Help needed with knob and tube fed light.

[shanefish]

Firstly, I am a novice and would have hired someone if I could afford it, but I cannot and have opened up my kitchen walls and am in need of some assistance if anyone can help.

I have a kitchen light with 2 K.T. wires coming in and out, one hot and one not. The light is controlled by a switch at LOCATION 1 via a wire named LINE 1 with a black and white wire attached to a 3-way switch (the white one to the common and black one to one of the others.) There is nothing connected to the other screw. This LINE 1 was added prpbably in the 50's and travels under my floor into a box on the opposite wall in the kitchen. The white from LINE 1 connects to another wire and travels up the wall at LOCATION 2. However, at LOCATION 2, the black wire from LINE 1 meets up and is pig-tailed to a wire (LINE 2) and also pigtailed to a switch at LOCATION 2. It appears LINE 2 is split going up and down in the wall and I believe the upper is the incomeing hot wire. The switch at LOCATION 2 does not appear to control anything and is only a 2-way switch.

May I add that at LOCATION 2 there is a mystery wire that has no juice, travels both up and down in the wall and has a pig-tail at LOCATION 2's box but that end is just capped off and goes no where. Could this have been the common in an old 3-way box. I believe the electrical was put in the 1920's or 30's, then upgraded in the 50's and 70's. I have wires literally all over the place. I cannot reach the knob and tube wires to pull new wire but can probably run all new if I can figure out where the hot wire comes in I guess. My wife is about to kill me and I need some advice if you can help.

I have a diagram and photos if that helps. I find it odd that the power comes into one switch and is pig-tailed to another switch and it is that switch which controls the light. I am baffled even after staring at it for hours last night.

[ray2047]

Post your photos to a site like Photobucket then post the URL here. My first impression reading your post was that the light was originally wired as a a three way using a method common in the days of K&T wiring but now illegal and was corrected when rewired. In the K&T days a three way was sometimes done with regular switches by interrupting the neutral with one switch and the hot with another.

Your bigger problem is that now that your walls are open your jurisdiction may require you to replace all the K&T wiring. Note by code you can not add onto or extend K&T. You can for the most part only leave it untouched.

[Bill190]

What are you wanting to do?

Add outlets/circuits?

Remodel kitchen?

Fix existing circuits?

(Why did you open up the wall?)

[shanefish]

Location 1 is where the current switch is for the kitchen light. I wanted to install a 3-way switch at another location, so I opened up the outlet to investigate. I am doing a semi-remodel of my kitchen. Nothing major, just new outlets and surfaces mostly. Location 2 is where i found the incoming hot wire for the overhead light. It is pig-tailed to a 2-way switch at Location 2 (which when switched does nothing) as well as pig-tailed to the black wire from the other switch. Location 1 has a 3-way switch with only 2 wires hooked up, a white to the common and black to one of the other screws. At location 2, wires #1 and 2 are to an outlet I am re-routing to service my new microwave. Wires 3 and 4 were attached to the useless switch. Wire 3 is the black from location 1 and 4 is neutral and goes up inside the ceiling. Wire #5 is pigtailed to the white from Location 1 and travels up inside the ceiling. Wire #7 goes up and down the ceiling and is pigtailed, but taped capped off at Location 2. Wire #3A is hot and brings power from up inside the ceiling and is pigtailed to wire #3 and to the useless switch at Location 2. 3A also travels up and down the wall, but I traced the lower wire and it appears to not be hot in the basement.

Did I help or just add to the confusion?

[ray2047]

Some times it is quicker and better to just abandon what is there and go from scratch.

Reasons to abandon:

(1) K&T can't be altered or added to.

(2a) You have ungrounded cable for a kitchen receptacle. Needs to be grounded.

(2b) Kitchen receptacle probably 15a/#14. Even if not counter top should, best practices, probably be 20 amp/#12.

(3)To hook up a three way correctly you will need to run #14 (or #12) 3 conductor NM cable but this can't be connected to the existing K&T. (See reason 1.)

You say conduit on your diagram. That might provide grounding. If it is rigid and not old style BX cable you may be able to run new wires. Are you sure you have K&T and not BX?

[shanefish]

I have no conduit nor armored cable anywhere in the house so far. I have run groundwires to all of the outlets in the bathrooms and kitchen.

[Strategery]

I'm no expert, but as Ray said, it may be best to start from scratch. Modern (not 50's modern) kitchens and electrical codes require more circuits and safety features than you have now. With a little planning and research, this can be a DIY project.

You should read a couple of books on wiring, then plan your project. Although not required for a counter-top microwave, I would put it on its own circuit. New electrical work will cost more than you planned to spend, but it will be worth it to have a safe and functional electrical system in your kitchen.

[Bill190]

This is advanced wiring for electrical experts who really know their stuff! And even then it can take quite a bit of study, tracing wires, and testing to figure out what each wire and connection is for.

Modern romex wiring is somewhat easy for an electrician to figure out because you have bundled colored wires and wire nuts. Everything runs in a logical manner - point A to point B. Also easy to disconnect a wire nut and trace out a circuit.

But K & T can be "spaghetti"! You may have 3 or 5 wires all the same color running next to each other. Sometimes just 1 wire running by itself! Huh? 1 wire? What are they doing here??? Then the splices are impossible to disconnect for testing. They wrap around like a spring.

Then homes with K & T have been around for a long time. There may have been additions - things added and removed. I've found wires spliced into other wires, then follow these wires to a dead end. Just cut wires which were taped and left hanging in the wall or ceiling. (You find this stuff when you tear out the walls.)

So I think it would be quite difficult or next to impossible for someone to try to help you figure out your old wiring via the internet.

You would basically need to make a circuit diagram of your existing wiring. What all goes to what. Then it would become clear. But you might have to tear out your walls to find what all goes where.

Actually a similar problem is with electronic circuit boards. There will be one copper connection on a circuit board which connects to 6 different things. You can't easily disconnect things to test each individual thing.