AARP Main Plant Modernization

General Contractor:  Shapiro & Duncan
Architect:  N/A
Engineer:  Global Engineering Solutions
Final Contract Amount:  $5,274,614
Start Date:  10/14/2015
Completion Date:  3/22/2016

Challenges

The scope of the AARP Main Plant Modernization project involved renovation of an outdated HVAC central plant to an energy efficient modern system. The plant supplies chilled and hot water to the clients occupied headquarter office building, which includes a working video/sound recording studio, data center and employee cafeteria. 

Our biggest challenge was keeping the mechanical system online continuously during the project. Climate control had to be maintained throughout the building and the facility could never go without chilled water.

For this reason, the project was executed in four phases, the first three of which required replacement of one or more cooling towers and associated chillers and pumps. In the fourth phase, a 600-watt Cummins generator was replaced. Each stage had to be completed and commissioned before going on to the next one.

Another one of our top-level challenges, literally and figuratively, was the fact that almost all of the work took place on the rooftop of a fully occupied office building in the heart of downtown Washington, D.C. – in the middle of winter (additional mechanical work included the replacement of the ventilation system in the underground parking garage). Needless to say, this created a difficult set of jobsite staging issues.

Solution

As with every Shapiro & Duncan project, our solution began with a careful coordination process spearheaded by our Virtual Design Coordination (VDC) team. They relied on data captured by digital scanning tools used by our field people to virtually “map” each mechanical space in the building. Next, models were designed for all of the piping and connections for the pumps, chillers and cooling towers. Then, these models were shared with our field teams to get their input on how to segment the piping models into spools for prefabbing at our 51,000 square foot fabrication shop in Landover, Maryland.  Creation of these piping spools also made for smooth transport by truck to the jobsite as well as trouble-free installation once on site.

Up on the roof, work had to be done on Saturdays. To make sure everything was properly positioned or in motion when the crane arrived on the scene, our project management team made effective use of pull planning to schedule equipment deliveries by working back from the completion date of each phase. In addition, even though wind and weather forced four cancellations of crane service, our field teams were able to keep the job on track by using the elevator to bring up smaller spools of piping to keep the project advancing.

Here is the complete rundown of the mechanical and plumbing equipment and system components used in our AARP solution:

• Penthouse Equipment
  • Two Trane 530-ton variable speed screw chillers with unit mounted variable frequency drives (VFDs) and control panels
  • One Trane 420-ton pony variable speed screw chiller with unit mounted VFD and control panel
  • Two BAC 975 gallons-per-minute (GPM) induced draft crossflow cooling towers with two 20 horsepower (HP) remote mounted VFD control panels
  • Six B&G vertical double suction split case pumps
  • Six ABB Pump VFD’s (two 60 HP, three 50 HP and one 25 HP)
  • One B&G 132-gallon expansion tank
  • One B&G 45 GPM air separator
  • Field-welded cooling tower structural steel support vibration isolation frame
  • Cat walk platform, stairs and railing system around cooling towers
  • One i-Vu remote touch screen chiller interface panel
  • Refrigeration monitoring systems
  • Refrigeration exhaust fan system and fan VFD
  • Siemens Control system optimization program
  • Remote usage dashboard
  • Curtic Engine 800 kilowatt (kW) diesel genset with built-in day tank
  • Exterior precast louvers
  • Siemens direct digital building automation control system
  • ARC hydronic water treatment system
  • Specified Electrical system
  • ADJ air distribution sheet metal
  • GOEL thermal insulation
  • Chiller and condenser water piping systems

• Parking Garage Equipment
  • Seventeen Greenheck sidewall mounted supply and exhaust fans with wall housings
  • Ten 5 HP fan VFD’s
  • CO2 monitoring system.
  • Electrical wiring
  • Air distribution sheet metal
  • Thermal insulation
  • Diesel genset fuel oil pump set
  • Piping heat trace system

Result

Our team met all of the challenges head on and completed the project on time and on budget. Climate control and chilled water service were maintained continuously, as required by the owner. In fact, most of the building occupants didn’t even know the work was being done. Keeping everything in motion, without becoming a distraction to the occupants, took extremely close communication on the job from start to finish.

Douglas Byrnes of Jones Lang LaSalle, the senior chief engineer in charge of the building, could not have been more complimentary. In an August 31, 2016 letter to Shapiro & Duncan’s president Jerry Shapiro, he wrote:

“I wanted to express my gratitude and appreciation for the professionalism, project management and workmanship that was exhibited by the management team and all the skilled tradesmen that were involved in the chiller plant modernization. I was very impressed with the craftsmanship exhibited. . .and the pride taken in the work, in doing the job right. . .The Shapiro & Duncan computer software technology and advanced fabrication equipment allowed the chillers, piping and cooling towers to be replaced during the winter months, with the building ready for full cooling for the summer of 2016. Our client now has a fully modernized, computer operated, energy efficient chiller plant that will serve the building for 30 years.”

The AARP project demonstrates, once again, that the Shapiro & Duncan team will do whatever it takes to complete a project to the customer’s total satisfaction.