Problems with temperatures below -3.8 C

Hello,

I use your driver with a Temper2 and and a Raspberry Pi. It works great until the temperature goes under -3.8 C. Whatever the temperature is outside the driver will never report lower than this. I tried a second Temper2 unit with the same result. Could it be a bug in your driver?

Here is a graph to illustrate the problem.
http://i.imgur.com/MTD4G6w.jpg

 Blue Skies,
 /David
