Humidity is a frequent topic of conversation this time of year in Kele’s neck of the woods. While the more technically informed meticulously monitor and delineate between relative humidity and dew point for a true gauge of the moisture (i.e., sweat) factor, the end result is certain. August humidity in the Mid-South can be oppressive, drenching, and push many to surrender to a little “downtime.” The same can happen in your data center any time of year, but downtime? Not an option.
Earlier this year, we wrote about strategies to keep your data center cool. Maintaining humidity in the recommended range is equally important. The American Society of Heating, Refrigerating and Air-Conditioning Engineers 2016 guidelines indicate a range of 20% to 80% relative humidity with a recommendation of around 50%.
Too much humidity in your data increases the risk of condensation. Moisture on your data center equipment can lead to damage, corrosion, and possibly equipment failure.
Generally speaking, relative humidity represents the amount of water vapor the air is holding as a percentage of what it would be holding if it were wet. (50% relative humidity means the air is holding 50% of water vapor it can hold at the current temperature.) Increasing the temperature increases the amount of vapor the air can hold before condensation begins. However, as we discussed, too much heat in a data center is also problematic.
A phrase not in the Mid-South vernacular— “too little humidity”—can also cause potentially catastrophic issues in a data center. If the air becomes too dry, the risk of an electrostatic discharge (ESD) increases. An ESD can generate enough heat to damage small electronic parts, and the high voltage for the discharge can damage other delicate components.
Monitoring humidity critical. Ensuring the ambient air is flowing how and when it should to maintain the appropriate relative humidity is the key. Refer to our diagram for where duct humidity sensors are typically located in an air handling unit. Kele has a broad selection of duct humidity sensors from several reputable supplier partners. Our project and technical services teams will help you think through your entire air handler system on the front end and select the right components, including humidity sensors.