American Dryer Corp. T20 User Manual

Page 12

JLA Limited

113428-9

Outside Ductwork Protection

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 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 (refer to the diagram).

Important

Do not use screens, louvers, or caps on the outside
opening of the exhaust ductwork.

Single Dryer Venting

Important

For extended ductwork runs, the cross-sectional
area of the ductwork can only be increased to an

extent. When the ductwork approaches the maximum limits
as noted in this manual, a professional HVAC firm should be
consulted for proper venting information.

NOTE 1 Opening from combustible materials must be 2-inches (5.08 cm) larger

than the duct (all the way around). The duct must be centered within
this opening.

NOTE 2 Distance should be 2 times the diameter of the duct to the nearest

obstruction.

A = T20 Stack - 20 feet (6.10 meters)

T30 Stack - 12 feet (3.66 meters)

B = 8-inches (20.32 cm)

The length of the ductwork from the dryer to the outside exhaust
outlet, must not exceed 12 feet (3.66 meters) for the T30 stack
and 20 feet (6.10 meters) for the T20 stack. The minimum
diameter of this ductwork must be at least 8-inches (20.32
cm) even though the dryer exhaust duct connection is
smaller. Including tumbler/dryer elbow connections or elbows
used for outside protection from the weather, no more than 4
90° elbows should be used in the exhaust duct run. If more
than the equivalent of 4 90° elbows are used, the cross-
sectional area of the ductwork must be increased.

Multiple Dryer (Common) Venting

Important

For extended ductwork runs, the cross-sectional
area of the ductwork can only be increased to an

extent. When the ductwork approaches the maximum limits
as noted in this manual, a professional HVAC firm should be
consulted for proper venting information.

If it is not feasible to provide separate exhaust ducts for each
dryer, ducts from individual dryers may be channeled into a
“common main duct.” The individual ducts should enter the
bottom or side of the main duct at an angle not more than 45º
in the direction of airflow. The main duct should be tapered,
with the diameter increasing before each individual duct is
added. The minimum diameter of the individual ductwork must
be at least 8-inches (20.32 cm).

Important

No more than 4 dryers should be connected to 1
main common duct.

NOTES ____________________________________

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