I just finished a minor kitchen renovation, reconnected the 220V to the stove, and the when I turned the breaker on for the stove circuit at the main panel and the one on the smaller dedicated panel under the cabinet at the stove I had no power. Neither breaker tripped. I quadruple checked my wiring at stove and it is correct. I traced the problem to a bad breaker – I'm getting continuity on one pole but not the other. I find this odd because I've never had a breaker fail before and was wondering if there was a fault in my wiring. I checked that there was no short between the two hot wires and the ground between the dedicated breaker and the stove connection, and there's not. This leads me to believe that the breaker just failed due to maybe drywall dust getting into it or it just failed mechanically. Is this possible? I assumed that if there was a real wiring fault it would have tripped one of the two breakers on that circuit when I turned them on.

i have an old house with K&T. I need to extend it to a new service panel (just lights and plugs). It's not practical to replace all of it with romex and the K&T is in very good shape. I know K&T has higher amperage. What size romex should I use? Can I use 14/2? What does CA electrical code require? Thank you!!