BNC sensor shield pH reading code

Hey,
I was wondering if it was possible to read a full range pH scale using the BNC sensor shield by practical maker. Arduino Shield List: Practical Maker BNC Sensor Shield

The current code reads from 7-14 or from 0-7. I was wondering if I could get the shield to read from 0-14 all in one. I tried using an if statement but no avail.

int ph_pin = 5;

float reading;
float millivolts;
float ph_value;

int i;

#define ARDUINO_VOLTAGE 5.0

// PH_GAIN == (4000mv / (59.2 * 7)) → 4000mv is max output and 59.2 * 7 is the maximum range (in millivolts) for the ph probe.
#define PH_GAIN 9.6525

void setup()
{
Serial.begin(9600);
}

void loop()
{
reading = 0;
for(i = 0; i < 50; i++)
{
reading += analogRead(ph_pin);
delay(10);
}
reading /= i;

millivolts = reading * ARDUINO_VOLTAGE / 1.024;

ph_value = ((millivolts / PH_GAIN) / 59.2) + 7; //

Serial.print("pH= ");
Serial.println(ph_value, 2); // 2 decimals
delay(500);
}