Engineering Designer Guide

WP-5: Essential Cooling System Requirements for Next Generation Data Centers Effective mission critical installations must address the known problems and challenges relating to current and past data center designs. This paper presents a categorized and prioritized collection of cooling system challenges and requirements as obtained through systematic user interviews.
English PDF (rev. 3)  
WP-6: Determining Total Cost of Ownership for Data Center and Network Room Infrastructure An improved method for measuring Total Cost of Ownership of data center and network room physical infrastructure and relating these costs to the overall Information Technology infrastructure is described, with examples. The cost drivers of TCO are quantified. The largest cost driver is shown to be unnecessary unabsorbed costs resulting from the oversizing of the infrastructure.
English PDF (rev. 3)  
WP-25: Calculating Total Cooling Requirements for Data Centers This document describes how to estimate heat output from Information Technology equipment and other devices in a data center such as UPS, for purposes of sizing air conditioning systems. A number of common conversion factors and design guideline values are also included.
English PDF (rev. 2)  
WP-40: Cooling Audit for Identifying Potential Cooling Problems in Data Centers The compaction of Information Technology equipment and simultaneous increases in processor power consumption are creating challenges for data center managers in ensuring adequate distribution of cool air, removal of hot air and sufficient cooling capacity. This paper provides a checklist for assessing potential problems that can adversely affect the cooling environment within a data center.
English PDF (rev. 2)  
WP-44: Improving Rack Cooling Performance Using Airflow Management Blanking Panels Unused vertical space in open frame racks and rack enclosures creates an unrestricted recycling of hot air that causes equipment to heat up unnecessarily. The use of airflow management blanking panels can reduce this problem. This paper explains and quantifies the effects of airflow management blanking panels on cooling system performance.
English PDF (rev. 3)  
WP-46: Cooling Strategies for Ultra-High Density Racks and Blade Servers Rack power of 10 kW per rack or more can result from the deployment of high density information technology equipment such as blade servers. This creates difficult cooling challenges in a data center environment where the industry average rack power consumption is under 2 kW. Five strategies for deploying ultra-high power racks are described, covering practical solutions for both new and existing data centers.
English PDF (rev. 5)  
WP-49: Avoidable Mistakes that Compromise Cooling Performance in Data Centers and Network Rooms Avoidable mistakes that are routinely made when installing cooling systems and racks in data centers or network rooms compromise availability and increase costs. These unintentional flaws create hot-spots, decrease fault tolerance, decrease efficiency, and reduce cooling capacity. Although facilities operators are often held accountable for cooling problems, many problems are actually caused by improper deployment of IT equipment outside of their control. This paper examines these typical mistakes, explains their principles, quantifies their impacts, and describes simple remedies.
English PDF (rev. 1)  
WP-50: Cooling Solutions for Rack Equipment with Side-to-Side Airflow Equipment with side-to-side airflow presents special cooling challenges in the modern data center. Common rack enclosures and rack layouts are fundamentally incompatible with side-to-side cooling, resulting in equipment that receives supply air of excessive temperature. This paper describes the problem along with several side-effects that are not generally appreciated. Various solutions to the problem are described along with their costs and benefits.
English PDF (rev. 0)  
WP-55: Air Distribution Architecture Options for Mission Critical Facilities There are nine basic ways to use air to cool equipment in data centers and network rooms. These methods vary in performance, cost, and ease of implementation. These methods are described along with their various advantages. The proper application of these cooling techniques is essential knowledge for Information Systems personnel as well as Facilities Managers.
English PDF (rev. 1)  
WP-56: How and Why Mission-Critical Cooling Systems Differ From Common Air Conditioners Today's technology rooms require precise, stable environments in order for sensitive electronics to operate optimally. Standard comfort air conditioning is ill suited for technology rooms, leading to system shutdowns and component failures. Because precision air conditioning maintains temperature and humidity within a very narrow range, it provides the environmental stability required by sensitive electronic equipment, allowing your business to avoid expensive downtime.
English PDF (rev. 2)  
WP-58: Humidification Strategies for Data Centers and Network Rooms The control of humidity in Information Technology environments is essential to achieving high availability. This paper explains how humidity affects equipment and why humidity control is required. Quantitative design guidelines for existing and new computing installations are discussed. Alternative methods to achieve desired humidity are described and contrasted. The difficult issue of how and where humidity should be measured is explained. The hidden costs associated with over-humidification are described.
