I was asked to post my email discussion with HestiaPi here. I will then continue it in a subsequent post.
What happens to the HestiaPi Touch when the power goes out for up to 2 weeks and then comes back on? Does it save all its custom user-programmed parameters and last operating state in non-volatile memory (for some maximum period of time), and then resume all previous operation automatically without needing any attention from the user?
user-programmed parameters > YES
last operating state > NO - Imaging having heating ON and getting a power network failure but you are leaving for a 2-weeks holiday. You wouldn’t want to get the heating started while on the plane. So on reboot, everything is OFF unless you have hardcoded it to start something as default.
The PCB appears designed for a 9V battery backup, but the battery terminals are unpopulated – if I populate them myself, then will the 9V battery backup function conventionally?
Not sure where you see that. There is no battery support. Pi even Zero is not really a battery operating board when we are talking on a 24/7 operation.
I cannot find an image of the “translucent” case – is translucence achieved by applying a matte finish to a clear plastic (by molding, etching, beadblasting, etc.) or by using a “smoky” light-colored plastic? Or, is it actually “transparent” instead of “translucent”?
We use translucent plastic on a 3D printer
Can I write the mathematical algormithm of how the present and past (historical) temperature, humidity, and pressure data turn on and off the heating and cooling myself? I was planning to build my own thermostat some day so that I could do this, since I have never found a pre-built thermostat that optimizes along both dimensions of comfort and efficiency the way I believe it can and should. If your thermostat allows this then it would save me a lot of trouble.