Close-coupled, chilled water cooling is designed for medium to large data centers. Placing the unit in the row of racks moves the source of cooling closer to the heat load. This eliminates air mixing and provides a predictable cooling architecture. It allows chilled water to be connected from the top, if routing from overhead, or bottom, if on a raised floor. Monitors and actively adjusts cooling capacity to ensure proper server inlet temperatures. Through the microprocessor controller, visibility into the operation and health of the unit is provided.