Lenovo ThinkSystem Heavy Duty Full Depth 42U Rack Cabinet User Manual page 10

Rear Door Heat eXchanger V2 specifications
Dimension
Weight
Air movement
Air temperature drop
Water
For setup and installation, see "Set up Rear Door Heat eXchanger V2" on page 39.
Heat exchanger performance
Expected performance of the heat exchanger is illustrated in the following figure for a typical inlet air
temperature of 27°C (80.6°F), with a fully populated rack, near uniform power dissipation, and a 30-40 kW
heat load. By selecting the correct water inlet temperature and water flow rate, you can achieve the
necessary heat removal. A heat removal of 100% indicates that an amount of heat equivalent to that
generated by the devices has been removed by the heat exchanger and the average air temperature leaving
the heat exchanger is identical to that entering the rack (27°C /80.6°F in this example). Heat removal in
excess of 100% indicates that the heat exchanger not only removed all of the heat generated by the devices
but further cooled the air so that the average air temperature leaving the rack is actually lower than that
entering the rack.
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ThinkSystem Heavy Duty Full Depth 42U Rack Cabinet User Guide
• Depth: 129 mm / 5.0 inches
• Height: : 1950 mm / 76.8 inch
• Width: 600 mm / 23.6 inch
Empty: 39 kg / 121 lbs
Provided by servers and other devices in the rack
With high-heat-load devices, up to 25°C (45°F) between the air exiting the rack devices
and the air exiting the heat exchanger.
• Source
User-supplied, compliant with specifications in this document
• Pressure
– Normal operation: <137.93 kPa (20 psi)
– Maximum: 689.66 kPa (100 psi)
• Volume
Approximately 9 liters (2.4 gallons)
• Temperature
– Above dew point
– 18°C ±1°C (64.4°F ±1.8°F) for ASHRAE Class 1 Environment
– 22°C ±1°C (71.6°F ±1.8°F) for ASHRAE Class 2 Environment
Note: See "Heat exchanger performance" for more information.
• Required water flow rate (as measured at the supply entrance to the heat exchanger)
– Minimum: 22.7 liters (6 gallons) per minute
– Maximum: 56.8 liters (15 gallons) per minute