Heatilator LM42 User manual

Heatilator • LM42 • Installers Manual • 4087-901 • Rev A • 04/14/16 1
WOODBURNING FIREPLACE
Model(s):
Installation Manual
Installation and Fireplace Setup
WARNING
HOT SURFACES!
Glass and other surfaces are hot during
operation AND cool down.
Hot glass will cause burns.
• DO NOT touch glass until it is cooled
• NEVER allow children to touch glass
• Keep children away
• CAREFULLY SUPERVISE children in same room as
replace.
• Alert children and adults to hazards of high temperatures.
High temperatures may ignite clothing or other ammable
materials.
• Keep clothing, furniture, draperies and other ammable
materials away.
INSTALLER: Leave this manual with party responsible for installation and operation.
OWNER: Retain this manual for future reference.
LM42
LM42-SS
NOTICE: DO NOT discard this manual!
• Read all the instructions before starting
the installation. Follow these instructions
carefully during the installation to ensure
maximumsafetyandbenet.
• Comply with all minimum clearances to com-
bustiblesasspecied.Failuretocomplymay
causehousere.
Installation and service of this
appliance should be performed by
qualiedpersonnel.Hearth&Home
Technologies recommends HHT
Factory Trained or NFI certified
professionals.
Contact your dealer with questions on installation, operation, or service.
WARNING! Risk of Fire and/or Asphyxiation!

Heatilator • LM42 • Installers Manual • 4087-901 • Rev A • 04/14/16
2
Safety Alert Key:
• DANGER! Indicates a hazardous situation which, if not avoided will result in death or serious injury.
• WARNING! Indicates a hazardous situation which, if not avoided could result in death or serious injury.
• CAUTION! Indicates a hazardous situation which, if not avoided, could result in minor or moderate injury.
• NOTICE:Indicatespracticeswhichmaycausedamagetothereplaceortoproperty.
Table of Contents
1 Product Specic & Important Safety Information
A.FireplaceCertication 4
B.GlassSpecition 4
C.Non-CombustibleMaterials 4
D.CombustibleMaterials 4
2 Getting Started
A. Typical Fireplace System 5
B. Design and Installation Considerations 6
1.LocatingFireplace&Chimney 6
2. Selecting Fireplace Locations 7
3.SelectingFireplaceLocationOutdoors&
Requirements 8
C. Tools and Supplies Needed 10
D. Inspect Fireplace and Components 10
E. Fireplace System Requirements 11
3 Framing and Clearances
A. Fireplace Dimensions 12
B. Clearances 13
C. Construct the Chase 15
D. Frame the Fireplace 16
E. Secure and Level the Fireplace 16
F. ProtectiveMetalHearthStrips 17
G. Outside Air Kit (required) 18
H.Non-CombustibleFacingMaterialInstallation 19
4 Chimney and Termination Requirements
A. Chimney Requirements 20
B. Offsets/Returns 21
C. Termination Requirements 22
5 Chimney Installation
A. Typical Chimney System 23
B.AssembleChimneySections 24
C.SecureOffset/Return 24
D. Install Firestops 25
E. Install Attic Insulation Shield 26
F. ThimbleInstallation-ManufacturedHome 27
G. Roof Penetration 28
H.InstallChase/ChaseTop 28
I. InstallTerminationCap 29
6 Shrouds
A. Radiation Shield 31
B. Field Constructed Shrouds 31
1. Open Top Shroud 31
2.MailboxStyleShroud 32
3. Roofed Style Shroud 32
7 Facing, Mantels & Hearth Extensions
A.FinishingMaterial 33
B.HearthExtension,BuildingandFinishing 34
1. Fireplace Installed Flush on the Floor
 andHearthExtensionRaisedtoBottom
 ofFireboxOpening 35
2.RaisedHearthExtensionandRaisedFireplace 35
3.FireplaceOpeningandHearthExtensionFlush
with the Floor 35
C.MantelandWallProjections 36
D. Sidewalls/Surrounds 37
8 Fireplace Accessories
A. Gas Log/Lighter Provision 38
9 Reference Materials
A.ChimneyComponents 39
B.OptionalComponents 43
= Contains updated information.

