All sorted now.Managed by checking and testing one way or another to diagnose a faulty circuit board.Couldn't trace a replacement so contacted http://www.peterporter.co.uk/index.html
who reconditions circuit boards.He didn't have a replacement in stock but offered to fix mine and return it so I posted it off on Tuesday special delivery,he got it Wednesday morning and on Wednesday afternoon he called to say it was ready to return so I paid him about £40 including P&P and it arrived the next morning.Snapped it in and the boiler fired up.Fantastic service and really does deserve a mention again.
http://www.peterporter.co.uk/index.html
Michael.
October 2009