English PDF (rev. 1)  
WP-59: The Different Types of Air Conditioning Equipment for IT Environments Cooling equipment for an IT environment can be implemented in 10 basic configurations. The selection of the appropriate configuration for a particular installation is affected by the existing facility infrastructure, the total power level of the installation, the geographical location, and the physical constraints of the building. This document describes the 5 fundamental cooling transport methods that combine with 2 fundamental physical arrangements to give rise to the 10 basic configurations. A method for selection of the appropriate configuration for a particular installation is described. The information in this paper allows IT professionals to be more involved in the specification of precision cooling solutions that better align with IT objectives.
English PDF (rev. 0)  
WP-68: Cooling Strategies for IT Wiring Closets and Small Rooms Cooling for IT wiring closets is rarely planned and typically only implemented after failures or overheating occur. Historically, no clear standard exists for specifying sufficient cooling to achieve predictable behavior within wiring closets. An appropriate specification for cooling IT wiring closets should assure compatibility with anticipated loads, provide unambiguous instruction for design and installation of cooling equipment, prevent oversizing, maximize electrical efficiency, and be flexible enough to work in various shapes and types of closets. This paper describes the science and practical application of an improved method for the specification of cooling for wiring closets.
English PDF (rev. 0)  
WP-69: Power and Cooling for VoIP and IP Telephony Applications Voice Over IP (VoIP) deployments can cause unexpected or unplanned power and cooling requirements in wiring closets and wiring rooms. Most wiring closets do not have uninterruptible power available, and they do not provide the ventilation or cooling required to prevent equipment overheating. Understanding the unique cooling and powering needs of VoIP equipment allows planning for a successful and cost effective VoIP deployment. This paper explains how to plan for VoIP power and cooling needs, and describes simple, fast, reliable, and cost effective strategies for upgrading old facilities and building new facilities.
English PDF (rev. 0)  
WP-121: Airflow Uniformity Through Perforated Tiles in a Raised-Floor Data Center Perforated tiles on a raised floor often deliver substantially more or less airflow than expected, resulting in inefficiencies and even equipment failure due to inadequate cooling. In this paper, the impact of data center design parameters on perforated tile airflow is quantified and methods of improving the uniformity are discussed. This paper was written jointly by APC and IBM for the ASME InterPACK2005 Conference, held July 17-22 in San Francisco, California, USA. It is taken directly from the conference proceedings in its original form.
English PDF (rev. 0)  
WP-123: Impact of High Density Hot Aisles on IT Personnel Work Conditions The use of modern enclosed hot aisles to address increasing power densities in the data center has brought into question the suitability of working conditions in these hot aisle environments. In this paper, it is determined that the additional heat stress imposed by such high density IT environments is of minimal concern.
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WP-125: Strategies for Deploying Blade Servers in Existing Data Centers When blade servers are densely packed, they can exceed the power and cooling capacities of almost all traditional data centers. This paper explains how to evaluate the options and select the best power and cooling approach for a successful and predictable blade deployment.
English PDF (rev. 1)  
WP-130: The Advantages of Row and Rack-Oriented Cooling Architectures for Data Centers Room cooling is an ineffective approach for next-generation data centers. Latest generation high density and variable density IT equipment create conditions that room cooling was never intended to address, resulting in cooling systems that are inefficient, unpredictable, and low in power density. Row-oriented and rack-oriented cooling architectures have been developed to address these problems. This paper contrasts room, row, and rack architectures and shows why row-oriented cooling will emerge as the preferred solution for most next generation data centers.
English PDF (rev. 0)  
WP-131: Improved Chilled Water Piping Distribution Methodology for Data Centers Chilled water remains a popular cooling medium; however leaks in the piping systems are a threat to system availability. High density computing creates the need to bring chilled water closer than ever before to the IT equipment, prompting the need for new high reliability piping methods. This paper discusses new piping approaches which can dramatically reduce the risk of leakage and facilitate high density deployment. Alternative piping approaches and the advantages over traditional piping systems are described.
English PDF (rev. 0)