QuickSpecs
HPE Rear Door Heat Exchanger QuickSpecs
RDHX are designed to complement any new or existing datacenter by enabling computing power growth without adding to the heat load in the datacenter.
HPE Rear Door Heat Exchanger (RDHX) is a liquid to air heat exchanger cooling system that removes the high levels of heat generated by today’s servers, mass storage, and core networking hardware. It is mounted directly to the rear panel of HPE racks. RDHX are compatible with 42U or 48U racks with a range of IT capacity when used under certain load and site conditions.
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Air flow of RDHX fully supports industry-standard front-to-back cooling designs and standard server dimensions. Hot air exiting the rear of the servers is neutralized as the air is cooled down via the coils in the RDHX. It can connect directly to facility water feed or to a CDU depending on the dewpoint temperature of the datacenter room. Top or bottom liquid feed options are supported. Mural graphics on the Doors are also supported. RDHX can also be deployed with Direct Liquid Cooling (DLC) to increase the percentage of heat capture to water, meeting room-neutral requirements.
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RDHX with 42U or 48U Rack Options
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Key Features
General Solution
- – Liquid to air heat exchanger cooling system attached to back of a standard IT rack
- – Hot air exhaust from the server moves through cooling coils to remove the heat
Cooling Capacity (kW per rack)*
- – M12: 14-35kW
- – M14: 35-55kW
Notes: *See RDHX Site Planning Guide for additional information and specifications
Water
- – Accommodates facility water temperatures 2° C (4F) above maximum anticipated dew point
- – Accommodates water pressure between 25 and 100 psi (172 – 689 kpa)
- – For water temperatures at or below the dewpoint, a Cooling Distribution Unit (CDU) will be required to create a secondary warmer water loop to supply the doors
Power
- – Input power support for 208V / 230V / 277V (1-phase)
Flexibility
- – HPE 42U or 48U racks for IT equipment are supporting shipping of fully integrated rack solutions (HPE Factory Express or Partner rack integration) as these are delivered on shock pallet
- – Underfloor and overhead plumbing capabilities
- – Full services offering available, including planning, deployment and maintenance
Agency Certifications
- – ETL, CSA, CE Certified
Each RDHX SKU includes
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| For 42U 600mm HPE G2 Racks (P9K10A) and Heavy Racks (R4L97A) | |
| HPE M12 42U 600mm G2 Rack 208-230V Top Feed Rear Door Heat Exchanger | S4M97A |
| HPE M14 42U 600mm G2 Rack 208-230V Top Feed Rear Door Heat Exchanger | S4M98A |
| HPE M12 42U 600mm G2 Rack 208-230V Bottom Feed Rear Door Heat Exchanger | S4M99A |
| HPE M14 42U 600mm G2 Rack 208-230V Bottom Feed Rear Door Heat Exchanger | S4N00A |
| HPE M14 42U 600mm G2 Rack 260-290V Top Feed Rear Door Heat Exchanger | S4N01A |
| HPE M14 42U 600mm G2 Rack 260-290V Bottom Feed Rear Door Heat Exchanger | S4N02A |
| For 42U 800mm HPE G2 Racks (P9K48A) and Heavy Rack (R4M95A) | |
| HPE M12 42U 800mm G2 Rack 208-230V Top Feed Rear Door Heat Exchanger | S4N03A |
| HPE M14 42U 800mm G2 Rack 208-230V Top Feed Rear Door Heat Exchanger | S4N04A |
| HPE M12 42U 800mm G2 Rack 208-230V Bottom Feed Rear Door Heat Exchanger | S4N05A |
| HPE M14 42U 800mm G2 Rack 208-230V Bottom Feed Rear Door Heat Exchanger | S4N06A |
| HPE M14 42U 800mm G2 Rack 260-290V Top Feed Rear Door Heat Exchanger | S4N07A |
