I've been for the last 3 days.
We'll see how long the CR2450 battery and Z-Wave power consumption lasts, lol.
A question I have is that it doesn't seem to register below 0 deg F.
Anyone else observe this?
According to Zooz, the operating temperature range is 5-104 °F, so that wouldn't be surprising:
https://www.support.getzooz.com/kb/article/1403-zse44-temp-humidity-xs-sensor-faqs/
Well, yes, my observations are that it actually goes no longer than 5F. As I recall the FAQ also mentions that the sensor has a temp range than 104F, which is not that high. Hmmm....maybe I'll look in that direction. Try to find that chip spec.
edit: This is the FAQ reference:
A little farther up in the FAQ says the sensor can go down to -40F.
So, maybe it's limited by firmware.
It's tracking the defrost cycles nicely.
I found this on a Homeseer forum.
And that'd wouldn't be the latest LR enabled chip.
My device settings may not be idealized for power savings though.
I lowered the freezer temperature, so that a dumb thermometer read -7F. Still 0F on the ZSE44.
It lasted a month in the freezer.
With a fresh battery, it lasted a month and a half in the fridge section (~constant 39).
Not outstanding.
So, I established that 0 was its lowest reading.
In trying to develop an analogue for the wood stove temp, I have it on a piece attached cast iron trim. I got it to 157.3. Stove could've gotten hotter though. 
edit1: Next load got it to 165.3.
