Installation manual
16
a. Outside Ductwork Protection
1) To protect the outside end of horizontal ductwork from the weather, a 90° elbow bent downward
should be installed where the exhaust exits the building. If the 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 the nearest obstruction.
IMPORTANT: DO NOT use screens, louvers, or caps on the outside opening of the exhaust
ductwork.
2. Single Dryer Venting
IMPORTANT: For vertical venting the minimum duct size is 20-inches (50.8 cm) for a round duct and
24-inches (60.96 cm) for round horizontal venting. THE DUCT SIZE MUST NOT
BE REDUCED ANYWHERE DOWNSTREAM OF THE DRYER.
IMPORTANT: Exhaust back pressure measured by a manometer at each basket (tumbler) exhaust
duct area must be no less than 0 and must not exceed 0.3 inches (0.74 mb) of water
column (W.C.).










