An issue with the existing thermostat capability is how does it communicate that
if the device has a fan. There are fanMode settings, but none communicate there is no fan
does the fan support the fan mode settings? Should there be an fanOff ?
If the thermostat only controls heat or cooling (but not both)?
I’ve seen these issues first hand with Nest. I’m sure other thermostats have it depending on how deployed.
At runtime we know the above, the both the capabilities, and the dth does not let us dynamically adjust the capabilities.