Lennox LSM40EN-2, LSM45MN-2, LSM45EN-2, LSM45MP-2, LSM40MP-2 User Manual

INSTALLATION INSTRUCTIONS

AVERTISSEMENT : Assurez-vous de bien suivre les
instructions données dans cette notice pour réduire au
minimum le risque d’incindie ou d’explosion ou pour
éviter tout dommage matériel, toute blessure ou la mort.

WARNING: If the information in these instructions
is not followed exactly, a fire or explosion may
result, causing property damage, personal injury,
or death.

WARNING /AVERTISSEMENT/AVISO

• HOT GLASS WILL CAUSE
BURNS.

• DO NOT TOUCH GLASS
UNTIL COOLED.

• NEVER ALLOW CHILDREN
TO TOUCH GLASS.

• UNE SURFACE VITRÉE CHAUDE
PEUT CAUSER DES BRÛLURES.

• LAISSER REFROIDIR LA SURFACE
VITRÉE AVANT D'Y TOUCHER.

• NE PERMETTEZ JAMAIS À UN ENFANT
DE TOUCHER LA SURFACE VITRÉE.

• EL VIDRIO CALIENTE
CAUSARÁ QUEMADURAS.

• USTED DEBE NUNCA
TOCAR EL VIDRIO CALIENTE.

• LOS NIÑOS DEBEN NUNCA
TOCAR EL VIDRIO.

- Do not store or use gasoline or other flammable

vapors and liquids in the vicinity of this or any other
appliance.

- WHAT TO DO IF YOU SMELL GAS:

• Do not try to light any appliance.

• Do not touch any electrical switch; do not use any

phone in your building.

• Immediately call your gas supplier from a

neighbor’s phone. Follow the gas supplier’s
instructions.

• If you cannot reach your gas supplier, call the fire

department.

- Installation and service must be performed by a
qualified installer, service agency or the gas supplier.

- Ne pas entreposer ni utilizer d’essence ni d’autres vapeurs
ou liquides inflammables dans le voisinage de cet appareil
ou de tout autre appareil.

- QUE FAIRE SI VOUS SENTEZ UNE ODEUR DE GAZ :

• Ne pas tenter d’allumer d’appareil.

• Ne touchez à aucan interrupteur. Ne pas vous servir des

téléphones se trouvant dans le bâtiment où vous trouvez.

• Appelez immédiatement votre fournisseur de gaz depuis

un voisin. Suivez les instructions du fournisseur.

• Si vous ne pouvez rejoindre le fournisseur de gaz,

appelez le service des incindies.

- L’installation et l’entretien doivent être assurés par un
installateur ou un service d’entretien qualifié ou par le
fournisseur de gaz.

Montebello®
Direct Vent Gas Fireplaces

MODELS

P/N 850026M Rev. G 06/2011

This manual is one of a set of two supporting this product.
Refer to P/N 875027M for Care and Operation Instructions.

Ce manuel est disponible en francais, simplement
en faire la demande. Numéro de la pièce 850026CF.

INSTALLER: Leave this manual with the appliance.
CONSUMER: Retain this manual for future reference.

INSTALLATEUR : Laissez cette notice avec l'appareil.
CONSOMMATEUR : Conservez cette notice pour
consultation ultérieure.

This appliance may be installed in an aftermarket permanently located, manufactured home (USA only) or mobile
home, where not prohibited by local codes. This appliance is only for use with the type of gas indicated on the rating
plate. This appliance is not convertible for use with other gases unless a certified kit is used.

LSM40MN-2
LSM40MP-2

OTL Report No. 116-F-22-5

MILLIVOLT:

LSM45MN-2
LSM45MP-2

Portland

US

ELECTRONIC:

LSM40EN-2
LSM45EN-2

LENNOX HEARTH PRODUCTS • MONTEBELLO® DV GAS FIREPLACES (LSM40/45MN-2, LSM40/45MP-2, LSM40/45EN-2) • INSTALLATION INSTRUCTIONS

TABLE OF CONTENTS

Packaging .........................................Page 2

Introduction ......................................Page 2

General Information ..........................Page 2

Massachusetts and New York

Requirements ................................Page 4

Cold Climate Insulation .....................Page 5

Manufactured Home Requirements ..Page 5

Location ............................................Page 5

Vent Termination Clearances ............Page 6

Minimum Clearances to Combustibles Page 8

Detailed Installation Steps .................Page 9

Typical Installation Sequence ...........Page 9

Step 1. Framing ...............................Page 9

Fireplace and Framing Specifications ..Page 10

Step 2. Routing Gas Line ................Page 11

Proper Sizing of Gas Line ..................Page 11

Step 3. Install the Vent System .......Page 12

Vertical Termination Systems ............Page 13

Vent Section Length Chart ................Page 13

Vertical Vent Tables and Figures ........Page 16

Horizontal Termination System .........Page 17

Horizontal Vent Tables and Figures ...Page 19

Step 4. Field Wiring .........................Page 21

Step 5. Removing Glass Door

Frame Assembly ...........................Page 22

Step 6. Connecting Gas Line ...........Page 22

Step 7. Checking Appliance

Operation ......................................Page 23

Step 8. Installing Logs and Panels ..Page 24

Step 9. Installing Glass Door ..........Page 26

Step 10. Burner Adjustments ............Page 26

Finishing Requirements ....................Page 28

Step 11. Attaching Safety-in-

Operation Warnings .....................Page 29

Installation Accessories ....................Page 30

Gas Conversion Kits .........................Page 31

Please read and understand these
instructions before beginning your

installation.

