Patent ID: 7654109

Claim:
A refrigerating system comprising: a main refrigerant loop and an economizing refrigerant circuit; said main refrigerant loop having an evaporator, a suction line, a compressor unit with an economizer inlet, a condenser unit, a main liquid line, and said economizing refrigerant circuit; said main liquid line having a liquid receiver, an economizing heat exchanger, and a main expansion device; said economizing refrigerant circuit having an economizing liquid line with an economizing expansion device and an economizing heat exchanger; said economizing heat exchanger having a high-pressure side and a low-pressure side; the high-pressure side being associated with said main refrigerant loop and said low-pressure side being associated with said economizing refrigerant circuit; said condenser unit having a vapor inlet, a plurality of refrigerant channels, an intermediate liquid outlet, a liquid outlet, a first condensation stage associated with part of said refrigerant channels and with said intermediate liquid outlet, a second condensation stage associated with another part of said refrigerant channels and with said liquid outlet; said main liquid line being adapted for conducting the flow of liquid refrigerant from said first condensation stage to said evaporator; said economizing liquid line being adapted for conducting the flow of liquid refrigerant from said second condensation stage to said economizer inlet; said first condensation stage being so sized to provide a liquid mass flow rate required to satisfy a requirement of said evaporator to generate a required capacity and said second condensation stage being so sized as to provide a mass flow rate so as to satisfy a requirement of said economizing line.