kta-259k Thermocouple multiplexer

New here and new to Arduino, I am building a gauge to display a list of data for my diesel truck and I would like some help. I chose to use the Oceancontrols KTA-259k thermocouple multiplexer due to the 8 inputs and the small proto board to connect my analog sensors. I seem to have it running ok on Cory J. Fowler’s library (took me a while to figure out to enable the multiplexer in the .h file), the only issue I have is that I get a random number returned as a signal every couple seconds. It’s usually a large number and it’s not a huge nusiance as I am only displaying on an LCD but a nice solid output would be nice. I do not think it is the thermocouple as I have tried oceancontrol’s sample sketch and it provides a solid output. Any Ideas?

Examle for MAX31855_lib library for MAX31855* thermocouple amplifier
Written by Cory J. Fowler
BSD license, all text above must be included in any redistribution.

#include <SPI.h>
#include <MAX31855.h>

const byte scale = 2; // 0 is Celsius/Centigrade, ~80µs. 1 is Kelvin, ~108µs. 2 is Fahrenheit ~100µs. 3 is Rankine, ~100µs.

byte error;
byte channel = 0;

double external;
double internal;

MAX31855 TCM(9);

void setup(){
//pinMode(10, OUTPUT);
//digitalWrite(10, HIGH);

void loop(){

TCM.setMUX(channel); // Set MUX channel, enable MUX, and start MAX31855 conversion process.
TCM.getTemp(external, internal, scale, error); // Read MAX31855

(channel = 0);{