Simple venting configurations.
See graph to determine the required vertical rise
V
T
for the
required horizontal run
H
T
.
HORIZONTAL VENT RUN PLUS OFFSET IN FEET (METERS)H
T
The shaded area within the lines represents acceptable
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:
= 2FT (0.6m) + 1FT (0.3m) + 1.5FT (0.5m) = 4.5 FT (1.4m)
+ H
2
= 6FT (1.8m) + 2FT (0.6m) = 8 FT (2.4m)
= .03 (four 90° elbows - 90°)
= .03 (360° - 90°) = 8.1 FT (2.5m)
+ H
O
= 8FT (2.4m) + 8.1FT (2.5m) = 16.1FT (4.9m)
= 16.1FT (4.9m) + 4.5FT (1.4m) = 20.6FT (6.3m)
3.5 V
T
= 3FT (0.9m) x 4.5FT (1.4m) = 13.5 FT (4.1m)
16.1FT (4.9m) < 13.5 FT (4.1m)
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9
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V
3
H
2
V
2
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Formula 2: H
T
+ V
T
< 40 FT (12.2m)
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
need to be established to satisfy both formulas.
+ V
2
= 1.5FT (0.5m)+ 5FT (1.5m) = 6.5 FT (2m)
+ H
2
+ H
3
= 1FT (0.3m) + 1FT (0.3m) + 10.75FT (3.3m) = 12.75FT (3.9m)
= .03 (three 90° elbows + one 45° elbow - 90°)
= .03 (270° + 45° - 90°) = 6.75 FT (2.1m)
+ H
O
= 12.75FT (3.9m) + 6.75FT (2.1m) = 19.5 FT (5.9m)
= 19.5FT (5.9m) + 6.5FT (2m) = 26 FT (7.9m)
3 V
T
= 3FT (0.9m) x 6.5FT (2m) = 19.5FT (5.9m)
19.5FT (5.9m) = 19.5FT (5.9m)
26 FT (7.9m) < 40 FT (12.2m)
Since both formulas are met, this vent configuration is acceptable.