PACKAGING

The assembled vented gas fireplace is pack­aged with:

1 - one envelope located in the firebox contain-

ing the literature package, which consists of
the care and operation manual, installation
instructions, safety in operation warning
labels and warranty

2- one bag of glowing embers and volcanic

stone

3 - one of the following brick liner kits:

a. Brick Liner Kit, Rustic
b. Brick Liner Kit, Herringbone
c. Brick Liner Kit, Old Cottage
d. Brick Liner Kit, Black.
e. Brick Liner Kit, Red Rustic
f. Brick Liner Kit, Red Herringbone

4 - one of the following log sets:

a. Birch Log set

b. Oak Log set
5 - pull screen
6 - door modesty shield

INTRODUCTION

The Millivolt appliances are designed to operate
on natural or propane gas and have a millivolt
gas control valve with piezo ignition system.

The Electronic appliances are designed to
operate on natural or propane gas and have a
electronic intermittent pilot ignition system. No
external electrical power is required to operate
these units.

These vented gas fireplaces are sealed com­bustion gas fireplaces designed for residential
applications.

Use Only These Approved Vent Components

- These fireplaces are designed, tested and
listed for operation and installation with,
the following (8" inner and 11" outer) vent
components only:

• Secure Vent™ Direct Vent System Compo-

nents manufactured by Security Chimneys
International.

These approved vent system components are
labeled for identification. DO NOT use any
other manufacturer’s vent components with
these appliances.

GENERAL INFORMATION

WARNING

Young children should be care­fully supervised when they are
in the same room as the appli­ance. Toddlers, young children
and others may be susceptible
to accidental contact burns. A
physical barrier is recommended
if there are at risk individuals in
the house. To restrict access to
a fireplace or stove, install an
adjustable safety gate to keep
toddlers, young children and
other at risk individuals out of
the room and away from hot
surfaces.

AVERTISSEMENT

Les jeunes enfants devraient être
surveillés étroitement lorsqu’ils
se trouvent dans la même pièce
que l’appareil. Les tout petits,
les jeunes enfants ou les adultes
peuvent subir des brûlures s’ils
viennent en contact avec la sur­face chaude. Il est recommandé
d’installer une barrière physique
si des personnes à risques habi­tent la maison. Pour empêcher
l’accès à un foyer ou à un poêle,
installez une barrière de sécu­rité; cette mesure empêchera les
tout petits, les jeunes enfants et
toute autre personne à risque
d’avoir accès à la pièce et aux
surfaces chaudes.

Children and adults should be alerted to the
hazards of high surface temperature and
should stay away to avoid burns or clothing
ignition.

Les enfants et les adultes devraient être infor­més des dangers que posent les températures
de surface élevées et se tenir à distance afin
d’éviter des brûlures ou que leurs vêtements
ne s’enflamment.

DO NOT ATTEMPT TO ALTER OR MODIFY
THE CONSTRUCTION OF THE APPLIANCE OR
ITS COMPONENTS. ANY MODIFICATION OR
ALTERATION MAY VOID THE WARRANTY,
CERTIFICATION AND LISTINGS OF THIS UNIT.

2

LENNOX HEARTH PRODUCTS • MONTEBELLO® DV GAS FIREPLACES (LSM40/45MN-2, LSM40/45MP-2, LSM40/45EN-2) • INSTALLATION INSTRUCTIONS

WARNING

Improper installation, adjust­ment, alteration, service or
maintenance can cause injury
or property damage. Refer to
this manual. For assistance or
additional information consult
a qualified installer, service
agency or the gas supplier.

WARNING

Failure to comply with these
installation instructions will result
in an improperly installed and
operating appliance, voiding its
warranty. Any change to this appli­ance and/or its operating controls
is dangerous.

WARNING

Clothing or other flammable
material should not be placed
on or near the appliance.

AVERTISSEMENT

On ne devrait pas placer de
vêtements ni d’autres matières
inflammables sur l’appareil ni à
proximité.

WARNING

Any safety screen or guard
removed for servicing the appli­ance must be replaced prior to
operating the appliance.

AVERTISSEMENT

Tout écran ou protecteur retiré
pour permettre l’entretien de
l’appareil doit être remis en
place avant de mettre l’appareil
en marche.

WARNING

Improper installation or use of
this appliance can cause serious
injury or death from fire, burns,
explosion or carbon monoxide
poisoning.

Note: Installation and repair should be done
by a qualified service person. The appliance
should be inspected before use and at least
annually by a professional service person.
More frequent cleaning may be required due
to excessive lint from carpeting, bedding
material, etcetera. It is imperative that control
compartments, burners and circulating air
passageways of the appliance be kept clean.

Remarque : L’installation et la réparation
devrait être confiées à un technicien qualifié.
L’appareil devrait faire l’objet d’une inspec­tion par un technicien professionnel avant
d’être utilisé et au moins une fois l’an par la
suite. Des nettoyages plus fréquents peuvent
être nécessaires si les tapis, la literie, et
cetera produisent une quantité importante de
pous-sière. Il est essentiel que les comparti­ments abritant les commandes, les brûleurs et
les conduits de circulation d’air de l’appareil
soient tenus propres.

Do not use these appliances if any part
has been under water. Immediately call a
qualified, professional service technician
to inspect the appliance and to replace
any parts of the control system and any
gas control which have been under water.

Ne pas se servir de cet appareil s'il a été
plongé dans l'eau, complètement ou en
partie. Appeler un technicien qualifié pour
inspecter l'appareil et remplacer toute partie
du système de contrôle et toute commande
qui ont été plongés dans l'eau.

Only trim kit(s) supplied by the manufacturer
shall be used in the installation of this ap­pliance.

