See picture below. Google has been allowing the ability to select external temperature sensors for years. Ecobee has something similar. Perfect for people who have thermostats in a completely different part of their house.
I use this every night to ensure the temperature in my son’s bedroom (which is usually the coldest) is set to a more comfortable temp. Yes, this slightly raises the temp in the whole house, but better than trying to guess what temp I should raise the main thermostat temp to get a better temp upstairs.
Would love to finally be completely off the Nest app, and see HA implemented even better by allowing for usage of temp sensor templates, so I can create my own sensors to use, like “upstairs”, which would be an average of all temp sensors upstairs.
I don’t believe this would be an integration. This would be an update to the standard climate card that allows for adding 2 or more additional temperature sensors to the UI, and the selection of one of them as the set point. That way, just like the image, you can select which temp sensor you want to use from the UI.
Unfortunately everything I’ve read says that the generic thermostat integration can’t do what I’m stating. While, yes, the code can be written to use a different temp sensor as the one providing the set point, it lacks the flexibility of manually changing the sensor via the UI throughout the day. As far as I’m aware, to do so, I’d have to update the sensor used in the code for the integration everytime which doesn’t pass the WAF.
Because that would just display the other room temps. I’m trying to not just see the other temp sensors around my house, but to make one of them a set point for the thermostat.
The set point is the target temperature.
I now (think I) understand you want to be able to select the source temperature sensor at will, but your feature description is a bit confusing.
I would use a generic thermostat, with the source sensor being a template sensor that would take your son’s room sensor past a certain time, and another one otherwise.