 void readTemperature() {
     sensors.requestTemperatures();
     temperature = (double)sensors.getTempFByIndex(0);
+    logData("temp", temperature);
 }
 
 /**

    // setup temperature sensors
    sensors.begin();
    targetTemp = TEMP_TARGET;
    // setup heater relay
    pinMode(PIN_RELAY, OUTPUT);
    digitalWrite(PIN_RELAY, relay_status);
}

        if (relay_status != LOW) {
            relay_status = LOW;
            digitalWrite(PIN_RELAY, relay_status);
            logData("relay", "on");
        }
    } else {
        if (temperature < targetTemp-TEMP_OFFSET) {
            if (relay_status != HIGH) {
                relay_status = HIGH;
                digitalWrite(PIN_RELAY, relay_status);
                logData("relay", "off");
            }
        }
    }
