14
3.7
HORIZONTAL TERMINATION
EN
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
Formula 2: H
Example:
= 3 FT (0.9m)
V
1
= 8 FT (2.4m)
V
2
= V
+ V
V
T
1
= 2.5 FT (0.8m)
H
1
= 2 FT (0.6m)
H
2
= H
+ H
H
R
1
2
= .03 (three 90° elbows - 90°) = .03 (270° - 90°) = 5.4 FT (1.6m)
H
O
= H
+ H
H
T
R
+ V
= 9.9 FT (3m) + 11 FT (3.4m) = 20.9 FT (6.4m)
H
T
T
Formula 1:
Formula 2:
Since both formulas are met, this vent confi guration is acceptable.
W415-1334 / 06.10.14
REQUIRED
VERTICAL
RISE IN FEET
(MEETERS) V
H
T
Min. V
= 48"; H
T
< V
T
T
+ V
< 40 feet (12.2m)
T
T
= 3 FT (0.9m) + 8 FT (2.4m) = 11 FT (3.4m)
2
= 2.5 FT (0.8m) + 2 FT (0.6m) = 4.5 FT (1.4m)
= 4.5 FT (1.4m) + 5.4 FT (1.6m) = 9.9 FT (3m)
O
H
< V
T
T
9.9 FT (3m) < 11 FT (3.4m)
H
+ V
< 40 FT (12.2m)
T
T
20.9 FT (6.4m) < 40 FT (12.2m)
(H
) < (V
)
T
T
See graph to determine the required vertical
40 (12.2)
39 (11.9)
30 (9.1)
20 (6.1)
T
10 (3.1)
4 (1.2)
0
HORIZONTAL VENT RUN PLUS OFFSET IN
= V
The shaded area within the lines represents
T
should start at 48"
T
rise V
for the required horizontal run H
T
2.5
5
7.5
10
12.5
(0.8)
(1.5)
(2.3)
(3.1)
(3.8)
FEET (METERS) H
acceptable values for H
90°
V
2
90°
H
90°
V
1
.
T
15
17.5
20
(4.6)
(5.3)
(6.1)
T
and V
T
T
H
2
1