quite possibly someone has bypassed the rcd making it in operative the old style fuseboards would only be protecting power circuits therfore the other circuits not controlled by it would work. Another reason might be that none of the circuits are wired or protected by the rcd so whether it was on or off would not affect the circuits.
Tony
October 2008
The RCD is supplying something outside the house perhaps?
Peccavi
October 2008
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