Table II
Effective duct length
Internal diameter
0 - 20 m
20 - 30 m
30 - 43 m
43 - 60 m
100 mm
110 mm
120 mm
130 mm
Flexible ducting has been used for the
following example. See Table I for addi-
tional duct length factors for other
types of ducting.
Example:
Side connection, left . . . . . . . . . 2.00 m
Length (L) . . . . . . . . . . . . . . . . . 1.20 m
Lower radius (R) . . . . . . . . . . . . 0.50 m
Height (H) . . . . . . . . . . . . . . . . . 1.00 m
Upper radius (R) . . . . . . . . . . . . 0.50 m
Wall pipe with louvred vent . . . . 3.80 m
Effective duct length . . . . . . . . . 9.00 m
Result:
A duct diameter of 100 mm is adequ-
ate since the effective length is less
than 20 m as specified in Table II.
Installation - venting
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