Custom Temporary Pump Solutions for Major Airport Expansion

Challenge: Engineering a Multi-Phase Flush System During Active Airport Construction

A major international airport in the Southeast U.S. commissioned a new HVAC system as part of a large terminal expansion project. The installation of the new system in this active environment demanded an innovative approach to flushing — a critical cleaning process the pipes must undergo before the system can operate.

Mechanical pipe flushing is like power-washing the inside of pipes, but on an industrial scale. The process utilizes fluid velocity and chemical detergents through filtration to clean the pipe. Before installation, pipes are often exposed to the elements, causing oxidation and surface rust. During installation, pipes can accumulate debris from transport and metal deposits from welding. Without proper flushing, this debris could damage critical equipment, particularly the sensitive coils in the chiller system.

The project required a system that could handle four separate flushes — both hot water and chilled water systems — through 20-inch and 12-inch main lines with 3-inch laterals. Think of installing this new HVAC system like you were building a house's plumbing — except you're doing it in one of America's busiest airports where security and scheduling are paramount. Construction needed to proceed without disrupting daily airport operations, requiring careful coordination of all contractors and systems within high-security zones. Set-up and teardown were only allowed to be performed at night, and all equipment and personnel required security clearance and badging.

Set-Up: Designing a Flexible Dual-System Solution

Based on specifications provided by the airport’s lead contractor, our Sunbelt Rentals Pump Solutions team calculated that achieving 6 feet per second through the largest diameter pipe (24 inches) required a volume of 8,000 gallons per minute (GPM) at 81.4 total dynamic head (TDH). The first attempt at setup encountered complications: with multiple contractors working in the same area, the system wasn't fully ready for the flush. This required a complete teardown, resulting in a change order for a more flexible system design.

Due to carbon steel (CS) pipe size and flushing specifications, the system had to be split to accommodate different flow requirements:

• Large CS pipes (20–24 inches): Full system operation at 8,000 GPM
• Medium CS pipes (6–8 inches) Reduced flow at 2,000 GPM and 141.4 TDH
• Small CS pipes (3–4 inches): Precise control at 1,000 GPM and 239.5 TDH

The heart of the system consisted of two 12-inch by 12-inch by 17-inch Quiet Flow™ Diesel pumps, each housed in environmental containment skids designed to hold 120% of onboard fluids. These pumps featured indefinite run-dry capability, an environmentally safe priming system, and auto-start controls.

Our custom-engineered system utilized various HVAC and water management rental solutions, starting at the 24-inch Return Header. We used 12-inch Composite Hose to connect to a Steel Tee Manifold that divided the flow between two pumps. We installed isolation valves at each connection point, allowing us to service either pump without shutting down the entire system – critical for maintaining continuous operation.

Solution: Delivering Precise Flow Control Through Advanced Engineering

From the pumps, water flowed through independent 12-inch Composite Hose lines to another Steel Tee Manifold. We installed isolation valves throughout the system, allowing operators to control flow for system drainage and filling operations. The water then passed through dual Filtration Vessels before returning to the main Supply Header.

This flexible design proved crucial for handling different pipe sizes. For medium-sized pipes, we could run a single pump at 1,400 RPM to achieve the needed 2,000 GPM. Smaller pipes required special handling — we isolated them from the main system to prevent excess pressure and ran one pump at 1,750 RPM for precise 1,000 GPM flow control.

Our turnkey approach encompassed every aspect of the project. Beyond providing the engineered equipment setup, the team delivered comprehensive project management, including the initial engineered submittal, all equipment specifications, complete setup and teardown labor, mobilization planning, and ongoing system operation. This full-service approach was essential to working within the active airport environment.

The system's innovative design allowed for efficient adaptation to changing project needs. Operators could easily adjust pump speeds and flow rates when working with the smaller diameter pipes while maintaining optimal cleaning effectiveness. This flexibility, combined with the dual-pump redundancy and independent isolation capabilities, ensured continuous operation, even during maintenance or system adjustments.

From the initial equipment submittal to the final teardown, the Pump Solutions team's technical expertise in designing temporary pump systems ensured a smooth chiller installation process. By combining precise technical design with comprehensive project management, Sunbelt Rentals delivered a solution that met both the rigorous technical requirements of HVAC system commissioning and the practical demands of working in one of the nation's busiest airports. This full-service approach to critical infrastructure projects proves how the right combination of engineering expertise, equipment selection, and project execution can deliver superior results in even the most demanding environments.