Napoleon Fireplaces Castlemore GDS26N - Manual (Page 9)

9
W415-0607 / A / 01.18.08
90°
90°
90° H
1
V
2
H
2
V
1
Simple venting confi guration
(only one 90° elbow)
For vent confi gurations requiring more than one 90° elbow,
the following formulas apply:
Formula 1: H
T
< V
T
Formula 2: H
T
+ V
T
< 40 feet
Example 1:
V
1
= 3 ft
V
2
= 8 ft
V
T
= V
1
+ V
2
= 3 + 8 = 11 ft
H
1
= 2.5 ft
H
2
= 2 ft
H
R
= H
1
+ H
2
= 2.5 + 2 = 4.5 ft
H
O
= .03(three 90° elbows - 90°) = .03(270° - 90°) = 5.4 ft
H
T
= H
R
+ H
O
= 4.5 + 5.4 = 9.9 ft
H
T
+ V
T
= 9.9 + 11 = 20.9 ft
Formula 1: H
T
< V
T
9.9 < 11
Formula 2: H
T
+ V
T
< 40 feet
20.9 < 40
Since both formulas are met, this vent confi guration is
acceptable.
FIGURE 8
HORIZONTAL VENT RUN PLUS OFFSET IN FEET H
T
The shaded area within the lines represents acceptable
values for H
T
and V
T
.
for the following symbols used in the venting calculations
and examples are:
> - greater than
> - equal to or greater than
< - less than
< - equal to or less than
H
T
- total of both horizontal vent lengths ( H
R
) and offsets
( H
O
) in feet
H
R
- combined horizontal vent lengths in feet
H
O
- offset factor: .03(total degrees of offset - 90° *) in
feet
V
T
- combined vertical vent lengths in feet
feet inches
1° 0.03 0.5
15° 0.45 6.0
30° 0.9 11.0
45° 1.35 16.0
90° * 2.7 32.0
* the fi rst 90° offset has a zero value and is shown in the
formula as -90°
DEFINITIONS ELBOW VENT LENGTH VALUES
TOP EXIT / HORIZONTAL TERMINATION
FIGURE 7
VERTICAL
RISE
IN FEET
V
T
0
2.5 5 7.5 10 12.5 15
40
10
20
30
17.5 20
39
(H
T
) < (V
T
)
See graph to determine the required vertical rise V
T
for the
required horizontal run H
T
.