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Coolant distribution units for liquid cooled GPU racks
A CDU sits between the loop that runs through your servers and the loop the building provides. It keeps the two apart and controls what the servers see. We can supply in-rack, in-row and liquid-to-air units, quoted with your GPU systems.
01
What it is
A coolant distribution unit keeps the loop that runs through the servers separate from the facility loop, and controls flow, temperature and filtration. Units come as in-rack, in-row or liquid-to-air.
The two loops are separated by a heat exchanger inside the unit, so building water never enters the servers. A liquid-to-air unit rejects heat into the room where there is no facility water.
02
Who it is for
- Any direct-to-chip deployment.
- Rack scale GPU systems, which are usually liquid cooled with a CDU in the rack or the row.
- AI training clusters, where dense racks usually need liquid at the chip with a CDU in the rack or row.
- Existing comms rooms, which often favour liquid-to-air CDUs because facility water is rare.
How it works
- 01
Two loops
The facility loop and the server loop are separated by a heat exchanger inside the unit, so building water never enters the servers.
- 02
Control
Pumps, valves and sensors manage flow, temperature and filtration on the server side.
- 03
Form factors
Units come as in-rack, in-row, or liquid-to-air, which rejects heat into the room where there is no facility water.
04
Where it fits
- Any direct-to-chip deployment.
- Rooms with facility water (in-rack or in-row units).
- Rooms without facility water (liquid-to-air units).
05
Things to check
- Facility water: temperature, flow and quality available.
- Space: a rack unit, a row position or floor space.
- Redundancy: how many units and pumps the design needs.
- Filtration, coolant specification and top up.
- Monitoring and alarms, and who responds to them.
06
What we can supply
- In-rack coolant distribution units.
- In-row coolant distribution units.
- Liquid-to-air coolant distribution units.
- Associated manifolds, hoses and fittings.
Specifications are provided with your quote, and datasheets are available on request. Stock and availability on application.
Related GPU systems. Rack scale GPU systems and multi GPU rack servers specified for liquid cooling.
Images are illustrative and do not show specific products.
How we work
Five steps, whether the request is for GPU systems, cooling, or both. Each enquiry carries a reference from receipt, and nothing is agreed until a written quote is accepted.
- 01
Scoping
We confirm workload, configuration, quantity and site constraints before anything else.
- 02
Configuration and validation
We check the bill of materials, power, cooling and interconnect fit before quoting, and check the system against the cooling and power you have or plan.
- 03
Sourcing
We source the configuration and confirm details in the written quote.
- 04
Compliance and checks
Sanctions, export control, end use and know your customer checks before any quote is final.
- 05
Logistics and delivery
We arrange delivery to your site and confirm the terms in writing.
08
Related questions
C04What does a CDU do?
A coolant distribution unit keeps the loop that runs through the servers separate from the facility loop, and controls flow, temperature and filtration. Units come as in-rack, in-row or liquid-to-air.
C01What is direct-to-chip cooling?
Metal cold plates sit on the GPUs and CPUs. Coolant flows through them, picks up the heat and carries it out of the server through manifolds in the rack to a coolant distribution unit.
C03Can liquid cooling be added to an existing room?
Often, yes. Rear door heat exchangers fit standard racks, and liquid-to-air CDUs reject heat into the room without facility water. Direct-to-chip with facility water usually needs pipework and a plan for the room.
C02Do GPU servers need liquid cooling?
Not always. Many configurations are available air cooled. Denser nodes and rack scale systems are increasingly designed for liquid, and some are only offered that way. It depends on the configuration; we confirm this in the quote.
Q14Can you quote GPU systems and cooling together?
Yes. That is the point of offering both. Choose "GPU systems and cooling" on the contact form, tell us about the site, and one written quote covers the systems and the cooling equipment. See Cooling.
Related pages
Liquid cooling
Direct-to-chip, CDUs and rear door heat exchangers, for dense racks.
Direct-to-chip liquid cooling
Cold plates on the hottest parts, with coolant carried through manifolds in the rack.
Rear door heat exchangers
A coil replaces the rack's rear door and takes the heat out of the air as it leaves.
GPU servers
GPU servers, rack scale GPU systems and PCIe GPUs.
Quote coolant distribution units with your GPU systems
One written quote can cover the systems and the cooling. Tell us about the site and we will scope both.