HVAC Installation

A customer came to Barnhart with a challenge that involved installing multiple HVAC units through the side of a building at elevated heights in downtown Seattle. They needed a safe alternative to utilizing a material hoisting platform that would require employees to work at heights up to 100 feet. The HVAC units were to be installed on the 3rd, 5th, 7th, and 9th floors.

Barnhart proposed using its Mini Movable Counterweight Cantilever System (Mini MOCCS) with the site’s tower crane, an engineered rigging system that utilizes a counterweight package that moves via remote control along the beam to balance the load. Each HVAC unit was seven feet wide, seven to eight feet long and seven feet six inches tall and weighed approximately 2,000 pounds.

The floor to ceiling measurement of the opening was 12 feet. The team utilized an additional link on the Mini MOCCS to reduce overall height. This allowed use of the spreader bars at a lower rigging position. The overall height of the Mini MOCCS with an HVAC unit rigged and hanging was approximately 10 feet and six inches, leaving one foot and six inches of additional room.

The site was extremely congested due to neighboring job sites using the same loading and unloading area. Using a tower crane and the Mini MOCCS helped manage the congestion because it provided a faster, safer solution for the customer. The greatest benefit to utilizing the Mini MOCCS was not exposing employees to working at heights inside of a material hoisting platform or at the leading edge of the building.