I agree with PaulS, is more easy if you create a functions to open and close the window, and replace the "while for a "if", i did a similar project but instead of temperature it was light
Here the code i that i used, i guess it can be easy modified to work with temperature, and controlling a servo
// Pins
int sensorPin = 0;
int lightPin = 3;
// Variables
int lightState = 0;
int lowThreshold = 250;
int highTreshold = 35;
void setup() {
// Start Serial & set pin to output
Serial.begin(9600);
pinMode(lightPin,OUTPUT);
}
void loop() {
// Read the sensor pin
int sensorValue = analogRead(sensorPin);
// If light level is low is detected, switch light on
if (sensorValue < lowThreshold){
digitalWrite(lightPin, HIGH);
}
// If light level goes up again, switch the lights off
if (sensorValue > highTreshold){
digitalWrite(lightPin, LOW);
}
}