CALIBRATION METHOD OF REFRIGERANT SATURATION TEMPERATURE IN A REFRIGERATION SYSTEM, A CONTROLLER FOR APPLYING SUCH A METHOD AND A COOLING MACHINE

A method of determining a refrigerant or a composition of refrigerants in a refrigeration system comprising an expansion valve, an evaporator, one or more evaporator fans, a condenser, one or more condenser fans one or more temperature sensors, one or more pressure sensors, a compressor, and a controller for controlling the refrigeration system, the controller comprising a memory, the expansion valve, the evaporator and the compressor being fluidly interconnected in a refrigerant path having refrigerant flowing therein, comprising the steps of: a) Running a test run and read out values from one or more of the sensors; b) Determining a composition by the result of step a; and c) Adjusting the refrigeration system in relation to the composition determined by step b. Also disclosed is a controller for controlling a refrigeration system and a cooling machine in a reefer container.