Phase One: Product Planning
Phase Two: Pre-Installation Preparation
Phase Three: Installation
Phase Four: System Monitoring and Maintenance
Phase One: Product Planning
How can we help your data center?
We know that fluid-submersion technology is relatively new to the data center market, so when you contact GR Cooling, we’re ready to answer your questions.
The first thing we do is learn about your data center and your cooling needs to customize a solution:
- What type of servers will you be cooling (e.g. 1U, blade, tray, GPU, etc)?
- How much density (kW load/rack) will you be adding?
- What types of heat rejection methods are available in your facility?
If you want to install blade servers, we can talk about the CarnotJet’s™ ability to handle high-density servers at minimal cost. If you’re limited by space or by electricity, we’ll tell you about the CarnotJet’s ability to support more computing power in less space while using less energy. If you’re facing a tight deadline, we can tell you about GR Cooling’s standard two-month build/ship/install timetable.
Because the CarnotJet™ easily integrates with existing infrastructure, we offer solutions that are custom-tailored to your facility. And the more we understand about your space and your needs, the more we can develop ways to incorporate our system into your data center with minimal headache and expense.
For example, the CarnotJet™ requires a final heat rejection method to cool down GreenDEF™ coolant as it runs through the pump module. What options are available in your facility to reject heat to the outside? Typical methods include:
- Evaporative cooling tower
- Existing chilled water loop: the CarnotJet™ is capable of using the return or hot leg to cool the hot GreenDEF™ coolant, increasing chiller efficiency
- Coolant-to-air radiator for small installations
What we offer:
Green Revolution Cooling currently offers 10U units for evaluation, and 42U and 60U CarnotJet™ systems for long-term single or multi-rack installations.
Generally speaking, our system pricing is based on a cost per Watt model, with costs scaling only modestly with server power density. Accordingly, unlike typical air-cooled systems, a very dense server rack achieves a lower price per Watt than a low density rack, enabling customers to use hardware they couldn’t previously, at a lower price.
The CarnotJet™ system is comprised of three main components:
- Rack (tank): Our Racks are available in a range of capacities (typically 42U) and resemble standard cabinets rotated ninety degrees on each axis (like a tub). A 42U Rack will handle up to 100kW of capacity.
- Pump Module: The Pump Module contains pumps, filters, and either a coolant-to-water heat exchanger or an optional coolant-to-air radiator for small installations. One Pump Module is used for 120kW of server power or around 4 Racks, using an air-cooled server as a benchmark. Pump Modules can be located in the data center periphery or under an existing raised floor.
- Control Module: Computer-controlled primary cooling loop, with sensor monitoring, logging, real-time diagnostics, and email and SNMP alerts. The control system carefully manages coolant flow and the fan or pump speed for the heat exchanger to ensure the cooling process is always energy efficient.
 A tank sized for 20kW can be upgraded to higher densities by changing out system pumps, heat exchangers, and updating control logic, while keeping the same Rack in place, to allow easy capacity upgrades.
 Note: 120kW of air-cooled servers equals roughly 100kW of servers in our solution because server fans are removed.
Phase Two: Pre-Installation Preparation
Once we receive an order, it takes 6-8 weeks to ship from our dock. When the system arrives on-site, GR Cooling engineers will typically take 2-10 days for system installation. During this time, GR Cooling Service Engineers will educate your staff on use and maintenance of the CarnotJet™ system.
Customer Preparation for installation:
The Customer provides CarnotJet’s™ five simple requisites for installation:
- Flat, Level Floor: CarnotJet’s™ racks require a level surface to ensure proper circulation. A level concrete floor is a simple and effective option.
- Heat Rejection Path: As is the case with all data centers, heat must be transferred outside of the facility. There are many alternatives that depend on size of installation, use of storage medium, climate, and existing infrastructure. With our evaluation units, the Pump Module does not require connection to an outdoor heat exchanger because the unit contains an integrated radiator.
