I thought I'd see how it compares with the Hue motion sensor I've had in there for years.
I put in a plastic bag first, then into a freezer shelf on the side by side fridge.
It's communicating.
It doesn't do lux or motion like the Hue, which is handy for determining door status.
And, I've put it in a plastic bag, so humidity won't be meaningful, not that it would be anyway-it's not like anything can be done about it.
But, it has a display, which is nice.
A wireless display on the outside of the fridge would be nice.
Perhaps there are dumb versions that do that.
During a power outage, my hub, router, and modem would be on battery, so I guess I could see it on my phone. Needless power consumers though. Dumb might be best.
edit: I'd also get an announcement on the Ecolink chime/siren, since it's has battery backup...for a while, just like the other stuff. 
Anyway, let's see how this goes; if only as an experiment.
