Adopting a mature circuit design, the signal transmission is stable and reliable, precisely controlling the operation of the entire unit, and improving the overall coordination and operational stability of the air conditioner. Integrated with multiple protection functions, it features overcurrent, overload, and overvoltage protection, effectively reducing the risk of faults and extending the service life of the air conditioner's core components. Highly compatible, it adapts to various indoor and outdoor unit structures, with reasonable interface layout, easy replacement and installation, reducing debugging and modification steps. Optimized circuit design lowers standby power consumption, reasonably reducing energy use, and helps save on daily electricity costs while maintaining stable operation. Air Conditioner Outdoor Main Board ， RRZK3491-3 RRZK3491-1 RRZK3491-2 RRZK3491-4 EE0014186B, Manufacturer: X PSBLTY