Basic understanding: The air conditioner mainboard is divided into indoor mainboard and outdoor mainboard. In the variable frequency model, the internal and external boards communicate and work together. Among fixed frequency models, most are controlled by a single motherboard. Installation specifications: The surface of the motherboard should be kept dry and clean. It is strictly forbidden to accumulate water, moisture, or dust, otherwise it may cause a short circuit and damage the circuit board. Operation logic: After the air conditioner is turned on, the mainboard first performs a self-test. It checks sensor, voltage and communication status. Once there are no abnormal conditions, start the overall operating procedure. Routine maintenance: When cleaning the air conditioner, do not spray water directly to clean the motherboard area. Appropriate shielding and protection should be taken to ensure that circuits remain dry. Replace the adapter: After replacing the motherboard, you need to power on for self-test and trial operation in various modes. Only after confirming that the cooling, heating, defrosting and protection functions are normal can it be delivered for use., Manufacturer: ww1127