venting requirements
EN
2.8
vertical termination
Simple venting configurations.
For vent configurations 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
= 5 FT (1.5m)
1
V
= 10 FT (3.1m)
2
V
= V
+ V
= 5FT (1.5m) + 10FT (3.1m) = 15 FT (4.6m)
T
1
2
H
= 3 FT (0.9m)
1
H
= 2.5 FT (0.8m)
2
H
= H
+ H
= 3FT (0.9m) + 2.5FT (0.8m) = 5.5 FT (1.7m)
R
1
2
H
= .03 (three 90° elbows - 90°)
O
= .03 (270° - 90°) = 5.4 FT (1.6m)
H
= H
+ H
= 5.5FT (1.7m) + 5.4FT (1.6m) = 10.9 FT (3.3m)
T
R
O
H
+ V
= 10.9 FT (3.3m) + 15 FT (4.6m) = 25.9 FT (7.9m)
T
T
Formula 1:
H
T
10.9 FT (3.3m) < 15 FT (4.6m)
Formula 2:
H
T
25.9 FT (7.9m) < 40 (12.2m)
Since both formulas are met, this vent configuration is acceptable.
16
W415-1337 / B / 09.25.18
< V
T
+ V
< 40 FT (12.2m)
T
(H
) < (V
)
T
T
See graph to determine the required vertical rise V
required horizontal run H
40 (12.2)
30 (9.1)
REQUIRED
VERTICAL
20 (6.1)
RISE IN FEET
(METERS)V
T
10 (3.1)
3 (0.9)
0
HORIZONTAL VENT RUN PLUS OFFSET IN FEET (METERS) H
The shaded area within the lines represents acceptable
values for H
.
T
5
10
15
20
(1.5)
(3.1)
(4.6)
(6.1)
and V
T
T
V
2
90°
H
2
V
1
H
90°
1
18.6A
for the
T
T
90°