Views: 0 Author: Site Editor Publish Time: 2026-11-02 Origin: Site
At CSTHEATEXCHANGER, we design and manufacture high-density 100kW In-Rack Coolant Distribution Units (CDUs) with N+1 Redundant Variable-Speed Pumps engineered specifically for hyperscale AI clusters, GPU server racks (NVIDIA H100/H200/B200, AMD Instinct MI300), and high-performance computing (HPC) direct-to-chip (DTC) liquid cooling deployments. Packaged into a compact 4U to 8U EIA-310 / OCP-compliant 19" or 21" rack-mount chassis, our 100kW in-rack CDUs hydraulically isolate the primary facility water system (FWS) from the secondary technology cooling system (TCS) using a high-thermal-density SS316L / Titanium brazed plate heat exchanger (BPHE). Featuring dual intelligent brushless DC / magnetic-drive canned-motor pumps with bumpless automatic failover (<50 ms), integrated 50 μm duplex filtration, dynamic differential pressure (ΔP) bypass regulation, and Redfish / SNMP / Modbus automation, CSTHEATEXCHANGER in-rack CDUs deliver precise coolant delivery (80 to 160 L/min) at sub-1.031.03 PUE thermal efficiency with zero server downtime.
As AI compute racks surge past 60 kW to 100 kW+ per enclosure, rack-level CDUs eliminate the need for massive row-level piping while isolating delicate server micro-channel cold plates from harsh building chilled water loops:
CSTHEATEXCHANGER® 100kW IN-RACK CDU HYDRAULIC SCHEMATIC
=================== PRIMARY FACILITY WATER SYSTEM (FWS) ===================
[ Facility Supply: +30°C to +45°C (Warm Water Cooling W32-W45 / Dry Cooler) ]
│ ▲
2-Way Control Valve Modulating Return
│ │
▼ │
┌────────────────────────────────────────────────────────────────────────────┐
│ CSTHEATEXCHANGER® SS316L HIGH-DENSITY BRAZED PLATE HEAT EXCHANGER (BPHE) │
│ Thermal Capacity: 100 kW @ Approach Temp 3K - 5K │
└────────────────────────────────────────────────────────────────────────────┘
│ ▲
Cold Coolant Supply: +40°C to +50°C Warm Return: +55°C to +65°C
│ │
▼ │
┌────────────────────────────────────────────────────────────────────────────┐
│ N+1 REDUNDANT VARIABLE-SPEED PUMP ARRAY (SEAMLESS BUMPLESS FAILOVER) │
│ ┌───────────────────────────┐ ┌───────────────────────────┐ │
│ │ PUMP 1: PRIMARY (ACTIVE) │ ◄─► │ PUMP 2: STANDBY (BACKUP) │ │
│ │ Brushless DC Canned Motor │ │ Dual Check Valves Isolation│ │
│ └───────────────────────────┘ └───────────────────────────┘ │
│ Flow Rate: 80 - 160 L/min | Head: 1.5 - 2.8 bar | Integrated Duplex Filter │
└─────────────────────┬──────────────────────────────────────────────────────┘
│ ▲
▼ │
================ SECONDARY TECHNOLOGY COOLING SYSTEM (TCS) ================
[ Direct-to-Chip (DTC) Server Loops: GPUs, CPUs, Memory Cold Plates & CDUs ]Primary Loop (Facility Side): Connects to external dry coolers, cooling towers, or central chillers. Operates with standard industrial water/glycol mixtures.
Secondary Loop (IT Technology Side): Dedicated closed loop utilizing treated deionized water with specialized biocides and corrosion inhibitors (PG25/DI water), preventing scale, sediment, and bio-growth from fouling ultra-dense 0.1 mm0.1 mm cold plate micro-fins.
Our compact multi-plate SS316L heat exchanger achieves a tight thermal approach temperature of 3K to 5K, enabling warm-water cooling (+32∘C to +45∘C facility supply water) and maximizing year-round 100%100% free cooling without mechanical compressor refrigeration.
