Filter
Top Products
12
W415-0210 / E / 06.25.03
when (H
T
) > (V
T
)
Simple venting configuration (only two 90° elbows)
Example 5:
V
1
=4 ft
V
2
=1.5 ft
V
T
=
V
1
+
V
2
=
4 + 1.5 = 5.5 ft
H
1
=2 ft
H
2
=1 ft
H
3
=1 ft
H
4
=1.5 ft
H
R
=H
1
+ H
2
+ H
3
+ H
4
= 2 + 1 + 1 + 1.5 = 5.5 ft
H
O
=.03(four 90° elbows + one 45° elbow - 90°)
=.03(90 + 90 + 90 + 90 + 45 - 90) = 9.45 ft
H
T
=H
R
+ H
O
= 5.5 + 9.45 = 14.95 ft
H
T
+ V
T
= 14.95 + 5.5 = 20.45 ft
Formula 1: H
T
< 3.5V
T
3.5V
T
=
3.5 x
5.5 = 19.25 ft
14.95 < 19.25
Formula 2: H
T
+ V
T
< 24.75 feet
20.45 < 24.75
Since both formulas are met, this vent configuration is ac-
ceptable.
FIGURE 14
For vent configurations requiring more than two 90° elbows
the following formulas apply:
Formula 1: H
T
< 3.5V
T
Formula 2: H
T
+ V
T
< 24.75 feet
REQUIRED
VERTICAL
RISE IN
INCHES
HORIZONTAL VENT RUN PLUS OFFSETS IN
FEET
H
T
See graph to determine the required vertical rise V
T
for the
required horizontal run H
T
FIGURE 13
H
1
H
2
H
3
H
4
V
1
V
2
90°
90°
45°
90°
90°
V
T
The shaded area within the lines represents acceptable
values for H
T
and V
T
.
REAR EXIT / HORIZONTAL TERMINATION