LTC2631 DAC microcontroller using I2C

Having trouble understanding how this DAC functions. I'm not even sure if my Result conversion is correct, but overall code is working nonetheless. Can someone help explain?

Output on Sketch monitor: 510
Also checked the Vout pin with a voltmeter: 2.3V (so i think I understand where the 510 comes from)

But what if wanted 5V (1023 on sketch). Is that even possible?

//Include the Wire Library
#include <Wire.h>
//Set up the address of the D-A sensor
#define ADDRESS 0x73

byte da_MSB;
byte da_LSB;
int Result;

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

void loop()
{
  //Send a Request
  //Start Talking
  Wire.beginTransmission(ADDRESS);
  //Ask for Register one
  Wire.write(1);
  //Complete Transmission
  Wire.endTransmission();
  //Request 2 byte
  Wire.requestFrom(ADDRESS, 2);
  //wait for a response
  while(Wire.available() == 1); //same as register one
  
  da_MSB = Wire.read();
  da_LSB = Wire.read();
  Result = (da_MSB)+da_LSB;
 
  
   Serial.println(Result);
         
  //delay, then loop
  delay(500);
}

Try this:

  Result = (da_MSB<<8)+da_LSB;

fungus:
Try this:

  Result = (da_MSB<<8)+da_LSB;

The Sketch Monitor displays -1.