Disclaimer: I am not an electrician. (Though I have considered it as a potential career.) I have learned wiring from friends and books and the following is my knowledge of how to replace old switches and outlets with new ones. If you need to do electrical work, I highly recommend doing your research or having a professional help you.
Ok, that said, today I swapped out the switches and outlets in the three upstairs bedrooms in the house where I am living. One thing I learned is that it takes a lot of patience to work with wiring, especially when you have to work with a decades old system. Having the right tools helps. I used a voltage tester, drill, screwdriver, needle nose pliers, wire stripper, and utility knife (for cutting off old plaster chunks). I gathered these tools along with the new outlets, switches and plates in a box. Then I switched off the breakers corresponding to the bedroom outlets and switches. Luckily everything is well labeled so I didn't have to do any back and forth testing.
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| New (left) and old (right) dimmer switches |
In the first bedroom, I started with the switch. With the voltage tester, I checked to ensure there was no incoming power. With that confirmed, I unscrewed the cover plate and then the switch plate. I pulled the switch out from the wall box with the attached wires, one hot and one neutral. The ground was connected to the switch box since the existing switch lacked a place to secure it. I unscrewed the black (hot) wire first, then the white (neutral), then I freed the ground wire with the pliers so all wires were ready to be attached to the new switch.
I learned to connect the ground first so I began with the ground wire which I shaped with the pliers to have a small curved hook at the end. I hooked the end of the wire around the green screw so that the wire curved clockwise. I did it this way so when I tightened the screw, the clockwise direction of the tightening of the screw would match the wrapping of the wire for a more secure attachment. Then I attached the neutral wire to the silver screw and hot wire to the gold screw. (The gold screws were labeled at hot on the back of the switch which was helpful to reaffirm what I thought to be true.)
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| Old dimmer switch wiring |
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| New dimmer switch wiring |
After all three wires were tightened to the screws, I pushed the switch back into the receptacle, screwed in the screws with the dill (since they are longer screws). Then I used the screwdriver to attach the new metal cover plate. I like to use a screwdriver for this since the screws are usually short and it reduces the chance that I will accidentally scratch the plate with the tip.
Then, I started on the outlets in the room. I used the same process as for the switch except some of the outlets had two hot wires and two neutral wires depending on their original wire run sequencing. The outlets with more wires were a little more complicated, so I made sure to keep track of which wire was attached to where on the old outlet so I would reattach it to the same spot on the new outlet.
I repeated this process in the other two bedrooms. My room has a dimmer switch which was actually no more complicated than the other switches. In four hours, I had rewired 3 switches and 7 outlets! Then I just had to check to see if they all worked. I went back to the basement to switch on the breakers I had switched off and then used the voltage tester along with a lamp, outlet strip, phone charger, etc. to check the outlets. I flipped on all of the light switches and they all turned on, even mine with the dimmer. Success!