ADC ML-25V Installation Manual page 16

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 so long as the minimum cross-sectional area is provided. 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 for Horizontal Venting and Illus. D for Vertical Venting).
IMPORTANT: No more than four (4) dryers maximum should be connected to one (1) main
common duct with a vertical run.
NOTE: Distance between dryer single ducts being connected to the main common duct must be a
minimum of 34-1/4" (87 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.
The illustrations on page 17 show the minimum cross section area for multiple dryer venting. These figures must
be increased in proportion if the main duct run from the last dryer to where it exhausts has numerous elbows or is
unusually long.
IMPORTANT: For extended ductwork runs, the cross section area of the duct can only be increased
to an extent. For extended ductwork runs, a professional HVAC firm must be
consulted for proper venting information.
Refer to page 17 for Multiple Dryer Horizontal Venting and Vertical Venting examples/illustrations.
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