Heatilator • LM42 • Installers Manual • 4087-901 • Rev A • 04/14/16 3
Customer:
Lot/Address
Model (circle one): LM42
YES IF NO, WHY?
Door and screen weights installed. Section Section 2
Required factory included non-combustible board is in place
Comments communicated to party responsible
4087-982 •Rev A •11/15
__________________________ by ______________________on _________
Protective hearth strips installed per manual requirements. Section 3
Outside air kit installed. Section 3
Hearth extension installed per manual requirements.
Verified all clearances meet installation manual requirements.
Mantels and wall projections comply with installation manual requirements.
Chimney Section 4 & 5
Attic insulation shield installed.
Shrouds Section 6
Shroud is installed properly per instructions.
Fireplace Setup Section 8
Hearth & Home Technologies recommends the following:
Facing, Mantels & Hearth Extensions Section 7
(Builder/Gen. Contractor) (Installer) (Date)
Comments:
Further description of the issues, who is responsible (Installer/Builder/Other Trades, etc.) and corrective action needed:
WARNING! Risk of Fire or Explosion! Failure to install fireplace acording to these instructions can lead to a fire or
explosion.
Manual bag and all of its contents are removed from the fireplace and given tothe party
responsible for use and operation.
Verified that the chase is insulated and sealed. Section 3
Verified clearances tocombustibles. Section 3
Fireplace is leveled and secured. Section 3
Hearth extension size/height decided. Section 7
Chimneyconfiguration complies with diagrams.
Chimney installed, locked and secured in place with proper clearance.
Chimney air kit installed.
Firestops installed.
•That this checklist remain visible at all times on the replace until the installation is complete.
ATTENTION INSTALLER:
Follow this Standard Work Checklist
This standard work checklist is to be used by the installer in conjuction with, not instead of, the instructions contained in this installation
manual.
Date Installed:
Location of Fireplace:
Installer:
Dealer/Distributor Phone #
Serial #:
Roof flashing installed.
Termination installed.
•Photographing the installation and copying this checklist for your le.
Combustible materials not installed in non-combustible areas.
All packaging and protective materials removed.
Refractory installed correctly.
Grate is properly installed.
Fireplace Install
LM42-SS

Heatilator • LM42 • Installers Manual • 4087-901 • Rev A • 04/14/16
4
C. Non-Combustible Materials
• Materialswhichwillnotigniteandburn,composedof
anycombinationofthefollowing:
- Steel - Iron
- Brick - Tile
- Concrete - Slate
- Glass - Plasters
• MaterialsreportedaspassingASTM E 136, Standard
Test Method for Behavior of Metals, in a Vertical
Tube Furnace at 750° C
D. Combustible Materials
• Materialsmadeoforsurfacedwithanyofthefollowing
materials:
- Wood - Compressedpaper
- Plantbers - Plastic
- Plywood/OSB - Sheet rock (drywall)
- Foaminsulation&sealants
• Anymaterialthatcanigniteandburn;ameproofedor
not, plastered or un-plastered
1 Product Specic & Important Safety Information
Section 1
B. Glass Specications
• This appliance is equipped with 5mm ceramic glass.
Please contact your dealer for replacement glass.
Not intended for use as a primary heat source.
This replace is tested and approved as a decorative
replace. It should not be factored as a primary heat
source in residential heating calculations.
Improper installation, adjustment, alteration, service
or maintenance can cause injury or property damage.
Refer to the owner’s information manual provided with
thisreplace.Forassistanceoradditionalinformation
consult a qualied installer, service agency or your
dealer.
WARNING
Fire Risk
WARNING
TOAVOIDTHERISKOFDAMAGINGFIREPLACEMA-
TERIALSANDINCREASINGTHERISKOFSPREAD-
ING A FIRE, DO NOT USE THE FIREPLACE TO
COOK OR WARM FOOD.
WARNING! THIS FIREPLACE MAY BE INSTALLED IN
MANUFACTURED HOMES, EXCEPT IN SLEEPING
ROOMS.
If installed with a gas log set, provisions for the National
FuelGasCodemustbemet.
Thisreplacecomplieswiththeinstallationrequirements
forHUD.
CAUTION! THE STRUCTURAL INTEGRITY OF THE
MANUFACTURED HOME FLOOR, WALL, AND CELING/
ROOF MUST BE MAINTAINED.
HeatilatorisaregisteredtrademarkofHearth&Home
Technologies.
WARNING! Risk of Fire! Hearth & Home Technologies
disclaims any responsibility for, and the warranty and
agency listing will be voided by the following actions.
DO NOT:
• installoroperatedamagedreplace
• modifyreplace
• install other than as instructed by Hearth & Home
Technologies
• operate the fireplace without fully assembling all
components
• overre
• install unvented gas log set
• install any component not approved by Hearth & Home
Technologies
• install parts or components not Listed or approved
Improper installation, adjustment, alteration, service or
maintenance can cause injury or property damage. For
assistance or additional information, consult a qualied
installer, service agency or your dealer.
A. Fireplace Certication
Thisreplacesystemhasbeentestedandlistedinaccor-
dancewithUL127andULC-S610standardsbyUnderwrit-
ers Laboratories Inc. for installation and operation in the
United States and Canada.

