www.fmiproducts.com
116235-01M
10
INSTALLATION pLANNING
There are two basic types of direct-vent
installation:
• Horizontal Termination
• Vertical Termination
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 (see
Figure 14, page 12).
1. Set fireplace in its desired location and
determine 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 through 18 on pages 12
through 14 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 supported every three feet.
Use wall straps for this purpose.
3. Use a 45° elbow to connect venting system
to fireplace flue collar. The elbow is de
-
signed to be twist-locked onto the flue collar
as described in step 2.
IMPORTANT:
Do
not attempt to alter the configuration of the
elbow by cutting, twisting, bending, etc.
4. 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.
VENTING INSTALLATION
Continued
Figure 8 - Vent Pipe Connections
Female Locking Lugs
Male
Slots
(Framing
Detail)
11
1
/
2
"
11
1
/
2
" Inside Framing
11
1
/
2
"
8
1
/
2
"
Vent Opening
Combustible Wall
Vent Opening
Noncombustible Wall
Figure 9 - Vent Opening Requirements
Center of
Hole
5. Carefully determine location where vent
pipe assembly will penetrate outside wall.
Center of hole should line up with center
line of horizontal vent pipe. Mark wall for a
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 penetrated is
constructed of noncombustible material,
such as masonry block or concrete, a 8
1
/
2
" hole with zero clearance is acceptable
(see Figure 9).