Server downtime in a 100kW AI rack costs thousands of dollars per minute. CSTHEATEXCHANGER in-rack CDUs integrate true continuous-operation redundancy:
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CSTHEATEXCHANGER 100kW IN-RACK CDU VS. CONVENTIONAL SINGLE-PUMP CDUs
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Engineering Feature Conventional Single-Pump CDU CST 100kW Dual-Pump Redundant In-Rack CDU
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Pump Redundancy Architecture Single Pump (1N) — Single Point Dual N+1 Active/Standby or Load-Sharing (2N)
Pump Failover Switchover Time Complete Cooling Loss / Trip Bumpless Instant Failover (< 50 ms)
Pump Drive Metallurgy Standard Mechanical Shaft Seal Sealless Magnetic-Drive / Canned Motor
Chassis Form Factor Bulky 10U - 14U Footprint Ultra-Compact 4U / 5U / 6U / 8U Chassis
Filtration System Single In-Line Strainer Duplex 50 µm Filter with ΔP Alarm Sensors
Data Center Management Protocol Basic Modbus RTU Only Redfish API, SNMP v3, BACnet IP, Modbus TCP
Leak Detection & Mitigation Local Buzzer Only Multi-Zone Optical/Rope Sensors + Auto-Shutoff
Quick Disconnect Interface Standard Threaded Fittings Blind-Mate / Non-Spill Universal QDs (UQD)
================================================================================ BUMPLESS FAILOVER MECHANISM: CONTINUOUS TCS PRESSURE PROFILE
SYSTEM PRESSURE (bar)
3.0 ┤
│ ─── PUMP 1 OPERATING ───┐ ┌─── PUMP 2 OPERATING ───
2.2 ┤ │ < 50 ms │
│ └── TRANSITION ─┘ (ZERO CAVITATION / NO PRESSURE DIP)
1.0 ┤
└───────────────────────────────────────────────────────────────────► TIME (ms)Eliminates traditional mechanical shaft seals that degrade over time. The hermetically enclosed canned-motor design ensures 0%0% external coolant leakage risk and provides continuous MTBF ratings >100,000 operating hours>100,000 operating hours.
High-speed internal microcontrollers continuously monitor pump tachometer feedback, differential pressure (ΔPΔP), and electrical current. If pump 1 experiences an anomaly, pump 2 ramps to full operational speed within <50 ms<50 ms, maintaining constant pressure and flow across GPU cold plates with zero thermal throttling or cavitation.
CSTHEATEXCHANGER 100kW In-Rack CDUs integrate all required fluid management subsystems into a single slide-out rack chassis:
COMPREHENSIVE FLUID CONDITIONING & SENSING SUITE
[1. DUPLEX 50 µm / 20 µm PARTICULATE FILTRATION]
• Parallel filter housings with differential pressure transducers.
• Allows live online filter element replacement without interrupting liquid flow.
─────────────────────────────────────────────────────────────────────────────
[2. AUTOMATIC AIR DEAERATION & EXPANSION CHAMBER]
• Stainless steel expansion vessel with internal micro-bubble separator.
• Automatically bleeds entrained air pockets to maintain peak heat transfer.
─────────────────────────────────────────────────────────────────────────────
[3. MULTI-ZONE LEAK CONTAINMENT & EMERGENCY ISOLATION]
• Deep drip containment tray with optical moisture sensors and sensing rope.
• Automatic fast-acting motorized isolation valves isolate FWS/TCS loops.(Note: The following engineering parameters represent standard manufacturing design envelopes. Dimensions, quick disconnect types, pipe connection sizes, and pump head ratings are tailored to specific server rack form factors and OEM specifications.)
