Thank you BD, it would now appear that the clock is unreliable in that it now works (but for how long?) the digital version you mention, where would I get hold of one (approx. price) and who are the makers.
George
Our boiler normally behaves as it should but last night my wife switched the boiler to automatic as we normally do but for some reason it will not go to automatic but remains on even although the switch is in automatic mode
We now have a boiler that we can switch on or off and works ok but...