Seules les trousses de garniture fournies
par le fabricant doivent être utilisées pour
l’installation de cet appareil.

These appliances comply with National Safety
Standards and are tested and listed by OMNI­Test Laboratories, Inc. (Report No. 116-F-22-5)
to ANSI Z21.50 (in Canada, CSA-2.22), and
CAN/CGA-2.17-M91 in both USA and Canada,
as vented gas fireplaces.

Both millivolt and electronic versions of
these appliances are listed by OMNI-Test
Laboratories for installation in bedrooms and
mobile homes.

Misc. Codes / Standards -

The Installation must conform to local codes.
In the absence of local codes, installation must
comply with the current National Fuel Gas Code,

ANSI Z223.1. (In Canada, the current CAN/
CSA-B149.1 installation code).

The appliance, when installed, must be electri­cally grounded in accordance with local codes
or, in the absence of local codes, with the

National Electrical Code, ANSI/NFPA 70 - latest
edition, or the Canadian Electrical Code, CSA
C22.1 - latest edition.

Provide adequate clearances around air open­ings and adequate accessibility clearance for
service and proper operation. Never obstruct
the front openings of the appliance.

These appliances are designed to operate on
natural or propane gas only. The use of other
fuels or combination of fuels will degrade
the performance of this system and may be
dangerous.

These fireplaces are designed as supplemental
heaters. Therefore, it is advisable to have an
alternate primary heat source when installed
in a dwelling.

Millivolt Models - The millivolt appliances are
manually controlled and feature a spark igniter
(piezo) that allows the appliance's pilot gas to be
lit without the use of matches or batteries. This
system provides continued service in the event
of a power outage.

The Millivolt models come standard with the
manually-modulated gas valve; flame appear­ance and heat output can be controlled at the

gas valve. The BTU Input for these appliances

is shown in Table 1.

Electronic Models - The electronic appliances
are manually controlled and feature an electronic
intermittent pilot ignition system. External elec­trical power is required to operate these units.

Electronic models come standard with a
manually-modulated gas valve; flame appear­ance and heat output can be controlled at the

gas valve. The BTU Input for these appliances

is shown in Table 1.

Input (BTU/HR) - All Models

Model No. Input (BTU/Hr)

Natural Gas

LSM40-2 40,000 to 50,000
LSM45-2 47,000 to 60,000

Propane Gas

LSM40-2 40,000 to 50,000
LSM45-2 48,000 to 60,000

Table 1

3

LENNOX HEARTH PRODUCTS • MONTEBELLO® DV GAS FIREPLACES (LSM40/45MN-2, LSM40/45MP-2, LSM40/45EN-2) • INSTALLATION INSTRUCTIONS

H
I

L

O

W

TPTH TP TH

P

I

L

O

T

P

I

L

O

T

O

N

it

O

F

F

Hi / Lo
Variable Flame
Height Adjustment

Manifold
Pressure
Gauge Port

Inlet Pressure
Gauge

Port

Main Gas

Control Knob
Off / Pilot / On

Pilot
Adjustment
Screw

IN

OUT

Gas Supply Inlet

Gas Outlet to Burner

HI

LO

Gas Pressure - All Models

Tables 2 and 3 show the appliances' inlet and
manifold gas pressure requirements:

4

Inlet Gas Supply Pressure

(all models)

Fuel # Minimum Maximum

Natural Gas

Propane

5.5" WC

(1.37 kPa)

11.0" WC

(2.74 kPa)

10.5" WC

(2.61 kPa)

13.0" WC

(3.23 kPa)

Table 2

Manifold Gas Supply Pressure

(all models)

Fuel # Low High

Natural

Gas

Propane

(Lo) 2.2" WC

(.55 kPa)

(Lo) 6.3" WC

(1.57 kPa)

(Hi) 3.5" WC

(.87 kPa)

(Hi) 10.0" WC

(2.49 kPa)

Table 3

Test gauge connections are provided on the
front of the millivolt and electronic gas control
valve (identified IN for the inlet and OUT for the
manifold side).

Propane tanks are at pressures that will cause
damage to valve components. Verify that the
tanks have step down regulators to reduce the
pressure to safe levels.

These appliances must be isolated from the
gas supply piping system (by closing their
individual manual shut-off valve) during any
pressure testing of the gas supply piping
system at test pressures equal to or less
than 1/2 psig (3.5 kPa).

These appliances and their individual shut-off
valves must be disconnected from the gas
supply piping system during any pressure
testing of that system at pressures greater
than 1/2 psig (3.5 kPa).

These appliances must not be connected to a
chimney or flue serving a separate solid fuel
burning appliance.

Orifice Sizes - Sea Level To High Altitude
(All Models)

These appliances are tested and approved for
installation at elevations of 0-4500 feet (0-1372
meters) above sea level, using the standard
burner orifice sizes (marked with an "*" in Table

4). For elevations above 4500 feet, contact your
gas supplier or qualified service technician.

Deration - At higher elevations, the amount

of BTU fuel value delivered must be reduced

by either:

• Using gas that has been derated by the gas

company.

• Changing the burner orice to a smaller size

as regulated by the local authorities having

jurisdiction and by the (USA) National Fuel

Gas Code NFPA 54/ANSI Z223.1 - latest

edition or, in Canada, the CAN/CSA-B149.1

codes - latest edition.

Install the appliance according to the regulations

of the local authorities having jurisdiction and,

in the USA, the National Fuel Gas Code NFPA
54 / ANSI Z223.1 - latest edition or , in Canada,

the CAN/CSA-B149.1- latest edition.

