An enbloc air conditioner has a condenser unit and an evaporator unit aligned one behind the other on opposite sides of a plane transverse to the air flow path. The walled cavity is molded onto the host portion of the plastic unit and has a low mass, which precludes the formation of sink marks and holes on the plastic unit. Upon receipt at the receiving side, the sequence number is extracted from the payload and used to synchronize the receiving side to the transmitting side. The filters may be generally constructed based on a speech recognition system.