Changed WiFi network for V3 Hub - all my devices are offline

I don’t really know where to start…

I have a v3 hub.

Now I got a new wifi box at home, and required to change wifi ssid. To move the hub to a new network is a menu element in the app, but seems like it’s greyed out for everyone. Anyone knowing what the developers have thought about here? Just flashing a non-existing feature to piss us off?

I found a step-by-step for changing wifi at Reddit. A guy claiming to be a Samsung employee. Long story short, the color signals he described didn’t match at all, and at the end the hub could be added new in my app. When it then started downloading updates, I had a bad feeling of being taken through a hard reset.

Now I have my app showing all the devices, but only the hub is online. All bulbs and sensors are marked as offline. The buttons are of some reason not, but when clicking them it’s not showing in the log in the app.

I guess I now have to go through the house, resetting all sensors and bulbs and buttons and pair them back again?

what steps did you follow?

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And what kind of sensors and devices are offline? (@jkp, my guess from the description is the new wifi gear slammed Zigbee…)

I don’t know if it’s too late for this, but you also have the option to enter the configuration of the new router, put in the new router the ssid and the keys of the old one and so you do not have to touch anything about home automation.
I did it like this, with two router changes and everything was working as it was


Replies to some different comments:

I followed these steps:

Or. I tried. The color codes didn’t really happen as described. Most likely I have ended up doing a hard reset.

Devices that are now not online, are some different ones:
IKEA Buttons
IKEA light bulbs
Smartthings Multisensor
Smartthings buttons
Osram power plug
Zigbee Sirens (Don’t remember the brand)

I struggled with connections of some devices to the new router. (Wifi, not related to smartthings.) I was recommended resetting the router and move to new SSIDs to prevent cached values making problems.

The new router itself has been online for some days as a test, and have not caused any problems to existing network.

Yes, it is too late to reconfigure the router.
If you already tried to turn off the hub for 15 minutes as said @jkp, since they are zigbee devices, you can try to pair the osram plugs again without deleting them.
Put the hub in non-secure mode, put the plug in pairing and in the app on + device and search nearby. Let’s see if they come back to match and you don’t have to redo automations.
If the plugs worked to see the others removing the battery and putting it back, this worked for me when a device went offline in firmware changes or because the repeaters were without power.

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Ok based on those devices i don’t think you hard reset anything - especially if your hub shows online.

Rather, I think your new routers WIFI 2.4 GHz channel is in conflict with your ZigBee network…

What channel is your 2.4ghz network using on the router and what ZigBee channel is your hub using (you can find that under My Hubs in the IDE)


Wifi is using channel 1 for 2.4GHz, the hub is at channel 14.

It would anyway sound strange the guy downstairs could run a wifi at the “wrong” channel, and by that kill my zigbee network?

Interesting finding: The Sonos system that is connected in my Smartthings environment can be started and stopped from the app.

Yep - that’s almost certainly it. These channels don’t directly line up. Change the wifi channel on tyour new router to something NOT 1. (I’d do 11, myself to get it as far away as you can.

For background: ZigBee and WiFi Coexistence — MetaGeek

2.4G WiFI

2.4G Wifi with Zigbee Channels Overlaid:

See how 14 sits right on top of Wifi 1? Wifi is orders of magnitude stronger than Zigbee and will obliterate any nearby signal if they’re interfering.


I will give it a try.

Just started the annoying work. This is what’s happening when resetting an IKEA button:

I tap the pairing button 4 times. Search for it in the app. The app finds it, but remember what name it had. When paired again, it’s working all fine.

Does this fit with the wifi band and zigbee band interferring?

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After you make the change - your stuff won’t come back immediately. You’ll have to help it along. COMPLETELY power down your ST hub and as many of your Zigbee devices as you can for AT LEAST 20 minutes after your Wifi channel change. This should force a Zigbee panic, and your devices will come up and start searching for the hub. With Wifi not splatting all over the signal they should be able to find the hub again and rebuild the mesh. Then after they’re all back up give it another 30-ish minutes to settle and start testing things.

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Yes. it does. Your zigbee network will be unstable until the channel overlap is fixed. May intermittently work - may not.

(and for your Sonos question - yes… Expected. Sonos uses Wifi. Your issue is Zigbee)


I tried to switch the wifi to 8, as that was the most open spot in the scan. Had the hub off for 30 minutes, then connected the power cable. Waited for an hour, and nothing came back online.

I will now switch the wifi to 11 as well, doing the same thing.

I don’t really get why this should work. When I factory reset one of the IKEA buttons, it connected without problems. Shouldn’t that one struggle with the interference as well?

Unstable and unpredictable. It’s RF interference Imagine talking through a static-y handheld radio. You’ll still hear some stuff. I can’t begin to predict how your new gear impacted the old without knowing EXACTLY where everything is in relation to each other - including walls, furniture, people.

Also - this is NOT a sportscar. It’s more of a freight train, these changes take time to move down the track. I’d most certainly try to get that AP on 11 before trying anything else though. If it’s that hosed this will be slowly be recovering for the rest of the day. My network typically took at least 2 hours to come back each time it happened when I was fighting a similar issue last year.

Good news from a timesaving step - If you did the panic thing once and your devices still haven’t reconnected yet you wont need to do that step again - they’re still searching.

I’m now planning to keep the hub disconnected for another hour. Then I will plug it in, and go to bed. let’s see what’s online tomorrow morning :slight_smile:

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An update from me:

Trying to switch the wifi to band 11. I had the hub offline for an hour, and then reconnected it. Over the night, no zigbee devices connected.

Next try: I completely switched off the wifi router. I’m not sure how the interaction between the hub and the zigbee devices will be with no internet access? At least, nothing connected.

I will soon try to connect the hub to router by cable, and then disable the 2.4Ghz network. By that, I guess the hub will have internet connection, but no wifi should be interupting.

And again: I can see the theoretical reason for all of this, but I really don’t understand how all of this can happen with the one button I re-connected manually being 100% connected. As said, you might at radio bands have interference that has random patterns. That something is working while something else is not, might be a result of randomness. But that the manually re-connected button is all good over a long time, while the other buttons are all gone over the same time? Statistically, that’s just not making sense?

Simplest explanation - because zigbee devices use each other to transfer signals. These routing paths create long trees of devices. If you knock out one of the routers midway in a path (say by overpowering it with noise) then every device downstream from that device falls off along with it. We dont know which routers are directly impacted. If you take the time to resolve and map all of your routing paths and draw them out along with a representation of where the signals are it would probably show you which routes are impacted. Each device lists last reported routing path and signal details. Then you address those routes first. By rejoining those devices (without deleting them first so they retain thier identity)

I know its frustrating. I personally dealt with that hell myself for two weeks straight. It was most frustrating when it was ‘almost’ working.