Originally Posted by
evankirkhart
From what I understand, I think some wires are repositioned. When a light is controlled in two locations, it is known as a 3-way switching system. These are the wires that should be in the boxes:
In Box A: constant power coming from the panel, and two wires that connect this box to the other switching location. These wires are usually black and red, and are called travelers.
In Box B there should be the cable going to the fixture and the travelers from Box A.
The object is to make this 3-way switch into a single-pole switch. With everything installed, the constant power (downstairs) should be connected to one of the traveler wires, sending constant power to the upstairs box. If you use a black wire, be careful to note which cable the black wire belongs to. Then, connect that wire to the dimmer, and the wire that goes to the fixture to the dimmer as well. Cap off any unused wires. Always ground metal boxes and devices. I noticed that a bundle of ground wires was missing a wire-nut, that is necessary for a good connection. A neutral wire dimmer will not solve this issue. The no-neutral dimmers must have a load connected to them in order to function while this is not necessary for neutral dimmers. If you followed these steps and it still doesn't work, call Customer Service. They are very helpful and will make sure this issue gets resolved.
Hope this helps,
Evan