NOTE: Flame appearance will diminish 4% per
thousand feet.

Burner Orifice Sizes

Elevation 0-4500 feet ( 0-1372 meters)

Model Nat.Gas

drill size (inches)

LSM40-2 .1405" (#28)*

• H2286

LSM45-2 .161" (#20)*

• H2288

Table 4

* Standard size installed at factory

• Part /Cat. Number

Propane

drill size (inches)

.086" (#44)*

• H2287

.093" (#42)*

• H4816

Gas Valve Diagrams

See Figure 1 for Millivolt models and Figure 2
For Electronic Models.

Figure 1 - SIT Millivolt Gas Valve

NOTE: DIAGRAMS & ILLUSTRATIONS ARE NOT TO SCALE.

Gas Supply Inlet

Inlet Pressure
Gauge Port

Manifold
Pressure
Gauge Port

Gas Outlet to Burner

Hi / Lo
Variable Flame
Height
Adjustment

Pilot
Adjustment
Screw

Figure 2 - SIT Electronic Gas Valve

REQUIREMENTS FOR THE COMMON­WEALTH OF MASSACHUSETTS

These fireplaces are approved for installation in
the US state of Massachusetts if the following
additional requirements are met:

• Install this appliance in accordance with

Massachusetts Rules and Regulations 248
C.M.R.

• Installation and repair must be done by a

plumber or gas fitter licensed in the Com­monwealth of Massachusetts.

• The exible gas line connector used shall

not exceed 36 inches (92 centimeters) in
length.

• The individual manual shut-off must be a

T-handle type valve.

Massachusetts Horizontal Vent Requirements

In the Commonwealth of Massachusetts, hori­zontal terminations installed less than seven
(7) feet above the finished grade must comply
with the following additional requirements:

• A hard wired carbon monoxide detector

with an alarm and battery back-up must be
installed on the floor level where the gas
fireplace is installed. The carbon monoxide
detector must comply with NFPA 720, be
ANSI/UL 2034 listed and be ISA certified.

• A metal or plastic identication plate must

be permanently mounted to the exterior of
the building at a minimum height of eight (8)
feet above grade and be directly in line with
the horizontal termination. The sign must
read, in print size no less than one-half (1/2)

inch in size, GAS VENT DIRECTLY BELOW.
KEEP CLEAR OF ALL OBSTRUCTIONS.

NEW YORK CITY, NEW YORK (MEA)

Installation of these fireplaces are approved for
installation in New York City in the US state
of New York.

LENNOX HEARTH PRODUCTS • MONTEBELLO® DV GAS FIREPLACES (LSM40/45MN-2, LSM40/45MP-2, LSM40/45EN-2) • INSTALLATION INSTRUCTIONS

Drywall

Top Of Fireplace
Opening

Non-Combustible

HORIZONTAL VENT

VERTICAL VENT

HORIZONTAL VENT

VERTICAL VENT

COLD CLIMATE INSULATION

For cold climate installations, seal all cracks
around your appliance with noncombustible
material and wherever cold air could enter
the room. It is especially important to insulate

Cross Corner

Application

outside chase cavity between studs and under
floor on which appliance rests, if floor is above
ground level. Gas line holes and other open­ings should be caulked or stuffed with unfaced
fiberglass insulation.

If the fireplace is being installed on a cement

Room Divider

Application

Recessed

Application

Island

Application

slab in cold climates, a sheet of plywood or
other raised platform can be placed underneath
to prevent cold transfer to the fireplace and into
the room. It also helps to sheetrock inside
surfaces and tape for maximum air tightness

and caulk firestops.

MANUFACTURED HOME
REQUIREMENTS

Flat

Application

Application

Flat on Wall

This appliance may be installed in an aftermarket
permanently located, manufactured home and
must be installed in accordance with the manu­facturer's instructions and the Manufactured
Home Construction and Safety Standard, Title
24 CFR, Part 3280, in the United States, or the
Standard for Installation in Mobile Homes, CAN/
CSA Z240 MH Series, in Canada.

Cet appareil peut être installé cómme du matéri­el d'origine dans une maison préfabriquée (É.U.
seulement) ou mobile et doit être installé selon
les instructions du fabricant et conformément
à la norme Manufactured Home Constructions
and Safety, Title 24 CFR, Part 3200 aux Unis ou
à la norme Can/CSA-Z240 Série MM, Maisons
mobiles au Canada.

This appliance is only for use with the type of gas
indicated on the rating plate. This appliance is
not convertible for use with other gases, unless
a certified kit is used.

Cet appareil doit être utilisé uniquement avec le
type de gaz indiqué sur la plaque signalétique.
Cet appareil ne peut être converti à d'autres gaz,
sauf si une trousse de conversion est utilisée.

CAUTION: Ensure that the cross members
are not cut or weakened during installation.
The structural integrity of the manufactured
home floor, wall, and ceiling / roof must be
maintained.

CAUTION: This appliance must be grounded to
the chassis of the manufactured home in ac­cordance with local codes or in the absence of
local codes, with the National Electrical Code
ANSI / NFPA 70 - latest edition or the Canadian
Electrical Code CSA C22.1 - latest edition.

When the unit is installed with one side flush with a wall,
the wall on the other side of the unit must not extend
beyond the front edge of the unit.

Figure 3 - Typical Installation

LOCATION

In selecting the location, the aesthetic and
functional use of the appliance are primary
concerns. However, vent system routing to
the exterior and access to the fuel supply are
also important.

Due to high temperatures, the appliance
should be located out of traffic and away from
furniture and draperies (Figure 3).

En raison des températures élevées, l’appareil
devrait être installé dans un endroit où il y a
peu de circulation et loin du mobilier et des
tentures (Figure 3).