Heatilator • LM42 • Installers Manual • 4087-901 • Rev A • 04/14/16 5
2 Getting Started
A. Typical Fireplace System
Figure 2.1 Typical Fireplace System
Section 2
Termination Cap
Additional lateral
support for chimney
above roof (or enclosed
in chase) if needed
Chimney penetrates roof
preferably without affecting
roof rafters
Storm Collar Non-combustible
roof flashing maintains
minimum clearance
around chimney
Offset/Return
(with hanger straps) Support straps
on rafter supports
chimney (not shown)
Attic insulation shield
must be used to keep
insulation away
from chimney if
attic is insulated
Ceiling firestop
on floor of attic
Framing headed
off in ceiling joists Outside
combustion air
Mantel
Chimney system Enclosed space above
and around fireplace
Combustible
framing/header
on top of V-shaped
standoffs (spacers)
Chimney Air Kit (CAK-4A) (not
shown) must be used with SL300
chimney in Canada.
Non-combustible material
Outside
combustion air
Hearth Extension
Locate cooling air in the enclosure of
outdoor unit no less than 12 inches
off ground level.

Heatilator • LM42 • Installers Manual • 4087-901 • Rev A • 04/14/16
6
1. Locating Fireplace & Chimney
Locationofthereplaceandchimneywillaffectperfor-
mance.
• Installwithinthewarmairspaceenclosedbythebuilding
envelope. This helps to produce more draft, especially
duringlightinganddie-downofthere.
• Installingthereplaceinabasementisnotrecommended
due to negative pressure concerns.
• Penetrate the highest part of the roof. This minimizes
the effects of wind loading.
• Locate termination cap away from trees, adjacent
structures,unevenrooflinesandotherobstructions.
• Minimizetheuseofchimneyoffsets.
• Considerthereplacelocationrelativetooorandceiling
and attic joists.
• Take into consideration the termination requirements in
Marginal Location:
• Below peak
Location NOT recommended:
• Not the highest point of the roof
• Wind loading possible
Multi-level Roofs
Windward
Leeward
Recommended Location:
• Above peak
Recommended:
• Insulated exterior chase
in cooler climates
Recommended Location:
• Above peak
• Inside heated space
Location NOT recommended:
• Too close to tree
• Below adjacent structure
• Lower roof line
• Avoid outside wall
Marginal Location:
• Wind loading possible
Not recommended in basement due
to high negative pressure concerns
that effect draft
Figure 2.2 Recommended Chimney Locations
Sections4and5.
• Install the outside air kit with the intake facing prevailing
winds during the heating season.
• Ensure adequate outdoor air for all combustion
appliances and exhaust equipment.
• Ensure furnace and air conditioning return vents are not
locatedintheimmediatevicinityofthereplace.
• Avoidinstallingthereplaceneardoors,walkwaysor
small isolated spaces.
• Recessedlightingshouldbea“sealedcan”design.
• Attic hatches weather stripped or sealed.
• Attic mounted duct work and air handler joints and seams
taped or sealed.
B. Design and Installation Considerations
Consideration should be given to these factors before
deciding on a location.
NOTICE: Check building codes prior to installation.
• InstallationMUSTcomplywithlocal,regional,stateand
national codes and regulations.
• Consultlocalbuildinginspector,reofcialsorauthorities
having jurisdiction over restrictions, installation inspection
and permits.
• Before installing,determinethefollowing:
- Wherethereplaceistobeinstalled.
- Thechimneysystemcongurationtobeused.
- Facing, mantel, hearth construction and nishing
details.
- Gas supply piping.

