American Dryer Corp. MDG-120PVV - Manual (Page 18)

16 Maytag Co. 113395 - 6
E. EXHAUST REQUIREMENTS
Exhaust ductwork should be designed and installed by a qualified professional. Improperly sized ductwork will
create excessive back pressure, which results in slow drying, increased use of energy, and shutdown of the
burner by the airflow (sail) switch, burner hi-limits, or lint chamber hi-limit protector thermostat. The dryer must
be installed with a proper exhaust duct connection to the outside.
The dryer shall not be exhausted into any gas vent, chimney, wall, ceiling or concealed space of a building.
CAUTION: This dryer produces combustible lint and must be exhausted to the outdoors. Improperly
sized or installed exhaust ductwork can create a potential fire hazard.
The ductwork 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. There should be a minimum 6-inch (15.24 cm) clearance between the back
guard and the first bend in the ductwork for ease of servicing. Single or independent dryer venting is recommended.
It is suggested that the use of 90° turns be avoided; use 30° and/or 45° bends instead. The radius of the elbows
should preferably be 1-1/2 times the diameter of the duct. ALL ductwork should be smooth inside with no
projections from sheet metal screws or other obstructions, which will collect lint. When adding ducts, overlap
the duct being connected. ALL ductwork joints must be taped to prevent moisture and lint from escaping into
the building. Back draft dampers must be installed in ALL commonly ducted systems. Inspection doors
should be installed at strategic points in the exhaust ductwork for periodic inspection and cleaning of lint from
the ductwork.
IMPORTANT: It is recommended that exhaust or booster fans not be used in the exhaust ductwork
system.
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).
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.
NOTE: As per the National Fuel Gas Code, “Exhaust ducts for type 2 clothes dryers shall be
constructed of sheet metal or other noncombustible material. Such ducts shall be equivalent in
strength and corrosion resistance to ducts made of galvanized sheet steel not less than 26
gauge (0.0195-inches [0.50 mm]) thick.”
The ductwork for this appliance must be suitable for the appliance category in accordance with national installation
regulations of the country of destination.
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.