Problem with Arduino Circuit (thermometer) - arduino

Question

I have a problem with this circuit... when i Send a value from Serial Monitor in Arduino it doesn't receives the value and continues in an infinite loop. So leds don't switch on and I don't understand why.
Here below there is the image of the circuit:
This is the code:
const int sensorPin = A0;
const float baselineTemp = 20.0;
void
setup ()
{
Serial.begin (9600);
for (int pinNumber = 2; pinNumber < 5; pinNumber++)
{
pinMode (pinNumber, OUTPUT);
digitalWrite (pinNumber, LOW);
}
}
void
loop ()
{
int sensorVal = analogRead (sensorPin);
Serial.print ("Sensor Value: ");
Serial.print (sensorVal);
//converti la temperatura ADC in tensione
float voltage = (sensorVal / 1024.0) * 5.0;
Serial.print (", Volts: ");
Serial.print (voltage);
Serial.print (", degrees: ");
//converti la tensione in temperatura
float temperature = (voltage - 5) * 100;
Serial.println (temperature);
}
Leds don't switch on and serial monitor doesn't receive the values but it gives me this loop:
Thanks in advance

Answer 1

You’ll need to implement some code to turn on the leds in the loop like:
digitalWrite(pinNumber, HIGH)

Answer 2

Your question is not clear. When do you want the LED switches on?
You just read values from the serial line and print them on the serial monitor.
you have to use:
Serial.read();
to get data from the serial monitor and after that decide how the LED changes behavior. Also, you need to use
digitalWrite(pinNumber, HIGH);
to set LED pins high and then base on your condition (get some specified data from Serial or a temperature limit) turn them off by:
digitalWrite(pinNumber, LOW);