Heatilator • LM42 • Installers Manual • 4087-901 • Rev A • 04/14/16 7
Note: Measurements are FRAMING dimensions only. Adjust
framing dimensions for interior sheathing (such as sheet rock).
*8 in. (203 mm) extra space
included for outside air
connection. If outside air duct
has no bend, this dimension
may be reduced as long as
minimum clearances are met.
20 (508)
12 (305)
20
(508)
Note: Unit standoffs can be placed against combustible materials. Maintain 1-1/2 in.
(38mm) air space otherwise. Do not fill area with insulation. Do not remove standoffs.
Across a
corner
In an exterior chase
Along a wall
As a room
divider
*
*
*
*
**
*
*
Figure 2.3 Fireplace Locations
NOTICE:
• Illustrationsandphotosreecttypicalinstallationsand
are FOR DESIGN PURPOSES ONLY.
• Illustrations/diagrams are not drawn to scale.
• Actual installation/appearance may vary due to individual
design preference.
• Hearth & Home Technologies reserves the right to alter
its products.
WARNING! In addition to these framing dimensions, also
reference the following section: Clearances (Section 3).
2. Selecting Fireplace Locations Within A Room
Thisreplacemaybeusedasaroomdivider,installed
along a wall, across a corner or used in an exterior chase.
See Figure 2.3.
WARNING! Risk of Fire! Hearthextensiondesignmustbe
determinedbeforeframingandinstallationofreplace.Any
installation outside the scope as stated in this manual please
contactyourauthorizedHHTdealerpriortoinstallation.

Heatilator • LM42 • Installers Manual • 4087-901 • Rev A • 04/14/16
8
3. Selecting Fireplace Location Outdoors
The LM42-SS (Stainless) replace may be installed out-
doors.Thisreplacewillshedmoderateamountsofwater,
butisnotwaterproof.Waterandcondensingwatervapor
may enter the chase under certain conditions.
The replace will not perform as an exterior wall. Mois-
turepenetrationmustbeconsideredforconstructionthat
placesthereplaceagainststructurewallsoronmoisture
sensitive surfaces.
• Exterior Walls (see Figure 2.4)
 Hearth & Home Technologies recommends that the
replacechasebeconstructedoutsidethestructure’s
weatherenvelope.Wheretheplatformmeetsthewall,
useaashingdetailsimilartothatrequiredforattached
decks. Chase platforms, including hearths, should slope
away from the structure at 1/8 in to 1/4 in. per foot.
Thereplacecanbeshimmedlevel.Buildtheoutside
enclosure out of standard building materials, being
carefultomaintaintheminimumairclearancesspecied
in these installation instructions.
• Freestanding Installations (see Figure 2.5)
 Wheninstallingthisreplaceasafreestandingreplace
onyourporch,patioorinyouryard,itmustbeenclosed
topreventimpactdamagetothereplace.Theexterior
oftheenclosuremaybenishedinatexturedplywood,
awoodclapboardsiding,brick,oraculturedstone.Vinyl
siding is not recommended for use on the front of the
replaceduetotheheatthereplaceproduces.This
can cause the vinyl siding to deteriorate.
• Cooling Air
WARNING! Cooling air must be provided when install-
ing in freestanding combustible enclosure or on combus-
tible surface.
• Locatecoolingairinlettopreventblockagefromleaves,
snow/ice,orotherdebris.Blockagescouldcausethe
unit to overheat.
• Coolingaircanbeprovidedby cutting a 6 in.holein
the enclosure and attachng an outside air inlet hood,
Part#4059-051orcoveringitwithscreen.*Noducitng
is required.
Fire Risk
Provide adequate clearances.
• Around air openings
• Tocombustibles
• For service access.
Locatereplaceawayfromtrafcareas.
WARNING Note:
• Illustrationsandphotosreecttypicalinstallations
and are FOR DESIGN PURPOSES ONLY.
•Illustrations/diagrams are not drawn to scale.
•Actual installation/appearance may vary due to
individual design preference.
• Hearth&HomeTechnologies reservestherightto
alter its products.
• Outside Air Kit
The Outside Air Kit is required for the performance of
thereplaceeventhoughitisinstalledoutdoors.The
Outside Air Kit is installed on the right hand side of the
replace.
• Cut a 6-1/2 in. (165mm) hole in outside wall to
accomodate air piping.
• Use 6 in. (152mm) ex (not supplied) to directly
connectoutsideairtoreplaceintake.
• Use the supplied outside air inlet hood. Itcanbe
painted to match/accent the color of the structure.
• When Installed on Surfaces Where Water May Collect
or Cause Damage:
 Hearth & Home Technologies recommends that a
drainage pan be placed under the unit. This can be
constructedofmetal,adhesivepolymermembrane(such
asiceandwatershield)orothersuitablematerials.A
meansofdrainageoutofthepansuchastubesorweep
holesshouldbeprovided.Aslopeof1/8in.to1/4in.per
foottowardsthedrainportissuggested.Thereplace
canbeshimmedlevel.
 Hearthsshouldslopeawayfromthefrontofthereplace
andchaseat1/8in.to1/4in.perfoot.Sparkstripsmust
beusedontopofanycombustiblehearthmaterialsused
for moisture management.

