[pdeloughery]

Hello, I was looking for some clear instruction on best way to wire a connection. Please see attached drawing and picture of existing box.
What I would like to do is change out the switch on the right (single pole) and replace with a 3 way switch. I have the new 3-wire coming in to the box from the other 3 way switch (bottom right). All power is coming in from a 3-wire from the basement (bottom left). Wiring from the fixture I would like to control with the new 3 way switch comes from top right. Other wiring & 3 way (on left) controls separate set of lights.
Hoping somebody can steer me in the right directions. Thanks.
Sorry for the rudimentary drawing. id my best
Please private message me if possible.

Patrick

 

[rjniles]

Connect from the black power in to the common of the new switch (and pigtailed to the existing switch common). Connect the black from the light to the black in the 3 wire cable. Connect the white / red to the travelers of the new switch. At the far switch, connect the black to the common, connect the white / red to the travelers

 

[joed]

That drawing looks like you already have a three way switch installed on both switches.
However for a normal single pole swap out this is what you need. It comes up so often I have a word doc ready for it.

This is simple once you get three wire cable (14/3 or 12/3) to the new switch.
I am going to skip ground wires in the description. Connect all of them together and to the switch if it has a ground screw.

Remove the two wires from the existing switch. Leave everything else alone. The wires could be both black or black and white. Might even be black and red. It doesn't matter.
Connect one of the wires from the old switch to the common screw of your new three way switch#1.
Connect the other wire from the old switch to the black wire to your new switch#2 cable.
Connect the red and white wires to the remaining two traveller screws of the new switch#1.

At new switch#2 connect the black to the common screw.
Connect the red and white wires to the remaining two traveller screws of the new switch#2.

 

[rjniles]

Joed,
His existing switch is showing a ground wire and the 2 blacks are power in and power to the 3 way. Should be pigtailed.

 

[joed]

Which is the ground? The red? Does the new cable have three wires plus ground? It needs to be for a three way swap to work.

Take the two black under one screw and connect with a pigtail.

 

[Arrow3030]

You're drawing is confusing to me. The right switch appears to have a black and red wire attached to it which is either a dead short or the black and red wires are series parallel. Or I might be missing something descriptive.
Running only a xx/3 cable to the other switch location is rarely code compliant in residential anymore as switch box's, excluding some exception, require a neutral. I believe the term is a "dead end 3-way" meaning the switch box has no use beyond the 3-way.

 

[pdeloughery]

Power is coming in from bottom left. At times both black and red are hot. Black travels from single pole on right & out to a light fixture but also jumps to 3 way on left. Red also travels to back of single pole. I have attached another picture from a different angle.

 

[pdeloughery]

Hi all, once hoping to get confirmation that one of the proposed methods (mentioned earlier) would work after I added the extra picture in case there was confusion. Thanks.

 

[joed]

Still looks to me like both switches are already three ways?

 

[pdeloughery]

Switch on right is not a three way, at least not a conventional 3 way. Previous owner placed red wire into slot in back of switch.
Sorry -the pcitures keep rotating.

 

[pdeloughery]

Willing to take this offline too if that is easiest. Appreciate all the feedback so far.

 

[joed]

The instructions I gave in post #3 still hold.
The two wires you are dealing with are
1. The two looped blacks. Cut them and make a pigtail.
2. The red and black on the other screw. Pigtail them as well. It appears you have two switched items here; one on the black wire and one on the red wire.

 

[pdeloughery]

Still confused. Hoping you can go into more detail.
But yes, I have lights on left switch and different lights in right switch.
Black coming from red wire nut goes to bottom screw, loops and then on to other switch (not looking to change out this, is a 3-way). What am I doing here? Should this now only go to existing three way? And is the red now the power source for the new 3 way?
Black at top screw is going to light.
Red in rear slot is coming from power source.
From 3 way switch in other room I have black, red, & white.
Should I tie white into three other three white already nutted?

 

[joed]

This is the best description I can do

Remove the two black wires from the one screw of the existing switch. Connect them to the common screw of your new three way switch#1.
Connect the other black and red wire from the other screw of the old switch to the black wire of your new switch#2 cable.
Connect the red and white wires from the new cable to the remaining two traveller screws of the new switch#1.

At new switch#2 connect the black to the common screw.
Connect the red and white wires to the remaining two traveller screws of the new switch#2.