Patent ID: 8347641

Claim:
A cooling system comprising: a condensing unit having an inlet and an outlet; a coolant pump having an inlet, the coolant pump being configured to pump liquid coolant; a coolant line in fluid communication with the outlet of the condensing unit and the inlet of the coolant pump; a diverting valve located in the coolant line; and a sub-cooling unit configured to receive a portion of coolant from the coolant line through the diverting valve, the sub-cooling unit comprising: a sub-cooling expansion valve having an inlet in fluid communication with the diverting valve and an outlet; a sub-cooling heat exchanger having an inlet in fluid communication with the outlet of the sub-cooling expansion valve and an outlet, the sub-cooling heat exchanger being configured to transfer heat from coolant in the coolant line; and a sub-cooling pump having an inlet in fluid communication with the outlet of the sub-cooling heat exchanger and having an outlet in fluid communication with the inlet of the condensing unit.