Case Study: Westin Copley Place Refurbishes Two Fresh Air AHUs

Westin Copley Place

Westin Hotels & Resorts is an American upscale hotel chain owned by Marriott International. The Westin Brand has 226 properties with 82,608 rooms in multiple countries in addition to 58 hotels with 15,741 rooms in the pipeline.

The Westin Copley Place is a AAA Four-Diamond hotel close to premium shopping and fine dining at Copley Place Mall. The hotel boasts family-friendly, pet-friendly accommodations, a 24-hour fitness studio, and over 57,000 square feet of modern event space.

The Problem:

A significant challenge was identified as the existing air handling units could not efficiently condition the air during periods of extreme temperature fluctuations. The system’s performance was hampered due to its reliance on make-up air sourced from the mechanical space, marking a suboptimal solution. This scenario created a need to elevate the fan performance, aligning with the increased demand, all while retaining the existing fan section size. The issue was made worse by space constraints in the mechanical room, which had become more congested. In certain spots, the clearances for component integration were measured to be less than 30″, presenting an obstacle in achieving the necessary enhancements.

Equipment Being Replaced:

Fans producing 24,000 CFM at 3” static pressure, coils, and controls.

The Solution:

Two Fresh Air AHUs were rebuilt and outfitted with new fans, coils, and controls to enhance the system’s efficiency in conditioning the airstream during peak cold and heat conditions. The previously encountered problem was rooted in inadequate fan performance, which necessitated an increase from 24,000 CFM at 3” static pressure to 30,000 CFM at 5” static pressure to comply with requirements, all while retaining the existing fan section size. Adding to the complexity was the historical nature of the building, where the mechanical room had become cluttered with equipment over the years, reducing clearances to under 30” in some areas and thus making component integration challenging.

The cornerstone of the solution was the deployment of Mainstream’s IntelliWall 5-fan array, powered by robust 7.5 HP PMEC motors. This state-of-the-art array was engineered for easy disassembly into single components, aiding in overcoming the spatial restrictions during the installation phase. A notable highlight of this upgrade was the retention of the existing 50 amp power feed despite the augmentation in airflow and static. This feature showcased a significant stride in optimizing energy consumption while achieving the desired performance metrics. Additionally, the design catered for flexibility in locating the control panel within the constrained mechanical room, further tailoring the solution to the unique challenges posed by the building’s layout.

The new system includes 7.5 HP PMEC motors, and 500mm impellers, embodied in the fan model UDP-500-7.5-460. The bulkhead array type is particularly chosen to ensure seamless integration and optimal performance. The system was designed with enough redundancy to achieve 95% of design airflow with one fan offline, showcasing the robustness of the solution.