Vapor Compression Cooling System With Improved Energy Efficiency Through Economization

Abstract

A cooling system has a cooling circuit that includes an evaporator disposed in a cabinet, a condenser, a compressor, a liquid/vapor separator tank and a liquid pump. The cooling circuit has a mode wherein the compressor and liquid pump are both on with the liquid pump pumping refrigerant through the evaporator with the refrigerant leaving the evaporator circulated to an inlet of the liquid/vapor separator tank and not to an inlet of the condenser. The cooling circuit also has a pumped refrigerant economizer mode wherein the liquid pump is on and the compressor is off and bypassed with the refrigerant leaving the evaporator circulated to the inlet of the condenser and not to the inlet of the liquid/vapor separator tank.

What is claimed is: 
     
         1 . A cooling system, comprising:
 a cabinet having an air inlet and an air outlet;   a cooling circuit that includes an includes an evaporator disposed in the cabinet, a condenser, a compressor, a liquid/vapor separator tank and a liquid pump;   the cooling circuit having a mode wherein the compressor and liquid pump are both on with the liquid pump pumping refrigerant through the evaporator with the refrigerant leaving the evaporator circulated to an inlet of the liquid/vapor separator tank and not to an inlet of the condenser, and the compressor compressing refrigerant circulating to an inlet of the compressor from an outlet of the liquid/vapor separator tank to raise its pressure and thus its condensing temperature with refrigerant leaving the compressor circulated to the inlet of the condenser, and a pumped refrigerant economizer mode wherein the liquid pump is on and the compressor is off and bypassed, the liquid pump pumping refrigerant in a liquid phase through the evaporator with the refrigerant leaving the evaporator circulated to the inlet of the condenser and not to the inlet of the liquid/vapor separator tank and wherein refrigerant circulates without compression of the refrigerant in its vapor phase.