In the currently fierce temperatures below zero, the device seems to show his first weaknesses. If, for example, minus 17 degrees, the display jumps to minus 11 degrees, is a few hours at this level and then again shows the correct temp. (Now -19 degrees). New Energizer Lithium batteries can not solve your problem.
The next day, I put a brand-new unit of the same, which I really wanted to give, and to have the same problems as with the primary FR. Even at minus 15 degrees, the display jumps to minus 9 degrees. Seemingly always be the jumps 6 degrees Celsius.
Since the same error in two identical devices occurs, I go from a design flaw, or material mistake of!