Performance enhancement of vapor compression system

In an air conditioning system comprising a compressor, a condenser, and an evaporator, the process comprising the steps of:

• feeding discharged refrigerant from said compressor to said condenser so as to provide a condensed refrigerant flow;
• splitting said condensed refrigerant flow into a main flow and an auxiliary flow wherein said auxiliary flow comprises between about 8 and about 12% wt. of total mass flow rate of said condensed refrigerant flow;
• reducing temperature and pressure of said auxiliary flow so as to provide an economizer flow;
• passing said economizer flow and said main flow through a heat exchanger so as to provide a sub-cooled main flow and an economizer discharge flow;
• feeding said economizer discharge flow to said compressor;
• and
• feeding said sub-cooled main flow through said evaporator to said compressor, wherein said economizer flow is provided at a pressure between about 5 and about 20% less than X, wherein X is defined as follows:
• X={square root over (PS)}PD,
• wherein
• PS is suction pressure, and
• PD is discharge pressure.

In a multiple circuit air conditioning system comprising at least two circuits each including a compressor, the process comprising the steps of:

• operating each compressor of said at least two circuits so as to produce at least two discharged refrigerant flows;
• feeding said at least two discharged refrigerant flows to condensing means for producing at least two condensed refrigerant flows;
• splitting a condensed refrigerant flow from at least one circuit of said circuits to obtain an auxiliary flow and at least two main condensed refrigerant flows;
• reducing temperature and pressure of said auxiliary flow so as to provide an economizer flow;
• passing said economizer flow and said at least two main condensed refrigerant flows through a heat exchanger so as to provide at least two sub-cooled main flows and an economizer discharge flow;
• feeding said economizer discharge flow to said compressor of said at least one circuit;
• and
• feeding said at least two sub-cooled main flows through evaporator means to said compressor of said at least two circuits.