Speed Queen TMB796C Individual Venting, Manifold Venting, Duct, MUST, Figure, Straight Duct, =42 feet (12.8 m), Exhaust Requirements, Equivalent Length of

Exhaust Requirements

Individual Venting

For maximum efficiency and performance, it is preferred to exhaust tumbler(s) individually to the outdoors.

IMPORTANT: At no point may the cross sectional area of installed venting be less than the cross sectional area of the exhaust outlet of the tumbler.

The exhaust duct must be designed so the static back pressure measured 12 inches (305 mm) from the exhaust outlet does not exceed the maximum allowable pressure specified on the installation sticker on the rear of the tumbler.

NOTE: Static back pressure must be measured with the tumbler running.

The maximum allowable length venting is 14 feet (4.3 m) and two 90° elbows or equivalent. If the equivalent length of a duct required for an installation exceeds the maximum allowable equivalent length, the diameter of a round duct must be increased by 10% for each additional 20 feet (6.1 m). Cross section area of a rectangular duct must be increased by 20% for each additional 20 feet (6.1 m). Refer to Table 2 to determine equivalent venting.

Duct	Equivalent Length of
Diameter	Straight Duct

8 in. (203 mm) One 90° elbow = 9.3 ft. (2.83 m) 10 in. (254 mm) One 90° elbow = 11.6 ft. (3.5 m) 12 in. (305 mm) One 90° elbow = 14 ft. (4.3 m)

14 in. (356 mm) One 90° elbow = 16 ft. (4.9 m) 16 in. (406 mm) One 90° elbow = 18.7 ft. (5.7 m) 18 in. (457 mm) One 90° elbow = 21 ft. (6.4 m)

Equivalent Length (feet) = 1.17 x Duct Diameter (inches)

Table 2

Example: A 12 inch (305 mm) diameter duct’s equivalent length of 14 feet (4.3 m) of duct and two 90° elbows is:

Equivalent Length = 14 feet + (2) 90° elbows

=14 feet + 14 feet + 14 feet

=42 feet (12.8 m)

With the tumbler in operation, airflow at any point in the duct should be at least 1200 feet per minute (366 m/min.) to ensure that lint remains airborne. If 1200 feet per minute cannot be maintained, schedule monthly inspections and cleaning of the ductwork.

Manifold Venting

While it is preferable to exhaust tumblers individually to the outdoors, a main collector duct may be used if it is sized according to Figure 16 and Figure 17. This illustration indicates minimum diameters, and should be increased if the collector length exceeds 14 feet (4.3

m)and two 90° elbows. The diameter of a round duct must be increased by 10% for each additional 20 feet (6.1 m). Cross sectional area of a rectangular or square duct must be increased 20% for each additional 20 feet (6.1 m). Refer to Table 3 and Table 4 tab to determine equivalent ducting sizing. The collector duct may be rectangular or square in cross section, as long as the area is not reduced. Provisions MUST be made for lint removal and cleaning of the collector duct.

The vent collector system must be designed so the static back pressure measured 12 inches (305 mm) from the exhaust outlet does not exceed the maximum allowable pressure of 0.5 W.C.I. (1.3 mbar) as specified on the installation sticker on the rear of tumbler. Static back pressure must be measured with all tumblers vented into the collector operating.

NOTE: Never connect a tumbler duct at a 90° angle to the collector duct. Refer to Figure 14. Doing so will cause excessive back pressure, resulting in poor performance. Never connect two tumbler exhaust ducts directly across from each other at the point of entry to the collector duct.

T438I

Figure 14

M414905