The rear vertical BBQ smoker has been designed with two lower air vents and one chimney vent to allow for precision airflow adjustments. To increase temperature throughout cooks adjust each air vent accordingly.
Use the build in twin thermometers to keep a close eye on internal temperature. Once near target temperature start to close off vents leaving only a very slight gap for air to pass. If and when temperature starts to drop, slightly open a vent to allow more airflow and encourage charcoal ignition.