What does DUAL mean on car air conditioning?

[RyderLynn]

The DUAL button on a car's air conditioning system is the dual-zone control switch. Pressing the DUAL button allows independent temperature adjustment for either the driver's seat or the front passenger seat. In vehicles, DUAL and AUTO are often displayed together. AUTO stands for automatic air conditioning. When activated, the system automatically adjusts temperature and airflow based on weather and driving conditions without requiring manual input. DUAL indicates dual-zone functionality, enabling both the driver and front passenger to individually control air conditioning temperature and airflow according to personal preferences. Functions of car air conditioning: Achieves cooling effect through continuous refrigerant circulation; Removes dust, odors, smoke, and toxic gases from cabin air to improve air quality; Humidifies cabin air to increase relative humidity. Car AC maintenance methods: Avoid setting temperature too low; Adjust vent direction properly; Avoid prolonged continuous use; Periodically use high fan speed; Turn off AC during low-speed driving.