no oven for xmas :-( new 16amp oven on onto old 20amp breaker.???

[littlespark]

Why? You wouldn't normally RCD protect a fixed appliance in any other installation,

whether its normally done or not... i'm saying "I" would like it because i know how safe rcd's are compared to non RCD

And knowing how ovens are built, changed enough elements and fans to know, it wouldn't take much rough handling for the metal shell to touch a live contact inside.

 

[brianmoooore]

Haven't fitted an oven circuit, or any other domestic circuit without at least 100mA RCD protection since the early '80s.
Having said that, I see no requirement to retro fit a RCD to an existing cooker circuit, just because a new oven is being fitted, although I would point it out to the customer.

 

[Risteard]

I did not realise that ROI did not allow cooker switch/socket combinations.

As for RCD in general, do you not have the buried cable at < 50mm from surface rule we in the UK have?

No requirement for buried cables. Requirements for water-heating appliances and socket-outlets are traditionally much stricter though.