Installation
900960-00C, 06/2019
Innovative Hearth Products
DRT3500-C Series Direct-Vent Gas Fireplaces
29
Vertical Vent Figures/Tables
NOTE: Secure Vent
®
rigid vent pipe is shown in the figures; Secure Flex
®
flexible vent pipe may also be used.
NOTE: Rise per foot run ratios are acceptable all the way to level. For best results, maintain the horizontal/inclined
run in a straight (no dips), slightly elevated plane of approximately 1/4” per 1 ft (20 mm per 1 m).
NOTE: SV4.5VF (Secure Vent), SF4.5VF (Secure Flex) firestop/spacer must be used anytime vent pipe passes
through a combustible floor or ceiling. SV4.5HF (Secure Vent), SF4.5HF (Secure Flex)firestop/spacer must be used
anytime vent pipe passes through a combustible wall.
NOTE: Two (2) 45° elbows may be used in place of one (1) 90° elbow. The same rise to run ratios, as shown in the
venting figures for 90° elbows, must be followed if 45° elbows are used.
WARNING
Do NOT join separate sections of concentric flexible vent pipe.
Figure 23 - Top Vent—Straight
Table 16 - Rear Vent—One 90° Elbow
Ceiling
firestop/
spacer
SV4.5VF *
When using
Secure Flex
®
,
use ceiling
firestop/spacer
SF4.5VF.
*
60 ft (18.3 m)
maximum
H Maximum
V Minimum
feet
meters
feet
meters
2
0.610
1
0.305
4
1.219
2
0.610
6
1.829
3
0.914
8
2.438
4
1.219
Ceiling firestop/
spacer SV4.5VF *
When using Secure Flex
®
,
use ceiling firestop/spacer
SF4.5VF.
*
H
V
Install the U-shaped vent restrictor in any vent run with more than
6 ft of vertical rise. See
Page 22
for more information.
Minimum 6 ft and maximum of 60 ft of vertical
venting.
V + H = 60 ft (18.3 m) maximum
H = 8 ft (2.4 m) maximum
Install the U-shaped vent restrictor in any vent run with more than 6
ft of vertical rise. See
Page 22
for more information.
If 8 ft of (H) horizontal vent run is needed, then 4 ft
(straight section) minimum of (V) vertical vent will be
required.
This table shows a 1 (V) to 2 (H) ratio. For every 1 ft of
(V) vertical, you are allowed 2 ft of (H) horizontal run, up
to a maximum horizontal run of 8 ft.
Minimum 6 ft of vertical venting.
