CarnotJet™ FAQs:
What is the capacity in U of the CarnotJet™?
How much does CarnotJet™ weigh?
How much space does CarnotJet™ require?
What is included with my order?
How should my facility prepare for installation?
How long until my system is up and running?
What are CarnotJet’s™ maintenance needs/coolant replacement?
Does GRC provide training?
How does the evaluation program work?
What server modifications are required before installation?
Are there special regulations for CarnotJet™ systems?
Are there specific fire regulations?
Where does all the heat go?
How hot/cold does it have to be to run CarnotJet™?
What does secondary containment look like?
What type of servers and storage can be used?
What else can be installed in CarnotJet™ beside servers?
Where can I find pricing/ordering information?
What about fiber optics?
Q: What is the capacity in U of each rack?
A: Rack capacity can be customer specified. Currently, we have 10U & 13U models for evaluation and 42U & 60U standard models. We’re happy to build to any specifications provided by the customer.
Q: How much does CarnotJet™ weigh?
A: Each rack, fully loaded with coolant and servers, weighs about 3,300 lbs, or 250 lbs/square foot. The tank and coolant alone weigh about 1900 lbs, or 150 lbs/square foot. The fully-loaded number is roughly equivalent to an air-cooled rack.
Q: How much space does CarnotJet™ use?
A: Each rack requires about 13 square feet of space. Including the rack, secondary containment, walkway, and pump module, a four-rack system will require a total of 25-35 square feet.
Q: What is included with my order?
A: We price everything together: pump, power cords, coolant, and server modification. Extras include secondary containment, which is included with evaluation units but not with larger installs, and the final heat exchanger.
Q: What is required on my side? How should my facility prepare for installation?
A: GRC’s CarnotJet™ has four requisites for installation:
- Level surface. A level concrete floor is a simple and effective option.
- Heat Rejection Path: Several options are available, including: coolant-to-air radiator, evaporative cooling tower, and cold water loop. See Installation for more details.
- Secondary Containment: Useful for catching incidental spills or for emergency backup. For smaller installs, GRC includes modular secondary containment in the price.
- Power Cords: Our pump module will use a single or dual 120v or 208 single phase power feed. Different voltages can be used if specified during the order process.
Q: After I place an order, how long will it be until my system is up and running?
A: GRC will ship the units from our dock in 6-8 weeks. Once the system is on site and post customer pre-installation preperation, GRC engineers will typically take 2-10 days.
Q: What are CarnotJet’s™ maintenance needs?
A: The coolant does not need to be replaced over the life of the data center. However, if needed, coolant is available for less than $10 per gallon.
Occasional cleaning of the filter and strainer system that cleans the coolant is required, which does not require turning off the system.
A: We will provide all necessary operation and maintenance training during installation. We also offer a system manual that covers: server installation and removal, coolant-strainer maintenance, control system operation and set up, and other basic information.
Q: How does your evaluation program work?
A: GRC offers a 13U evaluation unit for a nominal fee. We ship with everything that is required to install a fully-functional trial system, including:
- One (1) 10U or 13U CarnotJet™ rack (about 4 square feet)
- One (1) fully-functional pump module (about 6 square feet)
- A 52-in. x 52-in. modular secondary containment pallet to to place the rack upon (no need to prep floor space)
- GreenDEF coolant
In addition to the servers you wish to install (and all accompanying power and Ethernet cables), we also require access to a 120-volt power cord to supply the pump module. GRC personnel will modify and install your servers so all the customer needs to do is provide power and Ethernet access.
Unlike full-scale units, the evaluation unit pump module does not require access to a heat exchanger such as cold air or cold water. Instead, the unit is self-contained and uses a radiator to expel hot air directly from the unit.
Q: What server modifications are required?
A: First, our technicians remove server fans and put them aside for future use or reverse-modification at a later date. Then, each hard drive is encapsulated using GRC’s proprietary hard drive sealing system. Finally, the CPU thermal grease is replaced with a non-soluble foil.
Q: Does CarnotJet™ have regulatory requirements?
A: Because our coolant is a mineral oil blend similar to one used for cosmetics, the only national regulatory requirements are about preventing spills into navigable waterways at large installations.
For installations greater than ~5 tanks (1,320 gallons) with a “reasonable expectation” of a discharge into a navigable waterway, the facility needs to have:
- Secondary containment to hold 110% of the largest container
- A written SPCC (Spill Prevention, Control and Countermeasure Plan), which can generally be self certified for facilities holding less than 10,000 gallons of coolant (~40 racks). GRC can help with this relatively simple process if the facility is near a waterway.
Regardless of installation size, GRC ensures that your facility has proper secondary containment to prevent slick floors. All evaluation units and single rack units come pre-supplied with modular secondary containment.
Q: What are the fire code requirements?
An International Building Code (IBC) and International Fire Code (IFC) review of our system by a Fire Protection Engineering & Code Consulting Firm determined that our GreenDEF coolant is Class IIIB with an NFPA-704 flammability rating of 1 on a scale of 4 (water = 0). Accordingly, CarnotJet™ does not require supplemental fire suppression systems beyond those utilized by most data centers.
More details are available upon request.
Q: Where does all the heat go?
A: Heat must be rejected to the outside in some form or fashion in all data centers, regardless of cooling method. We use several different methods of heat rejection, depending on the customer’s facility and preference:
- Coolant-to-air radiator.
- Evaporative cooling tower: no mechanical chilling, just water evaporation.
- Cold water loop: Reject heat to the waste line of a chilled water system.
Q: What temperature range does CarnotJet™ require?
A: CarnotJet™ will operate with an ambient temperature of -40 C to +100 C in the data center.
Q: What does secondary containment look like?
A: We typically choose one of two options, depending on the customer’s preference:
- Spill deck: modular secondary containment which can be installed in minutes and is easily adjusted and transported
- Berm system: lengths of catwalk metal are installed around the perimeter and allow for easy rack access
Q: What types of servers and storage can be used?
A: Almost any OEM server can be used.
Hard drives require encapsulation, solid state drives do not.
Q: What else can be installed in CarnotJet™ besides servers?
A: We currently have ethernet and Infiniband switches in service. Practically any electronic device will work, although ones with moving parts designed for air need pre-install preparation. Specifically, optical drives will not work.
Q: Where can I find pricing/ordering information?
A: Give us a call at (512) 692-8003 or e-mail us at [info@grcooling.com]. We’d love to hear from you.
The initial, favorable, results are in from fiber optic testing, with the detailed results available upon request. Tests were conducted with Cisco optical switches first in air, and then immersed in coolant, using UDP throughput performance tests and minimal interval ping floods. The tests showed no degradation in transfer times or error rate.