PTS understands the effect air conditioning and air distribution has on the performance and availability of information technology (IT) equipment and IT service delivery. Computer rooms are a component of the overall data center environment. Their purpose is to shelter network and server infrastructure as well as their related cabling, otherwise known as the computer rooms critical load. Our experts can recommend the best computer room air conditioning (CRAC) configuration for your computer room. Our solutions provide increased cooling system availability, minimized operational costs, and protection from equipment downtime and/or damage.
PTS can design and implement a variety of computer room air conditioning configurations to solve a variety of computer room heat load conditions. All of our configurations work to displace heat from the computer room. However, there are many factors that contribute toward selecting the most suitable configuration for any particular computer room. These include ceiling height, access floor depth, equipment layout, and heat load, just to name a few. Additionally, there are various computer room air conditioner equipment types including portable units, ceiling-mounted units, and floor-mounted units, not to mention, precision air conditioners versus comfort-cool air conditioners. Further complicating the issue, heat rejection can be accomplished via self-contained systems or split-systems. Finally, cooling can be accomplished using air-cooled, glycol-cooled, water-cooled, or chilled water methods. Each has its own advantages and disadvantages.
There are a variety of air conditioning systems on the market that are specifically designed for computer room applications. They are known as precision air conditioners. They are considered precision because they control the computer room temperature to within one degree of its set point as well as the ambient humidity.
The most common computer room cooling system is a two-piece system, often referred to as a, splitsystem. It is composed of two sections. In an air-cooled system, it includes an evaporator section, where the cold air is supplied from, and a condenser section, where the heat is rejected from. This system is known as a DX (direct expansion) system due to its use of a compressor as part of the refrigeration cycle. Refrigerant lines connect the computer room refrigeration unit to the outdoor, air-cooled, condenser unit. Conversely, in a self-contained system, these components are combined into a single system, located inside the computer room. The exhaust air is rejected above the computer room ceiling or within the confines of the surrounding spaces.
Glycol-cooled air conditioning systems cool in much the same way. Glycol flows through the heat exchanger moving the absorbed heat to an outdoor-mounted fluid-cooler, also known as a dry-cooler. The pipes are then cooled by strong fans. The advantage of this system is that the absorbed heat can be pumped much further than in an air-cooled system. However, the cost to implement this system is greater.
Less common, is a water-cooled system. Here, condenser water replaces the glycol and transports heat to an external cooling tower instead of to a fluid cooler. The advantage of this approach is that water can absorb more heat than either refrigerant or glycol. The downside is that water must be introduced inside the computer room and is much more difficult to pump.
In a chilled water system, the refrigeration process is relocated from a computer room air conditioner to a water chiller. The liquid is cooled to approximately 46-degrees Fahrenheit (8-degrees Celsius) and pumped to indoor air handlers. Warm air circulates over the chilled coils. The absorbed heat is transported to the chiller and rejected via the condenser water loop. This system is most commonly found in larger computer rooms due to its high installation cost.
Very often, extensive duct-work and/or raised floor delivery systems are required with any of these computer room air conditioner configurations. Many design factors influence the type of air conditioning setup a computer room requires. PTS can help you choose the right cooling system for your needs.
To learn more about PTS’ Computer Room Design services and how they can help you meet your Mission Critical Facility Requirements, contact us or visit: