Empire Comfort Systems DVLXG75BP90N-1 Installer's Manual page 38

EFFECTIVE LENGTH PRE FAN IS CALCULATED BY THE
FOLLOWING EQUATION:
3 Way
Splitter
Flexible Ducting
Equation 1
Effective length = Vertical Run Up + (2 x Vertical Run Down) +
Horizontal Run + (3 x # of 90° bends) + (1.5 x # of 45° bends) +
length of wire reinforced ducting
Fireplace A₁
Height
3ft 5in 2ft
Vertical Run Up = ( Fireplace Height + B1 ) = 3ft. 5in + 10ft =
13ft. 5in.
Vertical Run Down = 0ft.
Horizontal Run = (A1 + A2) = (2ft. + 6ft.) = 8ft
Number of Bends = 2
Effective Length = Vertical Run Up + (2 x Vertical Run Down) +
Horizontal Run + (3 x # of 90° bends) + (1.5 x # of 45° bends) +
length of wire reinforced ducting
Effective Length = 13ft. 5in + (2 x 0 ft.) + 8ft. + (3 x 2 bends) +
(1.5 x 0 bends) + 1ft.
Effective Length = 28ft. 5in.
38
DUCT VENT INSTALLATION
Duct Fan
Assembly
D
C
10" Wire
8" Wire
Reinforced
Reinforced
Flexible Ducting
EXAMPLE 1
A₂ B₁ C Bends
6ft 10ft 1ft
A
8" Duct Joiner
8" Aluminium Flexible
Ducting or Solid Pipe
Total
Effective
Length
2 28ft 5in
R
B
R
A
FIREPLACE