ADC AD-115DR Installation Manual page 22

ALL ductwork should be smooth inside with no projections from sheet metal screws or other obstructions,
which will collect lint. When adding ducts, the ducts to be added should overlap the duct to which it is
connected. ALL ductwork joints must be taped to prevent moisture and lint from escaping into the building.
Additionally, inspection doors should be installed at strategic points in the exhaust ductwork for periodic
inspection and cleaning of lint from the ductwork.
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 (i.e., roof
or ground level).
IMPORTANT: Exhaust back pressure measured by a manometer/magnehelic in the exhaust duct
must be no less than 0 and must not exceed 0.3 in WC (0.74 mb) for AD-115ES
and 0.6 in WC (1.48 mb) for AD-115DR.
NOTE: It is recommended that exhaust or booster fans not be used in the exhaust ductwork system
except where necessary to maintain exhaust back pressure (in the exhaust duct) between zero
and 0.3 inch water column for AD-115ES and 0.6 inch water column for AD-115DR. Where
employed, booster fans must not activate the dryer airflow proving switch (sail switch) when
the dryer is not in operation.
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.
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 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 the nearest obstruction.
IMPORTANT: DO NOT use screens, louvers, or caps on the outside opening of the exhaust
ductwork.
2. AD-115ES Single Dryer Venting
When possible, it is suggested to provide a separate exhaust duct for each dryer. The exhaust duct should
be laid out in such a way that the ductwork travels as directly as possible to the outdoors with as few turns
as possible. It is suggested that the use of 90° turns in ducting be avoided; use 30° and/or 45° angles instead.
The shape of the exhaust ductwork is not critical as long as the minimum cross section area is provided.
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