Hello,
I have a 2-story house with the hub upstairs and a LOT of switches and dimmers (GE) that should act as repeaters both downtairs and upstairs.
I did a “repair z-wave network” twice, and that only got more devices offline.
I have a total of 45 wired devices in my house (dimmers, switches and 2 relay boxes) and 10 more battery powered (Arlo Cameras, Sonos players and door sensors).
There are some cases in which I have an offline switch that is phisically next to another that is online. There are some days where I have a switch offline and the next day it’s online.
There are other cases I have an offline switch that is closer to the hub than an online switch that is further.
I have no idea what to do. I already excluded all devices one by one and included them again. I also tried the hub downstairs. No luck there.
Any ideas? Please help
How many z-wave repairs did you perform?
I’m sure that’s very frustrating. 
First things first: Z wave repeats only for Z wave, not for zigbee or Wi-Fi devices. So your Z wave switches can’t help with devices like Arlo cameras or Sonos players. Or battery-powered zigbee sensors.
Can you be more specific about which devices are going off-line? (Brand and model)
Also, the device health feature of SmartThings has always been a little flaky and many people just turn it off. There is a distinct difference between a device actually being unavailable to the network and reporting as being unavailable. That is, it might be flagged with an ! As being unavailable but all your automations would still work and you could still turn it on and off in the mobile app. In other cases, the device is actually nonresponsive and can’t be turned on and off even from the mobile app.
So which kind of problem are you running into? Do the devices seem to be reporting into the mobile app OK but they are flagged as unavailable? Or are they actually nonfunctional?
Thanks for the reply.
They are all z-wave, not zigbee. Or at least connected to the hub as z-wave.
I have the following:
-Switches: GE Z-Wave Plus Wireless Smart Lighting Control Smart Switch, On/Off, In-Wall, Includes White & Light Almond Paddles and Zwave Repeater Range Extender, Works with Amazon Alexa (Hub Required), 14291
-Dimmers: New Model : GE Z-Wave Plus Wireless Smart Lighting Control Smart Dimmer Switch, In-Wall, Includes White & Light Almond Paddles, Works with Amazon Alexa (Hub Required), 14294
-Motion senson dimmers: GE Z-Wave Plus Wireless Smart Lighting Control Motion Dimmer, In-Wall, Occupancy Vacancy Sensor, Includes White & Light Almond Buttons, Works with Amazon Alexa (Hub Required), 26933
-2:GE Z-Wave Wireless Smart Lighting and Appliance Control, Indoor/Outdoor, Works with Amazon Alexa (Hub Required), 12726
I’m concerned about those not repeating/extending signal or if the mesh is working correctly.
Smartthings do not offer a way to tell how the z-wave network is meshing (like Google Wifi), so I can determine which are not repeating.
As of the devices going “unavailable” are usually the ones further from the hub.
Sometimes I can turn them of even though the app says “offline”, but most of the times I just can’t.
As of automatization, today I had to manually turn some lights off because the hub did not detect the devices.
A lot, more that 10 times in the past month.
The latest one I did (this morning) made more devices go offline.
Probably the best thing is to get in touch with support and let them look at it from their side. There are some things that they can see which are not visible to us as regular customers.
https://support.smartthings.com/hc/en-us
Let us know what they say.
Alvaro - I have the same issues and I am looking forward to what you find out.
The tech support folks at ST are not very tech savvy, they keep putting me on hold and asking their supervisor how to answer the question.
Please let me know if you can fix the issue. It’s very annoying!
Thanks!