Lennox Montebello DLX Installation Instructions Manual page 14

LENNOX HEARTH PRODUCTS • MONTEBELLO
Vertical (Offset) Installation
Analyze the vent routing and determine the
quantities of vent sections and number of
elbows required. Refer to Vertical Vent
Figures and Tables on Page 16 to select
the type of vertical installation desired.
Vent sections are available in net lengths of
4-1/2 in. (114 mm), 10-1/2 in. (267 mm),
22-1/2 in. (572 mm), 34-1/2 in. (876 mm)
and 46-1/2 in. (1181 mm). Refer to the Vent
Section Length Chart on Page 13 for an aid
in selecting length combinations. Elbows are
available in 90° and 45° configurations. Refer
to Figure 20 on Page 15 for the SV8 E45 and
SV8 E90 elbow dimensional specifications.
Where required, a telescopic vent section
(SV8LA) may be used to provide the installer
with an option in installing in tight and
confined spaces or where the vent run made
up of fixed length pieces develops a joint in
a undesirable location, or will not build up to
the required length. The SV8LA Telescopic
Vent Section has an effective length of from
1-1/2 in. (38 mm) to 6-3/4 in. (171 mm). The
SV8LA is fitted with a dimpled end (identical
to a normal vent section component) and a
plain end with 3 pilot holes. Slip the dimpled
end over the locking channel end of a
standard SV8 vent component the required
distance and secure with three screws.
Maintain a minimum 1 in. (25 mm)
clearance to combustible materials for
all vertical elements. Clearances for all
horizontal elements are 3 in. (76 mm) on
top, 1 in. (25 mm) on sides and 1 in. (25
mm) on the bottom.
A. Frame ceiling opening—Use a plumb line
from the ceiling above the appliance to locate
center of the vertical run. Cut and/or frame an
opening, 13 in. x 13 in. (330 mm x 330 mm)
inside dimensions, about this center mark
(Figure 16).
Roof
Minimum
Framing
13 in.
(330 mm)
Ceiling
Framing
Figure 16
14
®
B. Attach vent components to appliance—
Secure Vent
components are unitized concentric pipe
components featuring positive twist lock
connections (see Figure 17).
All of the appliances 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.
Arrow
Appliance Collar or
Vent Section
Figure 17
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 inlet of
the four inclined channels on the collar (refer
to Figure 17). Push the vent component
against the collar 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.
The unitized design of the Secure Vent
components will engage and seal both the
inner and outer pipe without the need for
sealant or screws. If desired a #6 x 1/2 in.
screw may be used at the joint, but it is not
required as the pipe will securely lock when
twisted.
Minimum
13 in.
C. Attach vent components to each other—
(330 mm)
Other vent sections may be added to the
previously installed section in accordance
with the requirements of the vertical vent
figures and tables. To add another vent
component to a length of vent run, align the
dimpled end over the inclined channel end
of the previously installed section, adjusting
the radial alignment until the four locking
Plumb
Bob
dimples are aligned with the inlets of the four
incline channels of the previous section.
NOTE: DIAGRAMS & ILLUSTRATIONS ARE NOT TO SCALE.
DLX DIRECT VENT GAS FIREPLACES (MDLX40/45) • INSTALLATION INSTRUCTIONS
SV8 direct-vent system
®
Align the dimple (four places) of the
upper vent section with the opening
of the locking incline channel on the
lower vent section or appliance col-
lar. Twist vent component clockwise
to engage and seal until arrow and
dimple align.
Dimple
Locking Incline
Channel
Connected Vent Arrow
Sections
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 17.
D. Install firestop/spacer at ceiling—When
using Secure Vent, use SV8BF firestop/
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 ceiling, 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
in. (25 mm) clearance to combustibles,
framing members, and attic or ceiling
insulation when running vertical chimney
sections. Attic insulation shield (H3908)
may be used to obtain the required
clearances indicated here. See installation
accessories on Page 30. The gap between
the vent pipe and a vertical firestop can be
sealed with non-combustible caulking.
E. Support the vertical vent run sections—
Note: Proper venting support is very
important. The weight of the vent must not
be supported by the fireplace in any degree.
Support the vertical portion of the venting
system every 8 feet (2.4 m) above the
fireplace vent outlet.
®
Figure 18
Blocking
Support Straps
(Plumber's tape)
8 feet (2.4 m)
Maximum
1 inch (25.4
mm) minimum
clearance to
combustibles