So, I recently attempted to install a new light fixture to old wiring with no success. I have no electrical experience, so forgive me if this situation and the following questions are either stupid or redundant.
The old — three light — fixture included three black wires, three white wires, a red wire and a blue wire. It was replaced with a new fixture using just one black, one white, and one neutral wire.
I connected the new fixrure's single hot and neutral wires to one black and one white wire respectively. As the old wiring included no recognisable ground wire, I simple attached the new fixture's copper wire to the green grounding screw on the new mounting fixture.
The light does not come on when I turn the switch.
Do I need to connect all existing black and white wires to the corresponding single black and single white wire on the new fixture? Should the red and blue wires be attached to anything else or left unconnected and capped? Is it normal that there appears to be no ground wire included in the old existing wiring?
To answer ThreePhaseEel,
Best Answer
You hook the new lamp exactly the way you found the old lamp
All the white wires from the old lamp went to one place. That place is where the white wire goes for the new lamp.
All the black, red and/or blue wires from the old lamp went to one place. That is where the new lamp's black wire goes.
You don't mess with anything else.
Particularly, you do not group wires by color code if they weren't before. Color codes do not have the purpose you wish they did, they don't tell which wires go together or what the wires do. Cable colors are part of manufacturing the multi-wire cables, because making all the wires the same color wouldn't work.
When you see wires bundled together, those wires are not "spares". They are already engaged in other tasks and need to stay the way you found them.
Oh. You messed with anything else.
Well, the good news is, given the blue wire and combinations you stated in your comment, this work is plainly in conduit, so there's a fair chance the wire colors are in fact meaningful. What a refreshing change, Usually they don't mean much.
The ground will automatically get picked up via the mounting screws when you mount up the harp. (This "via the screw" method only works on lamps and switches, not receptacles). So grounds are no worry, I love metal conduit.
The whites look OK, with one remotely possible, critical exception.
Based on what you say it's the blue wire. They were kind enough to color code the wires and it looks like blue, being a solo, is for this light.
You could also try the red, but Ihave a feeling that's for the fan.
Beyond that you are going to need to bring in a pro. Do not just repeatedly experiment. You are likely to discover combinations which do what you want, but that create a dangerous situation.