| HPE M14 42U 800mm G2 Rack 260-290V Bottom Feed Rear Door Heat Exchanger | S4N08A |
| For 48U 600mm HPE G2 Racks (Rack SKU P9K52A) | |
| HPE M12 48U 600mm G2 Rack 208-230V Top Feed Rear Door Heat Exchanger | S4N09A |
| HPE M14 48U 600mm G2 Rack 208-230V Top Feed Rear Door Heat Exchanger | S4N10A |
| HPE M12 48U 600mm G2 Rack 208-230V Bottom Feed Rear Door Heat Exchanger | S4N11A |
| HPE M14 48U 600mm G2 Rack 208-230V Bottom Feed Rear Door Heat Exchanger | S4N12A |
| HPE M14 48U 600mm G2 Rack 260-290V Top Feed Rear Door Heat Exchanger | S4N13A |
| HPE M14 48U 600mm G2 Rack 260-290V Bottom Feed Rear Door Heat Exchanger | S4N14A |
| For 48U 800mm HPE G2 Racks (Rack SKU P9K58A) | |
| HPE M12 48U 800mm G2 Rack 208-230V Top Feed Rear Door Heat Exchanger | S4N15A |
| HPE M14 48U 800mm G2 Rack 208-230V Top Feed Rear Door Heat Exchanger | S4N16A |
| HPE M12 48U 800mm G2 Rack 208-230V Bottom Feed Rear Door Heat Exchanger | S4N17A |
| HPE M14 48U 800mm G2 Rack 208-230V Bottom Feed Rear Door Heat Exchanger | S4N18A |
| HPE M14 48U 800mm G2 Rack 260-290V Top Feed Rear Door Heat Exchanger | S4N19A |
| HPE M14 48U 800mm G2 Rack 260-290V Bottom Feed Rear Door Heat Exchanger | S4N20A |
| Hose Kits for RDHX | |
| HPE QD to TC 1.8m Hose Pair for Liquid Cooled Door | R4N58A |
| HPE QD to TC 2.4m Hose Pair for Liquid Cooled Door | R4N59A |
| HPE QD to TC 3m Hose Pair for Liquid Cooled Door | R4N60A |
| HPE QD to TC 3.7m Hose Pair for Liquid Cooled Door | R4N61A |
| HPE QD to TC 4.3m Hose Pair for Liquid Cooled Door | R4N62A |
| USA Facility Adapter for RDHX (Only Sites That Require NPT Thread) | |
| HPE Cray Supercomputing 25.4mm H2O Adapter NPT Assembly | R6W44A |
| International Facility Adapter for RDHX (Only International Sites That Require BSPT Thread) | |
| HPE Cray Supercomputer 25.4mm Water Adapter BSPT Assembly | S0B09|A |
| Notes: Need 1 Hose Kit SKU and 1 Facility Adapter SKU per door that is on order. | |
| 270kW CDU for RDHX - USA Voltage | |
| HPE Cray Supercomputer 3-phase 270kW 208V 60Hz 63.5mm NA Floor Coolant Distribution Unit | R4N53A |
| HPE Cray Supercomputer 3-phase 270kW 480V 60Hz 63.5mm NA Floor Coolant Distribution Unit | R4N56A |
| 270kW CDU for RDHX - EU Voltage CDU for RDHX | |
| HPE Cray Supercomputer 3-phase 270kW 400V 50Hz 63.5mm EU Floor Coolant Distribution Unit | R9B19A |
| USA Facility Adapter RDHX CDU | |
| HPE Cray Supercomputing 76.2mm H2O Adapter NPT Assembly | R6T83A |
| International Facility Adapter for RDHX CDU (Only International Sites That Require BSPT Thread) | |
| HPE Cray Supercomputer 76.2mm Water Adapter BSPT Assembly | S0B12A |
| Notes: – Need 1 Facility Adapter SKU (R6T83A or S0B12A) per CDU on order. – A CDU is required for sites that have supply water temperature at or below dew point. – The CDUs include a primary hose kit, secondary manifold, and treated water for the secondary cooling loop to the RDHX’s. – HPE provided secondary manifold is designed for raised floor data centers. If the data center is on a concrete slab, the customer is required to provide the overhead secondary manifold that feeds from the CDU to the RDHX’s. – Consult with Site Engineering when planning to use or don’t know if you will need to use a CDU. | |
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HPE Services Operational services
No matter where you are in your transformation journey, you can count on HPE Services to deliver the expertise you need when, where, and how you need it. From planning to deployment, ongoing operations and beyond, our experts can help you realize your digital ambitions.
