Hi everyone,

I've got a "Steeple" split load consumer unit installed in 1997 with 2
* ring mains on the 30ma 80A RCD side. On the non-RCD side there are a
number of other circuits, including an outside socket, protected by a
"Powerbreaker" 30ma integral RCD socket.

We moved into the house in July. Ever since we moved in, we've been
having nuisance RCD trips, seemingly following no pattern. Everything
would be fine for a while, then all of a sudden the RCD would trip -
usually when using the shower, or maybe switching the kettle on.
Lately the problem seems to have been getting worse - it tripped
during the night, a period of low activity, apart from the immersion
heater which is on the non-RCD side anyway.

I thought it might be mouse activity biting through the cable, but
then...

....this morning I went to switch on the vacuum cleaner, a double
insulated device, i.e. no path to earth. Immediately the RCD tripped.
The happens on the upstairs and downstairs rings. As I couldn't see
how there could possible be an earth fault in the vacuum cleaner, I
plugged it into the outside socket protected by its own RCD but NOT
protected by the RCD in the consumer unit. It worked fine and did not
trip the outside socket's own RCD.

Am I right to suspect the RCD itself in the CU rather than any sort of
appliance or wiring fault? FYI the house was rewired in 1997 along
with the CU replacement - I've had a lot of floorboards up following
CH install and it all looks in good nick.

I am contemplating chancing £30.00 on a new RCD and wanted to get the
group's general opinion.

Thanks

Luke