rccb, test switch not working

[Kelrich]

alright everyone
my friend has asked me about his rccb, all he says is that the test button wont operate, it was wired up 30+years ago and the rccb is am told the main switch for the fusebox.
i am wondering is it possible for the test button to become jammed with lack of use over the years or simply worn out with age or something more serious, i havnt seen the fusebox so only know what ive wrote, would an rcd test tell me if it was worn out, also can it be replaced for a new one or would you recommend a new upgrade given that it was last done 30 odd years ago
cheers

 

[SPARTYKUS]

Test it first but if button broken it needs binning. Are you an electrician? If not I'd get one in to have a gander, lots of things to consider (like earthing system for example)

 

[trev]

I agree with Spartykus, you can test it but I reckon you have to be ready to bin it.