Fixed it myself.
It's probably the same fault as Goosepimpled had in March, but didn't create as much damage to the wiring as he/she had, and he/she is still waiting for an answer!
Check the temperature sensor on the outlet pipe, it's wired in series with one of the heater elements, so if it's become unstable , the power to that heater goes on and off.
The clue is in the melted plastic covers on the spade terminals.
It means that the device itself is generating so much heat due to the internal switch contacts arcing.
You have to buy the complete outlet pipe assembly (the sensor is not available seperately), but it does come with new wires and terminal block!!!
Incredible as it sounds , the part is actually much cheaper direct online from Triton spares dept than from other suppliers on the net. (83303160 £20.76)
I hope that helps someone else out there.
Tony Robson
May 2007
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