Digi-Key Electronics’ multi-level facility interior.
Booming e-commerce at Digi-Key Electronics made it necessary to embark on a 2.2 million square-foot expansion to their headquarters in Thief River Falls, Minnesota. The addition would yield a 3 million-square-foot multi-level manufacturing facility that would be the workplace for 3,400 employees and serve as a new distribution hub.
With ceilings from 18’ to 74’, the expansive factory had an evolving floor-to-ceiling layout and an extensive conveyor storage system. The challenge for engineers, especially within the conveyor storage area, was to keep temperatures and humidity within a specific range from floor to ceiling with low air velocity. Strategic piping and placement of highly efficient air rotation systems would be necessary, as would staying within budget and ease of long-term maintenance.
SVL worked with engineer Widseth Smith Nolting and manufacturer Johnson Air-Rotation HVAC Systems to identify the best configuration for optimal efficiency. The factory’s varying ceiling heights were no problem for 26 Johnson Air-Rotation units (16 for heating and cooling and ten more just for airflow.) In addition, the design incorporated steam generators, DX cooling, and gas heat to reduce static electricity during Minnesota’s frigid winter months. The conveyor storage system area received three large air rotation units that keep humidity constant and temperatures (floor to ceiling) within 8°F.
“Ductwork could not be run in a traditional fashion in most areas,” explains Widseth engineer Adam Siemers. “We were looking for low-footprint solutions to condition the space without extreme amounts of ductwork. Although some areas used rooftop units and traditional ductwork, the Johnson Air-Rotation Units were used to condition the majority of the building with high-volume, low-speed air. Units with heating and cooling were stationed around the perimeter, while the inner portions of the building used fan-only units to further homogenize and destratify the temperature and humidity conditions.”
Despite the factory’s high ceilings, Johnson Air-Rotations’ systems now maintain comfortable air throughout the facility. They also accommodate humidification dispersion grids created by other manufacturers, making it a great budget-friendly choice.
One of Digi-Key’s 26 air rotation units.
The heating and cooling air-rotation systems and air-only stratification systems provide a total output of 1.235 million CFM. Special thanks go to Johnson Air-Rotation HVAC Systems for providing engineering and design assistance to SVL and Widseth Smith Nolting to achieve optimal product performance and ease of maintenance.
Robert Gibb and Sons, Inc. completed the installation and commissioning on schedule and budget. Digi-Key Electronics now has an efficient air system to provide consistent temperature and humidity control of its entire factory.
“With a project of this immense scope, there are myriad coordination requirements,” says SVL sales engineer Kevin Herrema. “The project team all worked well together for a successful completion.”
To learn more about Johnson Air-Rotation HVAC Systems, contact your SVL Sales Representative.