Have a look for Worcester 19/24CBI Problems (Over Heating, Fail to ingite)? as your problem sounds similar to mine. You could try warming your board with a hairdryer to see if it fires.
I changed my printed circuit board and now everything fires up correctly on timer. I reckon there is some sort of minimum temperature thermal cut out. Even if something is sticking in the mechanical department e.g. relays, dry joints or gas valves. Warming up with a bit of hot air may be a good test to try and isolate the problem or at least determine if it is your board. I found a site that mentioned that some capacitors 'dry out' over time and there performance changes/fails. That was a bit too teccy for me to try but sounded a reasonable argument. (Planned obsolescence and obligation to call service engineers! £££!)
My temp control issues are ongoing but at least things warm up when timed to!
Good luck and hope this is a positive step. Keep trawling this site as I am finding useful info everytime I search. There are some really helpful people out there.
Rob C.
January 2010
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