N. Thornton wrote:

Andy Wade wrote...

N. Thornton wrote:

I'm concerned by most of the advice in this thread - not just the
above. There coule be a live to earth fault and no bathroom bonding
for all we know.

How do you deduce that from the symptoms described?

what we can deduce is that that is one of the possible scenarios.

Sorry but it isn't. A fault (whether phase-earth or phase-neutral)
would blow the fuse quickly -- or if it didn't, due to gross
miscalculation of the circuit design, it would set fire to the cable
instead. Either way, the shower would be rendered inoperative.

OTOH the symptoms described here by the OP seem to me to be those of a
'slow cooking' of the fuse, probably over a lengthy period. This is
entirely consistent with a diagnosis of some combination of an
under-rated fuse and loose connection(s).

--
Andy