I have a 1 year-old honeywell central heating programmer which has never worked properly - it seems to lose power for no obvious reason and then the boiler decides to go out in sympathy. Question: is it difficult to replace the programmer (ie. is there a backplate so I can simply remove the programmer and plug in a new one?
I would say it depends on the boiler, but I had one about 10 years old that got iffy and an engineer replaced that with no problem. As it is a gas appliance, you should, by rights, get a CORGI engineer to do it, even tho you aren't actually touching the gas part.
If the programmer is still veing manufactured It would be possible to swap it over if yours is designed that way. If not, not too hard to change it - you dont need a Corgi fitter to do it but would be advised to get an electrician if you dont know what you're doing.