It isn’t exactly what you used if you had that value_template set. What that does is:
- Read in the state of
zone.home - Throw it away and use the empty string instead
- Compare the empty string with the threshold value
In other words, it won’t work at all.
This is why the “how to help us help you” guidelines include items 9 and 11: if you’d pasted your automation, correctly formatted, in post 1, we would have picked up that error much sooner.