This question is kinda tricky. So I'll try and do the best I can.
OK, we bought a foreclosed house in Ohio about one month ago. It's a duplex that's about 90 years old. The house is doing well for the abuse it has been though being vacant for the last four years with winterization done after the fact.
We have had the power on for almost a month now with no problems. Well the other night for some reason the lighting stopped working in the main bedroom, second floor hallway and Dinning room. Checked and none of the breakers have been tripped. Reset them all to make sure.
Heres the tuff part. The Dinning room and second floor hall light have a switch on each floor. So two switches on the dinning room stair case and two in the hallway upstairs. After fishing around and knocking out the ceiling in the kitchen. There are five wires running close to one another. They run throught the joists going from the kitchen ceiling to the switches on the second floor down though the ceiling of the dinning room to the switches on the stair case.
I have taken a multimeter and checked all the wires with of course no voltage. Now since there are five I am guessing one is the hot and rest are the neutral? Or is it one is neutral and one is hot? Whats also tied into this is the lighting for the back porch and ceiling power for the fan in the main bedroom also on the second floor.
I can't seem to find where it starts and where it ends. As you guess it's the old knob and tube wiring. What also makes it hard is the breaker panel is new and tied into the old wiring at junction boxes. Where would be a good place to start looking?
The place is going to be used for rental property. So I have a little time and would like to learn this. In other words I am not calling a electrician. LOL
I can post some pictures if you like.