In article .com,
Kev wrote:
My RCCD trip yesterday evening and I have narrowed it down to the down
stairs ring main but having unplugged everything it still trips. I have
also disconnected the central heating and kitchen fan at the spur box
but it still trips.
That only leaves the built in oven which I think is connected by a spur
so if it isn't that I am at a loss. I should be able to get to where
the spur for the oven breaks out from the ring but I don't see why this
should suddenly have gone as it wasn't in use at the time.
I can only assume that the next course of action is to progressively
disconnect sections of the ring between junction boxes to highlight
where the fault lies?
Is there anything else I should try before I call in a sparks?

How did you 'narrow' it down? Simply switching off an MCB doesn't disable
that circuit as far as an RCD is concerned - a neutral to earth fault will
still trip it. The only way to truly disable the circuit is to disconnect
line and neutral.

By far and away the likely cause is a faulty mineral insulated heating
element. To be found in immersions, washing machines etc and ovens.

--
*Stable Relationships Are For Horses.

Dave Plowman London SW
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