The York FlexSys underfloor air distribution lab includes a simulated office setting.
YORK, Pa. — York International Corporation has opened what it says is a unique underfloor air distribution laboratory here at its world headquarters. The company intends to use the lab for research, training, and demonstrations of its FlexSys variable air volume (VAV), underfloor air system.

The lab includes an environmental chamber to simulate both cooling and heating conditions in a commercial office setting, comprised of a 700-square-foot room with three interior walls, one exterior glass window-wall, a 10-foot ceiling, and common office equipment. The demonstration office is built on a Tate raised-access floor, which incorporates underfloor air delivery as well as power, voice, and data cabling.

It also contains a conventional overhead VAV air system for comparison purposes.

Joseph Halza, York’s FlexSys product manager, said that it is the capability to test system performance under a full range of simulated building loads that makes the laboratory unique. A 14-ton, air-cooled chiller and 3,000-cfm air-handling unit with variable-speed drive supply conditioned air. The environmental chamber, located on the “outside” of the glass window-wall, enables load simulations and is controlled with a 2-ton refrigeration system and a 37.5-kW infrared heating system. Window-wall temperatures can be created and controlled from -10 degrees F to 120 degrees F, so both heating- and cooling-mode analyses can be conducted.

A temperature sensor tree inside the demonstration office records temperatures from floor to ceiling. Smoke is induced to visually monitor airflow patterns.

“Many aspects of system performance can be demonstrated — energy consumption, air quality, and flexibility of the system to address building churn, among others. Now, we can demonstrate unequivocally the benefits of our variable air volume, underfloor air system, and use the lab for ongoing research and development of new technology.”

Compared to a conventional overhead system, Halza said the FlexSys underfloor air system saves energy via a lower fan static pressure, a higher supply-air temperature (creating more opportunity for economizer cycle), and because cooling is directed to the “occupied zone,” not the entire height of the room. Room IAQ is improved with the upward flow of air, with particulates congregating toward the ceiling, above the breathing space, he said. Rearranging office space is simplified, since a FlexSys floor panel can be moved easily and quickly — in under four minutes in most cases, he stated.

Halza noted the laboratory opened with initial demonstrations for building owners, architects, and engineers. A contractor training program is available. Prospective customers may arrange a visit and demonstration program (requiring 6-8 hours) by contacting their nearest York office. A list of offices and phone numbers is available on the company’s Web site at

Publication date: 03/17/2003