There is no simple answer to this, but I can make three suggestions:
- Have temperature and humidity monitors installed at key locations in the room, and possibly in high-density equipment cabinets as well. Properly locating the sensors requires some an experience. Major vendors may be able to help you with this better than consulting engineering firms.
- Have your HVAC installation/maintenance company ensure that your air conditioners are operating correctly, that the operating parameters ("set points") are set for optimum efficiency, and that units are not fighting one another (that is, one trying to humidify while the other is trying to de-humidify, or cool while the other is trying to heat, etc.). I'm assuming standard CRAC units here. Do NOT fiddle with the set points once they've been optimized. Change the password so no one can mess with them.
- If your sensors show cooling problems after the air conditioners are optimized, get a computer room audit from a firm that specializes in this work. (And just because a firm says they've designed data centers doesn't necessarily qualify them to do this. They may still be designing for ten years ago, and their results might not be any better than yours.)
This was first published in June 2005