Vertiv Launches New CoolLoop RDHx Back Door Cooling Solution for High Density AI Computing Scenarios
As a global leader in critical digital infrastructure and continuity solutions, Vertiv has launched Vertiv™ CoolLoop RDHx chilled water rear door cooling worldwide. Designed for AI and high performance computing workloads, it delivers efficient rack-level cooling and works seamlessly with cold plate liquid cooling. As a robust data center liquid cooling solution, it greatly improves overall heat dissipation performance.
A new member of the Vertiv™ Liebert® DCD product lineup, CoolLoop RDHx offers up to 80kW cooling capacity per cabinet. Built around proximal heat exchange, air-liquid integration, legacy compatibility and intelligent control, it facilitates data center liquid cooling renovation and enables smooth upgrades from air cooling to hybrid and full liquid cooling.
This bolt-on rear door unit requires no extra space and fits standard cabinets in common sizes. Its four-layer structure ensures reliable operation. The microchannel fin exchanger maximizes heat exchange area, while closed hot aisle design eliminates duct losses. Integrated valves, EC fans and sensors support independent closed-loop control, and quick connectors enable plug-and-play use and online maintenance.
The system adopts a two-stage air-liquid hybrid circulation. Chilled water between 12℃ and 18℃ flows from chillers or CDUs to the RDHx, forming a closed cabinet air loop. Proximal heat exchange cuts air resistance and fan power while maintaining precise temperature control.
It supports integrated operation with direct-to-chip cooling. Cold plates handle high heat flux on CPUs and GPUs, and RDHx takes away cabinet-level residual heat. The combined system handles loads from 45kW to 120kW and serves as an advanced low PUE data center solution with PUE below 1.2.
Ideal for legacy facility upgrades, the product simply replaces existing rear doors without major construction. It connects to current chilled water systems or Vertiv CoolChip CDU for secondary temperature regulation, supporting phased cooling upgrades. It fits well in standard computer rooms and modular container data center liquid cooling deployments.
Powered by six innovative technologies, the microchannel exchanger raises cooling efficiency by over 40% and reduces air resistance by 30%. Precision flow channels keep temperature variation within ±0.5℃. Running at 15℃ inlet and 21℃ outlet, it boosts chiller performance and extends free cooling time, forming a reliable energy saving liquid cooling system.
Two operating modes suit different load conditions. The passive mode uses only server fans with zero extra power for loads up to 40kW. The active EC fan mode consumes 70% less energy than traditional fans and supports full 80kW output. Fan speed adjusts dynamically based on temperature and pressure for on-demand cooling.
Pressure-independent flow valves maintain steady water flow and ±1℃ temperature accuracy against hydraulic fluctuations. Dew point monitoring prevents condensation in humid environments, and optional dual-circuit redundancy ensures non-stop operation with automatic failover.
Paired with Vertiv CoolChip CDU, the system coordinates cooling between cold plates and rear doors. It prioritizes chip-level heat removal and handles overall cabinet heat, lifting single cabinet power density from 45kW under full air cooling to 120kW in hybrid mode.
The intelligent control system delivers 200ms high-precision sampling and fast response. It centrally manages more than 32 cabinets to optimize overall energy efficiency. Digital twin technology supports real-time simulation, fault alerts and energy analysis. Covering rack level liquid cooling and row level liquid cooling, it realizes full-range intelligent thermal management.
Modular components allow easy maintenance. Full installation on one cabinet takes less than one hour with bolt-on design and quick connectors. Key parts support hot-swap replacement without interrupting IT services.
Compared with conventional rear door coolers and air conditioning systems, Vertiv CoolLoop RDHx achieves comprehensive upgrades. It delivers higher cooling capacity, dual operating modes and stable constant flow control. Native compatibility with cold plates, zero infrastructure work, low PUE and non-stop maintenance make it far more efficient and flexible.
Acting as a plug-and-play upgrade solution for AI and HPC high-density scenarios, RDHx brings remarkable industry value. It doubles cabinet computing density and reduces air conditioning power use by over 50%. Upgrades need no extra construction, with an ROI cycle of 2 to 3 years. It offers a clear upgrade path from air cooling to hybrid and full liquid cooling, maximizing existing asset value for sustainable high-density computing.
Recognized globally as a world-class liquid cooling authority, EXTRCOOL creates fully customized solutions engineered specifically for high-density AI and HPC data centers. Our complete range of premium thermal management hardware includes dual-mode CDUs, various manifold assemblies, cold plates, rear-door heat exchangers, dry coolers, and integrated containerized cooling units. These field-proven systems ensure stable performance, extensive interoperability, and straightforward scalability — enabling a seamless one-stop full liquid cooling deployment. With deep professional expertise, we serve data center operators and enterprise clients across Eastern Europe, the Middle East, South America, Southeast Asia, Central Africa, and other strategic global markets.
