A system for cooling air for use with a liquid cooling fluid loop. The system includes a first refrigerant circuit with an air-cooled condenser, a second refrigerant circuit with a liquid-cooled condenser, and a free-cooling loop. A control device is provided for controlling the operation of the system between a first mode, a second mode, and a third mode. When operating in the first mode, only the free-cooling loop cooperates directly with liquid cooling fluid in the liquid cooling fluid loop to cool the liquid cooling fluid, when operating in the second mode, the second refrigerant circuit is not engaged, and when operating in the third mode, the free-cooling loop interacts with the second refrigerant circuit to reject heat of the second refrigerant circuit through the free-cooling loop.