Heatilator • LM42 • Installers Manual • 4087-901 • Rev A • 04/14/16 9
Figure 2.4 Fireplace Locations Outdoors (LM42-SS only)
(Combustible Structure)
(Enclosed Fireplace)
10 ft
Min.
(8ft. 8in. minimum height
from base of unit)
FREESTANDING
INSTALLATION
COOLING AIR
REQUIRED
Figure 2.5 Freestanding Fireplace Locations Outdoors (LM42-SS only)
Note: If this surface is
inside the building’s
warm air envelope... ...then this surface
must be an exterior
wall system.
20 (508)
*8 in. (203 mm) extra space
included for outside air
connection. If outside air duct
has no bend, this dimension
may be reduced as long as
minimum clearances are met.
*
*
*
*
*
*20 (508)

Heatilator • LM42 • Installers Manual • 4087-901 • Rev A • 04/14/16
10
C. Tools and Supplies Needed
Beforebeginningtheinstallationbesurethefollowing
toolsandbuildingsuppliesareavailable:
Reciprocating saw Framing material
Pliers Non-combustiblesealant
Hammer Gloves
Phillips screwdriver Framing square
Flatbladescrewdriver Electricdrillandbits
Plumbline Safetyglasses
Level Tape measure
1/2-3/4in.length,#6or#8self-drillingscrews
Misc.screwsandnails
600° Silicone sealant 300° Silicone sealant
D. Inspect Fireplace and Components
WARNING! Risk of Fire and Asphyxiation! Damaged
parts could impair safe operation. DO NOT install dam-
aged, incomplete or substitute components.
CAUTION! Risk of Cuts/Abrasions. Wear protective
gloves and safety glasses during installation. Sheet metal
edges are sharp.
1. Unpacking
a. Remove the carton
 b. Removecornerposts
 c. Removethenon-combustiblekitfromtherearof
  thereplace
i. Set aside for future installation
 d. Removetheweightassembliesfromtheholders
on the front of the pallet
e. Remove the weight holders from the pallet
f. Pivot carry handle forward to allow access to side
cover panel
g. Remove the side cover access panel from side of
unit
i. Remove 10 screws from each side. Retain
screws.
  ii.Laythenailingangesaside.SeeFigure2.6.
Figure 2.6
Non-combustible
Kit
Remove Screws
Remove Screws
Side Cover Access
Carry Handle
Nailing Flange
Weight Holder
Weight Assemblies
Weight Holder
Weight Assemblies

