So, our garbage disposal hadn't worked in a while. There was a switch under the sink which sorta worked at first, then had to be held in the "ON" position to work, and then had to be held in the "ON" position harder to work...and eventually it simply stopped working.
The existing gang box was grungy, so I elected to replace the whole thing. Went to Home Depot, picked up a gang box
, a switch
, some wire
and a faceplate
Get down under the sink, and...crap. I realize I really don't want to replace the existing wire, because I can't even see where the power source is
. That wire sneaks away behind the dishwasher, where I can't get at it for the time being. So, fine. We'll leave the existing wire in place. It's dirty, but it's not bad...12-3 NM.
Unscrew the old faceplate, set it aside.
Unscrew the old switch...the guy used two different screws. And that bottom one is not the right kind of screw...no wonder the thing had some spring to it; it wasn't attached. Anyway, detach and set aside.
Neutral line was hooked together with a big red wirenut. Detach and set aside.
Unscrew the old gang box. The guy used drywall screws to screw it into particle board? Weird. Unscrew the insert clamps and set them aside.
Screw in the new gang box, use 1" #10 sheet metal screws. Pop out the bottom and the bottom-right knockouts...oh, right. Insert clamps. Go to insert the insert clamps...er, these are a bit small. Oops. Hm. I'm going to need 1/2" insert clamps...except I didn't know what they were called at this point, so I pored over the book I got for home improvement projects
, and found what they were called. Also saw that you're supposed to use a yellow wirenut when connecting two 12ga solid-core wires, rather than a red one.
Go back to Home Depot, pick up 3/4" insert clamps
nd a wirenut kit
Come back, set up the insert clamps, get everything wired up, go to screw in the switch...crap. The bottom screw of the switch bumps into the insert clamp for the bottom knock-out. No wonder the previous guy used a different screw for the bottom portion of the switch.
Well, if I don't do this right, something's going to get screwed up in the long run. I have to use a side knockout. And per code, I can't reuse a box with a knockout knocked out but unused...not even with some kind of plug. So, back to Home Depot to pick up another box
, this time with 1/2" knockouts, and a couple 1/2" snap-in insert clamps. (Which aren't turning up on their website.)
Come back, remove the old new box, put in the new new box, punch out two side inserts, pull the cable through and tighten things down, wire up the switch, screw in the switch, screw the new faceplate on, energize the circuit, and...I have a working garbage disposal again! Yes!
After a bit, I realized why it stopped working in the first place. With the old setup, the bottom of the switch wasn't affixed at all, so the springiness was the wiring compressing and decompressing. With the neutral line connected with a too-large connector, every time the wires were pushed, the connection got looser, to the point where they weren't connecting at all. Of course, the bottom of the switch wasn't affixed because the insert clamp on the bottom was in the way. So, if either a decent wire connector had been used, or if a proper-sized wire nut had been used, the wiring probably wouldn't have failed.
(Still plan on moving the switch, but not at this moment.)