The challenge
A colocation data center needed to cut HVAC energy as rack densities rose. Supply-air pre-cooling with outdoor air risked humidity and contamination, so a plate (no moisture transfer) core was the only safe choice - rotary wheels are not used for data-center air because they can carry over contaminants.
The solution
Counter-flow sensible plates were installed in the air-handling units to recover heat between return and supply without mixing streams. The solid wall keeps the cooled supply air isolated from exhaust.
The result
Pre-cooling the supply air with recovered coolth reduced compressor and chiller load by about 35 percent during temperate months, with no added humidity risk and minimal maintenance thanks to the static core.