Receiver tank purge in vapor compression cooling system with pumped refrigerant economization

摘要

A cooling system includes a cooling circuit having an evaporator, a condenser, a compressor, an expansion device, a liquid pump, and a receiver/surge tank coupled between the condenser and the liquid pump. The cooling system has a direct expansion mode and a pumped refrigerant economizer mode. When the cooling system switches from the direct expansion mode to the pumped refrigerant economizer mode, refrigerant is flushed from the refrigerant/surge tank so that the cooling circuit is overcharged when it begins operating in the pumped refrigerant economizer mode.

主权项

1. A cooling system, comprising:
a cabinet having an air inlet and an air outlet and a cooling circuit that includes an evaporator disposed in the cabinet, a condenser, a compressor, an expansion device, a liquid pump, and a receiver/surge tank coupled between the condenser and the liquid pump; the cooling system having a direct expansion mode wherein the compressor is on and compresses a refrigerant in a vapor phase to raise its pressure and thus its condensing temperature and refrigerant is circulated around the cooling circuit by the compressor and a pumped refrigerant economizer mode wherein the compressor is off and the liquid pump is on and pumps the refrigerant in a liquid phase and refrigerant is circulated around the cooling circuit by the liquid pump and without compressing the refrigerant in its vapor phase; and when the cooling system switches from the direct expansion mode to the pumped refrigerant economizer mode, refrigerant is flushed from the refrigerant/surge tank so that the cooling circuit is over charged when it begins operating in the pumped refrigerant economizer mode.