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NOTE:
When the exhaust ductwork passes through a wall, ceiling, or roof made of combustible
materials, the opening
must be
2-inches (5.08 cm) larger than the duct (all the way around).
The duct
must be
centered within this opening.
d. Outside Ductwork Protection
1) To protect the outside end of the horizontal ductwork from the weather, a 90° elbow bent downward
should be
installed where the exhaust exits the building. If the exhaust ductwork travels vertically
up through the roof, it
should be
protected from the weather by using a 180° turn to point the
opening downward. In either case, allow at least twice the diameter of the duct between the duct
opening and nearest obstruction.
IMPORTANT: DO NOT
use screens, louvers, or caps on the outside opening of the exhaust
ductwork.
Содержание AD-115ES II
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