Meeting the increasing demands of high-density data centers with CDUs

The rise of AI has reshaped the conversation around data center design. As AI workloads surge and GPUs become more powerful, the need for scalable cooling solutions has accelerated across the board. Put in simple terms: Rack densities are increasing, and with them, the need for more efficient heat management. Amidst this ongoing transformation, liquid cooling has become a primary subject of conversation and part of that narrative is the critical role that a CDUs play in this transition.

How liquid cooling became a data center priority

In many ways, the momentum shift began in 2023, sparked by the explosion of gen-AI tools and the realization amongst both the public and especially hyperscalers of the fundamental transformation taking place. As conversations around power usage, rack densities and thermal management keep evolving, liquid cooling has become a key topic and part of the broader push for innovation that's happening in the data centers' landscape.

And it's one of the many reasons why Johnson Controls has made significant strategic investments – particularly in thermal innovation – to meet the demands of the industry. "We want to become the market leading innovative experts globally within the data center market on how we optimize the cooling chain," says Todd Grabowski, President of Data Center Solutions at Johnson Controls.

And it is the close relationship with partners and clients that has allowed for the organization to constantly think of customer-led innovations and solutions, including the newly announced Silent-Aire CDU. You can hear more about that announcement here .

What the Silent-Aire CDU does and how it works

The Silent-Aire CDU is a versatile alternative to traditional air conditioning systems and specifically designed to meet the high-performance demands of hyperscalers and data center operators. By enabling placement near the equipment that requires cooling, it conserves energy by eliminating the need to circulate coolant over a large area. This optimization of power consumption and enhancement of system reliability contribute to significant long-term operating expense reductions.

Multiple units can share operational data and adjust flow rates and cooling capacity dynamically to optimize energy and balance loads across varying server loads, which can help automate redundancy in the event of failure. CDUs are also able to act autonomously to respond to conditions in the rack.

When combined with a YVAM chiller, average PUE values of 1.2 are achievable, ranging from a PUE of 1.18 in Dublin, to a PUE of 1.24 in Dubai, and providing predictable performance in a variety of environments.

And when it comes to the CDU, Silent-Aire and Johnson Controls bring decades of thermal management, controls engineering and manufacturing expertise that closely align with today's global data center requirements.

Global scalability with regional adaptability

"We have the global footprint and global engineering capability, and we are able to meet our clients' requirements in North America, across EMEA and all over APAC", says John Keane, Vice President and General Manager, Silent-Aire EMEA and APAC. "It's not just about having the right product and solution. It's about having the infrastructure and system in place to deliver it and support it at scale for the clients."

Meeting the market where it's headed

While hyperscalers are the primary drivers of this shift, the effects can be felt across the industry. Co-location providers, consulting engineers and OEMs are all engaging in conversations around liquid cooling. Johnson Controls is not simply responding to these conversations but also making sure that the technology and solutions developed align with the business needs of the operators.

"We meaningfully want to participate in this market, drive this market and support this customer set," says Austin Domenici, Vice President and General Manager, Data Center Solutions at Johnson Controls. "We don't want to launch anything that we can't do at quality or at scale so our customers can really trust what we're doing."

As the data center landscape continues to evolve, Johnson Controls is committed to staying at the forefront of innovation.

"The CDU is a part of a much wider delivery mechanism that's at the core of our strengths at Johnson Controls", says John Keane. "This is a natural progression for us, and it proves that we're a real player in the liquid cooling conversation for data centers, which positions us very strategically on how we can further support customers in the future."

FAQs

What is a Coolant Distribution Unit (CDU) in a data center?

A CDU is a liquid cooling system that circulates coolant between heat-generating IT equipment – such as GPU racks – and the facility's broader cooling infrastructure. Unlike traditional air conditioning, CDUs can be placed near the racks they serve, eliminating the need to circulate coolant across large areas. This proximity reduces energy waste and improves cooling precision for high-density deployments.

What PUE can a CDU achieve when paired with a chiller?

When paired with a YORK YVAM chiller, the Silent-Aire CDU can achieve PUE values of 1.2 and below – ranging from 1.18 in cooler climates like Dublin to 1.24 in hotter environments like Dubai. This provides predictable performance across a variety of geographies.

Can CDUs provide redundancy if a cooling unit fails?

Yes. Multiple Silent-Aire CDUs can share operational data and dynamically adjust flow rates and cooling capacity to balance loads across varying server demands. This coordination can help automate redundancy in the event of a unit failure and individual CDUs can also act autonomously to respond to conditions in the rack.