The location should also be free of electrical,
plumbing or other heating/air conditioning
ducting.

These direct-vent appliances are uniquely
suited for installations requiring a utility shelf
positioned directly above the fireplace. Util­ity shelves like these are commonly used for
locat-ing television sets and decorative plants.

Be aware that this is a heat producing ap­pliance. Objects placed above the unit are
exposed to elevated temperatures.

Do not insulate the space between the ap­pliance and the area above it (see Figure 8

on Page 8).

The minimum height from the base of the appli­ance to the underside of combustible materials
used to construct a utility shelf in this fashion
is shown in Figure 8 on Page 8.

The appliance should be mounted on a fully
supported base extending the full width and
depth of the unit. The appliance may be located
on or near conventional construction materials.
However, if installed on combustible materials,
such as carpeting, vinyl tile, etc., a metal or
wood barrier covering the entire bottom surface
must be used.

NOTE: DIAGRAMS & ILLUSTRATIONS ARE NOT TO SCALE.

5

LENNOX HEARTH PRODUCTS • MONTEBELLO® DV GAS FIREPLACES (LSM40/45MN-2, LSM40/45MP-2, LSM40/45EN-2) • INSTALLATION INSTRUCTIONS

3"

(76 mm)

Termination Kit

Combustible Projection

greater than 2-1/2 inches in length

Horizontal Vent Termination Clearances

Combustible Projection

2-1/2 inches or less in length

24"

(610 mm)

Ventilated Or

Unventilated Soffit

12

X

Roof Pitch is X/12

2 FT
MIN.

2 FT MIN.

Lowest

Discharge

Opening

H*

*H = MINIMUM HEIGHT FROM ROOF TO
LOWEST DISCHARGE OPENING OF VENT

TERMINATION HEIGHTS FOR VENTS ABOVE

FLAT OR SLOPED ROOFS

Horizontal Overhang

Vertical
Wall

Vent

Termination

Storm Collar

Concentric

Vent Pipe

Flashing

1 inch (25.4 mm) Minimum
Clearance to Combustibles

VENT TERMINATION CLEARANCES

These instructions should be used as a guide­line and do not supersede local codes in any
way. Install vent according to local codes,
these instructions, the current National Fuel
Gas Code (ANSI-Z223.1) in the USA or the cur­rent standards of CAN/CSA-B149.1 in Canada.

Vertical Vent Termination Clearances

Terminate multiple vent terminations according
to the installation codes listed above. Also see
Figure 4.

Terminate single vent caps relative to building
components according to Figure 5.

Vertical Vent Termination Clearances

The vent / air intake termination clearances
above the high side of an angled roof is as
shown in the following chart:

Termination Heights For Vents

Above Flat Or Sloped Roofs
Ref. NFPA 54 / ANSI Z223.1

Roof Pitch * Feet * Meters

Flat to 6/12 1.0 0.3
6/12 to 7/12 1.25 0.38
7/12 to 8/12 1.5 0.46
8/12 to 9/12 2.0 0.61

9/12 to 10/12 2.5 0.76
10/12 to 11/12 3.25 0.99
11/12 to 12/12 4.0 1.22
12/12 to 14/12 5.0 1.52
14/12 to 16/12 6.0 1.83
16/12 to 18/12 7.0 2.13
18/12 to 20/12 7.5 2.29
20/12 to 21/12 8.0 2.44

Figure 5

12”

(305mm)

Minimum

Horizontal Vent Termination Clearances

Figure 4 - Multiple Terminations

6

The horizontal vent termination must have a minimum of 3" (76 mm) clearance to any overhead

combustible projection of 2-1/2" (64 mm) or less (see Figure 6). For projections exceeding

2-1/2" (64 mm), see Figure 7. For additional vent location restrictions refer to Figure 7 on Page 7.

See Figure 30 on Page 18 for the recess allowances,
into exterior walls, of the square horizontal terminations.

Figure 6 - Side Elevation View

NOTE: DIAGRAMS & ILLUSTRATIONS ARE NOT TO SCALE.

LENNOX HEARTH PRODUCTS • MONTEBELLO® DV GAS FIREPLACES (LSM40/45MN-2, LSM40/45MP-2, LSM40/45EN-2) • INSTALLATION INSTRUCTIONS

EXTERIOR HORIZONTAL VENT TERMINATION CLEARANCE REQUIREMENTS

NOTE: Local Codes Or Regulations May Require
Different Clearances.

NOTE: Location Of The Vent Termination Must Not
Interfere With Access To The Electrical Service.

3 ft.

X

A



3 ft.

Exterior Wall

Horizontal

Termination

B

V

L

X

= Air Supply Inlet

* See Item D in the Text Below.

*18”

24"

Inside Corner

Center Line

of Termination

18”

36"

DETAIL D

F

V

Ventilated Soffit

V

Fixed

Closed

Window

V

C

A

= Vent Terminal

V

Inside

Corner Detail

G

V

A

= 9" in U.S.



A

= 12" in Canada

B

C

C

C

Operable

V

Window

B

B

= Area where Terminal is NOT permitted

B



A

J

Minimum Clearances Canadian Installation * US Installation **

A = Clearance above grade, veranda, porch, deck
or balcony.

