As AI workloads reshape the data center landscape, one question keeps coming up for operators and engineers alike:
Which CDU (Cooling Distribution Unit) fits my environment best?
At Nautilus, we designed the EcoCore CDU product line to meet operators wherever they are on their liquid-cooling journey, from in-row retrofits to full facility-scale integration. The EcoCore RCD and EcoCore FCD share the same foundation of field-proven reliability, rapid deployment, and flexible design, but theyโre optimized for different installation approaches and operational priorities.
EcoCore RCD: Compact Power for In-Row and Data Hall Applications
The EcoCore RCD is Nautilusโs most compact, adaptable CDU, purpose-built for in-row, data hall placement where space is at a premium and cooling demand is high.
Itโs ideal for colocation providers and enterprise operators who need to retrofit for AI workloads quickly, without major construction or reconfiguration.
Key Highlights:
- Capacity: Up to ~2.5 MW, with built-in pump redundancy and high thermal headroom.
- Ideal for: Colos, enterprise AI deployments, or incremental retrofits where cooling must live on the data hall floor.
- Design advantage: Compact footprint with flexible integration that adapts easily to different site layouts
- Use case: Perfect when you need high-density liquid cooling inside the hall.
If your cooling challenge sits within the rack rows themselves, the RCD gives you a high-performance, drop-in solution that aligns with current in-row expectations.
EcoCore FCD: Facility-Scale Cooling – For New Builds and Retrofits
The EcoCore FCD (formerly EcoCore COOL) is Nautilusโs flagship CDU โ designed for facility-scale or data hall-wide cooling, yet agile enough for retrofit projects.
Unlike in-row CDUs, the FCD is deployed in a mechanical gallery or adjacent space off the data hall floor. That makes it a perfect choice for retrofits where you canโt sacrifice IT floor space but need to scale cooling capacity fast.
Each unit delivers 2-4 MW of capacity, able to modularly link 6 units, and includes Nautilusโs variable-pressure Leak Prevention System (LPS), enabling true leak-proof operation across the entire TCS network.
Key Highlights:
- Capacity: 2โ4 MW per unit, scalable to 10 MW+.
- Ideal for: Hyperscalers, colos, or enterprises needing whole-hall or facility-level cooling – new or existing sites.
- Retrofit-ready: Deployed in mechanical galleries or adjacent spaces without disrupting IT operations.
- Operating modes:
- LPS Mode: leak-proof reliability
- Hybrid Mode: Balances leak prevention with higher flow for mixed loads.
- +P Configuration: Peak-pressure performance for advanced GPU clusters.
- Design advantage: Integrated degassing, buffer tank, and common header for true thermal load balancing.
- Deployment speed: Order-to-delivery in as little as 12 weeks.
If your goal is facility-wide thermal efficiency, whether for a greenfield project or a retrofit expansion, the FCD delivers scale and resilience in one modular package.
RCD vs. FCD: Choosing the Right CDU for Your Environment
| Category | RCD | FCD |
| Cooling Capacity | Up to ~2.5 MW | 2โ4 MW per unit (10 MW+ scalable) |
| Deployment Location | In-row / data hall floor | Mechanical gallery / adjacent space |
| Ideal Use Case | Incremental retrofits, colos, smaller AI clusters | Scalable capacity retrofits, hyperscalers, or full-facility cooling |
| Unique Feature | Compact form factor with built-in redundancy | Variable-pressure Leak Prevention System (LPS) |
| Scalability | Multi-MW | Parallel, thermally coupled operation |
| Lead Time | Available to ship Q1 2026 | 12-16 weeks |
| Value Proposition | Rapid retrofit and space-efficient cooling | Facility-scale reliability and leak-proof performance |
When to Choose Each
- Choose the RCD if:
You need liquid cooling inside the data hall – fast, compact, and easy to integrate with existing layouts.
- Choose the FCD if:
Youโre expanding or retrofitting a facility and want to add high-density, leak-proof cooling capacity from the mechanical gallery or adjacent space, without interrupting IT operations.
The Common Thread: Proven by 400,000+ Unit Hours of Operation
Both CDUs are built on over 400,000 unit hours of direct-to-chip cooling experience from Nautilusโs operational AI data center, real-world validation no other CDU manufacturer can match.
That experience is what enables Nautilus to deliver the shortest lead times, most flexible deployment options, and highest operational confidence in the market.
The Bottom Line
Whether youโre cooling within the data hall or expanding beyond it, thereโs an EcoCore CDU designed to fit your scale, timeline, and future growth.
EcoCore RCD: Compact, quick-deploy, retrofit-ready for in-row applications.
EcoCore FCD: High-capacity, leak-proof, retrofit-friendly for facility-level cooling.
AI wonโt wait for cooling. With Nautilus, neither will you
