Frequently Asked Questions about the
Do you have any installations where Data Center heat is reclaimed?
We have installations where return water from CRAC units is fed into the RDHx before returning to the chiller.
Are there published case studies about your system efficiency?
A 2008 case study by the Silicon Valley Leadership Group discusses the performance and efficiency of the RDHx along with other leading modular liquid cooling solutions. This study demonstrated a 10X improvement in efficiency using Coolcentric RDHx vs. air cooling, and a 3X improvement in efficiency comparing Coolcentric to next-in-class solutions. A second case study in 2010 confirmed the superior effeciency of passive rear door cooling.
Is Coolcentric's system EU RoHS compliant?
The RDHx is EU RoHS compliant. The Hoses Kits and CDU are not currently compliant, they are likely exempt from the regulations however a final determination has not been made at this time.
What energy savings will Coolcentric's solutions provide?
By reducing the amount of conventional perimeter cooling required and allowing for warmer chilled water temperatures, Coolcentric solutions delivers as much as 60% total cooling energy savings. Energy savings within the data center itself can approach 90% when compared to indoor cooling units.
Have the manufacturers of the Data Center Equipment approved the use of your system with their equipment? If so which manufacturers?
We have known deployments with equipment from Appro, Cisco, Dell, EMC, Fujitsu, HP, IBM, Penguin, Sun; we have active engagements with approximately 20 additional OEMs. Because of the extensive global install base, the variety of equipment covered is extremely diverse.
Does Coolcentric's system balance each RDHx for rack heat load? What do you do if you have localized high density racks within a Data Center area?
For simplicity and maximum reliability RDHx itself does not have a mechanism to balance water flows; this would be handled by the distribution system. The CDU has optional flow regulators that can be manually adjusted. Specific high density racks either have increased water delivered to them or any heat not treated by the RDHx will be captured and cooled by adjacent RDHx units.
Is Coolcentric's system China RoHS compliant?
Compliance to China RoHS requirements has not been fully investigated at this time. Our products are likely exempt from the regulations however a final determination has not been made yet. Coolcentric's system works at 2°C over dew point.
Where is the monitoring take place and how many points of monitoring is required?
The CDU has a temperature/ humidity sensor on board to measure the dew point. Only a single sensor is needed since dew point is consistent throughout a data center even if the temperature and humidity varies. A remote mounting option is available.
What are Coolcentric's system optimal settings?
Optimal settings for the RDHx are anywhere in the “neutral zone”. In addition, to maximize the secondary loop efficiency the CDU should be operating as close to 100% load as possible. What are typical system liquid volumes for the secondary loop? A system with (1) rack-mount CDU, (1) RDHx and (1) 10’ hose kit contains approximately 3 gallons (~11 liters). Floor-mount CDU system with internal manifold, (6) RDHx and (6) 50’ hose kits contains approximately 32 gallons (122 liters)
What materials are the secondary loop wetted components made of?
The secondary loop components are made from both metallic and non-metallic materials. A standard system contains: copper, brass and stainless steel; all of which are protected from corrosion by Coolcentric's treated water solution. Non-metallic components are made from EPDM rubber, polypropylene, polyacetal and PVC.
What type of system installation would you recommend for large (multi-MW) data centers?
Large data center deployments are often recommended to employ a centralized water distribution system to supply above dew point water to the RDHx. "Above dew point" is also referred to as "non-condensing", this ensures that no condensate forms on the coil and eliminates the need to manage condensate (via pumps and drains). Contact Coolcentric to determine what solution best suits your requirements
Will the use of RDHx’s in a Data Center that still uses CRAC’s result in cooler return air to the CRAC’s which reduces their efficiency?
CRAC units are active devices so they adjust with the changing conditions. When the return air temperature is reduced after the deployment of RDHx the units will respond by adjusting the chilled water valve and reducing the flow of water through valve and hence the capacity; if the unit is equipped with VFDs then the fans will slow down also in proportion to the valve position. Because of these responses the individual CRAC efficiency does not drop. If the CRAC units are so lightly loaded that they are rarely actually cooling then they can be shut off entirely. When looking at the overall data center cooling system the same load is being cooled but less energy is being expended, so in fact the overall efficiency is going up.