On 18/12/15 19:10, Tim Watts wrote:
(Spun off from Chris' thread).

Just noticed my water heater isolator (about 45A load) gets rather warm
after 15-30 mins of operation.

Tightened the terminals - but it seems to be the switch element - the
toggle base gets to perhaps 40-50C by feel. Never noticed before because
I'd never really gone around feeling shower/water isolators under high
sustained loads!

Personally I'd expect a simple switch to be stone cold even under
permanent full load.

Is this reasonable - or time to replace? It's a GET plate - only 6 years
old.

Cheers,

Tim

Well - I had a mate round (not a sparks) and I said: "touch that" (we
use highly scientific testing methodologies in this household!)

"Bloody hell, that's hot" he said.

At which point I wandered off to B&Q (being open late on a Saturday).

Interesting point - bought a Crabtree 50A unit to replace - the Crabtree
has twin screw terminals (except earths) +1.
It seems to have a ceramic switch unit mounted to a plastic body +another1
It says: "50A" on the back and the packet.

The MK one (identical to the current one) is in a box on the shelves
where the box and the packet say "50A" but it has "45A" printed on the
plastic. -10 for lying. The terminals are the same single screw type
mine is and the neon still has 2 weedly exposed wires that get pushed
around by the 10mm2 going into the terminals.

Conclusion: MK is not the brand it used to be.

I will attempt to disassemble the old one and see if there's any
interesting tell tales of overheating inside...