Having a Fisher-Paykel E442B refrigerator whose defrost heater element (part # 884509P) has failed for the third time in 3 years (just over warrantee this time), I have now realized the problem.
You see, when the system iced up (which I suppose any fridge eventually does) I had used a fan heater to defrost the cooler coil. What I didnt realize was that part of the heater element were 2 thermal cutoffs (like fuses) set to cut off permanently at 72 degrees celcius (see
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So in brief, in defrosting the frigdge I killed it (cost of repair AU$175).
Its odd though, the repair person uses a blowtorch to defrost the thing!
It would be nice if the manual said something about this. Anyway, I post this for the benefit of other fridge repair amateurs (and so that I can google it next time it happens).
Sandy