B = Clearance to window or door that may be opened. 6 in. (15.2 cm) for appliances < 10,000 BTU/hr (3kW),

C = Clearance to permanently closed window 12 inches (305 mm) recommended to prevent window

12 inches (30 cm) * 12 inches (30 cm) **

12 in. (30 cm) for appliances > 10,000 BTU/hr (3kW) and <
100,000 BTU/hr (30kW), 36 inches (91 cm) for appliances
> 100,000 BTU/hr (30kW)*

condensation

H

E

D

M

I

X

V

K

6 in. (15.2 cm) for appliances < 10,000 BTU/hr (3kW),
9 in. (23 cm) for appliances > 10,000 BTU/hr (3kW) and <
50,000 BTU/hr (15kW), 12 inches (30 cm) for appliances
> 50,000 BTU/hr (15kW)*

9 inches (229 mm) recommended to prevent window
condensation

V

D = Vertical clearance to ventilated soffit located

24 inches (61.0 cm) 24 inches (61.0 cm)
above the terminal within a horizontal distance of
36 in. (91.4cm) from the center line of the terminal

E = Clearance to unventilated soffit 24 inches (61.0 cm) 24 inches (61.0 cm)
F = Clearance to outside corner 5 inches (12.7 cm) 5 inches (12.7 cm)
G = Clearance to inside corner 36" (91.4 cm) 24 inches (61.0 cm)
H = Clearance to each inside of center line extended

above meter / regulator assembly

3 feet (91 cm) within a height of 15 feet above the meter /

regulator assembly *

3 feet (91 cm) within a height of 15 feet above the meter
/ regulator assembly **

I = Clearance to service regulator vent outlet 3 feet (91 cm) * 3 feet (91 cm) **

J = Clearance to non-mechanical air supply inlet
to building or the combustion air inlet to any other
appliance

6 in. (15.2 cm) for appliances < 10,000 BTU/hr (3kW), 12

in. (30 cm) for appliances > 10,000 BTU/hr (3kW) and <

100,000 BTU/hr (30kW), 36 inches (91 cm) for appliances

> 100,000 BTU/hr (30kW)*

6 in. (15.2 cm) for appliances < 10,000 BTU/hr (3kW), 9
in. (23 cm) for appliances > 10,000 BTU/hr (3kW) and <
50,000 BTU/hr (15kW), 12 inches (30 cm) for appliances
> 50,000 BTU/hr (15kW)*

K = Clearance to mechanical air supply inlet 6 feet (1.83 meters) * 3 feet (91 cm) above, if within 10 feet (3 m) horizontally**

L = Clearance above paved sidewalk or paved

7 feet (2.13 m) ‡ 7 feet (2.13 m) ‡
driveway located on public property

M = Clearance under veranda, porch, deck or

18 in. (46.0 cm) * ‡ 18 in. (46.0 cm) ** ‡
balcony

* In accordance with the current CSA-B149.1 National Gas and B149.2 Propane Installation Code - Latest Editions.

** In accordance with the current ANSI Z223.1 / NFPA 54 National Fuel Codes - Latest Edition.
‡ A vent shall not terminate directly above a sidewalk or paved driveway which is located between two single family dwellings and serves both dwellings.
*‡ Only permitted if veranda, porch, deck or balcony is fully open on a minimum 2 sides beneath the floor.

Figure 7

NOTE: DIAGRAMS & ILLUSTRATIONS ARE NOT TO SCALE.

7

LENNOX HEARTH PRODUCTS • MONTEBELLO® DV GAS FIREPLACES (LSM40/45MN-2, LSM40/45MP-2, LSM40/45EN-2) • INSTALLATION INSTRUCTIONS

17"

14"

8-1/4”

45°

12"

5"

12 (305)

10 (254)

8 (203)

6 (152)

4 (102)

7

(178)

17

(432)

15

(381)

13

(330)

2 (51)

9

(229)

11

(279)

MINIMUM CLEARANCES TO COMBUSTIBLES

The appliance is approved with zero clearance to combustible materials
on all sides (as detailed in Table 5), with the following exception: When

the unit is installed with one side flush with a wall, the wall on the
other side of the unit must not extend beyond the front edge of the
unit. In addition, when the unit is recessed, the side walls surrounding

the unit must not extend beyond the front edge of the unit (see Figure 3).

Combustible Shelf Height -

Top Vent - with 2 Feet Vertical Vent and One 90 Degree Elbow

Model Secure Vent
LSM40-2 *84-1/16 (2135)
LSM45-2 89-1/16 (2252)

* Includes 3” clearance to combustibles (required above vent components)

Inches (millimeters)

APPLIANCE MINIMUM CLEARANCES*

Inches (millimeters)

Sides 1/2 (13), 0 (0) Spacers **

Top Spacers 0 (0)

Floor 0 (0)

Back 1/2 (13), 0 (0) Spacers

Bottom of Appliance To Ceiling 69 (1743)

Vent 3 (76)

Top* / 1 (25.4) Sides & Bottom

SERVICE CLEARANCES Feet (meters)

Front 3 feet (0.9 meters)

Table 5

*Note: 3 in. (75 mm) above any horizontal/inclined vent component.

**Note: See Page 9, Step 1 for clearance requirements to the nailing
flange located at each side of the unit and any screw heads adjacent to it.

The appliance should be mounted on a fully supported base extending
the full width and depth of the unit. The appliance may be located on
or near conventional construction materials. However, if installed on
combustible materials, such as carpeting, vinyl tile, etc., a metal or wood
barrier covering the entire bottom surface must be used.

Shelf Height

To provide for the lowest possible shelf surface, the venting attached to
the top vent should be routed in a way to minimize obstructions to the
space above the appliance. Do not insulate the space between the ap­pliance and the area above it (see Figure 8). The minimum height from
the base of the appliance to the underside of combustible materials used
to construct a utility shelf in this fashion is shown in Figure 8.

