I doubt this can be answered with the limited information I have been able to find out so far, but I'll give it a go. Maybe something will
My parents have a 3 story house built in 1915. A 2nd floor bathroom has an older heater/light in the ceiling. On the light circuit of this is also a vanity light above the sink. On the wall is double switch. About 1 foot away is a GFI, in an adjoining closet is a light and receptacle as well as a light and receptacle in the attic above.
My dad had a vacuum plugged into the receptacle in the closet and lost power. At this point, the heater still has power, but nothing else. I figured maybe a GFI tripped, but there isn't any power going to it.
I opened up the heater/light unit and there is a black ROMEX® 12/3 w/ground coming in. The black wire goes to the heater and it gets power. The red goes to the light and it doesn't. I don't see any other wires coming or going to this unit. That would somewhat tell me that this is fed via a switch. Correct??
The strange part is I tried tracking this wire down to the basement and found a black ROMEX® 12/3 wire that had no power with breaker off, but it does get power when turned on. I tracked it back to the breaker box and of course the black wire is connected to a 20amp circuit, but the red is capped off. So logic would tell me this wire makes a stop somewhere else before going to the heater/light.
The crazy part is I can not find another 12/3 black encased ROMEX® wire going into any other junction box. Everything I open up has 12/2 white wire.
The double switch has power going to the hot leg of the heater switch, but the tab between the two switches appears to have been broken off and there is no power going to the light side. There is a fair amount of knob and tube wire in the house, but so far I haven't "seen" any on this circuit.
Any ideas?? We are trying to find an electrician, but at the same time trying to figure this out to be on the safe side in the interim. It just makes no sense to me that a black ROMEX® 12/3 wire would come from the breaker box and a black ROMEX® 12/3 would go into the light/heater unit, but no where else....
Thanks for anything??