Data Center Temperature
While increasing the overall operating temperature in a data center may provide cost savings from reduced energy usage for cooling, there may be unintended consequences on other infrastructure. Higher temperatures increase the rate of any chemical reaction, including corrosion rate, so an increase in operating temperature will accelerate corrosion in fire sprinkler piping. Simply stated, a higher data center temperature presents a greater risk of water leaks from the fire sprinkler system.
In 2008, ASHRAE (American Society of Heating, Refrigerating and Air-Conditioning Engineers) introduced the addendum Environmental Guidelines for Datacom Equipment, where they expanded the recommended operating temperature range from 20°C - 25°C (68°F - 77°F) to 18°C - 27°C (64°F - 81°F). To alleviate concerns, ASHRAE engineers mention that increasing operating temperature has little effect on hardware component temperatures, but should offer significant energy savings.
This increase, from a temperature range at the inlet temperature of server racks of only four degrees (77°F to 81°F) will also have an impact on the outlet temperatures since the delta-T (change in temperature) across the servers will remain the same. Therefore, the exhaust temperature - what is in the hot aisles and being returned to the cooling system - will be commensurately higher.
The Temperature Effect on Corrosion
The direct correlation between increased corrosion rates and higher temperatures is quantified by each 10°C/18°F increase in temperature doubling the rate of the corrosion reaction. ASHRAE originally recommended 20°C to 25°C, but a recent experiment by Intel went all the way to 33.3°C. Conversely, cooled sections of the data center are less likely to corrode due to slower corrosion rates. For instance, lower risk areas include under raised floors, in cold aisle contained areas, and above those areas.
The problem with the fire sprinkler industry relative to mission-critical data center installations is that there are currently no standards for fire sprinkler design and installation that take into effect the elevated risks associated with corrosion. Data centers carry a very disproportionate risk in two key areas: hardware risk and business continuity risk. Even a small leak in the fire sprinkler piping above a data hall can easily damage the water sensitive hardware stored and operating in the data hall.
Data center professionals cannot afford to ignore the risks that corrosion in fire sprinkler piping creates within their data halls. Standards must be developed and adopted for the design, installation, and maintenance of fire sprinkler systems in the mission-critical setting. Management of the risks associated with these systems must become an integral part of the uptime management process.
Fire Sprinkler System Corrosion
Corrosion in fire sprinkler systems is caused by the interaction of oxygen with the metal piping surface wherever liquid water is present. Dry pipe and preaction fire sprinkler systems make up the majority of fire sprinkler systems in data centers and mission critical facilities. Unfortunately, these systems are never truly "dry" and will corrode quite rapidly. Corrosion leads to water damage, plugging problems, reduced hydraulic performance, and reduced service life. The risks associated with corrosion in fire sprinkler systems include life safety risk, property risk, and business continuity risk.
Resources
- For more information about the risks associated with sprinkler pipe corrosion in the mission-critical environment visit our data center page.
- Learn more about the acute corrosion vulnerabilities of galvanized pipe, which is routinely used in the construction of preaction fire sprinkler systems protecting mission-critical data centers.
- Understand the basics of dry pipe nitrogen inerting (DPNI), which eliminates the systemic corrosion problems associated with fire sprinkler systems
