Hi All, I have a ceiling mounted light with two ordinary cheap 3 way switches. If I use a Caseta 3 way dimmer switch, do I need to replace both ends or can I just replace one end? If I need to replace both ends, can I just replace one end if I use a non-dimmer?
It’s not the money, it’s that one end is in a bank of 4 switches so I would need to replace all 4 and find a 4 position wall plate.
The preferred method for Caseta switches for a three way is to use one of their pico auxiliaries. This is a battery powered device with a 10 year battery, so you don’t have to worry about any of the wiring for the auxiliary. The pico won’t show up as a device in the Smartthings app, but that doesn’t matter: its only job is to control the master. You will be able to dim from the pico as well as the Master.
That said, it is possible to use an existing dumb switch as the auxiliary with a Lutron Caseta Dimmer, but you won’t get dimming from the auxiliary, just on and off. Also, obviously, you have to be able to run a physical traveler wire from that auxiliary to the master. If your current wiring has both switch positions wired to the light fixture instead, it won’t work.
Here’s the technical manual with the instructions.
https://www.lutron.com/TechnicalDocumentLibrary/0301710_Caseta_Advanced_Instructions.pdf
For any further questions, contact Lutron support and they should be able to help you. This is all independent of the Smartthings integration.
support@lutron.com
www.lutron.com/support
Customer Assistance: 1.844.LUTRON1
Thanks @JDRoberts, especially for the advanced installation guide. The link on the Caseta website for that is broken. I just figured out which switch I need, it’s $120, wow! I may get the non-dimmer version instead. Your post was a huge help thanks.
Actually wait, I see the remote can be mounted in a wall box? Can it be mounted in a bank of four wall mounted switches?
Sure. There’s a backplate you have to get to hold it in place, but it looks fine. It takes the Same size cutout as a rocker switch. Same size as the Lutron master.
And here are the pieces:
That all looks great, I’ll do some of it that way.
It also occurs to me that I may be able to replace a 3 way switch with a 1 way switch if I cap off the wires at the other end, removing any switch. I can then place the remote over where that switch was. Correct?
Yes, that’s a common way of doing it as long as the wiring allows. 
Thanks! I’ll check that out, should be much less expensive.
