ActronAir Indoor PCB AMIB-P1DV 1Ph Digital is installed in the indoor unit of ESP Plus Series 2 residential split ducted systems and controls EC fan motor speed control, zone output management, and wall controller communication. When this board fails, complete loss of indoor unit operation and zone control -- replacing it with the 100% Genuine ActronAir 2020-113B restores all factory system functions without reconfiguration. Isolate power at mains before replacement -- live work on electrical components is dangerous and must only be performed by a qualified technician.