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113243-1 www.amdry.com 7
No more than eight (8) dryers maximum should
be connected to one (1) main common duct
with a vertical run.
When vertical single 10-inch (25.4 cm) venting is used (refer
to Illus. B below), the ductwork from the dryer to the outside
outlet cannot exceed 60 feet (18.28 meters), refer to Illus. B
below. This calculation compensates for the use of a
maximum of three (3) elbows including the two (2) elbows
creating the 180° (turned downward) outside outlet.
If the length of the duct run or quantity of elbows used exceeds
the above noted specifications, the cross section area of the
ductwork must be increased in proportion to the number of
elbows or duct run added.
For extended ductwork runs, the cross section
area of the duct can only be increased to an
extent. For extended ductwork runs, a
professional heating, ventilating, and
air-conditioning (HVAC) firm should be
consulted for proper venting information.
MULTIPLE DRYER (COMMON) VENTING
If it is not feasible to provide separate exhaust ducts for each
dryer, ducts for individual dryers may be channeled into a
common main duct. Each dryer is provided with a back draft
damper. The individual ducts should enter the bottom or
side of the main duct at an angle not more than 45° in the
direction of the airflow.
The main common duct may be any shape provided that the
minimum cross-sectional area is maintained. The main duct
should be tapered with the diameter increasing before each
individual 8-inch (20.32 cm) duct is added (refer to Illus. C
Distance between dryer single ducts being
connected to the main common duct must be
a minimum of 31-3/8 (79.69 cm) dryer width.
Ductwork should be laid out in such a manner
where allowances are made at rear area of the
dryer for removal of rear service panels or guards.