hi all so I have an update, another engineer appointed by the council visited yesterday, I wasnt in when he arrived but he apperantly fixed the boiler Not sure exactly what he did but the radiators were still warm when i got in from work however another issue has arisen since he left.... the feed to the cold water tank seems to have an airlock in it, tank is empty and water is dripping into it, the mains supply is fine in the kitchen sink. Not sure how to fix an air lock in the feed to the attic tank. Google only has results when its the taps that have the airlock and not the feed to the tank. Anyone have any suggestions on what possibly could have happened and how to fix... i realise without knowing what he did its not much to go on