I have a Frigidaire FGMV176NTB range hood microwave oven which was installed new about two years ago. It works fine, but recently started tripping the 15A standard breaker it's on (Siemens c. 1992) when we occasionally open the door to end cooking. This occurs every time or nearly so.
The only other loads on the circuit are a few LED lights. It operates normally in all other use cases, including when the timer ends cooking or the Cancel button is used.
Further test results...
- The door is aligned with the frame as it was when new. I ran a test by lifting slightly and opening the door, and the breaker tripped immediately. Door sag/alignment does not seem to be my problem.
- Power was connected to another kitchen circuit. A slight pull on the door handle tripped the GFCI outlet. The breaker also tripped on a third circuit without GFCI protection. A faulty breaker does not seem to be my problem.
Update again: And now the unit is completely dead. I'm ordering door switches and a primary fuse and will report back.
And again: I've replaced all the door interlock switches, which tested fine for continuity and function to begin with, and the primary fuse. The breaker still trips on opening the door during heating. Apparently that's not the problem.