Z-wave sensor switching between C and F

I have three Zooz ZSE11 Q-Sensors (motion, temperature, humidity, luminance).

One of them consistently reports the temperature in Fahrenheit.

The other two report in Celcius 95% of the time, then will occasionally switch to F, then a few minutes later back to C. E.g. from the logs:

2023-01-29 21:30:31.821 [INFO ] [openhab.event.ItemStateChangedEvent ] - Item 'motionSensorFamily_temperature' changed from 19.4 to 66.9
2023-01-29 21:32:39.395 [INFO ] [openhab.event.ItemStateChangedEvent ] - Item 'motionSensorFamily_temperature' changed from 66.9 to 19.3

There don’t appear to be any config params for setting C/F.

It seems to me that this must be happening on the hardware, but I’m not familiar enough with the Z-wave OH addon to know that for sure. Any suggestion on things I might try in OpenHAB?


According to https://www.support.getzooz.com/kb/article/1003-zse11-q-sensor-advanced-settings/ it would be parameter 18 that can be used to switch units between C and F:

Temperature Sensor

Parameter 18: Set the temperature unit for your sensor. NOTE: many home automation platforms will automatically adjust the reporting unit for you based on your general platform or device settings which will override this parameter so please make sure you check these settings as well.

Values: 1 – Celsius; 2 – Fahrenheit (default).

Size: 1 byte dec

I have the same issue with a few z-wave devices ( Honeywell T6 thermostat, Zooz ZSE44, I’ll have to look at my other temp sensors to see). It seems random and aligns with F to C but as it’s a number not sure if it is changing from f to c. I know the device setting is on F and the temp reported will flip back within a few minutes.

Parameter #18 is missing from the device definition in the Z-Wave database. The manual in the Z-Wave database doesn’t mention parameter #18.

Z-Wave JS: Z-Wave JS Config DB Browser

I call it ‘Z-Wave hell’: just another example of crappy documentation by the device manufacturer …

You could add parameter #18 (and additional parameters) to the Z-Wave database by following the instructions in the Z-Wave database guide. I doubt that adding and setting parameter #18 would fix the problem - but who knows?

Considering @Nick_Wilkinson’s information, it looks like a problem in the Z-Wave Binding and/or openHAB (UoM?).

Good find! Most of those parameters aren’t listed in the device’s documentation, which is probably why they aren’t configurable through the OH Thing config. I’ll find another way to set them manually…

I’ll give that a try; might not solve the problem of occasionally flipping formats, but if they’re 95% F instead of C, that would be an improvement. :slight_smile:

The other aspect to this is the firmware version. The zooz article is talking about firmware 1.11. I have one of these devices (firmware 1.9) and do not have the additional parameters (although I have not had the problem in this post either). So two things, if you upgrade the firmware you should have param 18, but the DB should bracket the firmware as =>1.11 and leave the current version as =<1.10, as the earlier versions do not have this parameter. The Zooz site should have the firmware upgrade (if it is possible for the version you have. Make sense?

Good point, I’ll make sure to include that.
The ZSE11 that’s reporting correctly is version 1.21, while the two problematic sensors are 1.30 (the latest from Zooz).

Product Configuration Capabilities looks identical to the data in the Z-Wave JS database (of course without reference to firmware versions …).


What makes you think that your device (firmware 1.09) doesn’t support parameter #18?

The manual and the comment about optimized temperature reporting in 1.10, but I guess I can’t be positive, without calling Zooz.

Firmware: 1.09

  • S2 Security
  • Advanced settings to adjust motion, temperature, humidity, and light reporting
  • Due to hardware changes made in the following versions, the 1.09 version cannot be updated using the later firmware files

VER. 1.10 (released 10/2021)


  • Optimized motion and temperature reporting

I suspect that all the listed setting will work in 1.09 based on the release note “Advanced settings to adjust motion, temperature, humidity, and light reporting”.

