how can I fix my Micron 80FF Glow Worm Boiler?

I have also been having problems with my Glow Worm Micron 80FF boiler and non volatile lockout ever since it was installed. I have had a new fan fitted, the last one burnt out and still had a problem, service engineer told me my timer needed replacing, gave him money for a new one and have not seen him since. Bought a new timer on ebay, had it fitted but still have the same problem with non volatile lockout. Will make sure I never have another Glow Worm boiler when I see that so many people have had problems