Coolant Distribution Units (CDUs)
Cooling interfaces for liquid cooling in data centers
Coolant Distribution Units (CDUs) form the central hydraulic interface between the primary circuit of the building cooling system and the secondary circuit of the IT liquid cooling system.
They enable precise control of temperature, pressure, and flow and are a key component of modern direct liquid cooling infrastructures for high-performance data centers.
Depending on the data center architecture, our CDU systems are available as in-row variants or in a central configuration and can be flexibly adapted to different performance requirements.
Installation concepts
CDUs can be positioned differently depending on the data center layout and cooling strategy:
- In-row designs for rack-close integration directly in the white space
- Centrally installed CDUs to supply multiple rows or entire cooling zones
Our systems thus support both compact high-performance areas and large-scale data center architectures – from individual AI (artificial intelligence) racks to complete HPC cooling clusters.
Why are CDUs necessary today?
With increasing power densities due to AI, GPU, and HPC applications, traditional air cooling is increasingly reaching its physical limits. Liquid cooling enables significantly more efficient heat dissipation directly at the source. CDUs create the conditions for a stable and controlled IT cooling cycle, independent of fluctuations in the building's water network.
CDUs in the data center
The key component as a coolant supply for high-performance IT
A coolant distribution unit is much more than just a coolant distributor. The CDU acts as an active switching and control center in the data center for direct-to-chip cooling of high-performance IT.
It ensures:
- Controlled temperatures
- Safe pressure levels
- Maximum operational reliability for AI, GPU, and HPC cooling
- Communication with BMS
Traditional air cooling –
Why it is no longer sufficient
The increasing power densities of modern AI, GPU, and HPC workloads are making air-based cooling concepts increasingly inefficient and cost-intensive. Liquid cooling in data centers is therefore becoming the standard for the economical and safe operation of high-density racks.
Direct-to-chip (D2C) cooling enables:
- Significantly higher heat densities
- Better energy efficiency
- Stable operation even with dynamic AI loads
The Coolant Distribution Unit (CDU) ensures that these cooling concepts are implemented reliably, safely, and scalably.
Your advantages with a
Coolant Distribution Unit (CDU)
A Coolant Distribution Unit (CDU) is the central interface for modern liquid cooling in data centers. It ensures maximum safety, scalability, and efficiency—especially in AI (artificial intelligence) and HPC infrastructures with high rack density.
- Hydraulic decoupling for maximum safety
The primary and secondary circuits are completely separate.
The CDU reliably protects your IT systems from pressure fluctuations, media differences, and disturbances from the building's cooling system – for stable and safe operation.
- Scalable high-density cooling for growing data centers
The in-row architecture enables the cooling capacity to be expanded step by step.
Ideal for growing AI data centers and phased expansions – without modifications to the central cooling supply.
- Precise control & intelligent monitoring
Sensors and intelligent control concepts enable reliable control and permanent monitoring of the cooling processes – a decisive advantage for critical IT environments.
- Maximum availability during operation
Redundant pumps, sensors, and components enable maintenance to be carried out largely during operation. This means your infrastructure remains available even during service calls – particularly relevant for HPC and AI applications.
- Flexible integration & sustainable future-proofing
CDUs can be flexibly integrated into new and existing data center architectures and offer options for heat recovery and sustainable cooling concepts.
Industrial precision
proven in
automotive testing
Our CDUs are based on decades of experience in automotive testing—an environment in which precise temperature, volume flow, and pressure control across a wide range of applications are absolutely essential.
We transfer this industrial expertise to data center technology:
- Robust, durable design
- Precise control
- Stable continuous operation – even with highly dynamic AI loads
Result: An industrial solution “Made in Germany”, designed for reliable operation throughout its entire life cycle.
Unique system
integration
Heat recovery
without compromise
Many CDU providers focus exclusively on the IT side. We combine hydraulics, heat transfer, and cooling and heat pump technology into a coordinated overall system – from a single source. This enables heat recovery without compromising the main function: safe and stable IT cooling.
- Ready for heat recovery
Our CDUs can be prepared for the system integration of an additional heat exchanger. This allows you to easily extract waste heat for external reuse (e.g., for building heating or local heating networks) – a crucial component for your sustainability goals. - Direct use of waste heat
Highly efficient heat exchangers enable minimal temperature differences – ideal for low-temperature heating networks (e.g., local heating) and local use. - Temperature boost via heat pump technology
Optionally, the system can be expanded with cooling and heat pump technology to raise the temperature level for district heating or industrial applications. - Safety prioritized
Regardless of heat utilization, reliable cooling of IT equipment remains a hydraulic and control priority at all times.
Performance parameters *
depending on ΔT to the on-site cooling medium temperature
Other performance values available on request
Device features *
- Flow pressure and differential pressure control in secondary circuit
- Proactive power adjustment during load jumps (power load anticipation)
- Maximum pressure limitation via the control system (secondary side)
- Frequency-controlled consumer pumps (2 × 50%) with external pressure loss of 3 bar
- Interfaces: BACnet, SNMP, MQTT, Modbus TCP/IP, OPC UA, and many more
Options *
Depending on the ambient temperature
Multiple versions of the secondary circuit pump
Redundant control (hot standby)
Double control valve (parallel/bypass)
Additional heat exchanger
Optionally also with conductivity monitoring
Energy meter
With simultaneous plausibility check
Heat recovery module
Temperature increase using heat pump technology
Future-proof, energy-efficient cooling systems
Your partner for integrated liquid cooling in data centers
Operating modern data centers requires more than just individual components. What is crucial is a consistently coordinated overall system that meets current requirements and is also designed for future power densities.
We support you in setting up your entire cooling circuit:
- from primary supply and building cooling
- to optimally designed CDU systems
- to heat recovery concepts with optional temperature boost (heat pump)
Everything from a single source – technically integrated, reliable, and energy-efficient.
Our CDUs are designed to reliably support the next generation of liquid-cooled data centers – from direct-to-chip applications to large-scale AI (artificial intelligence) and HPC (high-performance computing) infrastructures.
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