Abstract: In a communication device, a communicator communicates with a communication counterpart using a first communication mode or a second communication mode. When a communication by the communicator with the communication counterpart using the second communication mode is reset due to a first cause, if the communication with the communication counterpart using the second communication mode is acceptable, a communication controller causes the communicator to resume communication with the communication counterpart using the second communication mode, and if the communication with the communication counterpart using the second communication mode is unacceptable, the communication controller causes the communicator to start a communication with the communication counterpart using the first communication mode.

Abstract: A maintenance support system includes an air conditioner system including air conditioners, an Internet line, a portable terminal and a server, and supports maintenance of the system. The system, portable terminal, and server are communicably interconnected via the Internet line. The server stores individual identification information, operation information and abnormality history of each air conditioner. The portable terminal receives the individual identification information, operation information and abnormality history of each air conditioner from the server. The portable terminal includes an image pickup unit photographing a space to acquire a picked-up image thereof, and a display unit displaying the air conditioner included in the picked-up image and one of the individual identification information, the operation information and the abnormality information of the air conditioner in association with each other with one being superimposed on other.

Abstract: In a communication device, a communicator communicates with a communication counterpart using a first communication mode or a second communication mode. When a communication by the communicator with the communication counterpart using the second communication mode is reset due to a first cause, if the communication with the communication counterpart using the second communication mode is acceptable, a communication controller causes the communicator to resume communication with the communication counterpart using the second communication mode, and if the communication with the communication counterpart using the second communication mode is unacceptable, the communication controller causes the communicator to start a communication with the communication counterpart using the first communication mode.

Abstract: A maintenance support system includes an air conditioner system including air conditioners, an Internet line, a portable terminal and a server, and supports maintenance of the system. The system, portable terminal, and server are communicably interconnected via the Internet line. The server stores individual identification information, operation information and abnormality history of each air conditioner. The portable terminal receives the individual identification information, operation information and abnormality history of each air conditioner from the server. The portable terminal includes an image pickup unit photographing a space to acquire a picked-up image thereof, and a display unit displaying the air conditioner included in the picked-up image and one of the individual identification information, the operation information and the abnormality information of the air conditioner in association with each other with one being superimposed on other.