Auber InstrumentsDigital EGT Thermometer/Pyrometer with Analog Output

I am building an Arduino based controller for my wife's ceramic kiln. I couldn't find anything that would reliably read over 1000°C that would directly connect to the Arduino. I have this connected to a K-type thermocouple and have the 0-5 volt analog output connected to the Arduino. Using the scale function in the Arduino program it tracks the reading on the display. I haven't ran a full cycle on the kiln yet but it looks like this will work perfectly for what I need.

using for type J thermocouple. Reads accuratly at 212 F but is off by 8 degrees at 32 F. Slope and Zero functions do not allow adequate correction. all other function seem OKI but this is irrelevant if the measured value is wrong.