06-06
7.5 DUCTWORK DRAWINGS
A. The minimum duct size shall be 8" x 6".
B. Complete flow diagrams of the supply air, return air and exhaust air
systems shall be shown on the drawings. Flow diagrams shall show the
CFM required in all mains and major branches (such as zone/floor) and
the size of each main and major branch. Flow diagrams shall show and
identify all air handling units, fans, and other major components in
the air system. These diagrams are to facilitate checking and air
balancing.
C. Manual air volume balancing devices shall be provided in applicable
supply, return and exhaust mains, branch mains and terminal branches.
Ceiling access panels are to be installed, where required, for access
to balancing devices. Location of balancing devices shall be shown on
the contract drawings.
D. Dampers in room diffusers and registers shall be used only for minor
balancing requiring a maximum pressure drop of approximately 0.10
inch of water gage. Registers and/or diffusers shall not be located
on main ducts or main branches, but on individual branch ducts with
opposed blade balancing dampers in the branch to reduce room noise
transmission.
E. Air quantities on plans shall be "rounded off" to the nearest
increment of 10 cfm.
F. Smoke detectors for air conditioning systems are specified in the
Electrical Specifications, but the locations at air handling units
shall be shown on the "H" drawing control diagrams and floor plans.
Coordinate diffuser location and blow direction with space detector
locations shown on the Electrical Drawings to avoid false smoke
alarms caused by air discharge.
G. Provide fire dampers and smoke dampers in accordance with Article 3,
HVAC SYSTEMS. Provide a schedule for smoke dampers showing sizes,
pressure drops, and compliance with the maximum velocity limit. Show
duct transitions on drawings.
7.6 CALCULATIONS
A. Calculations shall include room by room heat gain and loss; room by
room air balance showing supply, return, exhaust, transfer, and
make-up air quantities; equipment capacities; economic analysis; and
sound and vibration analysis.
Calculations and analysis should be
identified, arranged and summarized in proper format.
They shall be
indexed in a bound folder with each air handling unit as a zone and
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