*NOTE: all advice and suggestions are given only for illustrative purposes; anyone performing any work is responsible for his/her own actions. Always remember, safety first. Also remember: if it isn't yours, don't work on it. If you're renting, call the super or the landlord - the physical structure is his responsibility.
All right, let's get this party started.
Isn't electricity dangerous?
You bet! Don't believe me? Just remember what it feels like to put your tongue directly on both contacts of a new 9-volt battery. YOW, and that's less than a tenth of household voltage. The 9-volt stings like a bee, 120v will light you up. Don't be misled: it might be "just" 120v, but it can kill you.
So what do I do, to not wind up a chicken nugget?
Find the fuse box, or the breaker panel, and locate the fuse or breaker that corresponds to the circuit you're working on. The fuse box is a shallow metal cabinet, inside of which is what looks like the bottom ends of a bunch of light bulbs. Those light bulb bases have a heavy glass top so you can see into them (usually), a breaker panel looks like it's full of heavy-duty light switches. Hopefully, these things are labeled so you have an idea of what you're working on.
Plug something in to the circuit where you're working, and remove its fuse or turn off the breaker. Breakers are way stiffer to move than a light switch, so don't be surprised if it takes a little effort. Check one circuit at a time, then double-check it so you're certain the circuit you're working on is turned off. Turn one off, check it, turn it back on. Turn off the next one. Repeat as needed until you've isolated your problem circuit.
If your panel doesn't have labels telling you what's what, now's a good time to make some notes. It speeds things up next time you're in the box.
Usually when I'm working on a circuit, once I'm certain it's turned off, I'll check it with a voltmeter or other device, just to confirm One More Time.
Okay, it's off and we're sure it's off. What are we doing here?
Well, there's good reasons to turn off a breaker and work on your own wiring. A lot of what goes on with your household electricity is really straightforward stuff. And even better news, a lot of the parts are really affordable.
Well, I've got this one outlet that kinda crackles and hisses sometimes. What's up with that?
Hey, an easy one! First, be sure it's turned off.
Once that's done, remove the outlet's faceplate and set that aside. Loosen the screws at each end of the outlet and pull it out of its box. Don't go crazy, the wires are still attached.
Look at the back of the outlet. Do the wires go directly into holes in the back of the outlet? If so, good news, that's probably your entire problem. Spring-loaded contacts inside the outlet make contact with the wires, and the springs fatigue over time, eventually allowing things to flex and not make good contact. There's two ways to get the wire out of there:
1) Remove the wire by inserting a small, thin blade into the slot next to the hole. That'll release the spring, and you can pull the wire out. You may feel like you need three hands for this, and it wouldn't hurt, but one person can do it. After you've done a few, you'll be able to do it one-handed.
2) Cut the wire close to the back of the outlet, and strip a new portion for attaching to the new outlet. If you've got big electrical boxes inside your wall and plenty (ten inches or more) of slack wire, go for it. You get some stripping practice that way.
Whoa, stripping. Okay Mr. Handyman, start your music while I get my dollar bills...
Don't be flippant, this is important. You can use wire stripper pliers made for the job, or you can whip out your pocketknife and either whittle the insulation off, or scribe a line around the wire and slide the insulation off. Whatever you do, try not to nick the wire, that's important.
How much do I strip off the end?
Peer myopically at the back of your new outlet and you'll see it has a handy little example of how much of the end should be stripped. Most wiring devices are like that, by the way.
Hey, my new outlet has those holes on the back. Can I just poke the wire in and be done?
Yes and no. You can, and it would work - but like I said, the sprung contacts fatigue, and you're back where you started. I always use the screw contacts. They make much more contact with the wire, and grab really well.
Wait...which wire goes where?
Easy: "White to bright, black to brass." The white wire is the neutral wire, and it goes to the "bright" screw, the silver-colored one. The black wire, the "hot" wire, goes to the brass-colored screw. If you've got a bare copper wire going to your old outlet, shift it over too: it goes to the green grounding screw.
No ground wire? No worries: the outlet is also grounded through its own metal chassis, directly to the metal electrical box. If your wiring is really old, though, and the old outlet had no ground and there's no provision for one inside the box, you've got some problems, and may need to call an electrician if you want to keep everything up to code.
