Patent ID: 7178362

Claim:
A vapor compression system comprising: a fluid circuit circulating a refrigerant charge in a closed loop, said fluid circuit having operably disposed therein, in serial order, a compressor, a first heat exchanger, an expansion device arrangement, and a second heat exchanger; said expansion device arrangement including an inlet line, an outlet line, and a plurality of expansion devices, said inlet line disposed in said fluid circuit between said plurality of expansion devices and said first heat exchanger and conveying the entirety of the refrigerant charge at a relatively high first pressure, said outlet line disposed in said fluid circuit between said plurality of expansion devices and said second heat exchanger and conveying the entirety of the refrigerant charge at a relatively low second pressure; and wherein said plurality of expansion devices includes first, second and third expansion devices, said first and second expansion devices comprising fixed expansion devices and said third expansion device comprising a variable expansion valve, said second and third expansion devices being arranged in parallel and said first expansion device being arranged in series with said second and third expansion devices wherein a pressure drop across said third expansion device is less than the difference between the relatively high first pressure and the relatively low second pressure and wherein less than the entire refrigerant charge is circulated through said third expansion device.