Heatilator • LM42 • Installers Manual • 4087-901 • Rev A • 04/14/16 11
• NOTE: Remove fireplace and components from
packaging and inspect for damage.
• Chimney system components and other optional
components are shipped separately.
• Report to your dealer any parts damaged in shipment.
E. Fireplace System Requirements
TheHeatilatorreplacesystemrequirementsconsistof
thefollowing:
• Fireplace
- Refractory(includedwithreplace)
- Firescreen(includedwithreplace)
- Grate(includedwithreplace)
- Door(includedwithreplace)
- HearthExtension(required,notincluded)
See Section 7 for construction requirement
• Outside Air System (required)
- Inlethoodandcollarincludedwithreplace
- Flex (required, not included)
- Cooling air required for outdoor freestanding unit only
ifusingcombustiblematerial(hoodnotincluded)
• Chimney System (components as required)
- AtticInsulationShield(includedwithreplace)
r. Repeat for the other side. See Figure 2.8.
 h. Disconnectthecabletowardstherearoftheunit
  (GlassDoor)andinstalllargerweightassembly
(28 weights)
 i. Disconnectthecabletowardsthefrontoftheunit
(Screen Door) and install the smaller weight
  assembly(8weights).Doublecheckbothsides
to make sure the snap rings are all straight up.
j. Reinstall the side cover access panel
  i.Nailingangesshouldgoonoppositeasthe 
direction taken off
  ii.Whennailingangesarebentout,they 
  shouldbeushwithfrontofunit.
k. Repeat for the other side. See Figure 2.7.
 l. Removethedustcoverfromreplaceopening 
and set aside
 m. Removethecomponentsfromtherebox
i. Attic Insulation Shield
  ii. OAHoodandcollar
  iii. Manualbag
  iv. Removabledoorhandle
v. Protector Strips
n. Locate the (4) screws (2 on each end) that hold the
doorandscreentotheshippingbracketandremoveand
discardthem.*(seegure2.8)
o. Loosen two screws towards bottom of the shipping
bracketonbothsides(donotremovecompletely)
p. Removescrew at thecenter of theshipping bracket,
removebracketandreinstallcenterscrewaftershipping
brackethasbeenremoved
q. Tightenscrewsatthebottomthatwereloosenedear-
lier
Figure 2.7
s. Checkdooroperationbeforesettingunit
t. Removescrewsfrompalletbrackets
*Shippingbracketcanremaininplaceuntilunitissetbut
weightsshouldbeinstalled.
Figure 2.8
Remove screw at bottom of
glass door and screen door.
Remove screw.
Shipping Bracket
Loosen screws (both
sides). DO NOT remove.
Screen Weight Door Weight

Heatilator • LM42 • Installers Manual • 4087-901 • Rev A • 04/14/16
12
3 Framing and Clearances
Figure 3.1 Fireplace Dimensions
A. Appliance Diagrams
Dimensions are actual appliance dimensions. Use for reference only. For framing dimensions and clearances refer to Figure 3.2
&3.3.
Section 3

Heatilator • LM42 • Installers Manual • 4087-901 • Rev A • 04/14/16 13
B. Clearances Within Enclosed Area
WARNING! Risk of Fire!
You must comply with all minimum air space clearances
tocombustiblesasspeciedinFigure3.2.WARNING! DO
NOT PACK REQUIRED AIR SPACES WITH INSULATION
OR OTHER MATERIALS. Framing or nishing material
usedonthefrontof,orinfrontof,thereplacecloserthan
the minimums listed must be constructed entirely of non-
combustible materials (i.e., steel studs, concrete board,
etc.).Failuretocomplymaycauseare.
Figure 3.2 Clearances to Combustible Materials
Minimum Clearances to Combustibles
WITHIN ENCLOSURE AREA
Standoffstobackwall 0 in. (0 mm)
Standoffs to sidewall 0 in. (0 mm)
Top standoffs to header 0 in. (0 mm)
Door opening to sidewall 12 in. (305 mm)
(insulation)
0 in. to level
of standoffs
Attic
Insulation
Shield
(ceiling)
(roof)
(attic)
(ceiling)
Ceiling Firestop
Offset/Return (secured
with hanger straps)
Storm Collar
Roof Flashing
Must have 2 in. (51 mm)
minimum clearance
to header
0 in.
to floor
2 in. (51 mm) min.
Shaded areas
represent
2 in. (51 mm) min.
air space clearance
required around pipe
Combustible Object
48 in.
1219 mm

