In 2017, we were contracted alongside ARCO and GMA to build an expansion for a client in Rice, Minnesota.
The expansion added a new freezer, a new 28 ℉ room, a new 34 ℉ room, and a dock. The customer was also looking for a low-charge, energy-efficient, rooftop unit–a perfect fit for our then-new Master Series unit. The client elected to run the unit on R507.
The low-charge Master Series unit that we built was a compact 11.5 ft wide and 38 ft long, and fit perfectly in the limited rooftop space. We modeled the unit ahead of time in 3D to ensure that it would fit within the highly specific needs of this project, while still being easily serviceable.
Once completed, the 65,000 lb Master Series unit was lifted by crane onto the roof of the facility, and joined 2 condensers, 3 Bitzer screw compressors, and 11 direct expansion evaporators. We also installed our PLC system, and a motor control center with a state-of-the-art human-machine interface.
The system was designed with two suction groups: a medium-temperature suction group (for rooms 20 ℉ and warmer) and a low-temperature group (for rooms at -20 ℉). It relies completely on air-cooled condensers and adiabatic cooling, which has greatly reduced the facility’s water cost. And best of all: the project was completed ahead of schedule.