Motivair Cool News

With the evolution of data centers due to increasing AI workloads comes a heightened focus on addressing one major challenge: heat.

The servers behind today’s AI technology deliver extraordinary levels of performance, but they also generate significantly more heat than traditional workloads. As rack densities scale and cooling requirements intensify, liquid cooling has dominated conversations regarding the most effective way to manage heat within data centers. And central to these conversations is the coolant distribution unit (CDU).

While CDUs play a critical role in high-performance computing environments, choosing the right model is about more than just selecting the product that has sufficient capacity. The decision requires data center operators to think critically about the thermal management needs they have today and the trajectory they’d like their facility to take tomorrow.

Understand the Actual Role of the CDU

It’s imperative to fully understand the role the CDU will play in your operation before you even begin to consider which model to buy.

The CDU is the bridge between a data center’s facility water line and the secondary loop that serves liquid-cooled IT equipment. The architecture of the CDU includes pumps, heat exchangers, controls, and monitoring systems that allow it to transfer heat from the server back to the facility’s cooling system while still maintaining the coolant temperature, flow, and pressure required by the IT equipment.

In many ways, the CDU is the operational heart of a liquid cooling deployment. Its performance influences not only cooling effectiveness, but operational efficiency and future scalability.

Evaluate Your Servers and Existing Infrastructure

Even when two organizations contain similar compute environments, their cooling strategies may look very different. That's because a CDU must ultimately operate within the realities of the facility itself and must align with the servers the operator has chosen to deploy. So naturally, the first step in selecting a CDU is taking the time to truly understand the operational realities of your data center, so that it will eventually be integrated in the most effective way possible.

Server specifications influence CDU selection by determining the thermal load, coolant flow requirements, pressure-drop characteristics, and operating temperatures the cooling system must support. This is especially important in AI environments built on NVIDIA architectures like Rubin. As each new generation of GPUs delivers greater computing performance, it also generates higher heat loads that must be removed to maintain efficiency and uptime.

All the power consumed by a GPU is converted to heat, so, for example, a 2,300-watt GPU will generate 2,300 watts of heat that cooling infrastructure must work continuously to remove. But a server rack won’t contain just one of these GPUs; it can hold up to 72 in total. Assuming a rack contains 72 of these next-generation 2,300-watt GPUs, roughly 165 kilowatts of heat would need to be rejected. That is roughly equivalent to 50 average home furnaces running at full capacity. And that 165 kilowatts of heat doesn’t even account for other IT equipment like CPUs.

This level of heat requires the facility’s cooling technology to move more coolant, maintain tighter temperature control, and transfer significantly more heat away from the chip. The CDU is central to liquid cooling architecture in these facilities as a result, because its capacity, flow performance, controls, and reliability are necessary in supporting next-generation AI infrastructure.

Additionally, factors such as facility water temperatures, available floor space, and existing cooling infrastructure all influence CDU deployment decisions. And data center operators who must retrofit their existing environments often face different considerations than those who design new facilities from the ground up.

For example, facility water conditions can significantly influence CDU design considerations. Some CDU installations may benefit from water temperatures that improve overall cooling efficiency, while others may require tighter environmental controls based on operating conditions.

Evaluating these conditions as a first step in the selection process will help ensure that the CDU you eventually deploy aligns with both your facility's capabilities and long-term operational goals.

Think Beyond Capacity

When you evaluate CDU models, remember that while cooling capacity is undoubtedly important, it only tells part of the product story.

Overall system performance is influenced by several factors, including flow control, pressure management, heat exchanger performance, pump redundancy, controls architecture, and monitoring capabilities. A CDU that meets your capacity requirements on paper may not necessarily be the best fit if it cannot perform in other areas.

For example, maintaining appropriate coolant flow rates throughout the secondary cooling loop is critical to effective heat removal at the server level. Likewise, stable pressure management helps ensure consistent performance across liquid-cooled equipment.

As cooling infrastructure becomes more sophisticated, data center operators are increasingly evaluating how efficiently a CDU performs across a range of operating conditions rather than focusing exclusively on its peak capacity. The right CDU should be capable of meeting performance requirements not only during day-to-day operation, but also during future expansion and evolving AI requirements.

Plan for Scalability from Day One

If there’s one thing that’s evident about the AI landscape, it’s that it continues to grow rapidly.

Data center operations continue to deploy more powerful servers that increase rack density and expand overall compute capacity to support AI’s continued evolution. And as a result, cooling infrastructure must be able to keep up and scale alongside the facility it is supporting.

When you consider different CDU models, it’s imperative that you consider not only the needs your operation has today, but those it may have in five or even ten years. Choosing a CDU that has the ability to scale will benefit your operation greatly, enabling it to:

• Accommodate future rack density
• Expand infrastructure with minimal disruption
• Reduce the need for costly redesigns
• Maintain operational efficiency as AI workloads evolve

Designing your data center’s cooling infrastructure with scalability in mind is much more efficient than retrofitting your infrastructure after the limits of your cooling technology have been reached.

Take Redundancy and Reliability into Account

Because liquid cooling solutions have become so intertwined with high-performance computing environments, it is essential that they come with features that ensure redundancy and reliability. Any disruption to your cooling technology will in turn cost your facility uptime, and the best liquid cooling solutions are the ones built with your long-term operational success in mind.

The truth is that the strength of a CDU is no longer measured just by how well it removes heat; its success is measured in how consistently it can perform over years of operation. A well-designed CDU will support operational continuity while granting you the ability to monitor system performance and respond proactively to changing conditions in your facility.

Because of this, features such as redundant pumping architectures, intelligent controls, system monitoring, and serviceability are critical to consider during the selection process. These features come standard across the Motivair by Schneider Electric portfolio of CDUs, providing extensive visibility into operating conditions, monitoring variables such as coolant temperature, pressure, flow rates, and overall system health. This level of insight will help you identify issues earlier, optimize performance, and maintain confidence in your cooling infrastructure.

CDU Selection Requires a Strategic Approach

The evolving nature of AI is driving a fundamental shift in how data centers approach thermal management. As computing power grows and densities continue to increase, cooling infrastructure like CDUs have become a strategic enabler of performance and growth.

The CDU selection process involves striking a fine balance between the operational needs you have today with what AI might require of your facility tomorrow. Understanding your facility’s operational conditions, considering overall performance, prioritizing redundancy and reliability, and planning for scalability are all necessary to select the model best fit for your data center.