ActronAir Indoor Evaporator EC Plug Fan K3G355AY4002 355mm 3-Phase is the 355mm variant of the K3G EC plug fan range for smaller-capacity commercial indoor units, providing EC variable-speed performance at the lower end of the commercial plug fan diameter range. The K3G355AY4002 designation identifies this specific motor model and its fan curve -- substituting a different 355mm EC plug fan with a different performance curve will alter the system airflow delivery and may trigger duct pressure fault codes. Isolate power at mains before replacement -- EC motors and variable drives retain dangerous residual voltages for up to 5 minutes after power isolation.