Boiler fires up when the heating and hot water are switched on but then cuts off.Then you hear a clicking sound which helps refire the boiler but may stay on for maybe 1-10 minuits,then the same proceedure again.It does work but cuts out(not consistant)and not sufficiant for heating and hot water needs.
Its hard to diagnose a fault with what info youv'e given. the clicking could be the ignition, I'd check the fan to make sure its working ok, be carefull all electrical connections are 240v
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