Electrical – Adding a ceiling fan single switch in a box with 3 way switch in older house

ceiling-fanelectricalswitch

Sometimes I love our house and sometimes I don't..and many times I don't when I am trying to do some electrical because it is not at all straight-forward.

House was built in 1943, has older silver colored braided insulated wire with 2 wires in it, 1 black and 1 white.

I have done a bunch of work on electrical, replacing when I am able and it is needed, and running new circuits. A couple of summers ago I installed a new 40 panel box. Everything is working well.

So I am trying to add a ceiling fan to our living room. I ran a new 12/2 wire from fan to a newly converted (single to double) box on the wall. The other switch in the box is a 3 way switch that actually switches an outlet on and off and has 1 partner switch on opposite wall.

First issue: For whatever reason, some of the old wire is reversed and some is not. What I mean is, where normally black is hot and white is neutral this particular 3 way switch is indicating white as the hot and black being neutral. Well, let me take a step back. The switch I am referring to has 3 wires connected, a white to the top brass screw, and black to the bottom dark screw, and then a red on the other brass screw. When using a non-contact, I am getting white reading as hot and nothing on the black unless the switch is in the opposite position (in which case both white and black are reading as hot). When I disconnect completely from switch, only the white hits as hot.

So, the fan that I am adding is going to go on a single pole switch so how exactly should I approach connecting this? I know there are a couple of ways. I was thinking of just connecting the black coming from the fan (which is hot for the fan) to the switch and then connecting a single length of wire as a jumper between the hot on this switch and the 3-way switch. Is this proper?

Finally, I have no idea what to do with the neutral coming from the fan in this situation. Which wire do I need to connect this to? I know it is the neutral and am unsure how to handle this situation when connecting to 3 way switch.

Here is a diagram:

Diagram

Best Answer

You don't have a neutral at the switch. White is a traveler, and should be marked in some way to indicate that it is not a neutral (but is likely not marked). Red is the other traveler, and black is common (either attached to power or the light, depending on which switch it is). Multiway Switching can be confusing, and is the subject of many questions on this site.

This is likely what the circuit looks like

enter image description here

You're describing the wiring at switch 2, where the black wire is only "hot" when both switches are in the proper state (both up, or both down. Unless one is installed upside down). When the switches are toggled, one of the travelers between them will be energized.