HPE Complete Care Service
HPE Complete Care Service is a modular, edge-to-cloud IT environment service designed to help optimize your entire IT environment and achieve agreed upon IT outcomes and business goals through a personalized experience. All delivered by an assigned team of HPE Services experts. HPE Complete Care Service provides:
- − A complete coverage approach – solution support with end-to-end case resolution
- − An assigned HPE support team
- − Modular and fully personalized engagement
- − Enhanced Incident Management experience with direct access to HPC experts
- − Digitally enabled and AI driven customer experience
https://www.hpe.com/services/completecare
HPE Tech Care Service
HPE Tech Care Service is the operational support service experience for HPE products. The service goes beyond traditional support by providing access to product specific experts, an AI driven digital experience, and general technical guidance to not only reduce risk but constantly search for ways to do things better. HPE Tech Care Service delivers a customer-centric, AI driven, and digitally enabled customer experience to move your business forward. HPE Tech Care Service is available in three response levels. Basic, which provides 9x5 business hour availability and a 2-hour response time. Essential which provides a 15-minute response time 24x7 for most enterprise level customers, and Critical which includes a 6-hour repair commitment where available and outage management response for severity 1 incidents.
Service and Installation SKUsInstallation SKU and Band number for RDHXs: HA114A1#V16 | ||
| Installation SKU and Band numbers for CDUs | Hardware SKU | Installation SKU & Band Number |
| HPE Cray SC 270kW 208V 60Hz NA Floor CDU | R4N53A | HA114A1#V17 |
| HPE Cray SC 270kW 480V 60Hz NA Floor CDU | R4N56A | HA114A1#V17 |
| HPE Cray SC 270kW 400V 50Hz EU Floor CDU | R9B19A | HA114A1#V17 |
| Support Band number for RDHXs and CDUs | Hardware SKU | Support Band Number |
| Default RDHX | - | ZNK |
| HPE M14 42U 600 G2 208-230V TF RDHX | R4M12A | Z85 |
| HPE Cray SC 48Ux600x1200 AR3307 Rack | R4M95A | ZNL |
| HPE Cray SC 270kW 208V 60Hz NA Floor CDU | R4N53A | ZNM |
| Upfront Support SKUs | |
| HPE 3Y Tech Care Basic Service | HU4B2A3 |
| HPE 4Y Tech Care Basic Service | HU4B2A4 |
| HPE 5Y Tech Care Basic Service | HU4B2A5 |
| HPE 3Y Tech Care Basic with Defective Media Retention Service | HU4B3A3 |
| HPE 4Y Tech Care Basic with Defective Media Retention Service | HU4B3A4 |
| HPE 5Y Tech Care Basic with Defective Media Retention Service | HU4B3A5 |
| HPE 3Y Tech Care Essential Service | HU4A6A3 |
| HPE 4Y Tech Care Essential Service | HU4A6A4 |
| HPE 5Y Tech Care Essential Service | HU4A6A5 |
| HPE 3Y Tech Care Essential with Defective Media Retention Service | HU4A7A3 |
| HPE 4Y Tech Care Essential with Defective Media Retention Service | HU4A7A4 |
| HPE 5Y Tech Care Essential with Defective Media Retention Service | HU4A7A5 |
| HPE 3Y Complete Care Addon Basic Service | HU4D8A3 |
| HPE 4Y Complete Care Addon Basic Service | HU4D8A4 |
| HPE 5Y Complete Care Addon Basic Service | HU4D8A5 |
| HPE 3Y Complete Care Addon Basic with Defective Media Retention Service | HU4D9A3 |
| HPE 4Y Complete Care Addon Basic with Defective Media Retention Service | HU4D9A4 |
| HPE 5Y Complete Care Addon Basic with Defective Media Retention Service | HU4D9A5 |
| HPE 3Y Complete Care Addon Essential Service | HU4D5A3 |
| HPE 4Y Complete Care Addon Essential Service | HU4D5A4 |
| HPE 5Y Complete Care Addon Essential Service | HU4D5A5 |
| HPE 3Y Complete Care Addon Essential with Defective Media Retention Service | HU4D6A3 |
| HPE 4Y Complete Care Addon Essential with Defective Media Retention Service | HU4D6A4 |
| HPE 5Y Complete Care Addon Essential with Defective Media Retention Service | HU4D6A5 |
| Notes: – Example of building a Support SKU for a HW SKU: – 5Y Tech Care Essential for R4M12A = HU4A6A5#Z85 – Learn more about HPE Tech Care – Learn more about HPE Complete Care | |
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a00039574enw, 16140 - Worldwide - V3 - 02-February-2026