Simple venting configurations.
Simple venting configurations.
For vent configurations requiring more than two 90° elbows (top exit) or one 90° elbow (rear exit), the following
For vent configurations requiring more than two 90° elbows (top exit) or one 90° elbow (rear exit), the following
formulas apply:
formulas apply:
Formula 1: H
< 3 V
Formula 1: H
< 3 V
T
T
Formula 2: H
T
+ V
< 40 feet (12.2m)
T
Formula 2: H
+ V
< 40 feet (12.2m)
T
T
T
T
Example:
Example:
V
= 2 FT (0.6m)
V
= 2 FT (0.6m)
1
V
1
= 1 FT (0.3m)
V
= 1 FT (0.3m)
2
V
= 1.5 FT (0.5m)
2
V
= 1.5 FT (0.5m)
3
V
= V
+ V
+ V
= 2FT (0.6m) + 1FT (0.3m) + 1.5FT (0.5m) = 4.5 FT (1.4m)
3
V
= V
+ V
+ V
= 2FT (0.6m) + 1FT (0.3m) + 1.5FT (0.5m) = 4.5 FT (1.4m)
T
1
2
3
H
T
= 6 FT (1.8m)
1
2
3
H
= 6 FT (1.8m)
1
H
1
= 2 FT (0.6m)
H
= 2 FT (0.6m)
2
H
= H
+ H
= 6FT (1.8m) + 2FT (0.6m) = 8 FT (2.4m)
2
H
= H
+ H
= 6FT (1.8m) + 2FT (0.6m) = 8 FT (2.4m)
R
1
2
H
= .03 (four 90° elbows - 90°)
R
1
2
H
= .03 (four 90° elbows - 90°)
O
O
= .03 (360° - 90°) = 8.1 FT (2.5m)
= .03 (360° - 90°) = 8.1 FT (2.5m)
H
= H
+ H
= 8FT (2.4m) + 8.1FT (2.5m) = 16.1FT (4.9m)
H
= H
+ H
= 8FT (2.4m) + 8.1FT (2.5m) = 16.1FT (4.9m)
T
R
O
H
+ V
= 16.1FT (4.9m) + 4.5FT (1.4m) = 20.6FT (6.3m)
T
R
O
H
+ V
= 16.1FT (4.9m) + 4.5FT (1.4m) = 20.6FT (6.3m)
T
T
T
T
Formula 1:
H
< 3.5 V
Formula 1:
H
< 3.5 V
T
T
3.5 V
T
3.5 V
T
16.1FT (4.9m) < 13.5 FT (4.1m)
16.1FT (4.9m) < 13.5 FT (4.1m)
Since this formula is not met, this vent configuration is unacceptable.
Since this formula is not met, this vent configuration is unacceptable.
Formula 2:
H
+ V
< 40 FT (12.2m)
Formula 2:
H
+ V
< 40 FT (12.2m)
T
T
16.1FT (4.9m) < 13.5 (4.1m)
T
T
16.1FT (4.9m) < 13.5 (4.1m)
Since only formula 2 is met, this vent configuration is unacceptable and a new fireplace location or vent configuration will
Since only formula 2 is met, this vent configuration is unacceptable and a new fireplace location or vent configuration will
need to be established to satisfy both formulas.
need to be established to satisfy both formulas.
Example:
V
= 1.5 FT (0.5m)
1
V
= 5 FT (1.5m)
2
V
= V
+ V
= 1.5FT (0.5m)+ 5FT (1.5m) = 6.5 FT (2m)
T
1
2
H
= 1 FT (0.3m)
1
H
= 1 FT (0.3m)
2
H
= 10.75 FT (3.3m)
3
H
= H
+ H
+ H
= 1FT (0.3m) + 1FT (0.3m) + 10.75FT (3.3m) = 12.75FT (3.9m)
R
1
2
3
H
= .03 (four 90° elbows + one 45° elbow - 90°)
O
= .03 (360° + 45° - 90°) = 6.75 FT (2.1m)
H
= H
+ H
= 12.75FT (3.9m) + 6.75FT (2.1m) = 19.5 FT (5.9m)
T
R
O
H
+ V
= 19.5FT (5.9m) + 6.5FT (2m) = 26 FT (7.9m)
T
T
Formula 1:
H
< 3 V
T
T
3 V
= 3FT (0.9m) x 6.5FT (2m) = 19.5FT (5.9m)
T
19.5FT (5.9m) = 19.5FT (5.9m)
Formula 2:
H
+ V
< 40 FT (12.2m)
T
T
26 FT (7.9m) < 40 FT (12.2m)
Since both formulas are met, this vent configuration is acceptable.
(H
) > (V
(H
T
T
REQUIRED
REQUIRED
VERTICAL
VERTICAL
RISE IN
RISE IN
FEET
FEET
(METERS)V
(METERS)V
HORIZONTAL VENT RUN PLUS OFFSET IN FEET (METERS)H
HORIZONTAL VENT RUN PLUS OFFSET IN FEET (METERS)H
= 3FT (0.9m) x 4.5FT (1.4m) = 13.5 FT (4.1m)
T
= 3FT (0.9m) x 4.5FT (1.4m) = 13.5 FT (4.1m)
T
)
) > (V
)
T
T
See graph to determine the required vertical rise V
See graph to determine the required vertical rise V
required horizontal run H
required horizontal run H
20 (6.1)
20 (6.1)
19 (5.8)
19 (5.8)
10 (3.1)
10 (3.1)
3 (0.9)
3 (0.9)
T
T
0
5
10
0
5
10
(1.5)
(3.1)
(1.5)
(3.1)
The shaded area within the lines represents acceptable
The shaded area within the lines represents acceptable
values for H
values for H
90°
90°
V
V
1
H
1
H
1
90°
H
2
45°
V
1
H
1
90°
for the
for the
T
.
T
.
T
T
15
20
25
30
15
20
25
(4.6)
(6.1)
(7.6)
(9.1)
(4.6)
(6.1)
(7.6)
(9.1)
and H
and H
T
T
T
T
90°
90°
V
V
3
V
H
V
H
2
2
2
2
1
90°
90°
90°
90°
18.2_2B
18.2_2B
H
3
18.2_3A
W415-1613 / C / 12.22.16
W415-1613 / D / 09.20.17
21
21
EN
EN
30
T
T
3
V
2
90°