PCB stands for Printed Circuit Board, which is a flat, thin piece of plastic that has electronic components built into it. In air conditioners, the PCB manages the power supply to the various components of the system, regulates the voltage and current supplied to each component, and communicates with the remote control and displays the devices status on the display panel. The PCB is responsible for controlling and regulating the systems various functions and is considered the brain of the air conditioner. It converts the AC voltage coming through the wall outlet into DC voltage that can be used by devices and appliances, reducing energy consumption by reducing losses in the conversion process. The PCB is equipped with diagnostic capabilities to detect and identify faults or malfunctions within the AC unit, and it can display error codes or indicators to assist technicians in troubleshooting and repairs. In summary, the PCB in AC is a vital component that serves as the central control unit of the air conditioning system, controlling and regulating the systems various functions to ensure that the device works efficiently and effectively.