Alliance Laundry Systems 70269701R4 User Manual

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Exhaust Requirements
70269701
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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 (both pockets on stacked 
models).
The maximum allowable length venting of the same 
diameter as the exhaust thimble is 14 feet (4.3 meters) 
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 meters). Cross section area of a 
rectangular duct must be increased by 20% for each 
additional 20 feet (6.1 meters). Table 4 shows how to 
determine equivalent venting.
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 meters)
With the tumbler (both pockets on stacked models) in 
operation, airflow at any point in the duct should be at 
least 1200 feet per minute (366 meters per minute) to 
ensure that lint remains airborne. If 1200 feet per 
minute cannot be maintained, schedule a regular 
inspection and cleaning of the ductwork.
Duct 
Diameter
Equivalent Length of 
Straight Duct
6 in. (152 mm)
8 in. (203 mm)
10 in. (254 mm)
12 in. (305 mm)
14 in. (356 mm)
16 in. (406 mm)
18 in. (457 mm)
One 90° elbow = 7 ft. (2.1 m)
One 90° elbow = 9.3 ft. (2.83 m)
One 90° elbow = 11.6 ft. (3.5 m)
One 90° elbow = 14 ft. (4.3 m)
One 90° elbow = 16 ft. (4.9 m)
One 90° elbow = 18.7 ft. (5.7 m)
One 90° elbow = 21 ft. (6.4 m)
Equivalent Length (feet) = 1.17 x Duct Diameter (inches)
Table 4