I have a general understanding of electrical and some know how, but I moved into a place at the beginning of 2021 and 3 days ago I come home and try to preheat the oven and nothing. I tried the broil setting and it wouldn't work either. So I figured I would boil some water to cook pasta if the oven wasn't cooperating, but no stovetop elements would work.
I had power because the clock on the display still worked and the oven light turned on. It dawned on me that those are the 240v functions of the appliance and that the things that worked only ran on 120v. Thinking that 1 pole of my 2 pole 40amp breaker was no good I checked my breaker panel and found it was a CEB panel and all the breakers were Sylvania make, the 40 amp one specifically was a 240QBH so I got a new 240QBH breaker made by Eaton (looks exactly the same and has the same functionality bolt on 2 pole 40 amp).
I replaced the breaker and was hopinh that was that, but my problem was persistent. Still no 240v functions on my stove/oven. So I tried to troubleshoot the problem with a multimeter starting at the back of my appliance and found that indeed it had 120v on each leg to neutral or ground but bothe legs together gave me a 0v reading.
I did the same to the receptacle and replaced it at the same time with a new one also checking the wiring to it and same as what I saw on the appliance, so no problem there. Finally I went back down to my breaker panel and checked each hot to the neutral panel and same thing there 120v each hot but when I put my leads on both hots coming into my breaker 0V reading.
I changed it back to the old breaker while I was there, seeing as it was $85 I had just unnecessarily spent and would like that money back and it obviously isn't a bad pole in the Sylvania QBH240. So I read some other Q&A postings in here and know that you would say that both hots are most likely on same leg, How would this occur all of a sudden and how can I fix it now?... Or troubleshoot it further? I seem to be at my wits end but cannot afford outsourcing it and I need to be able to cook. Any advice is appreciated.