Abstract: When during a first action of a refrigeration system the internal cold storage temperature is held at a desired temperature by an evaporator, the refrigeration system performs a second action of increasing the cooling capacity of the evaporator to decrease the internal cold storage temperature. When during the second action the internal cold storage temperature reaches a minimum temperature Tmin, the refrigeration system stops a compressor and performs a third action. When during the third action the internal cold storage temperature reaches a maximum temperature Tmin, the refrigeration system drives the compressor and performs the first action.

Abstract: If the degree of opening of an electronic expansion valve (14) continues to remain below a specified degree of opening or if the degree of superheat of an evaporator (15) continues to remain above a predetermined degree of superheat, it is determined that the refrigerant circulation amount is in short supply in the water-cooled operation mode, and an air-cooled condenser fan (21) is tuned on.

Abstract: If the degree of opening of an electronic expansion valve (14) is kept below a specified degree of opening or if the degree of superheat of refrigerant at an evaporator (15) side is kept above a specified degree of superheat, the amount of circulating refrigerant is judged to be insufficient. Thus, the volume of an air delivered by an evaporator fan (22) is reduced.

Abstract: If the degree of opening of an electronic expansion valve (14) continues to remain below a specified degree of opening or if the degree of superheat of an evaporator (15) continues to remain above a predetermined degree of superheat, it is determined that the refrigerant circulation amount is in short supply in the water-cooled operation mode, and an air-cooled condenser fan (21) is tuned on.

Abstract: A refrigeration apparatus (10) includes: a refrigerant circuit (20) provided with a variable-opening expansion valve (13); and a valve control means (33) for controlling the opening of the expansion valve (13) by outputting to the expansion valve (13) an opening command value equal to or larger than a lower limit command value. During operation of a refrigeration cycle and in a lower-limit-controlled state in which the opening command value is equal to the lower limit command value, the valve control means (33) performs a first determination operation of determining whether the refrigerant flow through the expansion valve (13) is in an excessively large amount state or not based on a condition of refrigerant between the expansion valve (13) and the suction side of a compressor (11), and corrects the lower limit command value to a smaller value if the determination result in the first determination operation is that the refrigerant flow through the expansion valve (13) is in an excessively large amount state.

Abstract: A refrigeration apparatus (10) includes: a valve control means (33) configured to control the opening of an expansion valve (13); and opening degree detection means (32, 34) configured to perform, after a pump-down operation in which a compressor (11) is driven with the expansion valve (13) closed, an opening degree detection operation of detecting an opening degree that is an opening command value for use in changing the expansion valve (13) from a closed state to an open state, by determining whether the expansion valve (13) is open based on a change in state of low-pressure refrigerant between the expansion valve (13) and the suction side of the compressor (11), while gradually increasing the opening command value output to the expansion valve (13) with the compressor (11) deactivated. The valve control means (33) controls the expansion valve (13) using the opening degree detected in the opening degree detection operation.

Abstract: If the degree of opening of an electronic expansion valve (14) is kept below a specified degree of opening or if the degree of superheat of refrigerant at an evaporator (15) side is kept above a specified degree of superheat, the amount of circulating refrigerant is judged to be insufficient. Thus, the volume of an air delivered by an evaporator fan (22) is reduced.

Abstract: When during a first action of a refrigeration system the internal cold storage temperature is held at a desired temperature by an evaporator, the refrigeration system performs a second action of increasing the cooling capacity of the evaporator to decrease the internal cold storage temperature. When during the second action the internal cold storage temperature reaches a minimum temperature Tmin, the refrigeration system stops a compressor and performs a third action. When during the third action the internal cold storage temperature reaches a maximum temperature Tmin, the refrigeration system drives the compressor and performs the first action.