Century Plaza Towers
Century City , CA

In the heart of the Century City neighborhood of Los Angeles, California, the Century Plaza Towers stand as a remarkable landmark. As part of an effort to modernize the Towers, the management decided to replace 3 outdated Paterson-Kelley 12 Mill. Btu. hot water boilers with new, high-efficiency hot water heaters. The goal was to reduce energy consumption and CO2 emissions while ensuring the smooth operation of the buildings.

The Challenges

It was decided to replace the three old hot water boilers with 18 new RBI 2 Mill. Btu high efficiency condensing hot water heaters.

However, this ambitious project presented a number of challenges. One of the main challenges encountered during the design was the limited space available in the tight boiler room. Installing 18 new water heaters would have taken up a significant amount of space and running 18 steel chimneys to the outside was deemed impractical. Additionally, minimizing destruction and disruption to the existing infrastructure was a major concern.

ENERVEX Solution

The solution came from ENERVEX Southern California,

  • Design 3 banks each with 6 water heaters
  • Vent each bank with a common 18” Powerstack chimney system
  • Provide draft in each system was terminated with a twin RSV 400 mechanical draft system, providing redundancy.
  • Control the draft by EBC 31 Modulating Draft Controls to meet the varying demands of the water heaters.
  • Control the combustion air supply by retaining the orriginal fan
  • Integrate VFD and an EBC 31 controller to modulate the air supply as per the demands from the water heaters.

ENERVEX's expertise in designing complex exhaust systems played a crucial role in the successful outcome of the project. The entire project, from start to finish, took approximately five months, with ENERVEX handling the final commissioning.


By replacing the outdated boilers with high efficiency condensing hot water heaters and utilizing a unique chimney system design, the towers were able to reduce energy consumption and CO2 emissions. ENERVEX's expertise and efficient delivery played a crucial role in the project's success, ensuring the continued functionality and modernization of the Century Plaza Towers.





WM Group