Why do Zigbee sensor drop off and then never connect again?

Configuration Zigbee
1

I am only just starting to use Zigbee. Currently I have four temperature sensors. These are using one of the SonOff ZigBee sticks flashed to work with HA. That seems reliable and generally the sensors work. Every few weeks though one becomes unavailable. Not the same one every time and sometimes more than one will be off.

No matter what I do the only thing that will get them going again is to delete them and re-pair them. This is fine with 4 temperature sensors but I am concerned that if I start buying more this could become a bit of a chore. I am surviving this because my wife is not in the least bit interested in temperature sensors. If this was the lights not working, it may become more perilous. Thus I am looking to understand why this happens, why the devices do not recover and whether there is something I can do about it.

The senors are the sonoff temperature sensors, and as said above the 3.0 sonoff stick connects them to the NUC that my HA runs on.

2

The three most common causes of issues with Sonoff Zigbee products are:

  1. Batteries. Many of the batteries that come with the sensors are trash, even if they don’t say their battery level is low.
  2. Weak mesh. If you don’t have enough Zigbee router devices, it will be highly likely that your sensors fall off the network.
  3. WiFi interference. Make sure your Zigbee network is on a channel that does not overlap with the frequencies of your WiFi or that of your neighbors.
2 Likes
3

Ah, that makes sense. Currently I only have the sensors and the hub.

I wasn’t aware there was an option to change the channel for ZigBee. I had not noticed the option, but then I had not specifically looked for it. I will have a look. I had not really researched the protocol and had assumed it was using a lower frequency further travelling bandwidth, sounds like its another 2.4 though.

4

Interference from USB 3.0 ports/peripherals/cables is another common issue, so recommend read and following this → Generic best practice tips on improving Zigbee network range and general stability · zigpy/zigpy Wiki · GitHub