Analog Temperature sensor inaccurate? Or is the Arduino at Fault?

Other Hardware General Electronics
4 
#include <LiquidCrystal.h>
LiquidCrystal lcd(12, 11, 5, 4, 3, 2);
float tempC;                            // create variable to store the temperature in.
int tempPin = 0;                        // Attach vout to analog pin 0.

void setup()                            // Will execute once at the start of the code.
{
  Serial.begin(9600);
  lcd.begin(16, 2);
  lcd.clear();
  }

void loop()                             // code here will continue to replay until powered off.
{
  tempC = analogRead(tempPin);          // read the analog value from the lm335 sensor.
  tempC = (5.0 * tempC * 100.0)/1024.0; // convert the analog input to temperature in centigrade.
  Serial.println((byte)tempC); 
  Serial.println((byte)tempPin); // send the data to the computer.

    
  delay(3000);                          // wait 3 seconds before redoing the loop.
}

not printing to the display for now for reasons of troubleshooting. Here, i will consistently get the number 28-30, followed by a zero.
this means that tempC = 28-30, and that tempPin = 0?!?