American Dryer Corp. ML-96HS User Manual
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IMPORTANT: For extended duct work runs, the cross section area of the duct work can only be
increased to an extent. Maximum proportional duct work runs cannot exceed fifteen
(15) feet with two (2) elbows. When the duct work approaches the maximum limits
as noted in this manual, a professional HVAC firm should be consulted for proper
venting. HVAC should be consulted for proper venting information.
IMPORTANT:
Exhaust back pressure measured by a manometer at each dryer exhaust duct area should
not exceed .3 inches of water column (W.C.).
The duct work should be smooth inside with no projections from sheet metal screws or other obstructions
which will collect lint. When adding ducts, the duct to be added should overlap the duct to which it is to be
connected. ALL duct work joints must be taped to prevent moisture and lint from escaping into the
building. Inspection doors should be installed at strategic points in the exhaust duct work for periodic
inspection and clean-out of lint from the duct work.
NOTE: Where the exhaust passes through a wall, ceiling, or roof made of combustible materials, the
opening must be 2-inches larger (all the way around) than the duct. The duct must be
centered within this opening.
a. Outside Duct Work Protection
1) To protect the outside end of horizontal duct work from whether, a 90º elbow bent downward should be
installed where the exhaust exits the building. If the duct work travels vertically up through the roof, it
should be protected from the whether by using a 180º 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 or caps on the outside of opening of exhaust duct work.