Napoleon Fireplaces Vittoria GD19P - Manual (Page 15)

15
W415-0612 / C / 01.25.08
The shaded area within the lines represents acceptable
values for H
T
and V
T
.
For vent confi gurations requiring more than two 90° elbow
(top exit) or one 90° elbow (rear exit), the following formulas
apply:
Formula 1: H
T
< 3V
T
Formula 2: H
T
+ V
T
< 35 feet
Simple venting confi gurations
FIGURE 18
Example 7:
V
1
= 2 ft
V
2
= 1 ft
V
3
= 1.5 ft
V
T
= V
1
+ V
2
+ V
3
= 2 + 1 + 1.5 = 4.5 ft
H
1
= 6 ft
H
2
= 2 ft
H
R
= H
1
+ H
2
= 6 + 2 = 8 ft
H
O
= .03(four 90° elbows - 90°)
= .03(90 + 90 + 90 + 90 - 90) = 8.1 ft
H
T
= H
R
+ H
O
= 8 + 8.1 = 16.1 ft
H
T
+ V
T
= 16.1 + 4.5 = 20.6 ft
Formula 1: H
T
< 3V
T
3V
T
= 3 x 4.5 = 13.5 ft
16.1 > 13.5
Since this formula is not met, this vent confi guration is
unacceptable.
Formula 2:
H
T
+ V
T
< 35 feet
20.6 < 35
Since only formula 2 is met, this vent confi guration
is unacceptable and a new fi replace location or vent
confi guration will need to be established to satisfy both
formulas.
Example 8:
V
1
= 1.5 ft
V
2
= 5 ft
V
T
= V
1
+ V
2
= 1.5 + 5 = 6.5 ft
H
1
= 1 ft
H
2
= 1 ft
H
3
= 10.75 ft
H
R
= H
1
+ H
2
+ H
3
= 1 + 1 + 10.75 = 12.75 ft
H
O
= .03(three 90° elbows + one 45° elbow - 90°)
= .03(90 + 90 + 90 + 45 - 90) = 6.75 ft
H
T
= H
R
+ H
O
= 12.75 + 6.75 = 19.5 ft
H
T
+ V
T
= 19.5 + 6.5 = 26 ft
Formula 1: H
T
< 3V
T
3V
T
= 3 x 6.5 = 19.5 ft
19.5 = 19.5
Formula 2: H
T
+ V
T
< 35 feet
26 < 35
Since both formulas are met, this vent confi guration is
acceptable.
FIGURE 19
FIGURE 17
H
1
H
2
V
3
V
1
90°
90°
90°
90°
H
2
H
3
V
1
V
2
90°
45°
90°
H
1
90°
V
2
(H
T
) > (V
T
)
See graph to determine the required vertical rise V
T
for the
required horizontal run H
T
.
REQUIRED
VERTICAL
RISE IN
FEET
V
T
HORIZONTAL VENT RUN PLUS OFFSET IN FEET H
T