Napoleon LHD45N Installation And Operating Instructions Manual page 17

NOTE: There MUST be a 25% reduction in total horizontal length (H
For vent configurations requiring more than two 90° elbows the following formulas apply:
Formula 1: H
Formula 2: H
Example:
V = 2 FT
1
V = 1 FT
2
V = 1.5 FT
3
V = V + V
T 1
H = 6 FT
1
H = 2 FT
2
H = H + H
R 1
H = .03 (four 90° elbows - 90°)
O
= .03 (360° - 90°) = 8.1 FT
H = H + H
T R
H + V = 16.1 + 4.5 = 20.6 FT
T T
Formula 1:
Since this formula is not met, this vent configuration is unacceptable.
Formula 2:
Since only formula 2 is met, this vent configuration is unacceptable and a new appliance location or vent configuration will
need to be established to satisfy both formulas.
NOTE: All vent parameters are stated for rigid venting. If using approved Wolf Steel Ltd. fl exible vent-
ing then maximum horizontal requirements are reduced by 25%.
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Simple venting configurations.
< 3V
T T
+ V < 40 feet
T T
+ V = 2 + 1 + 1.5 = 4.5 FT
2 3
= 6 + 2 = 8 FT
2
= 8 + 8.1 = 16.1 FT
O
H < 3V
T T
3V = 3 x 4.5 = 13.5 FT
T
16.1 > 13.5
H + V < 40 feet
T T
20.6 < 40
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(H ) > (V )
T T
See graph to determine the required vertical rise V
20
19
REQUIRED
VERTICAL
RISE IN
10
FEET V
T
3
0
5
HORIZONTAL VENT RUN PLUS OFFSET IN FEET H
The shaded area within the lines represents acceptable
90°
) when using fl ex vent.
T
required horizontal run H .
T
10 15 20
values for H and V
T T
90°
H
V
V
1
2
1
90°
18.1_2A
W415-0834 / D / 09.07.12
Toll-Free 1-866-667-8454
17
for the
T
25 30
T
V
3
H
2
90°