Solution
RDC: an efficient and compact solution integrated directly onto the rack
HiRef collaborated with Oper8 Global, a strategic partner specializing in mission-critical infrastructure, to develop a cooling solution for the data center of a major scientific research campus in the United Kingdom.The project required a solution capable of handling different thermal load densities while maintaining an extremely compact footprint.To meet these requirements, a total of 25 RDC units were supplied:
- No. 20 active RDC units, each with a sensible cooling capacity of 25 kW;
- No. 5 passive RDC units, each with a sensible cooling capacity of 5 kW.
The total installed cooling capacity therefore exceeds 500 kW.
A solution integrated directly onto the racks.
Rear Door Cooling technology makes it possible to intercept the heat generated by IT equipment directly at rack level, reducing the footprint inside data halls. More specifically, RDC units are cooling units installed directly at the rear of the rack, either replacing or supplementing the rear door, with the aim of intercepting and cooling the hot air generated by the servers before it is released back into the room. This configuration allows the thermal load to be managed directly in close proximity to the IT equipment, reducing space requirements and improving the overall efficiency of the cooling system. These units are equipped with a finned coil supplied with chilled water from an external chiller.
For this specific project, both active and passive units were selected according to the thermal load of the individual racks. Active RDC units, equipped with EC fans, ensure controlled airflow through the heat exchanger and are therefore particularly suitable for racks with higher load densities. Passive RDC units, which do not feature fans, instead rely on the airflow generated directly by the servers through the coil, making them suitable for racks with lower thermal loads. The units were also customized from a construction standpoint to suit the specific installation requirements. The RDC units were manufactured in a 45U configuration, taller than the more common 42U rack format, and equipped with dedicated flanges for direct connection to the rack. The hydraulic connections were also arranged at the bottom of the unit, allowing connection to the pipework installed beneath the raised floor.
Operational continuity and simplified maintenance.
The active units are equipped with EC fans installed on replaceable modules, designed to allow maintenance on the ventilation system without interrupting unit operation. Another distinctive feature of HiRef RDC units is the door opening angle of up to 180°, providing easy access to the rack during server maintenance activities. The combination of compact dimensions, accessibility and direct integration with the rack makes Rear Door technology particularly suitable both for small and medium-sized data centers and as a complementary solution within more complex infrastructures. In hybrid systems with Direct-to-Chip cooling, RDC units can in fact contribute to dissipating approximately 20–30% of the residual heat generated by the servers, working alongside CDUs, which manage the main share of the thermal load directly at component level.
The project represents another milestone in the well-established collaboration between HiRef and Oper8 Global, a synergy that continues to translate into the development of highly customized solutions, designed to precisely meet the specific requirements of the end customer.