It started when the hot water cut in and out every now and then until it would not come on at all. We still had heating. I have had the heat exchanger off and cleaned inside. I have changed the diverter diaphragm but still to no avail and now i have lost my heating also. The only thing left to try is the thermistor but would this affect both the hot water and the central heating? Has any one got any other ideas please????

Andy Beales, June 2010