Phoenix, Arizona




Comfort Systems


Jonathan Sihol

SmithGroup’s Office Remodel: Showcasing Innovative HVAC Solutions

SmithGroup, a renowned architecture and engineering firm, recently completed an office remodel project in their Downtown Phoenix location. This project demonstrates their expertise in delivering cutting-edge design and high-performance HVAC solutions.


The primary focus of the project was to showcase SmithGroup’s engineering expertise by implementing an efficient dehumidification system. They designed an innovative 100% outside air active chilled beams system with true humidity control. This resulted in optimized system efficiency, improved thermal comfort, and enhanced indoor air quality.

Design & Product Solutions

The project’s success can be attributed to the collaborative efforts of SmithGroup, Comfort Systems, and Varitec Solutions. Jonathan Sihol from SmithGroup served as the lead PE, overseeing both the architectural and engineering aspects of the project. Varitec Solutions introduced SmithGroup to Munters’ MEP concept, enhancing energy efficiency with chilled water systems operating at elevated temperatures.

The design incorporated a DX DOAS (Dedicated Outdoor Air System) unit with variable speed compressor technology. This system provides low dew point depression, allowing the chiller to serve the chilled beams independently and operate at an elevated 58°F chilled water temperature. This strategy has led to significant energy savings while maintaining optimal comfort levels in zones subject to large load swings, such as conference rooms and individual offices.

Key Products and Their Roles

Several carefully selected products were essential to achieving the desired performance and efficiency:

  • Dadanco’s Active Chilled Beams: Handle more primary air without increasing pressure drop and sound issues.
  • Motivair Air-Cooled Chiller: Provided necessary turn-down solution at low loads.
  • AnnexAir 100% Outside Air DX DOAS: Selected for its efficient thermal comfort, low dew point air conditioning capabilities, and state-of-the-art design.

Installation Challenges and Solutions

Despite challenges such as the small footprint of the DOAS unit and restricted roof space, the team successfully addressed these issues through careful product selection and configuration. The completed HVAC system has demonstrated excellent performance with no reported issues in humidity control.

Performance and Efficiency

Initial findings indicate that the chilled beam system, even without energy recovery on the DOAS, is operating 25% more efficiently than the evaluated water-cooled split heat pump design. This project showcases SmithGroup’s expertise in delivering innovative HVAC solutions and highlights the importance of collaboration and careful product selection in achieving superior energy efficiency and occupant comfort.