- Secondary Containment: For catching incidental spills and for emergency backup. For evaluation units, GRC includes modular secondary containment. GRC offers secondary containment for larger installations as well.
- Power Feed: Our Pump Module will use a single or dual 120v or 208 single phase power feed. Different voltages can be used if specified upfront.
- Hard Drives: Customers typically ship server hard drives to GRC’s facility for encapsulation two to three weeks prior to installation. Server modifications are done at the customer’s site by GRC Service Engineers, although two of our customers have trained their technicians to do this themselves.
Preparing for CarnotJet™ is significantly less intensive than preparing for an air conditioned installation. There is no need to retrofit a space or install a raised floor. The CarnotJet’s™cooling capacity is completely pre-engineered and no computational fluid dynamics or other air-flow management is required.
Phase Three: Installation
After the system is built, the system is loaded onto pallets, shrink-wrapped, and sent to your location. GRC Service Engineers will arrive at your facility to begin the installation process.
Server Modification & Installation
While the CarnotJet system is being installed in your facility, we will also modify servers at the installation site. Having previously encapsulated server hard drives at GRC’s facility, our technicians now remove server fans (which are stored in case the server is ever reconverted to air use). Conventional thermal grease will dissolve, and so we replace it with a non-soluble thermal interface material solution, a Heat-Spring® by Indium Corp of America (link), which helps enable this technology. Solid State Drives do not require any modification.
PDUs mount to either the front or back of the Rack. Power cables then run into the Rack and down the sides to connect to the back of the server. Cables are organized via Cable Guides inside the Rack that segregate every 2U. Switches can be submerged in the Rack as well, and Ethernet cables run along a wiring duct attached to the back of the Rack.
Rack & Pump Module Installation
Our system generally uses one Pump Module for four Racks. Pump Modules can be installed anywhere near the Racks.
System installation begins with the secondary containment system. For evaluation units or smaller installations, we typically use modular secondary containment. For larger installations, we typically install a Berm around the perimeter of the system with an expanded-metal catwalk placed between the Racks as a non-slip platform.
Connect to Final Heat Exchanger and System Power On
Once our equipment is positioned, we install piping between each rack and the pump module, run a single electrical conduit between the Racks and Pump Module, and then connect the supply power to the Pump Module. We then use the Pump Module to fill the Rack with GreenDEF™ coolant. After a few diagnostic tests, the system is ready for servers.
We also strongly suggest connecting a ground strap between each Rack and corresponding PDU, in accordance with the electric code.
Server Decommissioning/ Server Lease Concerns
Some data centers lease their servers. To this end, we are happy to retrofit a server to “air-cooled” state by removing traces of coolant and re-installing all fans at the end of the lease period. Unfortunately, the encapsulation material cannot be removed from hard drives, but the encapsulated drives will still run well in an air-cooled environment.
Phase Four: System Use, Monitoring, and Maintenance
Removing a server for repair is simple. The coolant drains out of a server quickly as soon as it is removed from the rack and rested on the rails. The server is immediately available for all work. Please see our video under the Gallery Page for a visual demonstration.
Signature Technology Group (STG), our preferred server warranty provider, offers competitively priced warranty packages to support data center hardware used in our cooling system. STG offers the standard suite of server warranty and support options, including four-hour and next-day support and hardware repair.
Hard Drive Warranty
GR Cooling offers a two-year warranty on all new hard drives that have been encapsulated by GR Cooling.
System Warranty & Maintenance
GR Cooling includes a limited one-year parts & support warranty with each system. Additional years of support and warranty are available at a reasonable price. The coolant does not need to be replaced. The principle maintenance responsibility is to clean the strainer, which catches dust, stickers, and debris. The strainer can be bypassed to allow cleaning without turning the system off.
For the first year after installation, GR Cooling monitors your CarnotJet™ systems remotely 24 hours a day. We generate exception reports that include no-response errors, low fluid level warnings, changes in temperature, and more. After the first year, we offer continued remote monitoring for a nominal fee. The end user can easily integrate the CarnotJet™ alerts and status updates into their facilities management software.