Cant obtain temperature

I am trying to obtain the current temperature from the following thermostate:
https://products.z-wavealliance.org/products/1062

After Zwave inclusion, it is assigned the following files:
device type: urn:schemas-upnp-org:device:Heater:1
device file: D_Heater1.xml
device json: D_HeaterTempNoOnOff1.json

If I execute the following code, the values, in the following picture, are returned: Dropbox - File Deleted

[code]local temperature = luup.variable_get(“urn:upnp-org:serviceId:TemperatureSensor1”,“CurrentTemperature”, 15)
luup.log(“TEMPERATURE:”)
luup.log(temperature)

local setpoint = luup.variable_get(“urn:upnp-org:serviceId:TemperatureSetpoint1”,“CurrentSetpoint”, 15)
luup.log(“SETPOINT:”)
luup.log(setpoint)

local setpointTarget = luup.variable_get(“urn:upnp-org:serviceId:TemperatureSetpoint1”,“SetpointTarget”, 15)
luup.log(“SETPOINT TARGET:”)
luup.log(setpointTarget)

local allSetpoints = luup.variable_get(“urn:upnp-org:serviceId:TemperatureSetpoint1”,“AllSetpoints”, 15)
luup.log(“ALL SETPOINTS:”)

local spHeat = luup.variable_get(“urn:upnp-org:serviceId:TemperatureSetpoint1_Heat”,“CurrentSetpoint”, 15)
luup.log(“SETPOINT HEAT:”)

local spPlainHeat = luup.variable_get(“urn:upnp-org:serviceId:TemperatureSetpoint1”,“CurrentSetpoint_Heat”, 15)
luup.log(“SETPOINT PLAIN HEAT:”)[/code]

Does anybody know, why the temperature is not reported and, instead, “null” is returned? According to the assigned device type, this field should be supported.

UPDATE: The majority of the time, the GUI only shows one widget for the device. Once, after inclusion, it showed two widgets - a seperate one for displaying the current inside temperature. The temperature was also reported in the log (was not null), after I executed the code above, so the question now is, why doesn’t it display this widget every time after inclusion? I’ve tried reincluding it a couple of times and could not get it to show that widget again. Dropbox - File Deleted

Thank you.