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125077-01D
10
INSTALLATION PLANNING
There are two basic types of direct vent
installation:
• Horizontal Termination
• Vertical Termination
Outside air flex installation is required for
both horizontal and vertical installation (see
page 13).
Horizontal Termination Installation
IMPORTANT:
Horizontal square terminations
require only inner portion of wall firestop. Hori
-
zontal installations using round termination
require exterior portion of wall firestop.
1. Set fireplace in its desired location and de
-
termine the route your horizontal venting
will take. Do not secure fireplace until all
venting has been installed. Some instal
-
lations require sliding fireplace in and out
of position to make final venting connec
-
tions. Figures 14 and 15 on page 12 show
different configurations for venting with
horizontal termination that will help you
decide which application best suits your
installation. Check to see if wall studs or
roof rafters are in the path of your desired
venting route. If they are, you may want
to adjust location of fireplace.
2. Direct vent pipe sections and components
are designed with special twist-lock con
-
nections.
Twist-Lock Procedure:
Female ends of
pipes have locking lugs (indentations).
These lugs will slide straight into match
-
ing slots on male ends of adjacent pipes.
Push pipe sections together and twist
one section clockwise approximately one-
quarter turn until sections are fully locked
(see Figure 8).
Note: Horizontal runs of vent must be sup-
ported every three feet. Use wall straps
for this purpose.
3. Assemble desired combination of pipe
and elbows to fireplace flue collar. If there
are long portions of venting run, pre-as
-
sembled pipe sections may be installed
as subassemblies for convenience.
4. Carefully determine location where vent
pipe assembly will penetrate outside wall.
VENTING INSTALLATION
Continued
Figure 8 - Vent Pipe Connections
Female
Locking Lugs
Male
Slots
Figure 9 - Vent Opening Requirements
Center
of Hole
Center of hole should line up with center
line of horizontal vent pipe. Mark wall for
an 11
1
/
2
" x 11
1
/
2
" square hole. Cut and
frame square hole in exterior wall where
vent will be terminated. If wall being pen
-
etrated is constructed of noncombustible
material, such as masonry block or con
-
crete, a 8
1
/
2
" hole with zero clearance is
acceptable (see Figure 9).
(Framing
Detail)
11
1
/
2
"
11
1
/
2
" Inside Framing
11
1
/
2
"
8
1
/
2
"
Vent Opening
Combustible Wall
Vent Opening
Noncombustible Wall