What happens if I add parameters to the device that don’t work on your version? I would assume that, if you don’t try to adjust the parameters then it won’t matter (and even if you do, they would probably just be rejected).

I’ll ask, but you are probably right. If I never delete and rescan it won’t matter anyway. Will update when I find out

Have you contacted Zooz? I’ve had issues with sensors doing similar things and I received updated firmware which helped.

I haven’t, but may once I have more data. Specifically:

  1. Whether it only happens on the two newest devices (running 1.30), or also on the older version 1.21;

  2. Whether is happens with other Z-wave devices in OpenHAB (which Nick_Wilkinson’s post above inidicates, implying that it’s a broader problem than Zooz.

Have you set the Zwave binding log level to debug? You should be able to see the incoming data. And I would shoot an email to Zooz in the meantime. They’re very nice and will help you. It’ll take a little back and forth with them anyway, so you can start in parallel with your own debug.

I’ve added the missing parameters to the database entry, so they should be available once (if) the changes are approved an a new JAR is release.

Normally I just break my own HA system, so exciting to be able to break others’, too! :smiley:

No problem :wink:

@florp - Great to see you have a lead on getting the F/C configuration parameters setup - The is how the ZSE44 works. I somehow skipped over the F/C parameter part of your post when I saw you were having a similar issue to me with the random swings.

I have confirmed on my setup this week that Zooz ZSE44 Temp Sensor and the Honeywell T6 thermostat both randomly drop from 70 F to something that looks like Celsius. I thought the Hue’s outdoor sensor was doing the same thing but it only reports in Celsius and I don’t see any swings in my data. I can’t find anything in the logs yet but I just turned on Z-Wave debug to try and catch the flip-flopping. I believe the raw Z-Wave message is in the debug to see if it is coming from the Z-Wave devices. For awareness I am running OpenHAB 3.3.0 with Unraid/Docker image. If anyone else has ideas on what I should try it would be greatly appreciated.

I also have a ZSE44 (Version 1.2) but for me like the ZSE11 have not experienced this behavior. One thing to try, if not doing already, is to add metadata to the temperature item. Even if the device starts sending degree C instead of degree F, this should be corrected. This is on top of my measurement system set to “US” in OH on startup.

Thank you Bob for the suggestion - I have updated this in my configuration and we’ll see if this resolves the ups and downs.

For the more detailed view - I have confirmed that the sensors are providing the temperature in ºC. I don’t know if it is a coincidence or not but both ºC from the sensors come after what seams like OpenHAP polling the sensor for the Temperature with the Tx of the SENSOR_MULTI_ LEVEL_GET in the logs. The ºF reporting from the sensors seem to be from the sensors sending updates to OpenHAB. Not knowing anything about the internals of the Z-Wave binding not sure where to go from here if adding the unit of measure to the item doesn’t work.

Honeywell T6 Thermostate (TH632ZW)

Event Log showing the change to/from the lower number

2023-02-05 20:38:34.623 [INFO ] [openhab.event.ItemStateChangedEvent ] - Item 'Downstairs_Temp' changed from 70 to 21
2023-02-05 20:42:46.731 [INFO ] [openhab.event.ItemStateChangedEvent ] - Item 'Downstairs_Temp' changed from 21 to 70

Z-Wave Logs showing the 20:38:34 temperature coming as ºC

Z-Wave Logs showing 20:42:46 temperature coming as ºF

ZSE44 Zooz Temperature Humidity Sensor
Event Log showing the change to/from the lower number

2023-02-05 15:40:31.080 [INFO ] [openhab.event.ItemStateChangedEvent ] - Item 'TempSensor3_Temp' changed from 70.9 to 21
2023-02-05 17:25:48.446 [INFO ] [openhab.event.ItemStateChangedEvent ] - Item 'TempSensor3_Temp' changed from 21 to 70.8

Z-Wave Logs showing both events