Air Processing Units manage airflow within the vehicle’s HVAC system, typically housing components like blower motors, evaporator cores, and condensate drains. These units are located within the vehicle’s dashboard or under-dash areas and deliver conditioned air to the cabin. Core components utilize multi-speed motors controlled by temperature and fan speed requests from the HVAC control module. Modern units increasingly integrate air quality sensors and electronically-controlled blend doors for precise temperature regulation. Construction often incorporates polymeric housings and sealed electrical connections for durability and moisture resistance.