An air conditioner comprising: - an air conditioner body; and - a remote controller for controlling the operation of the air conditioner body, wherein - the air conditioner body includes -- a body receiver for receiving a control signal for controlling the operation from the remote controller, and -- a body transmitter for transmitting operation information for the air conditioner body to the remote controller, and - the remote controller includes -- a remote-controller transmitter for transmitting a control signal for controlling the operation to the air conditioner body, -- a remote-controller receiver for receiving the operation information transmitted from the air conditioner body, and -- a power-saving standby unit for setting the remote-controller receiver as a reception standby state when a request signal to request operation information is transmitted from the remote controller to the air conditioner body at each predetermined time interval for a given time based on either one of the request signal or the control signal, and for releasing the reception standby state after a given time has passed, the air conditioner further comprising: - the body transmitter fulfilling a function of transmitting an instruction from the air conditioner body to the remote controller for setting a reception standby state after a predetermined set period of time has passed when the remote controller is not in the reception standby state already, and - the remote controller fulfilling a function of setting the remote-controller receiver of the remote controller to the reception standby state after the predetermined set period of time, when communication is performed at the time of sending the instruction from the air conditioner body to the remote controller so that the remote-controller receiver is in the reception standby state, wherein, - the remote controller further includes -- a reception-time limiting unit for setting the remote-controller receiver as a reception standby state when the control signal is transmitted from the remote-controller transmitter, and for releasing the reception standby state after a given time has passed. - an air conditioner body; and - a remote controller for controlling the operation of the air conditioner body, wherein - the air conditioner body includes -- a body receiver for receiving a control signal for controlling the operation from the remote controller, and -- a body transmitter for transmitting operation information for the air conditioner body to the remote controller, and -- a body receiver for receiving a control signal for controlling the operation from the remote controller, and -- a body transmitter for transmitting operation information for the air conditioner body to the remote controller, and - the remote controller includes -- a remote-controller transmitter for transmitting a control signal for controlling the operation to the air conditioner body, -- a remote-controller receiver for receiving the operation information transmitted from the air conditioner body, and -- a power-saving standby unit for setting the remote-controller receiver as a reception standby state when a request signal to request operation information is transmitted from the remote controller to the air conditioner body at each predetermined time interval for a given time based on either one of the request signal or the control signal, and for releasing the reception standby state after a given time has passed, -- a remote-controller transmitter for transmitting a control signal for controlling the operation to the air conditioner body, -- a remote-controller receiver for receiving the operation information transmitted from the air conditioner body, and -- a power-saving standby unit for setting the remote-controller receiver as a reception standby state when a request signal to request operation information is transmitted from the remote controller to the air conditioner body at each predetermined time interval for a given time based on either one of the request signal or the control signal, and for releasing the reception standby state after a given time has passed, - the body transmitter fulfilling a function of transmitting an instruction from the air conditioner body to the remote controller for setting a reception standby state after a predetermined set period of time has passed when the remote controller is not in the reception standby state already, and - the remote controller fulfilling a function of setting the remote-controller receiver of the remote controller to the reception standby state after the predetermined set period of time, when communication is performed at the time of sending the instruction from the air conditioner body to the remote controller so that the remote-controller receiver is in the reception standby state, wherein, - the remote controller further includes -- a reception-time limiting unit for setting the remote-controller receiver as a reception standby state when the control signal is transmitted from the remote-controller transmitter, and for releasing the reception standby state after a given time has passed.