View Full Version : Running a 20-amp circuit
Arande2
Sep 29, 2007, 11:07 AM
I am building a home theater and am now going to be requiring 2 20-amp circuits for certain amps I will be putting in.
My dad is an electrician with a master's license (a master electrician, if you will) that he has had for about 30 years. I think he'd be able to do it, but I still want to know about it. Thanks. ;)
Washington1
Sep 30, 2007, 03:45 PM
You want to know about what?
labman
Sep 30, 2007, 06:13 PM
You must have room in your breaker box for more circuits. You can always add tandem breakers, but most boxes specify a maximum number of poles, which may mean you have to add a sub panel. For a 20 amp circuit, you put in a 20 amp breaker and run # 12-2 with ground. Usually in a residence you use NM-B. It is a bit of a pain to retrofit into existing walls. You can tack up surface mount conduit instead. Finally, you install a box with the outlet. In a retrofit you can use old work boxes that clamp to the drywall and don't have to be nailed to the studs. You dad will know the details I left out.
donf
Oct 1, 2007, 11:17 AM
Also, if you are running 20A through 12/2 you must use 20A receptale in order to be code compliant. If your dad is actually a master sparky, then you should be able to have this conversation with him.
Washington1
Oct 1, 2007, 12:44 PM
Still the question remains. Yet, the two post are a start!
Lab are you an electrician?
labman
Oct 1, 2007, 12:52 PM
No I never claimed to be. I stick to what I know, which in some cases is more than some other people that sound like they are doing wiring jobs. Actually I mostly stay out of electrical questions unless I see a poor answer. It sounded like the guy wanted the basics, and I was able to give them.
Stratmando
Oct 2, 2007, 06:26 AM
If in conduit, you may be able to pull 3 new wires from panel to new location(2 hots, a 1 neutral) both hots need to be on opposite phases to share neutral, or neutral could be overheated or burned up by seeing up to 40 Amps(total to the 2, not the difference of the 2.
If you ran 12-3, you could have 2 circuits as well. Still need to be on opposite phase.
If for some reason, you want 2-20 Amp circuits on 1 duplex receptacle, break the "Hot" tab on receptacle. You would need a 2 pole breaker so it breaks both 120 volt circuits.
donf
Oct 2, 2007, 07:06 AM
Whoa, Sratman - You have just told him to wire 220/240.
OK, Can you use Retrofit boxes? The answer is Yes, that is the recommended method. Certainly, if the wires are run to the outlet, are 12/2 then you can use the existing wires. However, if the wire is #14AWG, back to a 15 Amp breaker, then NO! If you want to draw 20 Amps, then you must replace the breaker in favor of a 20 Amp breaker. The wire must be upgraded to 12/2 or 12/3 and the outlet must be changed to a 20 Amp rated outlet. This is mandated by the NEC Code. Running #14 cable carrying 20 Amp is asking for a fire.
Stratmando
Oct 2, 2007, 07:32 AM
Donf,
You may have missread, like you say use 12-3, that is 2 120 volt 20 amp circuits(multicircuit).
Don't know where the #14 wire was mentioned?
Where I live, we haven't been able to use #14 or aluminum for almost 30 years,
A supplement to the NEC. I will NEVER suggest #14 or Aluminum wire(Have seen to many problems with aluminum, from salt air and corrosion. Some areas are fine. I like Copper.
biggsie
Oct 2, 2007, 08:01 AM
If he is running conduit, single strain wires wires would pull easier than 12-3 cable
Each circuit requires a hot, neutral, and ground run from the breaker to outlet
If you pull only 3 strained wires through 1/2 inch conduit it is fairly easy
Pulling 6 stranded wires is not that difficult if properly lubricated
The biggest problem is too many bends -- help is good when pulling wires
labman
Oct 2, 2007, 08:18 AM
Good thing you have your dad to count on.
donf
Oct 2, 2007, 08:36 AM
OK - Let's restart here!
Arande2 It would be real nice if you would chime in and level set this question. Stratman, Yes, I agree with you on the use of #14 wire, however, we cannot see the wire Arande2 physically has at his location, so I asked the question.
What I believe has been stated and asked for:
1) Building a Home Theater and needs to run two 120vac/20amp outlets.
My first questions - Is this new construction or are you making over a room?
Are the outlets in the room 15 Amp outlets or 20 Amp outlets?
What is the source for these outlets 15 Amp on panel box or 20
Amp on panel box?
2) Do you require a single 20 Amp run to a 20 Amp outlet or split double outlet? Or do
You require two independent runs to two 20 Amp outlets
If the panel box for this run is 20 Amp breaker, through 12/2 cable to 20 Receptacle you are fine. However, if the Panel source is 15 Amp over #14 cable to a 15 Amp outlet, you are in trouble. To be code complaint, you must install a 20 Amp breaker, run 12/2 or 12/3 wire and install a 20 amp outlet.
The mention of #14 AWG came from me because I wanted to make sure that 12/2 or 12/3 are in the wall
tkrussell
Oct 2, 2007, 08:40 AM
The original poster asked a broad, general question, which was reponded to with a question for more detail by Washington.
No response from the original poster, but plenty of discussion about who knows what.
Poster has an electrican.
This question is closed.