NOTE: DIAGRAMS & ILLUSTRATIONS NOT TO SCALE.
13
Maintain a minimum 1" (25 mm) clearance
to combustible materials for all vertical
vent elements.
Clearances for horizontal vent elements are
1" (25 mm) at the sides and 1" (25 mm) on
the bottom. Clearances above horizontal
vent elements are 3" (76 mm) for all models
and all applications.
Exception: Clearance
is 5" (127 mm) for MPLDV35, MPLDV40 &
MPLDV45, when the center line of the hori-
zontal run is less than 48" (1219 mm) above
the fireplace top wrapper surface.
Framing Dimensions for Roof
Pitch
C
D
0/12
10-1/2 in.
10-1/2 in.
(267 mm)
(267 mm)
6/12
10-1/2 in.
12 in.
(267 mm)
(305 mm)
12/12
10-1/2 in.
17-3/4 in.
(267 mm)
(451 mm)
Figure 19
Figure 20
Figure 22
Figure 21
If the vent system extends more than 5' (1.5
m) above the roof flashing, stabilizers may be
necessary. Additional screws may be used at
section joints for added stability. Guide wires
may be attached to the joint for additional
support on multiple joint configurations.
I. Continue installation of horizontal/inclined
sections - Continue with the installation of the
straight vent sections in horizontal/inclined
run as described in Step E. Install support
straps every 5' (1.52 m) along horizontal/
inclined vent runs using conventional plumber’s
tape. It is very important that the horizontal/
inclined run be maintained in a straight (no
dips) and slightly elevated plane in a direc-
tion away from the fireplace 1/4" per foot (20
mm per meter) which is ideal, though rise per
foot run ratios that are smaller are acceptable
all the way down to at or near level.
It is important to maintain the required clear-
ances to combustibles at the top and bottom
for all horizontal/inclined runs.
Loop the tape around the vent, securing the
ends of the tape to the framing. If desired,
sheet metal screws #6 x 1/2" length may be
used to secure the support straps to the vent
pipe. Refer to
Figure 17.
H. Change vent direction to horizontal/in-
clined run - At transition from or to a horizon-
tal/inclined run, install the SV4.5E45 and
SV4.5E90 elbows in the same manner as the
straight vent sections. The elbows feature a
twist section to allow them to be routed about
the center axis of their initial collar section to
align with the required direction of the next
vent run element. Twist elbow sections in a
clockwise direction only so as to avoid the
possiblity of unlocking any of the previously
connected vent sections. See
Figure 18.
Figure 18
SV4.5E90
(90
°
Elbow)
8-1/8"
(206 mm)
Swivel Joint
(360
°
swivel)
4-13/16"
(122 mm)
SV4.5E45
(45
°
Elbow)
Swivel Joint
(360
°
swivel)
C
D
Storm
Collar
H. Frame roof opening - Identify location for
vent at the roof. Cut and/or frame opening per
Roof Framing Chart and
Figure 19.
L. Install the vertical termination - The final step
involves installation of the SV4.5CGV-1 Vertical
Termination. Extend the vent sections to the
height as shown in the "Vertical vent termination
section" on page 6. The SV4.5CGV-1 Vertical
Termination (
Figure 22 ) installs in the exact
same fashion as any other Secure Vent section.
Align the termination over the end of the previ-
ously installed section, adjusting the radial align-
ment until the four locking dimples of the termi-
nation are aligned with the inlets of the four
incline channels of the last vent section. Push the
termination down until it fully engages, then twist
the termination clockwise running the dimples
down and along the incline channels until they
seat at the end of the channels.
J. Install the roof flashing - Extend the vent
sections through the roof structure. Install the
roof flashing over the vent section and posi-
tion such that the vent column rises vertically
(use carpenters level) (
Figure 20 ). Nail along
perimeter to secure flashing or adjust roofing
to overlap the flashing edges at top and sides
only and trim where necessary. Seal the top
and both sides of the flashing with waterproof
caulking.
K. Install the storm collar - Install the storm
collar, supplied with the flashing, over the
vent/flashing joint. See
Figure 21. Loosen
the storm collar screw. Slide collar down until
it meets the top of the flashing. Tighten the
adjusting screw. Apply non-combustible caulk-
ing or mastic around the circumference of the
joint to provide a water tight seal.
