by Ann Withanee — February 25, 2011—ASHRAE continues to widen the temperature and humidity ranges for servers through a soon-to-be-published third edition of the datacom book, Thermal Guidelines for Data Processing Environments.
The first edition was published in 2004 and created the first global, vendor neutral environmental specification for data centers, according to ASHRAE. Prior to its publication, data center temperature requirements were set individually by each equipment manufacturer. This typically resulted in using the most stringent temperature plus a safety factor being used across the entirety of the data center.
The second edition (2008) took considerable deliberation among the manufacturers and raised the recommended upper limit to 81 F (27 C).
The third edition will enable compressorless cooling (all cooling through economizers) in many applications. Accomplishing this has been a challenge since major tradeoffs (equipment size, equipment cost and operating cost) surface above a certain temperature threshold. This challenge is complicated because the threshold is not the same for all the manufacturers.
For more information, see the ASHRAE Web site.
