Patent ID: 6938429

Claim:
A refrigerating and air-conditioning system comprising a refrigerating machine connected to a showcase by a first refrigerant flow passage to form a refrigerating apparatus, an air-conditioning apparatus for connection of an indoor equipment and an outdoor equipment by means of a second refrigerant flow passage, which forms a different refrigerant circuit from a refrigerant circuit formed by the first refrigerant flow passage, and a centralized control unit for controlling actions of the refrigerating machine and the air-conditioning apparatus, and wherein the showcase is installed in a room air-conditioned by the air-conditioning apparatus, and the centralized control unit is configured to reduce an indoor set temperature set by the air-conditioning apparatus relative to a fixed value according to a load on the showcase for operation, wherein the centralized control unit is configured to detect a loaded condition of the showcases making use of data indicative of an operating state of a compressor provided in the refrigerating machine, and wherein the centralized control unit uses an operating current and an operating frequency of the compressor provided in the refrigerating machine as data indicative of an operating state of the compressor, calculates an average operating current and an average operating frequency for the operating current and the operating frequency in a set period of time, and reduces a indoor set temperature in the air-conditioning apparatus relative to a fixed value according to the average operating current and the average operating frequency thus calculated for operation.