| 摘要 |
<p>In an air conditioning system, an outdoor unit has a third communication circuit that is connected to an indoor unit having at least one of first and second communication circuits to communicate with one of the first and second communication circuits, a switch for setting connection or disconnection between one of communication terminals of the third communication circuit and one of power supply lines, and a judging circuit for setting the switch to one of a connection state that the one communication terminal is connected to the one power supply line and a disconnection state that the one communication terminal is disconnected from the one power supply line, transmitting a predetermined signal to the indoor unit under each of the connection state and the disconnection state and judging, on the basis of the presence or absence of an acknowledge signal to the predetermined signal, which one of the first and second communication circuits is connected to the outdoor unit.</p> |
