I've isolated the problem, but unfortunately I'm not hip to all the terminology to ask the appropriate question and decipher the answer. I am going to break it way down to (try) to avoid confusion
Long story short the same 15A AFCI (arc-fault) breaker was tripping when I turn on fan in bedroom #1 or #2. I pulled the panel cover off to see that there are two hot wires wired into one 15A breaker. One red and one black, then the white neutral on the backside.
And there is one 15A AFCI breaker that is completely empty even though one was labeled for each bedroom.
Bedroom 1 and 2 share the same cable (series of wires), its a 4 wire cable consisting of red, black, white, and copper.
So both the red and black wire from the same cable (series of wires) is run into the same breaker, powering two rooms with one breaker.
I put one of these wires, we will say the red one, into the empty 15A breaker. The only problem is since they share the same cable I don't have a second neutral to wire into the back of the newly occupied breaker so everytime I turn the fan on in the room now powered by the red wire the breaker trips.
My question is can I wire nut two new wires into the neutral wire and run one each to the back side neutral nuts in the breakers?