Abstract: The invention relates to a refrigerant for use in a single-stage or auto cascade refrigeration system. The refrigerant comprises a mixture of gasses of at least three different hydrocarbons. The at least three different hydrocarbons include butane (C4H10), ethene (C2H4) and methane (CH4). The mixture of gasses comprises at the most 10% by weight of methane (CH4). The invention also relates to a refrigeration system with methane-containing refrigerant, to a refrigeration cabinet with methane-containing refrigerant and to use of a refrigeration cabinet with such refrigerant.

Abstract: A method for calibrating a superheat sensor (5) for a refrigeration system is provided. The method comprises the following steps. Increasing an amount of liquid refrigerant in the evaporator (1), e.g. by increasing an opening degree of the expansion valve (3). Monitoring one or more parameters, e.g. the temperature of refrigerant leaving the evaporator (1), said parameters reflecting a superheat value of the refrigerant. Allowing the value of each of the parameter(s) to decrease. When the value(s) of the monitored parameter(s) reaches a substantially constant level, defining the superheat value corresponding to the constant level to be SH=0. The superheat sensor (5) is then calibrated in accordance with the defined SH=0 level. When the parameter(s) reaches the substantially constant level it is an indication that liquid refrigerant is allowed to pass through the evaporator (1), and thereby that the superheat of the refrigerant leaving the evaporator (1) is zero.

Abstract: A superheat sensor (1) for sensing superheat of a fluid flowing in a flow channel (3) is disclosed. The sensor (1) comprises a flexible wall defining an interface between an inner cavity (5) having a charge fluid (6) arranged therein and the flow channel (3). The flexible wall is arranged in the flow channel (3) in thermal contact with the fluid flowing therein, and the flexible wall is adapted to conduct heat between the flow channel (3) and the inner cavity (5). Thereby the temperature of the charge fluid (6) adapts to the temperature of the fluid flowing in the flow channel (3), and the pressure in the inner cavity (5) is determined by this temperature. A first wall part (7, 14) and a second wall part (9, 16) are arranged at a variable distance from each other, said distance being defined by a differential pressure between the pressure of the charge fluid (6) and the pressure of the fluid flowing in the flow channel (3), i.e.

Abstract: A method for calibrating a superheat sensor (5) for a refrigeration system is provided. The method comprises the following steps. Increasing an amount of liquid refrigerant in the evaporator (1), e.g. by increasing an opening degree of the expansion valve (3). Monitoring one or more parameters, e.g. the temperature of refrigerant leaving the evaporator (1), said parameters reflecting a superheat value of the refrigerant. Allowing the value of each of the parameter(s) to decrease. When the value(s) of the monitored parameter(s) reaches a substantially constant level, defining the superheat value corresponding to the constant level to be SH=0. The superheat sensor (5) is then calibrated in accordance with the defined SH=0 level. When the parameter(s) reaches the substantially constant level it is an indication that liquid refrigerant is allowed to pass through the evaporator (1), and thereby that the superheat of the refrigerant leaving the evaporator (1) is zero.

Abstract: A superheat sensor (1) for sensing superheat of a fluid flowing in a flow channel (3) is disclosed. The sensor (1) comprises a flexible wall defining an interface between an inner cavity (5) having a charge fluid (6) arranged therein and the flow channel (3). The flexible wall is arranged in the flow channel (3) in thermal contact with the fluid flowing therein, and the flexible wall is adapted to conduct heat between the flow channel (3) and the inner cavity (5). Thereby the temperature of the charge fluid (6) adapts to the temperature of the fluid flowing in the flow channel (3), and the pressure in the inner cavity (5) is determined by this temperature. A first wall part (7, 14) and a second wall part (9, 16) are arranged at a variable distance from each other, said distance being defined by a differential pressure between the pressure of the charge fluid (6) and the pressure of the fluid flowing in the flow channel (3), i.e.