Cooling system using vacuum cooling and method for operating the same, said system having a refrigerant circulation, the refrigerant circulation comprising: a vacuum chamber, a vacuum pump, a first flow of a heat exchanger of the cooling system having at least two flows, and a condensate reservoir, wherein the vacuum chamber, the vacuum pump, the first flow and the condensate reservoir are connected, wherein a refrigerant contained within the refrigerant circulation is liquid at 20 C and 101325 Pa, wherein the system further comprises a separator having an inlet connected to the condensate reservoir for receiving a gaseous phase from the condensate reservoir, an outlet connected to an inlet of the vacuum pump and an exhaust for leakage air.