We're renovating a hundred-year-old house that's been through several owners and has hodge-podge wiring. I've redone all the wiring from scratch in the rooms we've re-walled. Everything has gone well until I messed with some old wiring in the kitchen..
Quick version: I replaced an outlet on the outside of the house that was part of the kitchen circuit because it killed part of the circuit and I have no idea why. Now I've killed the whole circuit by pressing reset on one of the GFCI's and now I'm really lost.
Long version: I have already replaced all the counter outlets with GFCI, and everything's been working fine for months (plug-in tester lit up correctly on all of them), so I know they're wired correctly. Yesterday I went to replace an exterior outlet (outside the kitchen wall) with a GFCI, but when I turned the circuit back on, half of it didn't work. It's an old house so each circuit has A LOT on it. This one has 13 outlets and 4 ceiling lights. From what I've been able to work out from looking under the house is that the circuit appears to start in the middle of the kitchen, go along one wall then up to the ceiling for the lights, then (I believe) it comes back down into the wall on the other side, splits in two somewhere, forms two legs, and dead-ends in two places. What's strange is that the outlets I killed are all upstream of the one I was working on, or they're on the other "leg" of the circuit. I worked my way backwards to the first outlet that was working, replacing all with brand new outlets, wiring exactly as I found them. No change. Tonight, trying to think of everything I could have possibly not tried yet, I pressed the reset button of one of the dead kitchen GCFI outlets and the rest of the circuit blew. Tried to reset the breaker and it made a sparking sound and stayed off. Now the whole kitchen circuit is dead, and I don't know where the problem is.
What is happening?? I was meticulous with matching the old wiring once things went awry but I was on autopilot replacing the first exterior outlet. It's possible that I didn't notice some funky wiring and messed it up by installing it "correctly." I have come across some non-switched wires that had the white and black reversed in other parts of the house. Could a hot and neutral be reversed here, would that cause this kind of problem?
I'm pretty sure I need to replace the breaker now, but if I don't fix what's wrong I'll just blow the new one too..