ColdLogik Passive RDC Range

ColdLogik Smart Passive is designed with sustainability in mind, allowing you to plan for the future without discarding a proven energy efficient solution of today. This has been achieved by providing a unique upgrade path from a self cooling passive RDC as long as the correct static pressure is available, to a proactively cooled RDC capable of fully controlling both the environment within the cabinet and the room temperature itself.

cl20 passive range2

Anticipating the next generation computer chip sets, heat load densities are set to rise in the next few years—this will have major ramifications on the decisions you make today in designing your data center with an upgrade path allowing for such higher density equipment.

Smart Passive 42U x 600w door

Capable of a potential 39kW of ‘passive’ cooling relying on the fans in the active equipment within the cabinet to produce the airflow to the coil.

Smart Passive 48U x 600w door

Capable of a potential 41kW of ‘passive’ cooling relying on the fans in the active equipment within the cabinet to produce the airflow to the coil.

Smart Passive 42U x 800w door

Capable of a potential 43kW of ‘passive’ cooling relying on the fans in the active equipment within the cabinet to produce the airflow to the coil.

Smart Passive 48U x 800w door

Capable of a potential 45kW of ‘passive’ cooling relying on the fans in the active equipment within the cabinet to produce the airflow to the coil.

Upgrade path

Passive Upgrade

From passive to proactive

The upgrade path has been designed to enable a smooth transition from passive to proactive. This is achieved by removing the passive front grille and replacing with the proactive module which would initially contain three variable speed EC fans which ramp up and down together in order to provide a reliable airflow across all sections of the cabinet

Thermistors are positioned within the cabinet which are controlled by the introduction of the ColdLogik Management System and the system is ready to run.

At this point there is also the option to add in an additional two way valve to more accurately control the water flow and therefore the returning air to the room ambient, the CMS has capacity for the specific valve operation included as standard. The addition of such a two way valve can greatly increase the efficiency of inverter driven pumps on site by reducing the volumetric load required through the coil and still maintaining the desired room ambient temperature.

The further two upgrades consist of single fan upgrades (totalling five). This allows for an improved duty that is available from the door whilst still maintaining the room temperature required. When these additional fans are added they also become part of the centrally controlled bank and will respond with all other fans to ensure smooth performance and maximum efficiency.

Step 1
cl20 passive step1
Remove vent panel and top cover.
Step 2
cl20 passive step2
Fit fan panel, ColdLogik Management System, fan panels and fan cover.


A uniquely modular upgradable ‘passive to proactive’ rear door cooler

cl20 passive step1
Zero running costs
  • No electrical components, relies on the fans of the active equipment for cooling
Easy installation
  • Hang RDC directly to the cabinet via interface frame and then it only requires water connection to complete installation
Lower capital cost
  • No fans, no controller or monitoring simply the rear door and coil
Silent running
  • No external fans when running as passive model
Condensate free operation

Condensate free operation is based on sensible cooling which operates at ‘dew point’. This prevents condensate from forming while ensuring a more efficient operation of the external equipment.

How it works

CL20 rear of cabinet passive cooler, relies solely upon the active equipment fans producing enough air volume to in effect 'self cool'

CL20passive How it works

How a passive RDC works

Ambient air is pulled into the cabinet via the active equipment fans. The hot exhaust air produced by the active equipment then passes over a heat exchanger matrix by its own velocity, heat is then transferred and rejected to coolant. The resulting chilled air then passes back into the room.


Cooling distribution unit and leak prevention system

Another unique and important attribute of the ColdLogik solution is the option of a patented Leak Prevention System (LPS), which is incorporated within the Cooling Distribution Unit 'CDU'. As water is present in most data centers, they have the same inherent weaknesses – such as leak detection systems shutting down parts of the cooling system when moisture is detected. In the event of a pipework breach, the LPS – Leak Prevention System – stops water escaping from the pipework and allows the cooling system to continue running unimpaired, providing uptime, safety and system resilience

Cooling Tower Fan ARM

External cooling options

External cooling selection is less restrictive with a ColdLogik system – in many cases you do not have to rely on traditional mechanical cooling products such as chillers. This is primarily due to the design and control functions of the CL20 rear coolers – the rear coolers utilise much higher water supply temperatures compared to other forms of computer room air-conditioning to achieve the same room ambient temperature. Consequentially, free cooling can be obtained from a wider range of options such as river, lakes or boreholes. When all the facts are taken into account, our bold claim of 93% energy savings over and above standard computer room aircon systems is easily justified.

Smart Passive deployment strategies

OEM Retrofit

Passive Frame

Deployment strategies

One of the biggest advantages of the Smart Passive Rear Door Cooler is its ability attach to a USystems cabinet or another manufacturers cabinet via an interface frame.

The interface frame is a universal product, so all standard and some nonstandard enclosures can be accommodated. It allows a secure fixing of the rear cooler without transferring any additional weight to the existing cabinet.

The frame brings many of the benefits of the CL20 cooler family without the need to decommission old cabinets – or even entire data centers.

NB. Standard recognisable manufacturers racks can be accommodated without feet, castors or plinths. If these are used, a CAD step file would be required of the rack to enable us to design a made to order interface frame.

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