It would be useful to have a dropdown in the device config that lets the user select a sensor device or a variable. When the value of either changes, it should be sent as the external sensor value to the TRV.
Shelly TRV supports a set of commands published on shellies/thermostat/0/command/ to address all TRVs or shellies/shellytrv-<id>/thermostat/0/command/ to address an individual device:
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ext_t accepts number to send external sensor temperature, in deg C
It would be useful to have a dropdown in the device config that lets the user select a sensor device or a variable. When the value of either changes, it should be sent as the external sensor value to the TRV.