int setTemp = 15;
int lastTemp;
int temperature = 3;
int power= 3;
unsigned long time1;
unsigned long time2;

void setup() {

  Serial.begin(9600);
  Serial.println("BEGIN");
  Serial.println();

  pinMode(25, INPUT_PULLUP);
  pinMode(26, INPUT_PULLUP);

  lastTemp = temperature + 1;

}

void loop() {

  if (digitalRead(25) == LOW) {
    if (millis() > time1) {
      temperature ++;
      time1 = millis() + 200;
    }
  }

  if (digitalRead(26) == LOW) {
    if (millis() > time1) {
      temperature --;
      time1 = millis() + 200;
    }
  }


  // how often it will check the temp
  if (millis() > time2) {

    // ****** under limit - 13 C ****** //
    if (temperature < setTemp - 2) {

      if (temperature > lastTemp) {
        Serial.println("---------");
      }

      if (temperature == lastTemp) {
        Serial.println("Increase");
        power ++;
      }

      if (temperature < lastTemp) {
        Serial.println("Increase");
        power ++;
      }
      lastTemp = temperature;
    }

    // ****** above limit - 15 C ****** //
    if (temperature > setTemp) {

      if (temperature > lastTemp) {
        Serial.println("Decrease");
        power --;
      }

      if (temperature == lastTemp) {
        Serial.println("Decrease");
        power --;
      }

      if (temperature < lastTemp) {
        Serial.println("---------");
      }
      lastTemp = temperature;
    }

    // just printing
    Serial.print("Temperature: ");
    Serial.println(temperature);
    Serial.print("Power: ");
    Serial.println(power);
    Serial.println("**************************");

    time2 = millis() + 3000;
  } // millis

}