# MQTT topic messages to variable

**URL:** <https://community.homey.app/t/mqtt-topic-messages-to-variable/44689>\
**Category:** Questions & Help\
**Created:** [March 15, 2021, 8:25am UTC](https://community.homey.app/t/mqtt-topic-messages-to-variable/44689 "2021-03-15T08:25:56Z")\
**Posts on this page:** 5\
**Page:** 4

<div class="post-metadata">

**Author:** ![robertklep](https://sea1.discourse-cdn.com/flex025/user_avatar/community.homey.app/robertklep/32/160628_2.png) [@robertklep](https://community.homey.app/u/robertklep)\
**Post date:** [August 2, 2022, 9:05am UTC](https://community.homey.app/t/mqtt-topic-messages-to-variable/44689/62 "2022-08-02T09:05:30Z")

</div>

```auto
{
  "dim": {
    "capability": "dim",
    "stateTopic": "itho/state",
    "setTopic": "itho/cmd",
    "valueTemplate": "round((value / 255) * 100)",
    "outputTemplate": "round((value / 100) * 255)",
    "displayName": "Dim level"
  },
  "measure_temperature": {
    "capability": "measure_temperature",
    "stateTopic": "itho/ithostatus",
    "setTopic": "",
    "valueTemplate": "$.temp",
    "outputTemplate": "",
    "displayName": "Temperature"
  },
  "measure_humidity": {
    "capability": "measure_humidity",
    "stateTopic": "itho/ithostatus",
    "setTopic": "",
    "valueTemplate": "$.hum",
    "outputTemplate": "",
    "displayName": "Humidity"
  },
  "measure_co2": {
    "capability": "measure_co2",
    "stateTopic": "itho/ithostatus",
    "setTopic": "",
    "valueTemplate": "$['CO2level (ppm)']",
    "outputTemplate": "",
    "displayName": "CO2"
  }
}

```

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<div class="post-metadata">

**Author:** ![Rick\_Delput](https://sea1.discourse-cdn.com/flex025/user_avatar/community.homey.app/rick_delput/32/56448_2.png) [@Rick\_Delput](https://community.homey.app/u/Rick_Delput)\
**Post date:** [August 2, 2022, 9:09am UTC](https://community.homey.app/t/mqtt-topic-messages-to-variable/44689/63 "2022-08-02T09:09:14Z")

</div>

thnx it’s working  
only he receives no data  
this while the itho add-on does receive data

 ![image](https://us1.discourse-cdn.com/flex025/uploads/athom/original/3X/7/3/7309c60143bcac3b54d43f60bbd580133db66a1d.png)  
 ![image](https://us1.discourse-cdn.com/flex025/uploads/athom/original/3X/e/9/e909ff1704e53b4b387cd6b28ab84f86716a88bc.png)

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<div class="post-metadata">

**Author:** ![RobvandeGoor](https://sea1.discourse-cdn.com/flex025/user_avatar/community.homey.app/robvandegoor/32/20328_2.png) [@RobvandeGoor](https://community.homey.app/u/RobvandeGoor)\
**Post date:** [August 2, 2022, 12:05pm UTC](https://community.homey.app/t/mqtt-topic-messages-to-variable/44689/64 "2022-08-02T12:05:06Z")

</div>

I think there is no CO2 sensor installed in the Itho.  
Only the Temp en Hum sensor is available. Did you install an extra add-on in the Itho for Co2?

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<div class="post-metadata">

**Author:** ![Rick\_Delput](https://sea1.discourse-cdn.com/flex025/user_avatar/community.homey.app/rick_delput/32/56448_2.png) [@Rick\_Delput](https://community.homey.app/u/Rick_Delput)\
**Post date:** [August 2, 2022, 12:35pm UTC](https://community.homey.app/t/mqtt-topic-messages-to-variable/44689/65 "2022-08-02T12:35:34Z")

</div>

no I have not added an add-on, but via the ip address of the wifi addon I do [see](https://us1.discourse-cdn.com/flex025/uploads/athom/original/3X/e/9/e909ff1704e53b4b387cd6b28ab84f86716a88bc.png) a co2 (ppmw) see photo previous post.  
The remote also has an auto function that I think extracts on co2, I thought…

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<div class="post-metadata">

**Author:** ![RobvandeGoor](https://sea1.discourse-cdn.com/flex025/user_avatar/community.homey.app/robvandegoor/32/20328_2.png) [@RobvandeGoor](https://community.homey.app/u/RobvandeGoor)\
**Post date:** [August 2, 2022, 12:43pm UTC](https://community.homey.app/t/mqtt-topic-messages-to-variable/44689/66 "2022-08-02T12:43:50Z")

</div>

I know what you mean because I use the same module for my Itho.  
If you have a Temp/Hum sensor installed on the module then there is no space to add an CO2 sensor.

The developer is working on a new sensor that includes CO2 but I think that will take some more time.  
In the mean time I have a separate Air Quality meter installed.

[Previous page](https://community.homey.app/t/mqtt-topic-messages-to-variable/44689.md?page=3)