Re-add Disconnected Device after Power Outage?

The other day, we had some weird power issues during a storm that caused my Honeywell Z-wave thermostat to become lost to the mesh. I’ve had this happen when turning breakers on and off on some of my Zwave switches, and normally I force delete the device in ST, toggle the switch on and off to reset it, and reinclude it. Of course, the downside is having to delete and readd the devices to every SmartApp it was apart of.

I thought I read somewhere that there was a way to make this process easier on the SmartApp side. Can anyone else chime in on how that’s done?

Do I go into the IDE while the “lost” device is still in ST and note the Device ID, change it to something random, go through the remove/reset/readd procedure and change the new Device ID back to what the old one was?

I have this happen with some Cree bulbs from time to time. I usually go into the ST app -->my home -->Things and rename it, save it, wait 5 minutes and name it back to its original name. I usually fine that I can then control it.

You’re probably thinking of the Z wave “replace” utility. This will only work with zwave devices. It’s part of the zwave standard. It was originally intended to let you replace a broken device with another of the exact same model and have the new device given the network ID of the old device so that you don’t have to change any of your smartapps or routines are other code.

It also works well for situations like you’ve described where for some reason they particular device has lost its connection and needs to be re-added.

Don’t force delete anything.

Instead, do a replace and the Device should slide right back into its old network slot.

Note that zwave can use the replace utility, but zigbee does not. The reason is that each zigbee device has a unique ID which it tells the network at the time of joining. So when the same device is added for a second time, it still has the same network ID and all the code still works.

Zwave works differently. Individual devices do not come from the factory with a network ID. Instead, the hub assigns a network ID at the time of pairing. So if you just add it the second time, the hub would give it a different network ID and your old code won’t work with it. But fortunately replace will work fine here. That’s because replace tells the hub to reuse the old network ID for the next zwave device that is added to the network. Which is exactly what you want in a situation like yours. ( normally zwave does not reuse IDs until it completely runs out of them.)

Just one of those cases where zwave is different from Zigbee. :sunglasses:

Instead of replace, could you use the Repair Z-Wave Network utility?

The replace utility and the repair utility serve two different functions.

The repair utility is mostly used when you have physically moved some devices around and they no longer have the same neighbor devices that they had previously. In that case, your messages will not be routed efficiently because individual devices do not know who their true neighbors are. So we want to “repair the network.”

When you run this utility, The hub talks to each device and tells it to check and see who its true neighbors are and to update its neighbor table. This process can take a long time, and sometimes battery operated devices are “asleep” when the hub talks to them and they may miss or delay processing the request. So you may not see the full results until the next day.

It’s very important to run the repair utility whenever you have added new zwave devices to your network, because otherwise the existing devices will not count it as a neighbor and your routing will not be as efficient.

But if you cannot access an existing device from the SmartThings mobile app but you can access other devices, it’s unlikely that a zwave repair will help unless you physically moved some devices around or added some new zwave devices so that the nonresponsive device is trying to use the wrong path. You can try the repair even if you haven’t changed device locations, but it’s more likely that you’ll just get error messages about that particular device.

Some people do always start with the repair just because you don’t have to physically do anything with any devices, so it’s really easy to run. It’s just a hub utility.

But if you know the problem is one particular device and you haven’t changed any device locations, then the replace lets you join that specific device to your network again Re-using its previous ID. This process will run much quicker than a full network repair, but it does require physically handling the device in order to put it into pairing Mode. With the replace, you would expect to see the results immediately as soon as the add is completed.

So it really just depends on the problems that you’re seeing. You can do both of these utilities without causing any harm. But the repair takes much longer before you see the actual results and it’s really intended for situations where you have changed the physical composition of your network by either adding new devices or moving devices to new locations. If you know the problem is a specific device, then replace might be more likely to help . :sunglasses:

Try setting the app to look for new devices. The do what it takes to put the lost device in pairing mode. Then wait till the next day. Sometimes works for me.

This method would work with a zigbee device, but it would cause a zwave device to be issued a new network ID. Then you would have to go through and change each individual smart app or routine to use the new ID.

My mistake I have lots of Zigbee devices do this. No Zwave. Sorry for the bad advice.

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It’s not bad advice, it just doesn’t apply in this case. You run into this a lot with SmartThings. The fact that it’s a multiprotocol platform is one of its strengths, but it also means that when troubleshooting, customers have to keep track of which devices are using which protocols even though most of the time when things are going well that will be invisible to them . :sunglasses:

besides all the other good advice - if you have to remove a device temporarily for any reason, don’t delete the smart apps associated with it. For things other than a thermostat (that you likely have more than one of) just substitute a different sensor in the smart app selection until your device is ready and then swap it all back. For a thermostat is it possible to have a virtual/simulated one? I have a ton of devices, but haven’t gone the thermostat route yet.

Where do you find the zwave replace utility?

I have this problem as well, and it also happens if I turn off a breaker. This is the easiest fix I’ve found.

  1. Go to the developer page.
  2. Open the device that’s acting up.
  3. Click “edit.”
  4. Click “update.” (You don’t have to change anything)
  5. The device now works as expected.

This has worked pretty consistently for me. I also have to do it with some of my devices (like the Nest) after a firmware update from SmartThings.

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Edit->Update immediately resolves this issue for my mainline powered devices (switches from various manufacturers). For my battery and plugged devices, this did not resolve the offline/online state as shown in the IDE and app. However, after performing an Edit->Update, the device was responsive to a command from the app and then updated its status.

I found out you just need to do a soft reboot with 3rd gen hub. Unplug the hub disconnect cable wait 2 minutes plug cable back and connect power. You will see blinking lights than everything will reconnect I hope this helps