What Is In-Rack CDU?_
It isolates the IT-grade coolant loop from the facility water loop through an integrated heat exchanger and pump assembly. Flow, pressure, and temperature are managed locally so each rack can operate independently of row-level or hall-level cooling infrastructure. The unit typically sits in the lower or middle section of the rack and feeds vertical manifold pipes that reach the GPU cold plates.
Technical Details
Quick-disconnect fittings on the supply and return sides allow the CDU to be isolated without draining the entire rack loop. Sensors inside the CDU report differential pressure and flow to the rack-level controller so leaks or blockages can be flagged before commissioning. The secondary loop usually contains a water-glycol mixture chosen for corrosion inhibition and freeze protection; the primary loop remains facility chilled water.
How Leviathan Systems Works with In-Rack CDU
Field crews mount and leak-test the in-rack CDU during rack integration of liquid-cooled GPU systems, then connect it to the overhead facility headers before the final manifold-to-GPU hose terminations.
Related service
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