20
NOTE: DIAGRAMS & ILLUSTRATIONS ARE NOT TO SCALE.
Installation Instructions
901136-00 B, 05/2023
Innovative Hearth Products
Montebello® ST-B Power-Vent Direct-Vent Fireplace
D. Attach vent components to appliance.
To attach a vent component to the appliance
collar, align the dimpled end over the collar,
adjusting the radial alignment until the four
locking dimples are aligned with the inlets of
the four incline channels on the collar (refer
to Figure 18 on Page 18).
Push the vent component against the collar
until it fully engages, then twist the compo-
nent clockwise, running the dimples down
and along the incline channels until they
seat at the end of the channels. The unitized
design of the Secure Vent components will
engage and seal both the inner and outer pipe
elements with the same procedure. Sealant
and securing screws are not required.
E. Attach vent components to each other.
Other vent sections may be added to the
previously installed section in accordance
with the requirements of the vent tables.
To add another vent component to a length
of vent run, align the dimpled end of the
component over the inclined channel end of
the previously installed section, adjusting the
radial alignment until the four locking dimples
are aligned with the inlets of the four incline
channels of the previous section. Push
the vent component against the previous
section until it fully engages, then twist the
component clockwise running the dimples
down and along the incline channels until they
seat at the end of the channels. This seating
position is indicated by the alignment of
the arrow and dimple as shown in Figure
18 on Page 18.
F. Install firestop/spacer at ceiling.
When using Secure Vent, use SV4.5VF fire-
stop/spacer at ceiling joists. If there is living
space above the ceiling level, the firestop/
spacer must be installed on the bottom side
of the ceiling. If attic space is above the ceil-
ing, the firestop/ spacer must be installed
on the top side of the joist. Route the vent
sections through the framed opening and
secure the firestop/spacer with 8d nails or
other appropriate fasteners at each corner.
Remember to maintain 1" (26 mm) clear-
ance to combustibles, framing members,
and attic or ceiling insulation when running
vertical chimney sections.
G. Support the vertical run sections.
On the vertical run, support the venting
system every 8 feet (2.4m) above the fire-
place vent outlet with field provided support
straps (Plumber's tape). Attach the straps
to the vent pipe and secure to the framing
members with nails or screws. See Figure
19 on Page 18.
H. Change vent direction.
At transition from or to a horizontal/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 possibility of unlocking any of the
previously connected vent sections (see
Figures 18 and 20 on Page 18).
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 3 feet (1914 mm) along horizontal/
inclined vent runs using conventional
plumber’s tape.
See Figure 21 on Page 19.
HORIZONTAL (OUTSIDE WALL)
TERMINATION SYSTEM
See Figures 21 and 22 on Page 19 illustrating
the various horizontal venting configurations
that are possible for use with these appliances.
The table in Figure 22 on Page 19 shows each
system’s minimum and maximum vertical and
horizontal length values that can be used to
design and install the vent components in a
variety of applications.
The horizontal vent system terminates through
an outside wall. Building Codes limit or prohibit
terminating in specific areas. Refer to Figure 3
on Page 8 for location guidelines.
Secure Vent® SV4.5 direct-vent system compo-
nents are unitized concentric pipe components
featuring positive twist lock connection, (refer
to Figure 18 on Page 18). All of the appli-
ances covered in this document are fitted with
collars having locking inclined channels. The
dimpled end of the vent components fit over
the appliance collar to create the positive twist
lock connection.
A. Plan the vent run.
Analyze the vent routing and determine the
types and quantities of sections required
4-1/2" (114 mm), 10-1/2" (267 mm), 22-1/2"
(572 mm), 34-1/2" (876 mm) and 46-1/2"
(1181 mm) net section lengths are available.
Make allowances for elbows as indicated in
Figure 20 on Page 18.
Maintain a minimum 1" (26 mm) clearance
to combustibles on the vertical sections.
Clearances for the horizontal runs are; 3"
(77 mm) on top, 1" (26 mm) on sides, and
1" (26 mm) at the bottom.
B. Frame exterior wall opening.
Locate the center of the vent outlet on the
exterior wall according to the dimensions
shown in Figure 11 on Page 13.
Cut and/or frame an opening, 10-1/2" x 12-
1/8" (267 mm x 308 mm) inside dimensions,
with 7-1/2" above center and 5-5/8" below
center.
C. Frame ceiling opening.
If the vertical route is to penetrate a ceiling,
use plumb line to locate the center above
the appliance. Cut and/or frame an open-
ing, 10-1/2" x 10-1/2" (267 mm x 267 mm)
inside dimensions, about this center (refer
to Figure 17 on Page 18).
NOTICE: It is important to install
horizontal runs on a steady, (i.e., no
“dips”), slightly positive incline of
approximately 1/4" rise-per-foot (20
millimeters rise-per-meter) horizontal,
in a direction away from the fireplace.
(Slightly smaller rise-per-foot run ratios
are acceptable). Use a carpenter’s level
to measure from a constant surface, and
adjust support straps as necessary.
Installing Power Vent Termination
J. Assemble vent run to exterior wall.
If not previously measured, locate the cen-
ter of the vent on the exterior wall. Prepare
an opening as described in this manual.
Assemble the vent system to a point where
the terminus of the last section is within 8
inches of the outside wall surface where
the power vent is to be mounted (refer to
Figure 24 on Page 21).
If the terminus of the last section is not
within this distance, use the telescopic vent
section SV4.5LA, as the last vent section.
For wall thicknesses greater than that shown
in Figure 24 on Page 21, refer to Table 8
(Page 21) for the additional venting compo-
nents needed (in addition to the termination
and adaptor) for a particular range of wall
thicknesses.
K. Attach termination adaptor.
Attach the adaptor (SV4.5RCH, provided
with the power vent kit) to the vent section
telescoping vent section, or elbow, as shown
in Figures 23 and 24 on Page 21 in the same
manner as any SV4.5 vent component.