My 600cth just won't switch on, no lights nothing as if there is no power to it. i've looked at my mains switchboard; the fuses all seem ok. Has anyone experienced this fault previously. It was installed 2005, and has had the pcb upgrade to get rid of the flashing 56 problem, since when it has worked perfectly.

I'd appreciate nay suggestions as to what the problem might be.

Keith Corless, July 2015