VERTICAL VENTING
When vertical single venting is used minimum duct size is 12 inches (refer to Illus. B below), the duct work from the dryer to the outside outlet cannot exceed 60 feet (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.
Illus. B
If the length of the duct run or quantity of elbows used exceeds the above noted specifications, the cross section area of the duct work must be increased in proportion to the number of elbows or duct run added.
IMPORTANT: For extended duct work runs, the cross section area of the duct can only be increased to an extent. For extended duct work runs, a professional HVAC firm should be consulted for proper venting information.
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