Liquid Cooling in Data Centres: Key Hoses and Components

Why Liquid Cooling in Data Centres Is Growing

For many years, data centres relied mainly on chilled air delivered through raised floors and ducts. As power density increased, it became harder to remove enough heat with air alone. And the advent of AI-driven demands has only amplified these challenges. This is why many facilities now use hybrid or fully liquid-cooled configurations. As demand evolves, data centre cooling technology must support higher thermal loads while maintaining uptime and reliability.

Depending on the design, liquid cooling in data centres may use:

• Direct-to-chip cold plates, where coolant flows through plates mounted on CPUs and GPUs
• Immersion systems, where servers are submerged in a dielectric fluid
• Rear-door heat exchangers, which remove heat from exhaust air at the back of each rack

These systems are engineered by equipment manufacturers and consulting engineers, but they all share a common need: reliable hose assemblies and couplings that keep coolant moving safely through the loop.

Understanding Data Centre Liquid Cooling

To understand why many operators are adopting data centre liquid cooling systems, it helps to look at the physics behind them and the practical benefits for high-density environments. Liquids simply move heat differently than air, which changes what is possible inside modern racks and data rows.

Why Liquid Removes Heat More Effectively Than Air

The key lies in basic thermodynamics. Liquids, particularly water and specialized coolants, have much higher thermal conductivity and specific heat capacity than air. This means they can absorb and transfer significantly more heat, even at lower flow rates.

For example, a given volume of water can store thousands of times more thermal energy than the same volume of air. This efficiency allows data centres to cool high-density equipment with smaller heat-transfer surfaces, fewer air-handling requirements, and potentially lower overall energy consumption when systems are properly designed.

Benefits for High-Density Racks

As more processing power is packed into smaller spaces, data centre cooling strategies need to adapt. Liquid cooling systems can provide a more consistent thermal environment around critical components, reducing the risk of hotspots and thermal throttling. This helps operators make better use of high-performance servers without compromising stability.

By incorporating liquid-cooled server racks as part of the overall cooling strategy, facilities may be able to:

• Operate higher-density configurations
• Extend hardware life cycles by reducing thermal stress
• Reduce reliance on large, energy-intensive air-handling infrastructure
• Improve Power Usage Effectiveness (PUE) over time when systems are optimized as a whole

Types of Liquid Cooling Systems

Different approaches to liquid cooling exist, each with specific benefits depending on application scale, heat load, and deployment strategy. In most cases, these systems are selected and engineered by OEMs and consulting engineers. The main categories used in today’s data centres include:

Direct-to-chip (cold plate) cooling

Cold plate cooling uses metal plates affixed to CPUs, GPUs, and other high-power components. Coolant circulates through these plates, absorbing heat directly from the hottest parts of the system. This approach is well suited for high-performance workloads.

Immersion cooling

In immersion cooling, servers are submerged in dielectric cooling fluid. This method eliminates the need for server fans and can significantly reduce energy use. Because it allows heat to be dissipated directly from all components, immersion is popular in AI, blockchain, and other compute-intensive environments where performance and thermal stability are critical.

Rear-door heat exchangers (RDHx)

Rear-door heat exchangers integrate into standard server racks. As hot air exits the servers, it passes through a fluid-filled coil that absorbs and removes the heat. These systems help facilities transition from air cooling to hybrid or more liquid-intensive strategies.

Liquid Cooling System Components

An effective data centre liquid cooling setup typically combines several engineered components that work together as a system:

• Coolant distribution units (CDUs) regulate coolant flow and pressure, monitor temperatures, and often connect to building management systems.
• Heat exchangers and pumps move heat from the coolant to a secondary loop or ambient environment and keep fluid circulating through the system.
• Liquid-cooled server racks incorporate integrated plumbing, cable management, and safety features such as leak detection or backup lines.
• Cooling fluids may include treated water, glycol-based mixtures, or specialized dielectric fluids, each with different viscosity, thermal performance, and compatibility requirements.

These elements are selected and specified by the design and engineering team. Across all of them, reliable hose assemblies and secure connections are essential to move coolant safely between components and support long-term uptime.

What to Look for in Hoses for Liquid Cooling in Data Centres

When a facility adopts liquid cooling in data centres, hose selection becomes a critical factor. A leak, burst, or poorly routed assembly can damage hardware, cause downtime, and introduce safety risks. Working with your engineering and integration partners, it is important to choose hose assemblies that match the demands of the application.

• Pressure and temperature ratings

Hoses must be rated for the operating pressure and temperature of the coolant loop, with an appropriate safety margin. In some cases, different loops within the same facility may require different hose constructions, depending on how and where they are installed.

• Compatibility with cooling fluids

Coolants can include treated water, glycol-based mixtures, or specialized dielectric fluids. Hose inner tubes and cover materials need to be compatible with the chosen fluid to avoid swelling, degradation, or contamination over time. Confirming compatibility up front helps support long-term reliability.

• Flexibility and routing in tight spaces

Racks, containment aisles, and equipment rooms often leave very little space for large bend radii. Hoses should be flexible enough to route cleanly without kinking or placing excess stress on fittings. Well-planned routing also makes maintenance and future expansion easier.

• Leak prevention at connection points

Most issues in liquid cooling in data centres occur at the connections, not in the hose body. Reliable coolant transport depends on durable, leak-resistant hoses and secure, quick-disconnect couplings. High-quality assemblies help maintain stable flow, simplify servicing, and support safe operation in dense rack environments. Solutions such as Gates Data Master™ hoses paired with UQD couplings can provide flexibility, chemical compatibility, and quick servicing for modern liquid-cooled data centre systems.

• Testing, documentation, and traceability

For mission-critical environments, it is important to know that hose assemblies have been pressure-tested and built to consistent standards. Working with a hydraulic hose distributor who documents testing and maintains build records can support your own maintenance plans, quality programs, and compliance requirements.

These hose-level considerations help ensure that the liquid cooling systems designed by your engineering team can be installed, operated, and maintained with confidence over the long term.

How Marshall Equipment Supports Liquid Cooling in Data Centres

Marshall Equipment supplies hoses, couplings, and custom assemblies for liquid cooling in data centres across Central and Eastern Canada. We work alongside mechanical engineers, OEMs, and integrators to match hose constructions and fittings to each project’s pressure, temperature, and routing requirements.

Drawing on our experience in hydraulic and industrial hose applications, we can help you:

• Identify hose options compatible with your selected cooling fluids
• Specify suitable quick-disconnects and couplings
• Design assemblies that support clean routing and easier maintenance
• Provide tested, documented assemblies for mission-critical environments

We do not replace the work of your engineering firm or system designer. Our focus is on supplying reliable hose assemblies that support the safe, efficient operation of your liquid-cooled infrastructure.

To learn more, visit our data centre cooling solutions page or contact Marshall Equipment to discuss the hose requirements for your next project.