 
 void setup() {
     lcd.begin(16, 2);
+    pinMode(backLight, OUTPUT);
+    digitalWrite(backLight, HIGH);
     sensors.begin();
     windowStartTime = millis();
 

double input;     // current temperature
double output;    // for PID
PID myPID(&input, &output, &setPoint, 2, 5, 1, REVERSE);
int windowSize = 5*60*1000;  // 5 minutes in ms
unsigned long windowStartTime;

// pot


// LCD init
LiquidCrystal lcd(12, 11, 5, 4, 3, 2);
int backLight = 13;

// PID relay control
#define RELAY_PIN 7
