Retrofit 3-way

I’m not sure exactly what parts I need. My new old house is currently wired with a switch at the bottom of the stairs that operates 2 fixtures, 4 bulbs total. There is also a switch at the top of the stairs that acts as a kind of master. I believe the switch at the bottom is an original switch, with the switch at the top adding the ability to cut the lights off at bed time. Unfortunately if you find your self upstairs when it gets dark you have to go down the stairs in the dark.

The switch box at the bottom has a set of wires nutted together unswitched and a set of load lines that are switched. At the top of the stairs is a single pair of switched wires.

I would like the switch at the bottom to be able to turn on or off the lights, and I’d like the switch at the top to do the same. Toggle switch format is desirable. Dimming would be a bonus. Battery powered is ok; house wiring is better.

Can you post a picture of the wiring in the two boxes? Also just to confirm, if the lights are switched off on the switch at the bottom of the stairs, the upper switch doesn’t do anything?

What do you mean by this? You have a 3 way setup being able to control the lights from 2 switches. If the wires are hooked up wrong on either switch, then one could become a “master” where if it’s off the other doesn’t work. This can be fixed, though not applicable with Smart switches.

All you need is a master switch and 1 aux switch. There are several manufacturers such as GE, Leviton, etc. For the master you can buy either an on/off or a dimmer. Lowes carries the GE switches and they work with SmartThings. Amazon and other etailers carry them too. I personally use GE since I got a great deal on them from Lowe’s late last year.

As mentioned pictures of each box would be helpful. You need to identify which wires are load (wire to lights) and line (wire to breaker panel). From there we can try to help though if you aren’t comfortable doing this you may want to hire an electrician.

This one is not going to be simple to figure out if you are not familiar with home wiring. Someone added a switch to a 2 ways circuit and depending on how that person did. it could be hard to figure out unless you could identify all the wires. Of course that person did it wrong that’s why you have no ability to turn the light back on with the bottom stair switch in off.
If you can also find out the line hot, neutral and load. That would be very helpful.

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I’m comfortable with a dmm and linesman pliers; I just don’t know the zwave products.

If the upper switch is on, the lower switch will turn the lights on and off. If the upper switch is off, the lower switch will not operate the lights. While the lights are installed in typical 3-way locations, they are not wired for 3-way. There is no traveler wire and the upper box does not have neutral or line. At the lower box I have a neutral, line and load. The upper box is only load. I took the boxes apart to reverse-engineer the wiring but the insulation is so old I’d rather not flex it to take a picture unless I’m installing.

One problem I’m coming across with some of the systems I’ve seen is that the wiring at the upper switch box is not live if the lower switch is not on. So I can’t use a line powered switch at the top and I think a battery powered switch at the top will be required.

You are right about a battery operated switch at the upstairs. There is no option for smart 3 ways switches unless you can pull another cable with your setup.

I bet that your new old house has a 3way setup but it’s wired incorrect… For a correct 3way setup you need 2 travelers wire between the 2 switches. It’s actually simple. Just Google 3way switch wiring. I have that setup in my kitchen and in my family room too using GE ZigBee switches

This is not just a simple fix. He only has 2 wires at the upstairs switch which is used to cut out the load. I see this quite often and depend on your house finishing. It’s a costly fix sometime.

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Navat, I could take the upper switch out of the circuit and tie the wires together and just use the box for mounting. Is there a list of the best working battery operated switches?

New/old house was built in 1940.

Here’s the list of battery-operated buttons and switches.

Most of these would work fine as long as your SmartThings hub was working because the battery operated device sends a message to the hub and the hub then sends a message to the master.

However, because this involves stairs and you really want to be able to turn the lights on even if your hub is not working, i’m going to suggest that you consider two Cooper aspire switches for your set up. A wired master at the bottom of the stairs and a battery operated aux at the top. (That’s the cooper 9500 as the battery operated device.)

These two switches can be set up to talk directly to each other using Z wave Association, although you will require one additional device, Z wave Aeotec minimote to make the association in a one time set up. The minimote itself is a very popular handheld remote and you can use it as a regular button remote independent of using it as an association tool. If you shop around you should be able to find a minimote for about $20.

Aeotec minimote

You will not need the Cooper controller, that’s for if you are not using the smart things hub.

Anyway, that way the switch at the top of the stairs will still work even if your hub is off-line. It does mean you have to buy the extra device, but I think it’s worth it in this case.

Shop around for the cooper aspire 9500 as well, but prices vary a lot on this one. And sometimes a place that has the cheapest minimote has the most expensive 9500.

Cooper 9500, battery powered “anywhere” switch

Thanks JDRoberts, I was planning on buying a minimote for my ceiling fan project. I did not even know it was possible to HA without a hub. you are suggesting I do not associate either cooper switch to the hub, right? Is it possible to associate the 2 switches to each other AND to the ST hub so I can do any kind of motion control or time based control later? Is the ability to associate directly to another zwave end node a common ability, and what might it be called in a spec sheet?

Sorry if I was confusing. No, you do both, it just gives you parallel means of control. You join each switch and the minimote to The network for which smart things is the primary controller. Then you can do all the usual smart things stuff with them as long as the hub is up. (And you can still trigger the master off a zigbee motion sensor or whatever.)

It’s just that in addition, separately you do a Z wave association between the two switches, using the minimote to affect the association. This can only be done if all three devices are part of the same network, which they will be, because they will all belong to the SmartThings controller.

What’s the association is made, the two switches are allowed to talk directly to each other without talking to the smartthings hub first. There’s a very limited set of messages they can communicate this way, but on, off, and dim are allowed. So it’s perfect for a virtual three-way set up. :sunglasses:

Association will only work between 2 z wave devices which both support “association” and which are within one hop of each other. Basically in the same room.

So most of the time we don’t use it in a SmartThings installation, because you get a lot more features if you go through the hub, including the ability to have a Z wave switch turn on A zigbee bulb, etc. and the ability to have a switch in the upstairs bedroom control lights on the front porch which you’re more than one hop away. And of course the ability to schedule and trigger events based on sensor readings and all that.

But Z wave association is still useful in certain use cases. And setting up a virtual three-way for switches on stairs is definitely one candidate. :level_slider: :bulb: :level_slider:

You can check to see if any certified Z wave device support association by checking its “conformance statement” on the official Z wave alliance site.

So you “join” or “include” to the network and " associate" one zwave device to another.

Just to keep you on your toes, some devices do get “associated” to the hub as well as “joined,” but that has to do with some specific technical issues and if it’s required, the user guide for the device will tell you to do it. In a SmartThings network, for yet other technical reasons, The Hub will sometimes sneak itself into an association group so it can listen in on what’s happening, but again, you don’t have to worry about that unless there are specific instructions for a specific device.