this a normal set up or is there a wiring fault? Should the boiler not shutdown if both HW and CH are satisfied?