2.Single Dryer Venting
Where possible, it is suggested to provide a separate exhaust duct for each dryer. The exhaust duct 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. It is suggested that the use of 90° turns in ducting be avoided; use 30° and/or 45° angles instead. The shape of the exhaust ductwork is not critical so long as the minimum cross section area is provided.
IMPORTANT: Minimum duct size for a gas, electric, or steam dryer with a vertical run and not more than three (3) elbows (including dryer connection and outside outlets) is
DOWNSTREAM OF DRYER.
IMPORTANT: Exhaust back pressure measured by a manometer at each basket (tumbler) exhaust duct area must not exceed 0.3 inches (0.74 mb) of water column (W.C.).
It is suggested that the ductwork from each dryer (minimum
(3)elbows (including dryer connections and outside exhaust outlets). If the ductwork exceeds 20 feet (6.09 meters) or has numerous elbows, the cross section area of the ductwork must be increased in proportion to the length and number of elbows in it. In calculating duct size, the cross section area of a square or rectangular duct must be increased by twenty percent (20%) for each additional 20 feet (6.09 meters). The diameter of a round exhaust duct should be increased ten percent (10%) for each additional 15 feet (4.57 meters). Each
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