Customer is having problems with hot water temp ,the hot tap has got to be turned down really slow to 4 litres a min to get hot water temp up to 40 degs I ve got 12 mbar burner pressure the temp of the primary flow is 52 degs. I ve checked that the potentiometer is turned up ,both dhw and ch thermistors reading 4.4 kohms and 5.2 respectively there is no heat going down the flow or the return pipes ,the boiler runs constantly I am thinking its the pcb not controlling the sensors correctly anyone any ideas cheers
