PROJECT DESCRIPTION
McMurry Medical office building is a 3-story building with multiple different tenants. Tenants include and not limited to plastic surgery office, physical therapy, optometrist clinic, pharmacy, outpatient clinic, lab, and offices. Building is served by a medium pressure system that includes a main air conditioning unit on the roof, which works in conjunction with a fan powered units sub-system. Also, general exhaust system is designed for this building to accommodate toilets rooms. Below is a detailed description of the building HVAC system.
Air Conditioning for this building is provided by one Variable Air Volume Rooftop unit. AC units are serving separate tenant spaces. In conjunction with the large AC unit, Fan Terminal Units (FTU) serves the perimeter areas for freeze protection and the First Floor Main Lobby area.
In addition to the large VAV unit, there are two Carrier Split System Air Conditioning units to serve specialty areas in the building. Indoor Fan Coil Unit FCU-1 and outdoor condenser unit CU-1 serve the First Floor Data Room. Indoor Fan Coil Unit FCU-2 and outdoor condenser unit CU-2 serve the first floor Elevator Machine Room.
The large VAV Packaged Rooftop unit supply conditioned air to the FTU units. The FTU units respond to a space or zone temperature sensor and vary the amount of supply air being delivered to the space to maintain space comfort.
In operation, the Carrier Split System Air Conditioning units respond directly to a space temperature sensor, and modulate the supply air temperature as needed to maintain space comfort.
Ductwork runs location and sizes were coordinated with all trades for clearance requirements in the building. Also, all design for this project complied with the 2003 Washington State Building/Mechanical Code with Seattle amendments, the 2003 WA State Energy Code with Seattle amendments, and the Washington Administrative Code (WAC). Fire/Smoke dampers and Fire Dampers were provided at all areas where ducts and transfer openings penetrated though rated assemblies/exit enclosures, per building code.
In addition to the Packaged Rooftop Air Conditioning units, the HVAC system has other components necessary for the operation of the system:
(1) Exhaust Fan EF-1 for general exhaust.
(1) Ceiling Exhaust Fan EF-2 for Janitor Closet.
BUILDING MANAGEMENT CONTROL SYSTEM
PACKAGED AIR CONDITIONING UNITS
The Packaged Rooftop Air Conditioning units are controlled by a individual programmable thermostats. Each unit responds to its space thermostat by staging compressor(s) and or heaters to vary the supply air temperature in response to space comfort needs.
EXHAUST FANS
EF-1 and EF-2 are controlled by controlled by the EMCS.
BASIS OF DESIGN CRITERIA
- Summer Indoor = 74°F
- Winter Indoor = 70°F
- Summer Outdoor = 83°F DB/67° WB
- Winter Outdoor =17°F D
- Lights = 1.2 watts/sq. ft.
- Misc. load allowance = 2.5 watts/sq. ft.
- Ventilation = 20 CFM/person
- Occupancy = 1 person per 143 square feet