Miele T 8003 Operating and installation manual - Page 38

Installation Tips about the duct work - Check with your local building code to determine the maximum allowable duct length. - Only use rigid or flexible metal duct for exhausting. Non-metallic flexible hose should not be used, it is a potential fire hazard. - In the United Stated foil-type flexible ducts should only be used if identified for use by the manufacturer as compliant with the Outline for Clothes Dryer Transition Duct, Subject ANSI/UL 2158A. In Canada, only flexible metal (foil-type) ducts specifically identified for use by the manufacturer should be used. - For best drying results avoid extra long ducting with too many bends, angles or tight corners. - The shorter the exhaust duct work, the more efficient the dryer will be. Expelled air is slowed down in the ducts due to friction against the inner walls. The shorter and smoother the inner walls are, the less friction will be created. - An elbow or bend creates more friction than a straight duct. An additional duct length factor must be added for each elbow or bend (see the "Additional duct lengths" table). This factor expresses the resistance of the bend in terms of a straight length of duct. The additional length factor is then added to the existing duct to give the effective length. A larger duct diameter helps reduce friction. Therefore the duct diameter and length should be increased simultaneously. - Do not assemble the duct with screws or other fastening devices that extend into the duct and catch lint. 34