I need help from someone with an understanding of how Microwave oven's work.
The high voltage diode in my Microwave has burned out three times now. While the original diode lasted years, the first replacement went about six months (OEM part) the second replacement went another six months (direct from manufacturer). Now I am faced with replacing it a third time.
Everything else looks and tests out in there just fine according to the manufacturer's test grid and basic testing (like the capacitors appearing to have the right value, etc, switches all working). It does not die in a spectacular way, it just stops heating.
Obviously there's something else wrong here. Does anyone have knowledge of how these things work, and why the diode might be going bad repeatedly.
(In answer to the question "why not just buy a new one for $100" - this is a large built in stove hood/micro, matching the stove and the rest of the kitchen, in a color that can no longer be matched. It's probably 8-10 years old overall).
Thanks,