Rear Door Heat Exchanger
(RDHx) Active Flow
High-capacity rack
cooling up to 160 kW.
Efficient and Targeted Rack Cooling
Next Generation Cooling’s active RDHx rear door heat exchanger is engineered for precise, predictable thermal control in high-density data centres.
Designed for AI data centres and HPC environments where rack densities exceed 40–160 kW, the NGC RDHx Active Flow eliminates the thermal limitations of conventional air cooling without requiring structural rebuild or extended downtime.
NGC’s rear door heat exchangers respond to server load changes in less than 0.5 seconds, ensuring fast and precise thermal regulation.
- Reduce in energy use up to 90% vs. air-cooled baseline
- Steady operation rapid thermal response and high reliability
- Heat reuse potential up to 56°C outlet temperature
- Full retrofit compatibility installs directly onto existing racks no raised floors
or special containment required
Product Overview
- Lower energy use and improved PUE.
- High uptime with built-in redundancy.
- Scalable design grow rack-by-rack.
- RDHx up to 160 kW per rack.
- Suitable for any rack multiple heights (42–52U) and widths (600–800 mm).
- Maximum energy efficiency with distributed pumping and high water temperature ranges.
- Reliable uptime with built-in redundancy (fans, sensors, power).
- Hot-swappable EC fans for uninterrupted operation.
- BMS-ready with SNMP and MODBUS TCP integration.
- Modular CDU and pump configurations for flexible deployments.
- Cooling capacity: 40–160 kW per rack.
- Airflow: 5,500–10,000 m³/h.
- Fluid flow: 1.6–6.0 m³/h with 29–104 kPa pressure drop.
- Power consumption: 300 W nominal / 1,12
RDHx
Precise, energy-efficient rack-level cooling for AI, HPC and cloud-scale computing.
NGC’s Rear Door Heat Exchanger mounts directly on the rack and removes heat where it is generated. Smart control logic keeps the air outlet temperature within ±0.5 °C, while full redundancy, self-commissioning and BMS integration make it ready for demanding high-density environments.
Distributed pumping explained in 2 minutes
Frequently Asked Questions about our RDHx
Common questions about rear door heat exchangers and how NGC’s Active Flow technology works.
An RDHx mounts on the back of a server rack and cools exhaust air directly — up to 160 kW per rack, no raised floor or room AC changes needed. This makes it easy to retrofit into existing data centers without major infrastructure changes. RDHx units are especially suited to high-density racks where traditional room-based cooling can’t keep up.
Active RDHx units use built-in fans to actively cool exhaust air, reacting fast to load changes. Passive units have no fans of their own and rely on the server’s own airflow to push air through the cooling coil. This makes active units better suited to variable, high-density workloads like AI and HPC, where cooling demand can spike quickly. NGC’s Active Flow is an active RDHx, built specifically for these environments.
NGC’s Active Flow RDHx cuts cooling energy use by up to 90% vs. traditional room-based air cooling. This is because it removes heat directly at the rack instead of cooling an entire room to a safe temperature. Lower energy use also means lower operating costs and a smaller carbon footprint for the facility. It’s one of the main reasons data centers are moving toward rack-level liquid cooling for AI and HPC workloads.
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