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CSTHEATEXCHANGER 100kW IN-RACK COOLANT DISTRIBUTION UNIT (CST-CDU-100R)
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Engineering Parameter Standard Manufacturing & Design Range
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Rated Thermal Cooling Capacity 100 kW @ 3K - 5K Approach Temperature (Scalable 80 - 120 kW)
Chassis Mounting Form Factor Standard 19" or 21" OCP Rack-Mount (4U / 5U / 6U / 8U Height)
Pump Redundancy Architecture N+1 Redundant (Dual Canned-Motor or Mag-Drive ECM Pumps)
Secondary Coolant Flow Rate 80 to 160+ L/min (21 to 42+ GPM) Continuously Modulated
Secondary Coolant Head Pressure 1.5 to 3.0 bar (21.7 to 43.5 psi) Differential Pressure
Brazed Plate Exchanger Core Vacuum-Brazed Stainless Steel 316L / Titanium Plates
Compatible Coolants Deionized Water (DI-Water), PG25/EG25 (Inhibited Glycol), Novec
Facility Water Supply (FWS) +25°C to +45°C (Compatible with ASHRAE W1 to W5 Classes)
Technology Cooling Supply (TCS) +30°C to +50°C (Optimized for Direct-to-Chip Cold Plates)
Filtration Rating Integrated Duplex 50 µm (Optional 20 µm) with ΔP Monitoring
Internal Fluid Expansion Tank Sealed Stainless Steel Vessel with Microbubble Air Separator
Power Supply Input Options Dual Redundant 200-240V AC (1-Phase) or 48V / 12V DC Busbar
Communication & Monitoring Redfish API, SNMP v3, Modbus TCP/RTU, BACnet IP, Dual GbE LAN
Leak Detection System Internal Optical Sensor, Continuous Rope Sensor, Auto Shutoff
Hydraulic Quick Disconnects Blind-Mate Dripless Couplings / Universal Quick Disconnects (UQD)
Quality, Safety & EMC Codes UL 62368-1, CE, RoHS, REACH, ISO 9001:2015, IP54 Front Panel
================================================================================An in-rack CDU provides dedicated, localized thermal management directly inside the server cabinet. It eliminates large sub-floor coolant distribution headers, simplifies modular data center expansion (one rack at a time), reduces secondary piping coolant volume, and allows custom temperature and flow tuning for individual high-density GPU nodes.
Both canned-motor pumps are equipped with independent check valves and dedicated variable-frequency drives. When the primary pump controller detects an RPM or pressure drop, the standby pump ramps up within <50 ms<50 ms. The check valve on the primary pump automatically seals, preventing reverse backflow and maintaining steady coolant delivery to the computing cold plates.
Yes. With our high-efficiency SS316L brazed plate heat exchanger, CST in-rack CDUs operate with facility water temperatures up to +40∘C to +45∘C (ASHRAE W4/W5 compliance). This allows data centers to operate with dry coolers alone across most global climates, achieving PUE levels below 1.031.03.
Equip your AI and high-density compute server racks with precision thermal management from CSTHEATEXCHANGER:
100kW High-Density In-Rack CDUs in Ultra-Compact 4U/5U/6U/8U Enclosures
N+1 Dual Canned-Motor / Mag-Drive Redundant Pumps with <50 ms Seamless Failover
High-Efficiency SS316L / Titanium Brazed Plate Exchangers (3K to 5K3K to 5K Approach)
Integrated Duplex Filtration (50 μm), Expansion Chamber, and Micro-Bubble Deaeration
Comprehensive Redfish, SNMP v3, and Modbus TCP Telemetry & Control Integration
Custom OEM 2D/3D CAD Modeling, Piping Configuration, and Direct Factory Supply
Contact our data center liquid cooling engineering team today with your rack thermal load, flow rate requirements, primary water temperatures, and chassis height limits for technical proposals and factory-direct quotations.
Website: https://www.cstheatexchanger.com/
Technical Inquiries: info@cstheatexchanger.com
