Which RCD side for fan flue?

[Careful_Bodger]

I am having a new gas fire installed which uses an external fan flue. This fan unit is almost totally inset into the outer brick leaf. It requires a fused spur.

My question is should this be spurred off a nearby ring, and thus have the benefit of 30mA RCD protection (downstream from the 100mA delay type - its a TT supply), or could I spur off the central heating supply, which runs from the 100mA RCD side?

If the fan unit is switchy and glitchy, the latter would be best, n'est pas? Or is there an over-riding requirement where there is a greater degree of exposure to the elements.

The fitting instructions aren't clear on this particular question.

TIA,
CB

PS I am physically UK based.

 

[Qedelec]

Not conversant with fan flues but would expect the pupose to be, to take carbon monoxide away so probably best to take from C/H feed then the fan cannot fail without the heating going off, and suffocating all the occupants.

 

[Nige F]

As I read it . the fire is now`t to do with the Chauffage Central..Quel` que chose

 

[Adam_151]

Non-(30ma)rcd side, no reason it needs 30ma protection that I can see, protects it from failing in case of a faulty applience (which will trip the 30ma rcd), and if the supply does get cut to it, chances are, it'll be down to the 100ma time delay tripping, which will cut off power to everything, and is likely to be noticed