Lennox Montebello MDLX40IN 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" (114 mm), 10-1/2" (267
mm), 22-1/2" (572 mm), 34-1/2" (876 mm) and
46-1/2" (1181 mm). Refer to the Vent Section
Length Chart on Page 13 for an aid in select-
ing 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" (38 mm) to
6-3/4" (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" (25 mm) clearance
to combustible materials for all vertical ele-
ments. Clearances for all horizontal elements
are 3" (76 mm) on top, 1" (25 mm) on sides
and 1" (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" x 13" (330 mm x 330 mm) inside
dimensions, about this center mark (Figure 16).
Roof
Minimum
Framing
(330 mm)
Ceiling
Framing
Figure 16
14
B. Attach vent components to appliance -
Secure Vent
nents 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 compo-
nents 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
Minimum
without the need for sealant or screws. If desired
13"
a #6 x 1/2" screw may be used at the joint, but
(330 mm)
it is not required as the pipe will securely lock
when twisted.
C. Attach vent components to each other - Other
13"
vent sections may be added to the previously
installed section in accordance with the require-
ments of the vertical vent figures and tables.
To add another vent component to a length of
Plumb
Bob
vent run, align the dimpled end 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.
NOTE: DIAGRAMS & ILLUSTRATIONS ARE NOT TO SCALE.
DLX DIRECT VENT GAS FIREPLACES (MDLX40/45) • INSTALLATION INSTRUCTIONS
®
SV8 direct-vent system compo-
®
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" (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.
Support Straps
(Plumber's tape)
8 feet (2.4 m)
Maximum
1" (25.4 mm)
minimum
clearance to
combustibles
Figure 18
Blocking