Sometimes electricians carry the 3-wire from one switch to the other via the light's box, to make a shorter run or just because it's convenient to route that way. If that's the case, then there should be a grand total of eight wires (excluding grounds) entering the light box: * 2 hots (one black, one some other color) and a neutral (white) from the first switch. * 2 hots (one black, one some other color) and a neutral (white) from the second switch. * A hot and a return (not a neutral) from the second switch. One of these should be black and one should be some other color. However, if the circuit is romex, one of them will probably be white; if so, it should be painted black or have black tape on it near the end. These would be the two wires connected to the light fixture. What it sounds like to me is that the light box is not really "between" the two switches in terms of how the circuit is routed, even though it may be physically in between. My guess is that the yellow is the switched hot, and the white and green are what you expect. I'm not sure what the always-hot black is doing there. Possibly at some time in the past, there was a ceiling fan installed there with a light, and the yellow was connected to the light lead of the fan so the light could be switched on and off with the wall switches. The black might have been connected to the motor lead, and the fan turned on and off via its own pull chain. That's kind of unorthodox, but in an older installation, it wouldn't surprise me.

That's not the wattage rating. It's the voltage. 600V. If you are using 14/3 for the switching you might as well use #14 for all the wiring. It is good for 1800w (nominally).

Hi Greg, Could I bug you one more time? Old fan: 3 wires - black for fan motor, red for light, white neutral New fan: 2 wires: black for motor, white for neutral I've got three wires at the ceiling...black (always hot), red (controlled by switches), and white. If I hook up fan unit to black and white, switches are now wall ornaments. If I hook up to red and white, I can shut off power to the unit. So, I will be not using one wire at the box. Am I understanding this correctly? The documentation/manual with the fan assumes hot and neutral at the box. Thanks! :)

I didn't really read the subject line. Here's another interpretation: If you are trying to control 2 lights (both going on/off at the same time) from 4 different places, then you don't just use 3-way switches. You need 4 way switches too. I think it needs two 3-ways and two 4-ways. I'm sure you can google it to get a proper wiring diagram.