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: A refrigeration circuit (1) sequentially connected to a compressor (10), a condenser (11), an electric expansion valve (13), an evaporator (17), and an intake proportional valve (21). When the freezing capability of the refrigeration device is to be suppressed, a control means (30) will restrict the intake proportional valve (21) in order to place refrigerant in a discharge side of the evaporator (17) in a wet saturated steam state, and the electric expansion valve (13) will be set to an aperture such that the refrigerant in the interior of the evaporator (17) will be placed in the wet saturated steam state.

Abstract: A refrigeration circuit (1) sequentially connected to a compressor (10), a condenser (11), an electric expansion valve (13), an evaporator (17), and an intake proportional valve (21). When the freezing capability of the refrigeration device is to be suppressed, a control means (30) will restrict the intake proportional valve (21) in order to place refrigerant in a discharge side of the evaporator (17) in a wet saturated steam state, and the electric expansion valve (13) will be set to an aperture such that the refrigerant in the interior of the evaporator (17) will be placed in the wet saturated steam state.

Abstract: Cooling operation is performed so as to keep a freezer at a selected temperature. Moreover, if the cooling operation enters a phase where the freezer temperature is higher than the selected temperature by a predetermined deviation or more, not only the deviation temperature but also an accumulated time obtained by accumulating the time periods during which the cooling operation is performed at the deviation temperature or higher are stored. In addition, when an instruction signal to indicate an accumulation is input, the stored accumulated time and deviation temperature are read out and indicated on a segment indicating section (7S).