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

        if (relay_status != LOW) {
            relay_status = LOW;
            digitalWrite(PIN_RELAY, relay_status);
            logData("switch", 1);
        }
    } else {
        if (temperature < targetTemp-TEMP_OFFSET) {
            if (relay_status != HIGH) {
                relay_status = HIGH;
                digitalWrite(PIN_RELAY, relay_status);
                logData("switch", 0);
            }
        }
    }

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

/**
