#include <DHT.h>

#define pinRelay 15
#define DHTPIN 2
#define DHTTYPE DHT22

DHT dht(DHTPIN, DHTTYPE);

void setup() {
  pinMode(pinRelay, OUTPUT);
  dht.begin();
}

void loop() {
  float temperature = dht.readTemperature();
  
  if (isnan(temperature)) {
    Serial.println("Failed to read from DHT sensor!");
    return;
  }

  if (temperature > 30) {
    digitalWrite(pinRelay, HIGH); // LED ON
  } else {
    digitalWrite(pinRelay, LOW); // LED OFF
  }

  delay(2000);
}