Tips about the ductwork

Ducting

–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.

–Rigid metal or flexible aluminum ducting is preferred. Flexible foil ducting may move and bounce due to the high airflow of the dryer. This could lead to a thumping or grinding noise.

–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.

–Do not assemble the duct with screws or other fastening devices that extend into the duct and catch lint.

–The shorter the exhaust ductwork, 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 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 duct length.

A larger duct diameter helps to reduce friction. Therefore duct diameter should be increased if longer duct lengths are required.