High-density racks running AI and GPU workloads routinely draw 30 to 100+ kW each, well beyond what traditional CRAC or CRAH units can dissipate. That gap is pushing data center operators toward precision hydronic cooling, and it puts the design of the chilled water skid at the center of the conversation.
Get the skid right and the whole thermal system performs exceptionally well. Get it wrong and you inherit hot spots, downtime risk, and rising operating costs.
Start with Pump Sizing and Redundancy
Undersized pumps starve high-density racks of flow during peak load; oversized pumps waste energy and accelerate wear. The right approach models flow and pressure drop against your actual rack density mix, then builds in N+1 redundancy so a single pump failure never becomes a cooling outage.
Add VFDs for Real-Time Flow Control
Variable frequency drives let a skid match flow to actual thermal demand instead of running at a fixed rate. As rack loads shift throughout the day, VFDs ease pump wear and cut energy draw without sacrificing cooling headroom.
Manage Glycol Concentration
Glycol protects against freezing and corrosion, but concentration has to be checked and maintained on a schedule. Too little and you lose protection; too much and heat transfer efficiency drops. This is easy to overlook and expensive when it's ignored.
Filter Before You Cool
Inline filtration protects heat exchangers and cooling distribution units (CDUs) from the particulate that causes clogged cold plates and degraded performance, one of the most common failure points in high-density loops. Strainer selection isn't a secondary detail here. It's directly tied to how consistently your cooling and filtration skids perform over the life of the system.
Integrate with the BMS
A skid that reports into your Building Management System enables automated thermal control and alarm monitoring, so load shifts and early warning signs get caught before they become service tickets.
Why Prefabricated Skids Change the Calculus
Field-built systems take longer, introduce more variability, and tie up skilled labor on-site. Hellan's HVAC Packaged Pump Skid Solutions are fully custom-designed using 3D CAD modeling and manufactured in an ISO 9001-2015 environment, then delivered plug-and-play with single-point mechanical connections. That approach typically reduces on-site labor by 15 to 20% compared to stick-built construction, without compromising the customization high-density environments demand. Explore how these systems apply specifically to data center applications.
Get a Design Built Around Your Load Profile from Hellan Strainer
Every high-density deployment has a different rack mix and growth trajectory. Hellan's Design Assist service works from your actual load profile to spec a skid and strainer configuration built for it. Contact our team to get in touch with an expert today!
Frequently Asked Questions About Data Center Racks
How do you calculate the correct flow rate and pressure drop across a chilled water skid serving a mixed-density data center floor?
Model each zone's rack density separately, then size flow and pressure drop to the highest-demand zone while accounting for combined system losses across the full loop, not just an average across the floor.
What is the typical lead time for a custom prefabricated chilled water pump skid, and how does it compare to field-fabricated systems?
Prefabricated skids are built and tested off-site in parallel with facility construction, which generally shortens overall project timelines compared to field-fabricated systems that depend on sequential on-site labor.
How does a prefabricated chilled water skid integrate with a BMS for automated load response and alarm monitoring?
The skid's controls and sensors connect directly into the BMS, allowing automated flow adjustments based on load and immediate alerts when pressure, temperature, or flow readings fall outside set thresholds.