Copyright Goodheart-Willcox Co., Inc. 112
Summar y
■ Ducts are round or rectangular pipes used to carry conditioned
air. Duct systems should be designed, fabricated, and installed in
compliance with industry-accepted guidelines and standards.
■ A system’s ductwork consists of return air and supply air sections.
Supply and return plenums are connected directly to the air handler.
■ Primary supply trunks supply air to branch runouts or secondary
supply trunks. Secondary supply trunks supply air to branch
runouts or other secondary supply trunks.
■ Branch runouts connect the primary or secondary supply trunks to
supply registers.
■ Plan views and elevation views for ductwork provide different
information. The measurement provided fi rst in a dimension
repesents the side of duct viewed in the drawing.
■ Notes and symbols on duct drawings must be read carefully to
avoid missing potentially important information.
■ Duct fi ttings are sections of ductwork that change the direction
or size of a duct run. They have construction numbers assigned to
them.
■ Two common supply air fi ttings are the bullhead and tapered head.
■ Common duct fi ttings include takeoff, transition, offset, and elbow
fi ttings.
■ Transition fi ttings change the cross-sectional measurements of a
duct, while offset fi ttings route ductwork runs around vertical or
horizontal obstructions.
■ Takeoff fi ttings connect the branch runout to the main supply duct.
■ Boot fi ttings connect the branch runout to the register or grille.
■ Registers, grilles, louvers, and diffusers are duct system accessories
that help a duct system function effectively and effi ciently. Louvers
have fi xed vanes, whereas grilles can have adjustable vanes.
■ Registers are grilles that have dampers to adjust the direction and
volume of air passing through them. Transfer grilles allow air to
fl ow freely between two adjacent conditioned spaces in the same
zone.
■ Dampers are used to increase or decrease airfl ow to a particular
area or zone. They can be manually or automatically controlled.
■ Smoke and fi re dampers are used to close off sections of duct in the
event of a fi re.
Summar y
■ Ducts are round or rectangular pipes used to carry conditioned
air. Duct systems should be designed, fabricated, and installed in
compliance with industry-accepted guidelines and standards.
■ A system’s ductwork consists of return air and supply air sections.
Supply and return plenums are connected directly to the air handler.
■ Primary supply trunks supply air to branch runouts or secondary
supply trunks. Secondary supply trunks supply air to branch
runouts or other secondary supply trunks.
■ Branch runouts connect the primary or secondary supply trunks to
supply registers.
■ Plan views and elevation views for ductwork provide different
information. The measurement provided fi rst in a dimension
repesents the side of duct viewed in the drawing.
■ Notes and symbols on duct drawings must be read carefully to
avoid missing potentially important information.
■ Duct fi ttings are sections of ductwork that change the direction
or size of a duct run. They have construction numbers assigned to
them.
■ Two common supply air fi ttings are the bullhead and tapered head.
■ Common duct fi ttings include takeoff, transition, offset, and elbow
fi ttings.
■ Transition fi ttings change the cross-sectional measurements of a
duct, while offset fi ttings route ductwork runs around vertical or
horizontal obstructions.
■ Takeoff fi ttings connect the branch runout to the main supply duct.
■ Boot fi ttings connect the branch runout to the register or grille.
■ Registers, grilles, louvers, and diffusers are duct system accessories
that help a duct system function effectively and effi ciently. Louvers
have fi xed vanes, whereas grilles can have adjustable vanes.
■ Registers are grilles that have dampers to adjust the direction and
volume of air passing through them. Transfer grilles allow air to
fl ow freely between two adjacent conditioned spaces in the same
zone.
■ Dampers are used to increase or decrease airfl ow to a particular
area or zone. They can be manually or automatically controlled.
■ Smoke and fi re dampers are used to close off sections of duct in the
event of a fi re.