PURPOSE: To relax limitation of the installation place of a combination refrigera tor composed of a plurality of refrigerators, to reduce the generation of a start ing current and noise during a starting, and to simplify operation.

CONSTITUTION: A refrigerator 1 is provided with a cord 3 for a commercial source, a plug socket for a commercial source, and a control panel 6 for refrigerators 1 and 2, and a refrigerator 2 is also provided with the cord 4 for a commercial source and the plug socket for a commercial source. An input/output data line 5 is connected between the refrigerators 1 and 2. Further, a cooling operation control device is incorporated in each of the refrigerators 1 and 2. The cord 4 for a commercial source is inserted in the plug socket for a commercial source of the refrigerator 1, and the cord 3 for a commercial source is inserted in an indoor insertion plug socket 7. This constitution brings the refrigerators 1 and 2 into a state to be interconnected in parallel. The cooling operation control device monitors the operation states of the refrigerators 1 and 2 by means of data through the input/output data line 5 and prohibits the refrigerators from a simultaneous starting.