Arduino temperature controller

/* Monitor average temperature with 1x 1% 10K thermistor,
cycle relay based on temperature set point to control compressor,
and circulating fan, display set point and current temperature */

// Set the nominal thermistor resistance, temp in C, and beta coef.
#define thermNomR 10000
#define thermNomT 25
#define beta 3950

// Set the value of the resistor connected to ground
#define gndRes 9910

// Number of samples to average and create array for iteration later
#define numSamples 10
int samples[numSamples];

// Define thermistor pin
#define thermistor A0

// Set Digital Pin Assignments
#define relay 3
#define fan 4
// #define tempUp 5
// #define tempDown 6

// Setup the controller
void setup()  {
  Serial.begin(9600);
  pinMode(relay, OUTPUT);
  pinMode(fan, OUTPUT);
  //pinMode(tempUp, INPUT);
  //pinMode(tempDown, INPUT);

  //analogReference(external);
}

// Control system programming
void loop()  {
  byte i;
  float avg;

  // Take thermistor samples with slight delay
  for (i = 0; i < numSamples; i++){
    samples[i] = analogRead(thermistor);
    delay(1000);
  }

  // Calculate average thermistor value
  avg = 0;
  for (i = 0; i < numSamples; i++){
    avg += samples[i];
  }

  avg /= numSamples;

  // Convert ADC value to resistance
  float thermistorResistance = gndRes * ((1023/avg) - 1);

  // Convert to resistance to temperature by Steinhart method
  float steinhart;
  steinhart = thermistorResistance / thermNomR;
  steinhart = log(steinhart);
  steinhart /= beta;
  steinhart += 1.0 / (thermNomT + 273.15);
  steinhart = 1.0 / steinhart;
  steinhart -= 273.15;                     // Convert to C

  float temperature = (1.8 * steinhart) + 32;  // Convert temperature to F

  delay(100);        //let sensors stabilize

  // Uncomment for testing through serial console
  /*
  Serial.print("Average value on A0 ");
  Serial.println(avg);

  float thermistorVoltage = avg * (5.0 / 1023.0);
  Serial.print("Volts: ");
  Serial.println(thermistorVoltage);

  Serial.print("Resistance: ");
  Serial.println(thermistorResistance);

  Serial.print("Temp F: ");
  Serial.println(temperature);

  Serial.print("Temp C: ");
  Serial.println(steinhart);
  */

  // Compare calculated values to set point and turn relay/fan on or off accordingly
  if (temperature < 38) {
    digitalWrite(relay, LOW);
    //digitalWrite(fan, LOW);
    i = 0;
    for (i = 0; i < 3 * numSamples; i++) {
    delay(60000);
    /*
    Serial.print("iteration :");
    Serial.println(i + 1);
    Serial.print("Temp F: ");
    Serial.println(temperature);
    */
    }
  }

  else {
    digitalWrite(relay, HIGH);
    //digitalWrite(fan, HIGH);
  }
}