As the summer heat manifests its hold on the northern hemisphere and the temperatures rise, many data centers will test the limits of their cooling systems and in some cases also hope that the IT equipment can in fact operate at the upper boundaries of the 2011 ASHRAE Expanded Thermal Guidelines.
Of course, when we think of the ASHARE charts we instinctively assume that we are discussing air cooled IT equipment. The latest edition of the thermal guidelines, which based on the consensus of the TC 9.9 committee, made it clear that modern IT equipment is much more tolerant of broader environmental conditions. While the “recommended” range remained unchanged at 64.4°F to 80.6°F (18°C to 27°C), it is the A2 “allowable” range of 50°F to 95°F, which represents the majority of IT hardware (except tape drives), which provides greater opportunity to save cooling system energy. This can be done by most existing cooling systems by simply raising the supply temperatures slowly or for new installations by incorporating free cooling in the design.