Elbow Vent Length Values; Top Exit Horizontal Termination - Napoleon B30NTR-1 Installation And Operation Manual

2.6

elbow vent length values

FEET INCHES
1° 0.03 0.5
15° 0.45 6.0
30° 0.9 11.0
45° 1.35 16.0
90°* 2.7 32.0
* The fi rst 90° offset has a zero value and is shown in the formula as - 90°
2.7

top exit horizontal termination

Simple venting confi guration (only one 90° elbow)
For vent confi gurations requiring more than one 90° elbow, the following formulas apply:
Formula 1: H < V
T T
Formula 2: H + V < 40 feet (12.2m)
T T
Example:
V = 3 FT (0.9m)
1
V = 8 FT (2.4m)
2
V = V + V = 3 FT (0.9m ) + 8 FT (2.4m) = 11 FT (3.4m)
T 1 2
H = 2.5 FT (0.8m)
1
H = 2 FT (0.6m)
2
H = H + H = 2.5 FT (0.8m) + 2 FT (0.6m) = 4.5 FT (1.4m)
R 1 2
H = .03 (three 90° elbows - 90°) = .03 (270° - 90°) = 5.4 FT (1.7m)
O
H = H + H = 4.5 FT (1.4m) + 5.4 FT (1.6m) = 9.9 FT (3m)
T R O
H + V = 9.9 FT (3m) + 11 FT (3.4m) = 20.9 FT (6.4m)
T T
Formula 1: H < V
T
9.9 FT (3m) < 11 FT (3.4m)
Formula 2: H + V
T
20.9 FT (6.4m) < 40 FT (12.2m)
Since both formulas are met, this vent confi guration is acceptable.
MILLIMETERS
12.7
152.4
279.4
406.4
812.8
(H
39 (11.9)
REQUIRED
VERTICAL
RISE IN FEET
(METERS)V
T
T
< 40 FT (12.2m)
T
venting requirements
) < (V )
T T
See graph to determine the required vertical
rise V for the required horizontal run H
T
40 (12.2)
30 (9.1)
20 (6.1)
10 (3.1)
0
2.5 5 7.5
(0.8) (1.5) (2.3)
HORIZONTAL VENT RUN PLUS OFFSET IN FEET
(METERS) H
The shaded area within the lines represents
acceptable values for H
90°
T
10 12.5 15 17.5 20
(3.1) (3.8) (4.6) (5.3) (6.1)
T
and V
T T
90°
H
2
V
2
90°
H
1
V
1
W415-1768 / C / 03.08.19
EN
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15