CoconutPete

Looking for options as far as adding an outlet behind my TV.

There is an outlet lower down on the wall where the TV is.
There are currently 6 outlets on this circuit
Wiring is BX with grounding straps in the metal boxes.
The outlet in question is in the middle of a circuit so I have 2 sets of wires there already.

What do you think? Is it too much to squeeze 3 sets AND a receptacle into that metal box? Is it even a good idea? Is it even allowed to bring new 12/3 into a box like that?

Thank You

Wuzzat?

This is the purpose of Box Fill calculations and the interpretation of these rules is sometimes tricky.

CallMeVilla

A picture would really help! The size of the box helps determine the number of wires it can handle due to heat and stress. The number of devices on the circuit will limit the receptacles.

How many receptacles are in that box now? Example: a double gang would have two receptacles with four "plug in" locations.

What is the breaker on that circuit? 15A, 20A or thermonuclear?

More info would really help ...

CoconutPete

This outlet is in my guestroom, but it's the same single gang box with one coming in and one going out as well as the outlet, so 3 sets of wires total in the box.

nealtw

Hows your math skills?
http://www.hubbellcatalog.com/raco/RACO_boxes.asp?FAM=R..

Wuzzat?

Your area may use one of these editions of the NEC
https://law.resource.org/pub/us/code/ibr/nfpa.nec.2011.html
http://freenec.com/T1.html

From the look of your wiring your house is very old. The insulation may crumble off in your hands and the conductors may be brittle.

CallMeVilla

If this was my house, I would remove the box and install a new double gang if the circuit can support it. It is worth doing and the wall repair isn't that big a deal. Can you provide the wiring layout?

CoconutPete

I think I've arrived at a different decision.

I have to refinish a piece of the floor in the spring anyway. When I'm doing that I plan on chopping the wires and pulling them both into the basement and putting them together in a junction box, eliminating this outlet from the circuit. Then I'll add another box 3' above this one and have my electrician put in a new circuit to just these 2 boxes. That way everything entertainment related is on its own circuit.

BridgeMan

You'd be wise to have Sparky run completely new grounded wiring all the way from the service panel to the new boxes. Possibly even consider doing so to more existing circuits, especially those that have higher draws. Or go the whole hog and replace the entire service panel with a new (200 A.) one using completely new wiring and circuit breakers, instead of those pesky fuses you're always replacing now. At least around here, most home fires are electrical-related or dirty dryer vents.

CoconutPete

That is the approach I have taken with my house. All the "high draw" stuff is getting new wiring. My kitchen has been completely rewired, the outlets that window A/C units get plugged into have brand new dedicated circuits and my bathrooms are next. I'm basically trying to get it to the point where the old bx wiring supports nothing but some lamps and a cell phone charger or two. That's what finally convinced me to just bite bullet and run a new circuit here. I need to have my electrician come by at some point anyway to run wire through the conduit I laid going to my garage. I like electric stuff but i know where my limits are.