Patent ID: 7757506

Claim:
A system for facilitating cooling of electronics, the system comprising: an electronics rack comprising at least one heat-generating electronics subsystem, the electronics rack comprising an air inlet side and an air outlet side for respectively enabling ingress and egress of external air; at least two modular cooling units (MCUs) associated with the electronics rack and configured to provide system coolant in parallel to the at least one heat-generating electronics subsystem for facilitating cooling thereof, wherein each MCU of the at least two MCUs comprises a liquid-to-liquid heat exchanger, a first coolant loop and a second coolant loop, and when operational, the first coolant loop of each MCU receives chilled coolant from a source and passes at least a portion thereof through the liquid-to-liquid heat exchanger, and the second coolant loop provides cooled system coolant to the at least one heat-generating electronics subsystem, and expels heat in the liquid-to-liquid heat exchanger from the at least one heat-generating electronics subsystem to the chilled coolant in the first coolant loop; an air-to-liquid heat exchanger associated with the electronics rack for cooling at least a portion of air passing through the electronics rack, the air-to-liquid heat exchanger being coupled to receive system coolant from the at least two MCUs and exhaust system coolant to the at least two MCUs; at least one isolation valve coupled to selectively shut off flow of system coolant through the air-to-liquid heat exchanger; and at least one controller coupled to the at least one isolation valve for automatically shutting off flow of system coolant through the air-to-liquid heat exchanger upon detection of a failure at one MCU of the at least two MCUs, wherein when operational, the at least two MCUs provide cooled system coolant in parallel to the at least one heat-generating electronics subsystem, for liquid cooling thereof, and to the air-to-liquid heat exchanger for cooling at least a portion of air passing through the electronics rack, and wherein responsive to detection of failure at one MCU of the at least two MCUs, the at least one controller employs the at least one isolation valve to automatically shut off flow of system coolant through the air-to-liquid heat exchanger, while system coolant continues to flow via at least one remaining operational MCU to the at least one heat-generating electronics subsystem for continued liquid cooling thereof.