Patent ID: 9285129
Filing Date: 2016-03-15
CPC Classification: F24F,F24T,F25D,F28D,F28F,G05D,H05K,Y02B,Y02E

Claim Text:
1. An integrated, incremental, liquid-liquid free-cooling system accommodating varying equipment rack heat loads in a data center comprising: at least a first passive rear door heat exchanger (RDHx) coolant loop interfacing with an RDHx; at least a second free cooling source coolant loop interfacing with a free cooling source; at least a third chilled water supply (CWS) coolant loop interfacing with a CWS; at least one bypass circuit for load control in at least one of said loops; a three-way heat exchanger interconnecting said first, second, and third loops, wherein at least one of said first, second, or third loops comprise automatic filling and bleeding, wherein said three-way heat exchanger simultaneously transfers heat between said first, second, and third loops; at least a first and a second proportional three-way valve controlling flow in said loops; an interlock between said first and second proportional three-way valves; at least a first and a second variable speed pump to generate said flow in said loops; at least one coolant distribution unit (CDU) providing cooling to said RDHx configured on an electronics rack; a control unit controlling said valves; and at least one of a coolant temperature sensor and air temperature and humidity sensor providing input to said control unit, wherein flow is based on CDU temperature set point and a temperature of said free cooling source and a temperature of said chilled water supply.