Understanding bedroom wiring in old house


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Old 06-23-14, 06:31 PM
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Exclamation Understanding bedroom wiring in old house

So I was going to remove a flush mounted ceiling light with a ceiling fan in my bedroom. I live in a townhouse in Alexandria, VA that was built in the mid 50s, I believe 1954. Ignoring the problems that come with mounting the correct box to support the fan weight (different forum and different problem) I want to make sense of how this was wired prior to install. Basically due to the age of the house I have a 2 conductor no ground wiring system (to my knowledge...haven't opened an outlet yet). The wiring for the light had three conductors, a red, white, and black. So to me that is the hot, traveler (hot), and neutral. I pull down the light (after power is off of course) and find that the red is terminated off (see first picture), the blacks (yes multiple), and the whites are all wired together. To confirm, the blacks are all wired together to the hot for the light and the neutrals are wired to the white wire out of the light as well.

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I find that there are two cables (one white one black each) running into the box other than the one from the light switch (white red black). My first thought is that they used it as a junction box of sorts. I open up the light switch expecting to see the red wired to the incoming black power and then tied off to one of the terminals (so it is always hot). I also expected to see the black that goes to the light tied to the other terminal and the neutrals tied up. I find the (see second picture) the opposite. The red is directly tied to one of the terminals and the blacks are wired together at the other terminal (one incoming power one to the light).

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This really confused me but then it got worse.

If the blacks in the light switch are all wired together and the red is terminated off, why isn't the light always on since the red would be the switched hot? On top of that the blacks in the light itself are wired together and then fed to the hot light wire. That confuses me even further. Where are they from and shouldn't they just hot continuously or is this some weird loop?

One last thing just for safety's sake, the ground copper is tied off to the holding bar that is screwed into the ceiling box which is grounded to....what? Doesn't this make the outside of the fixture potentially a shock hazard? I did hold up a voltage detector to the frame and it went off (in the other room...get to that in a min) but it isn't exactly a superbly expensive detector.

I did open up another room and of course it was wired completely opposite but correct in my head, black to incoming power to one terminal, red on other terminal, except the black in the light was terminated off and the red led to the black for the light. Please note that these aren't 3 way switch and have only one light switch and light. The second room also had the mystery incoming and outgoing wiring.

Last thing to think about, I have to wire a fan up to this monster so I was thinking (prior to looking at it) to wire the unswitchable black to the motor and switch red to the light. Is that correct? I haven't done anything with the fan yet because I wanted to get this straightened out first.

Here is my best paint draw up of what I found originally. I swear I found it this way but everything is telling me I am crazy.

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Help.
 

Last edited by ray2047; 06-23-14 at 07:19 PM. Reason: Add images.
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Old 06-23-14, 07:23 PM
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Using a multimeter, preferably analog, (but not a non contact tester) you need to determine which cable when disconnected is hot.
 
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Old 06-23-14, 09:01 PM
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Be sure to change the box and brace after identifying the wires.
 
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Old 06-24-14, 06:13 AM
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Alright I can do that but do you have any recommendation on how I should tie them up or keep them loose that is safe when I turn on the power? Just want to check because I have a general idea but rather have your input.
 
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Old 06-24-14, 07:39 AM
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The wires will pretty much stay wherever you place them after opening the splices. Do not let the bare ends touch anything else.
 
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Old 06-30-14, 01:13 PM
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Sorry for the delay in response, had some family emergencies to take care of this week.

Anyway, using my drawing as a reference: The black coming from the left is always hot when the switch is on or off. I checked every permutation between the wires while the switch was off and the left black measured 120V against the black wire coming off the light switch, the white wire from the light switch, and the white wire from the left. Nothing else showed 120V.

When the light switch is turned on:
All the above is still true except now I show 120V pairing the black wire from the left and the red wire from the light switch.

I am willing to rewire this to whatever y'all say for a ceiling fan that ensure the safety of the house and me. I have included a picture of of the ceiling fan wiring directions for your reference so that I can ensure a proper installation. If I need to do anything else or provide more information throw it at me.

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Old 06-30-14, 01:48 PM
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Before you do any rewiring......

Be sure to change the box and brace after identifying the wires.
You need a ceiling fan box.
 
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Old 06-30-14, 01:53 PM
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I plan on replacing the ceiling box, just trying to get my ducks in a row.
 
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Old 07-06-14, 03:14 PM
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Can anyone help me out based on the new information? Really could use some assistance, thanks.
 
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Old 07-06-14, 03:39 PM
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Didn't reread your whole post but red and white should be switched power to the fan. Fan blue and black to red. Fan white to house white.
 
 

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