I have an AFCI circuit breaker on my attic circuit. My attic was finished after the house was completed by a previous owner who did extensive re-modeling and cosmetic updates. I was adding a ceiling fan to a bedroom on my second floor NOT on the AFCI circuit. I found the ceiling light was wired to (uninsulated) ground INSTEAD of neutral (white). So the wiring for the ceiling light on the second floor bedroom was circuit black to light to circuit uninsulated. I changed it to connect the second leg of the light to the circuit neutral (white wire). I found that when I turned the light on, it immediately tripped the attic AFCI circuit, which is supposed to SEPARATE from the bedroom, and did not cut power to the hot the second floor light was on. What is going on here?? Did someone previously maybe mix neutrals in a junction box somewhere between these two circuits??

I recently installed an in line water heater at my house. I had to put in a bigger breaker to do so (and run wire). There were two empty fuses on the right side of the box. I moved two from the left to the right and then moved all of the breakers up to make room for that 60a. Now my dryer won't turn on... the light comes on when you open the door but when you try to turn it on nothing happens. I asked one of my wife's friend who said he could help and he said something about the left and right side being different voltage but I always thought the number of wires determined that. So now I'm just confused and want to be able to dry clothes again. Can anyone help me.