What is in this article?:
- Variable-Refrigerant-Flow Zoning Remedy for Long-Dormant Sick Building
- VRF Zoning Flexibility Paramount
- Earning LEED Silver Certification and a Six-Figure Utility Rebate
The design team selected a variable-refrigerant-flow (VRF) zoning system from Mitsubishi Electric Cooling & Heating.
“For over a decade, Towson had to endure the presence of this 15-story ‘sick building’ in the heart of its commercial district,” Arsh S. Mirmiran of Caves Valley Partners said of Towson City Center. Today, the office tower is “a showcase for sustainability and modernization.”
VRF Zoning Flexibility Paramount
“Because Mitsubishi’s multiport controller makes the system so flexible, we were able to easily orchestrate the piping and wiring for each floor,” Wagner said. “It is so much easier and less costly to install that individual zoning becomes immediately available. When a building is not yet leased and there is no interior tenant-improvement plan, this system allows you to install indoor fan coils when space becomes rented and rooms identified.”
Mitsubishi Electric’s low-profile (9-7/8 in.) indoor fan coils helped the design team overcome the limitations posed by the low decks. (Traditional fan coils can be as much as 18 in. deep by 14 in. wide.) Twenty-seven Mitsubishi Electric outdoor units, meanwhile, fit neatly on the roof, freeing up the entire 12,000-sq-ft 13th floor, which had been the mechanical room. With the removal of the original boilers and chilling tower, the former mechanical room became usable storage space.
“With the complete penthouse now available, we added a water-cooled glycol loop to the 13th floor in case a tenant wanted to add a data center,” Wagner said. “We also put a dedicated outdoor-air system utilizing total energy and desiccant wheels on the removed cooling-tower steel grillage so that dehumidified, conditioned ventilation air was made available for distribution to downstream fan-coil units, greatly reducing the energy demanded by each fan coil. We also added Mitsubishi Electric VRF zoning fan coils in the garage and elevator lobbies.”
Seventy percent of the shaft space needed by the outdated system was filled in, significantly increasing the leasable space on each floor.