I had the same question as I found my refrigerator will have some big temp swings . It will go from 40 down to 30, which concerned me. I too called the kevzara line and they were of no help. Just spit out what was in the documentation that comes with it. I wanted to know if you could tell if it had froze. No idea... just said don't let it freeze... well, duuuh, why do you think I called.
I bought a small refrigerator just for my kevzara.. it only has a 1-2 degree swing. As your food refrigerator is suppose to be below 40 and the low for kevzara is 36. It can be tricky. But with a seperate frig, no more troubles . But no one knows for sure about anything other than what you have allready read.