Refrigeration circuit configured for circulating a refrigerant and comprising in the direction of flow of the refrigerant: at least one compressor ; at least one heat recovery heat exchanger ; a gas/liquid separator ; at least one gas cooler/condenser ; at least one high-pressure expansion device ; a receiver ; and at least one evaporator with at least one evaporator associated expansion device fluidly connected upstream thereof; wherein the gas/liquid separator comprises: a refrigerant inlet line fluidly connected to an outlet-side of the at least one heat recovery heat exchanger ; a gaseous phase outlet line fluidly connected to an inlet side of the at least one gas cooler/condenser ; and a liquid phase outlet line fluidly connected to the receiver ; wherein the refrigeration circuit further comprises: at least one switchable valve , which is switchable between a closed state and at least two different open states and configured for selectively opening and closing the liquid phase outlet line of the gas/liquid separator and a control unit , characterized by a liquid level sensor , which is configured for sensing the level of liquid refrigerant collected at the bottom of the gas/liquid separator ; and by the control unit being configured for controlling the at least one switchable valve based on the level of liquid refrigerant detected by the liquid level sensor . at least one compressor ; at least one heat recovery heat exchanger ; a gas/liquid separator ; at least one gas cooler/condenser ; at least one high-pressure expansion device ; a receiver ; and at least one evaporator with at least one evaporator associated expansion device fluidly connected upstream thereof; wherein the gas/liquid separator comprises: a refrigerant inlet line fluidly connected to an outlet-side of the at least one heat recovery heat exchanger ; a gaseous phase outlet line fluidly connected to an inlet side of the at least one gas cooler/condenser ; and a liquid phase outlet line fluidly connected to the receiver ; a refrigerant inlet line fluidly connected to an outlet-side of the at least one heat recovery heat exchanger ; a gaseous phase outlet line fluidly connected to an inlet side of the at least one gas cooler/condenser ; and a liquid phase outlet line fluidly connected to the receiver ; wherein the refrigeration circuit further comprises: at least one switchable valve , which is switchable between a closed state and at least two different open states and configured for selectively opening and closing the liquid phase outlet line of the gas/liquid separator and a control unit , characterized by a liquid level sensor , which is configured for sensing the level of liquid refrigerant collected at the bottom of the gas/liquid separator ; and by the control unit being configured for controlling the at least one switchable valve based on the level of liquid refrigerant detected by the liquid level sensor . at least one switchable valve , which is switchable between a closed state and at least two different open states and configured for selectively opening and closing the liquid phase outlet line of the gas/liquid separator and a control unit , characterized by a liquid level sensor , which is configured for sensing the level of liquid refrigerant collected at the bottom of the gas/liquid separator ; and by the control unit being configured for controlling the at least one switchable valve based on the level of liquid refrigerant detected by the liquid level sensor . <EOS>