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JC
Adding 4-Way Switch

I want to add a 3rd switch to control my garage lights. There are currently 2 switches, wired as I've seen in several diagrams: the 1st switch comes off the panel, then that line runs from switch #1 to the light and then finally to the last switch.

Panel --> Switch #1 ---> Light ---> Switch #2.

I figured I would simply swap that current 2nd switch (which is a 3-way of course) for a 4-way and then add a 3-way on at the end of that.

Panel --> Switch #1 ---> Light ---> Switch #2 ---> Switch #3.

The problem is that the current 2nd switch is on an old wall and I can't figure out how to fish in a new line into that wall to lead to the last switch.

So... I'm wondering if there are other wiring options for adding that 3rd switch -without- having to fish into the wall.

Panel --> Switch #1 ---> Light ---> Switch #2 ---> Switch #3.

This may be a doofus question, but I'm wondering if there is a way to wire the last 3-way switch to the -light- (which is easy to fish to) and then replace that 2nd switch as I originally intended (with a 4-way)?

Can these switches be wired in parallel and work?

Otherwise, I guess my options are: a) tear out the plaster or b) run a really long wire from Switch #1 to Switch #3 and reverse everything.

I dunno if I'm making sense, but any suggestions would be appreciated.

Brad
Re: Adding 4-Way Switch

Short answer is, a 4 way can be added as long as you can get a three wire cable(assuming NM on my part) from one of the 3 way switches to the desired new location. The new location will be a 3 way. The 4 way will be located at the location from which the new cable originates- the existing 3 way.

JLMCDANIEL
Re: Adding 4-Way Switch

Because you have Panel --> Switch #1 ---> Light ---> Switch #2. the best way is to leave them as they are and add the 4 way wiring from the light to the 4 way switch. The 4 way requires 4 wires. Because of the wire count you may have to install a larger box or and additional box.

You would end up with Panel --> Switch #1 ---> Light ---> Switch #2.
---> Switch #3.
Jack

Brad
Re: Adding 4-Way Switch
JLMCDANIEL wrote:

Because you have Panel --> Switch #1 ---> Light ---> Switch #2. the best way is to leave them as they are and add the 4 way wiring from the light to the 4 way switch. The 4 way requires 4 wires. Because of the wire count you may have to install a larger box or and additional box.

You would end up with Panel --> Switch #1 ---> Light ---> Switch #2.
---> Switch #3.
Jack

If he is SURE both 3 wires go through the fixture J-box that would work, otherwise not.

JLMCDANIEL
Re: Adding 4-Way Switch
brrichter wrote:

If he is SURE both 3 wires go through the fixture J-box that would work, otherwise not.

One can only go by the OP's description of the circuit.

Jack

Brad
Re: Adding 4-Way Switch
JLMCDANIEL wrote:

One can only go by the OP's description of the circuit.

Jack

That is exactly what I am leery about.

Fencepost
Re: Adding 4-Way Switch

Based on your description of the circuit, run a 4-wire cable (12/4 w/ground if 20A circuit, or 14/4 w/ground if 15A circuit) from the light fixture to the new location and put your 4 way switch at the new location (switch #3).

In the light box there should be two "traveler" wires from switch #1 that run directly to switch #2, not connected to anything else in the light box. Take the two wires from switch #1 and connect them to two of the wires to switch #3. Connected the two other wires from switch #3 to the two traveler wires going to switch #2.

There is no need to change connections at either existing switch.

NOTE: 14/4 is also labeled as 14/2-2 (and 12/4 is 12/2-2). I recently saw that it is now available at my local Homely Despot. With the 14/2-2 there will be a plain white wire and a white wire with a stripe. Since neither of these white wires will be used as a neutral in this scenario, you must wrap them with either colored tape or colored marker to indicate that they are not neutral. This is a code requirement.

JLMCDANIEL
Re: Adding 4-Way Switch

Actually to meet current code you would need 5 wire cable to the new switch. 2 travelers from sw 1, 2 travelers to switch 2, and a neutral.

Jack

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