Commercial HVAC Replacement Without Disruption

How the 64-story U.S. Steel Tower Replaced a Critical Fan Without Shutting Down

Commercial Real Estate

Overview

The U.S. Steel Tower in Pittsburgh, PA, is a 64-story skyscraper and the tallest building in the city. With 2.3 million square feet of leasable space and 8,000–10,000 occupants daily, uninterrupted operations are critical.

When one of the building’s original 1967 centrifugal fans—serving 14 floors—failed, the repair posed significant risks: two weeks of downtime, cutting an access hole in the building’s exterior, and crane operations in the middle of the city.

Havtech, working with manufacturer Q-PAC and contractor K&I Sheet Metal, delivered a pre-engineered fan system that was installed in less than 48 hours, avoiding major disruption and ensuring compliance with the building’s LEED certification requirement.

Challenge

Keeping the nation’s 16th largest building fully operational is no small task. When a massive 6,000-lb. centrifugal fan serving 14 floors failed, the facility team faced a tough choice: attempt a disruptive two-week repair that required cutting into the building’s exterior, or find a smarter, faster alternative.

Aging Equipment: Original 6,000 lb. centrifugal fan from 1967 required major repair.
Structural Constraints: Access limited to a 30-inch door; repair would have required cutting into the building exterior.
Operational Risk: Estimated two-week downtime would disrupt daily operations for up to 10,000 occupants.
Sustainability Goals: As one of the largest LEED-certified buildings in the world, the solution needed to maintain high filtration and fresh air exchange standards.

Solution

Havtech recommended and supplied a Q-PAC modular fan system, which was designed to:

Match the exact airflow (CFM) capacity of the original unit.
Fit through the narrow 30-inch access door for simple delivery.
Arrive pre-engineered with power and control wiring for rapid installation.
Provide additional static pressure to meet LEED building requirements.

Installation began on Friday evening and was completed by Sunday morning, ensuring the tower was fully operational before Monday’s workday

Conclusion

Havtech’s collaboration with Q-PAC transformed a critical equipment failure into an opportunity to modernize the building’s systems without disruption. The U.S. Steel Tower now benefits from a reliable, efficient fan system that supports LEED certification and reduces long-term costs — all installed over a single weekend.

Details:

Mechanical Contractor:
K&I Sheet Metal

Building Type:
Commercial Building

Square Footage:
450,000 sq. ft.

System Installed:
Q-PAC modular fan system replacing legacy centrifugal fan

Results

Space Optimization

Smaller footprint than original fan system.
Fit through existing access without structural modifications.

Minimal Downtime

Installed over a single weekend.
The tower remained fully operational for Monday’s return-to-work.

Reduced Maintenance Costs

A modular system with fewer parts means fewer failure points.
Reduced labor hours and long-term service costs.

Energy Efficiency

The system reduces energy use by two-thirds compared to the original fan.

“The Q-PAC system brought our AHU up to date with state-of-the-art, cutting-edge technology. The speed of installation and disruption-free process was impressive, and the maintenance-free design is a major long-term benefit.”