A chilling unit comprising: a refrigerant circuit including a compressor configured to compress a refrigerant, an air heat exchanger configured to perform heat exchange between the refrigerant and outside air, a water heat exchanger configured to perform heat exchange between the refrigerant and water, an expansion valve provided between the air heat exchanger and the water heat exchanger, and a four-way valve configured to switch a flow path of the refrigerant to a cooling operation flow path or a heating operation flow path; a water circuit including a water pipe inserted through the water heat exchanger, a water pump configured to send the water to the water pipe, and a water valve provided closer to a downstream side of the water pipe than the water heat exchanger; and a control device configured to control the refrigerant circuit and the water circuit, characterised in that the control device includes a detecting unit configured to detect an anomaly in the water heat exchanger when a saturation temperature of the refrigerant circuit on a low-pressure side or a high-pressure side is less than a predetermined saturation temperature lower limit value, wherein the detecting unit of the control device is configured to detect an anomaly indicating refrigerant leakage in the water heat exchanger when, during a cooling operation, a saturation temperature of the refrigerant circuit on a low-pressure side is less than a first saturation temperature lower limit value, a subcooling degree at an outlet of the air heat exchanger is lower than a subcooling degree reference value, and a water temperature at an outlet of the water heat exchanger in the water circuit is equal to or greater than a lower limit value in a water temperature control range. a refrigerant circuit including a compressor configured to compress a refrigerant, an air heat exchanger configured to perform heat exchange between the refrigerant and outside air, a water heat exchanger configured to perform heat exchange between the refrigerant and water, an expansion valve provided between the air heat exchanger and the water heat exchanger, and a four-way valve configured to switch a flow path of the refrigerant to a cooling operation flow path or a heating operation flow path; a water circuit including a water pipe inserted through the water heat exchanger, a water pump configured to send the water to the water pipe, and a water valve provided closer to a downstream side of the water pipe than the water heat exchanger; and a control device configured to control the refrigerant circuit and the water circuit, characterised in that the control device includes a detecting unit configured to detect an anomaly in the water heat exchanger when a saturation temperature of the refrigerant circuit on a low-pressure side or a high-pressure side is less than a predetermined saturation temperature lower limit value, wherein the detecting unit of the control device is configured to detect an anomaly indicating refrigerant leakage in the water heat exchanger when, during a cooling operation, a saturation temperature of the refrigerant circuit on a low-pressure side is less than a first saturation temperature lower limit value, a subcooling degree at an outlet of the air heat exchanger is lower than a subcooling degree reference value, and a water temperature at an outlet of the water heat exchanger in the water circuit is equal to or greater than a lower limit value in a water temperature control range.