6
NOTE: DIAGRAMS & ILLUSTRATIONS ARE NOT TO SCALE.
LENNOX HEARTH PRODUCTS • MERIT PLUS
®
B-VENT GAS FIREPLACES (MPB33/35/40/45) • INSTALLATION INSTRUCTIONS
APPLIANCE AND VENT CLEARANCES
MINIMUM CLEARANCES TO COMBUSTIBLES
The appliance is approved with zero
clearance to combustible materials on
all sides. Refer to
Table 5
for minimum
clearance values. For typical installations,
see
Figure 3 on Page 5
.
Minimum Clearances
Back
1/2" (13 mm)
0 (0) from Spacers or Dimples
Sides
1/2" (13 mm)
0 (0) from Spacers or Dimples
Top Spacers
3" (76 mm)
0" (0 mm)
with standoff(s) in vertical
position
Floor
0" (0 mm)
Bottom of
Appliance
To Ceiling
64" (1626 mm)
Vent
1" (25.4 mm)
SERVICE CLEARANCES
Front
3' (0.9 m)
Table 5
NOTE: 3" (75 mm) minimum clearance is
required above any inclined vent component.
1" minimum clearance is required to the sides
of vertical vent.
Hearth Extension
- A hearth extension is not
required with this appliance. If a hearth exten-
sion is used, do not block the lower control
compartment door. Any hearth extension used
is for appearance only and does not have to
conform to standard hearth extension instal-
lation requirements.
WALL FINISHES / SURROUNDS / MANTELS
NOTE:
Combustible wall finish materials and/
or surround materials must not be allowed to
encroach the area defined by the appliance
front face (black sheet metal).
Never allow
combustible materials to be positioned in
front of or overlapping the appliance face.
Refer to
Figure 36 on Page 21
for clearance
recommendations and requirements.
Figures 6 and 7
illustrate the areas surrounding
the fireplace where clearances are an issue. The
outer edge of the metal trim on only one side
of the fireplace may abutt a perpendicular wall.
For this type of installation, the other side of the
fireplace must be a flat wall to allow for proper
air flow and burner operation.
Combustible materials may project beyond one
or both sides of the fireplace opening when
these materials are kept within the "Safe Zone"
illustrated in
Figure 6
.
3 1/2 in.
(89 mm)
Top View of
Fireplace
Combustible materials
may project beyond
either side of the
fireplace opening as
long as they are kept
within the shaded
“Safe Zone” area.
At 0 in. minimum
side wall clearance,
one combustible
wall can project to
any length.
45
o
Mantel Leg,
Trim, or Wall
Figure 6 - Clearance References
0” Clearance
to Combustible
Side Wall
Ceiling
64"
(1626 mm)
Bottom of Fireplace
Figure 7 - Wall Clearances
Non-combustible materials, such as surrounds
and other appliance trim, may be installed on the
appliance face with these exceptions:
They must not cover any portion of the removable
glass panel, louvers, or control compartment.
Vertical installation clearances to combustible
mantels vary according to the depth of the
mantel (see
Figure 7
). Mantels constructed of
non-combustible materials may be installed
at any height above the appliance opening;
however, do not allow anything to hang below
the fireplace hood.
Minimum clearance requirements include any
projections such as shelves, window sills,
mantels, etc. above the appliance.
NOTE:
We recommend the use of high
temperature paint (rated 175 °F, or higher)
on the underside of the mantel.
12 (305) MANTEL
10 (254) MANTEL
8 (203) MANTEL
6 (152) MANTEL
4 (102) MANTEL
4
(102)
14
(356)
12
(305)
10
(254)
2 (51) MANTEL
TOP OF
APPLIANCE
6
(152)
NOTE - Hood shown as positioned in louvered
front model. The hood position in the flush
faced front model is lower than shown.
8
(203)
MANTEL CLEARANCES
Inches (mm)
Figure 8 - Minimum Mantel Clearances