AIR-CONDITIONER

PURPOSE:To reduce the current capacity available when an electric heater is arranged to an indoor machine and miniaturize the indoor machine by a method wherein a DC source circuit is arranged to an outdoor machine to receive a commercial source, and one or a plurality of the indoor machines are connected to the outdoor machine through a connection wire through which a DC source is transmitted. CONSTITUTION:A commercial source 9 is received by an outdoor machine 14 and fed to an indoor machine 13 through a connection wire 18. A DC source circuit 12 generates a DC source having a voltage lower than that of the commercial source 9, and the DC source is fed to an indoor control circuit 10 of the indoor machine 13 through a connection line 19. The indoor control circuit 10 performs control of the whole of an air-conditioner, such as control of the operation stop of a compressor 1 and control of an indoor blower 7. An outside control circuit 11 performs control of the outdoor machine 14 according to the command of the indoor control circuit 10. Communication between the indoor control circuit 10 and the outdoor control circuit 11 is carried out through the connection line 19 by means of a modulating/ demodulating circuit 17-a on the indoor machine 13 side, connected to the connection wire 19, and a modulating/demodulating circuit 17-b on the outdoor side ma-chine 14 side.