Speaking of code...am I violating anything by doing this? You're not an electrician.
No, I'm not. But unless I misread the code - hopefully someone will tell me politely if I have - you can do this kind of thing on your own home if you're not making significant changes or receiving money for it.
So far we're up to three screws and three wires. That sounds minor enough.
It certainly is, and let's crack on.
The light in here is lousy - I turned off their power at the breaker, remember - so I can't see which screw is "brass" or "bright."
Flashlights are your friend. Go find one. Barring that, the hot wire goes to the shorter slot of the outlet - look at 'em, one's a little longer than the other. Hot goes to short, neutral to the longer one.
Okay, where is this "black" wire? I have white, copper, and red.
That's okay - the red one is the hot one. You see that sometimes. In virtually every case you see, the white wire will be the neutral; a bare copper is always ground. Any other color will be the hot one. If you see more than one other color inside the box, they're both hots - two different hots. More on that later.
Bend the bared end of the wire into a J shape, and hook it around the screw in a clockwise direction. Clockwise, so as the screw head begins to drag on the wire as it tightens, it pulls the wire into closer contact around the shank of the screw. Contact is the name of the game, and more = good. Repeat for the other wires, and tighten down the unused screws, too.
Gently fold your wires into the electrical box, screw the new outlet's screws down, and reinstall the faceplate.
Turn the breaker back on. Test it with a load: lamp, voltmeter, whatever. Everything A-OK? Cool, you're done.
Done? That was easy!
I know, right? Call an electrician to do that and there's that danged "trip charge" again. So far you're only out $2.00 for a new outlet, $7.50 for a wire stripper, and maybe as much as $30 for an electrical tester. You're still ahead of the curve against the electrician, and the next time something goes all sparkly, you've got the tools already.
Hey, speaking of sparkly, I have a light switch that throws sparks. What's up with that?
That switch is worn out. Time to replace it. Same as last time, turn off the circuit, and test to be sure. Faceplate off, mounting screws out, pull the switch out. Let's see what we see.
There's two black wires going into this thing!
Right! But really what it is, is: the black wire goes in, and then comes back out. Think of it being like a pipe, and the electricity is water. The switch is a valve that doesn't allow the current to flow, so it just stops at the switch. The white wire goes right on to the fixture; you could put a switch on the white wire but that does violate code. Besides, putting a switch on the neutral really throws some sparks, and will wear out a switch very quickly due to heavy arcing.
Remove the black wires from the old switch, and attach them to your new one. TAKE A MOMENT to orient the switch correctly. Few things are more annoying than installing a new switch and realizing, too late, you've put it in upside-down.
Yeah, yeah - it's just a few screws to set it right, but still. Anyway, there you are: $1.50 for your new switch, 15 minutes, you're done.
Is that really all there is to it?
Yup. When we moved to our current house in 1999, Sweetie made me take a half-hour to show her how to replace outlets and switches. When I came back from work the next day, she'd rewired the kitchen! It really isn't hard, you just need to give attention to a few details here and there, and be careful not to work on energized circuits.
What was that about two different hots...?
Most of your household circuits in North America are 120 volts, alternating current. The alternating bit is that the voltage isn't actually constant, it zips up from zero, to a peak around170v, down through zero 170 the other way (not actually negative, but expressed as such), sixty times per second. The average voltage your equipment experiences is 120v. That other hot is doing the same thing, also at sixty cycles per second - hertz, hereafter - but slightly out of step. The voltage difference between the two of them, in most residential applications, will be about 208v. If you need to run something big - like a dryer or a stove - you can use 120 and use HUGE wires, or you can use 208 and somewhat larger wires. It also has the advantage of symmetrically loading your house's supply, so you don't see a big flicker somewhere when you turn the dryer on.
Starting to get a little confusing...
Don't worry about it. That's big stuff and you probably won't need to work on it. But if you do, well, maybe you've cut your teeth on something simpler. In the meantime, I recommend you check out a book or something and do a little reading. As hobbies go, saving a few bucks around the house is a pretty good one.