Wall Finishes / Surrounds / Mantels

Do not insulate the
space between the
appliance and the
area above it.

Figure 8

Figure 9

Combustible Materials
Allowed In Shaded Area
"Safe Zone"

Shelf Height

(see table)

Shelf Above Fireplace With Top Venting

MANTEL

MANTEL

MANTEL

MANTEL

MANTEL

MANTEL

Top of Appliance

Top View of

Fireplace

2 Foot Vertical
Vent (Min.)

MANTEL

CLEARANCES

Inches (mm)

Fireplace

(side view)

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. See Figure 10 and Figure
53 on Page 28.

Non-combustible materials, such as surrounds and other appliance trim,
may be installed on the appliance front face with these exceptions: they
must not cover any portion of the removable glass panel.

Vertical installation clearances to combustible mantels vary according
to the depth of the mantel. See Figure 9. Mantels constructed of non­combustible materials may be installed at any height above the appliance
opening.

NOTE: We recommend the use of high temperature paint (rated 175° F
or higher) on the underside of the mantel.

8

NOTE: DIAGRAMS & ILLUSTRATIONS ARE NOT TO SCALE.

Figure 10

Side
Wall

Minimum Distance to
Protected Side Wall

Side
Wall

Minimum Distance to
Unprotected Side Wall

LENNOX HEARTH PRODUCTS • MONTEBELLO® DV GAS FIREPLACES (LSM40/45MN-2, LSM40/45MP-2, LSM40/45EN-2) • INSTALLATION INSTRUCTIONS

Step 3. (Page 12) Install the vent system and

WARNING

Failure to position the parts in
accordance with these diagrams
or failure to use only parts specifi­cally approved with this appliance
may result in property damage or
personal injury.

AVERTISSEMENT

Risque de dommages ou de
blessures si les pièces ne sont
pas installées conformément à
ces schémas et ou si des pièces
autres que celles spécifiquement
approuvées avec cet appareil sont
utilisées.

DETAILED INSTALLATION STEPS

The appliance is shipped with all gas controls
and components installed and pre-wired.

1. Remove the shipping carton, exposing the
front glass door on the valve access side.

2. Using a Phillips screwdriver, unfasten two (2)
screws located at the top of the glass frame
(see Figure 49). Tilt the top of the glass
frame away from the unit. Lift it carefully
off the bottom door track and set the door
aside, protecting it from inadvertent damage.

Step 4. (Page 21) Field Wiring
a. Millivolt and Electronic Appliances –

b. Electronic Appliances – Connect 120

Step 5. (Page 22) Remove glass door assem-

Step 6. (Page 22) Make connection to gas

Step 7. (Page 23) Verifying appliance opera-

Step 8. (Page 24) Install ceramic panels, logs

Step 9. (Page 26) Install glass door assembly.
Step 10. (Page 26) Adjust burner to ensure

Step 11. (Page 29) Attach Safety in Operation

Step 1. FRAMING

Frame these appliances as illustrated in Figure
12 on Page 10, unless the appliance is to be
installed in a corner. See Figure 13 on Page
11 for corner framing installations. All framing

details must allow for a minimum clearance to
combustible framing members as shown in
Table 5 on Page 8.

If the appliance is to be elevated above floor
level, a solid continuous platform must be
constructed below the appliance.

exterior termination.

The operating control switch is factory
installed.

Vac electrical power to the appliance
receptacle.

bly.

supply.

tion.

and glowing embers.

proper flame appearance.

Warnings.

Use Bottom Flange For
5/8” Thick Drywall

Left Side Front Corner of Fireplace Shown

(Right Side Requirements the Same)

Unit Being Secured By Its Nailing Flanges

To The Framing

Note: The nailing flanges, combustible members
and screw heads located in areas directly adjacent
to the nailing flanges, are EXEMPT from the 1/2”
clearance to combustible requirements for the
firebox outer wrapper. Combustible framing may be
in direct contact with the nailing flanges and may
be located closer than 1/2” from screw heads and
the firebox wrapper in areas adjacent to the nailing
flanges. Frame the opening to the exact dimensions
specified in the framing details of this manual.

Unit Being Secured by Its Nailing

Flanges to the Framing

Figure 11

TYPICAL INSTALLATION SEQUENCE

The typical sequence of installation is outlined
below. However, each installation is unique and
may result in variations to the steps described.

See the Page numbers references in the follow­ing steps for detailed procedures.

Step 1. (Page 9) Construct the appliance

framing. Position the appliance within
the framing and secure with nailing
brackets.

Step 2. (Page 11) Route gas supply line to

the right side.

Headers may be in direct contact with the
appliance top spacers but must not be sup­ported by them or notched to fit around them.
All construction above the appliance must be
self-supporting, DO NOT use the appliance for
structural support.

The fireplace should be secured to the side
framing members using the unit's nailing
flanges - one top and bottom on each side of
the fireplace front (see Figure 11). Use 8d nails
or their equivalent.

Use Top Flange For
1/2” Thick Drywall

Front Of
Fireplace

Use Center Flange
For Flush Mount

NOTE: DIAGRAMS & ILLUSTRATIONS ARE NOT TO SCALE.

9

LENNOX HEARTH PRODUCTS • MONTEBELLO® DV GAS FIREPLACES (LSM40/45MN-2, LSM40/45MP-2, LSM40/45EN-2) • INSTALLATION INSTRUCTIONS

E

A

B

D

Top View

Front View

5-3/32 (129)

Right Side View

14-1/8
8-1/2”
(216)

5-1/4”
(133)

(359)

26-15/32

(672)

C

25-29/32

(658)

25-1/2

(648)

7

2-1/2 (64)

(178)

19-5/8

(498)

Gas Inlet

(This

Side

Only)

Electrical

Inlet

8-3/8

(213)

F

G

H

J

A

B

C

8-1/2
(216)

13

(

330

)

VENT FRAMING

-

TOP VENT WITH 2 FEET
VERTICAL VENT AND
ONE 90° ELBOW

Framing should be constructed

of 2x4 or larger lumber.

