device airConditioner = "d1";
device roomTemperatureSensor = "d2";

loop {

    let currentTemperature = loadFromDevice(roomTemperatureSensor, "Temperature");

    if (currentTemperature > 25c) {
        setOnDevice(airConditioner, "On", true);
    } else if (currentTemperature <= 20c) {
        setOnDevice(airConditioner, "On", false);
    };

};