I had a similar problem with Triton T50.
After a period of time, water creeps into the back of the unit and in my casehad got into a small micro-switch.
This caused arcing/shorting out and eventually failure of the unit.
Do not know if the bits are available separately but my unit was also caked full of limescale in the heater (We live in a hard water area), so I fitted a new unit
Hope this has been usefull to you and good luck!!
Regards
Andy
Andy Clarke, August 2008