Inches (mm)

(641)

25-1/4

15

(

381

)

6-1/2
(165)

1/2 A

FIREPLACE AND FRAMING SPECIFICATIONS

Framing Dimensions

Models A B C

LSM40-2

LSM45-2

Models P4 P4

LSM40M 35% 38.1

LSM40E 35.8

LSM45M 50.8 42.3

LSM45E 51.2

in. 50-3/4 43 75-1/8

mm 1289 1092 1908

in. 56-7/8 48 80-1/16

mm 1445 1219 2034

Efficiencies %

Natural Gas Propane

Figure 12

Model

No.

LSM40-2

LSM45-2

Notes

Diagrams, illustrations and photo­graphs are not to scale – consult
installation in structions. Product
design s, materials, dimensions,
specifications, colors and prices are
subject to change or discontinuance
without notice.

Vent Size

Co-axial DV

Vent Size

A B C D E F G H J

in. 50-5/8 37-1/4 42-7/8 25-5/16 34 37-5/8 33-3/32 29-9/32 34-3/4

mm 1286 946 1089 643 864 956 840 744 883

in. 56-11/16 42-1/4 47-7/8 28-3/8 40-1/8 43-5/8 38-3/32 34-1/2 40-59/64

mm 1440 1073 1216 721 1019 1108 968 876 1039

Fireplace Dimensions

8" Inner

11" Outer

10

NOTE: DIAGRAMS & ILLUSTRATIONS ARE NOT TO SCALE.

LENNOX HEARTH PRODUCTS • MONTEBELLO® DV GAS FIREPLACES (LSM40/45MN-2, LSM40/45MP-2, LSM40/45EN-2) • INSTALLATION INSTRUCTIONS

C

Back wall of chase/enclosure

(including any finishing materials)

D

A

B

Right Side
Front Corner
Of Fireplace
Framing

6-1/4”

(159 mm)

19-5/8”

(498 mm)

Model

No.

LSM40-2

LSM45-2

Figure 13 - Corner Framing with Square Termination (SV8HTS)

Step 2. ROUTING GAS LINE

Route a 1/2" (13 mm) gas line along the inside
of the right side framing as shown in Figure

14. Gas lines must be routed, constructed and
made of materials that are in strict accordance
with local codes and regulations.
All appliances are factory-equipped with a
flexible gas line connector and 1/2 inch shutoff
valve. (See Step 6 on Page 22).

The incoming gas line should be piped into the
valve compartment and connected in one of the
two methods as shown in Figure 37 on Page 22.

Figure 14

Proper Sizing of Gas Line

Properly size and route the gas supply line
from the supply regulator to the area where the
appliance is to be installed per requirements
outlined in the National Fuel Gas Code, NFPA

54 - latest edition (USA) or CAN/CSA-B149.1

- latest edition (Canada).

A B C D

in. 50-5/8 83-5/8 59-1/8 41-7/8

mm 1286 2124 1502 1064

in. 56-3/4 89-7/8 63-1/2 44-7/8

mm 1441 2283 1613 1140

Never use galvanized or plastic pipe. Refer
to Table 6 for proper sizing of the gas sup­ply line, if black iron pipe is being used. Gas
lines must be routed, constructed and made
of materials that are in strict accordance with
local codes and regulations. We recommend
that a qualified individual such as a plumber or
gas fitter be hired to correctly size and route
the gas supply line to the appliance. Installing
a gas supply line from the fuel supply to the
appliance involves numerous considerations of
materials, protection, sizing, locations, controls,
pressure, sediment, and more. Certainly no one
unfamiliar and unqualified should attempt sizing
or installing gas piping.

Inside Diameter (Inches)

Schedule 40 Pipe

Length (feet)

0-10 1/2 3/8

10-40 1/2 1/2

40-100 1/2 1/2
100-150 3/4 1/2
150-200 3/4 1/2

Table 6

NOTE: DIAGRAMS & ILLUSTRATIONS ARE NOT TO SCALE.

Schedule 40

Black Iron Pipe

Natural

Gas

Propane

Gas

Notes:

• All appliances are factory-equipped with

a flexible gas line connector and 1/2 inch
shutoff valve (see Figure 37 on Page 22).

• See Massachusetts Requirements on Page
4 for additional requirements for installations

in the state of Massachusetts in the USA.

• The gas supply line should Not be connected

to the appliance until Step 6 (Page 22).

• A pipe joint compound rated for gas should be
used on the threaded joints. Ensure propane

resistant compounds are used in propane
applications. Be very careful that the pipe

compound does not get inside the pipe.

• It is recommended to install a sediment trap

in the supply line as close as possible to the
appliance (see Figure 37). Appliances using
propane should have a sediment trap at the
base of the tank.

• Check with local building ofcial for local

code requirements (i.e. are below grade
penetrations of the gas line allowed?, etc.).

IMPORTANT: If propane is used, be aware that
if tank size is too small (i.e. under 100-lbs, if
this is the only gas appliance in the dwelling.
Ref. NPFA 58), there may be loss of pressure,
resulting in insufficient fuel delivery (which
can result in sooting, severe delayed ignition
or other malfunctions). Any damage resulting
from an improper installation, such as this,
is not covered under the limited warranty.

11