Hot spots in a data center must be closely monitored: let the warmest areas in your facility get too warm and you risk degraded performance, outages, and potential equipment damage. Yet they can also drive how much you spend to cool your entire data center. The key is to find them, monitor them, and manage them.

One of the most contentious areas of data center operating cost reduction is cooling. There is an ongoing tension between lowering cooling costs and keeping facility temperatures within a deliberately conservative range. Many data centers accept higher cooling costs to avoid going outside the "comfort zone". Some avoid addressing cooling optimization based on a belief that the cost to implement doesn't have an acceptable payback -- costs too much and/or takes too long.

But optimizing data center cooling can be easier than you think.

Data center hot spots are a bit of an enigma. While they remain colorless and odorless, you know they're there. You can feel them as you walk by rows of humming server racks. We've all done it -- the hot spot drive-by. You feel it. It's kind of hot right here, isn't it?

Data center hot spots

It's unfortunate that some managers don't take hot spots seriously. Perhaps it is the covert and evasive nature of hot spots that place them on the back burner. Yet it only takes one negative thermal event to get management's attention.

Cooling represents one of the largest portions of data center energy usage -- 20-35% on average. Most data centers are overcooled with ambient temperatures kept at the lower end of ASHRAE guidelines.

ASHRAE 2011 Thermal Guidelines for Data Processing Environments

This is done to account for any possible condition that may be occurring in any rack at any time. This "abundance of caution" comes at a high energy cost and it creates an opportunity for substantial cost savings for many data centers.

Accurate information on rack-level temperature in your data center can help lower operating costs, avoid outages and meet SLA agreements. Packet Power's wireless Environmental Monitor makes getting that information easy. And it costs as much as 70% less than other solutions. 

Environmental monitoring and control in the data center is usually assumed to be synonymous with temperature control: how to make sure the air is at the optimal temperature at each place. Temperature, however, is only one of the two key parameters that determine the quality of air. Its twin, humidity, is much less understood.