Terry Pinnell wrote:



Thanks for those prompt and helpful replies. I'm responding to the
requests for more info:

The unit is a 'Crabtree', and carries a label '8A/30mA'.


Is this the SB6000 series by any chance, or at least that series/vintage?
(20 years old or more I'd think now!) There should be a label somewhere on
the fascia.

If so, these are known to get 'twitchy' as they age, the breakers trip for
no apparent reason and the only cure is replacement. However, I'm not sure
the individual breakers are available now, you may have to replace the
whole distribution box if it becomes troublesome- like I did!

If the problem reoccurs regularly it would be wise to consult an electrician
and get a quote. If it's just the immersion heater circuit though, you may
choose to just live with the minor inconvenience if it isn't regularly used
and spare breakers can't be sourced- changing the whole distribution box
isn't cheap!

Morse