Heatilator • LM42 • Installers Manual • 4087-901 • Rev A • 04/14/16
14
B
D
A
C
APPLIANCE MAY BE INSTALLED
OFF OF FLOOR***
NOTE: Must have
double 2 x 4 on each
side of opening.
G
E
F
E=MEASUREMENT FROM TOP OF
FIREPLACE OPENING
TO CEILING
H
I
MINIMUM FRAMING DIMENSIONS*
LM42
A B C* D E F G H I
Rough
Opening
(Vent Pipe)
Rough
Opening
(Height)
Rough
Opening
(Depth)
Rough
Opening
(Width)
Clearance
to Ceiling
Combustible
Floor
Minimum
Hearth
Depth
Standoff
Behind
Appliance
Standoff
Side of
Appliance
Inches 14-1/2 60-1/4 24 65-1/2 36 0 16 0 0
Millimeters 368 1530 610 1664 914 0406 0 0
* = Adjust framing dimensions for interior sheathing (such as sheetrock)
***= If appliance is installed off of oor, maintain required clearances to combustibles.
Construct platform in accordance with local building codes.
Figure 3.3 Clearances to Combustibles

Heatilator • LM42 • Installers Manual • 4087-901 • Rev A • 04/14/16 15
C. Construct the Chase
Achaseisaverticalboxlikestructurebuilttoenclosethe
replace and/or its vent system. Vertical chimneys that
runontheoutsideofabuildingmustbeinstalledinsidea
chase.SeeFigure3.4.
Constructionofthechasemayvarywiththetypeofbuild-
ing.LocalbuildingcodesMUSTbefollowed.
Hearth&HomeTechnologiesrecommends:
- The inside surfaces be drywalled and taped (or
the use of an equivalent method) for maximum air
tightness to the false ceiling.
- In cold climates, the walls of the chase should be
insulated to the level of the false ceiling as shown in
Figure3.4.Thiswillhelpreduceheatlossfromthe
homearoundthereplace.
- Holes and other openings should be caulked with
hightemperaturecaulkorstuffedwithunfacedber
glass insulation.
Ceiling
Firestop
Metal Chase To p
Round Termination Cap
False Ceiling
Insulation in the
outside walls
of the chase
Attic
Insulation
Shield
Chimney
Ceiling
Firestop
Tabs
False Ceiling
False Ceiling
Insulation
Insulation
Storm Collar
Figure 3.4 Chase Assembly
1 2 3
All outside walls should be insulated.
Figure 3.5 Chase Applications
1. Fireplace and chimney enclosed in an exterior chase.
2. Chimney offset through exterior wall and enclosed in chase.
3. Chase constructed on roof.
• Requirementsforconstructingthechase:
- Arestopspacerandatticinsulationshieldshould
beinstalledatthefalseceiling.SeeFigure3.4.
- Thechasemustbeproperlyblockedtopreventblown
insulationorothercombustiblesfromenteringand
makingcontactwithreplaceorchimney.
- The chase top must be constructed of non-
combustiblematerial.
Three examples of chase applications are shown in Fig-
ure 3.5.
WARNING! Risk of Fire! DO NOT sealareabetweenre
stop opening and chimney pipe except where they enter
the attic or leave the warm air envelope of the home (use
600° F sealant).
WARNING! Risk of Fire! Youmustmaintainaminimum2
in. (51 mm) air space clearance to insulation and framing
surrounding the chimney system.

Heatilator • LM42 • Installers Manual • 4087-901 • Rev A • 04/14/16
16
D. Frame the Fireplace
WARNING! Risk of Fire! Hearthextensiondesignmustbe
determinedbeforeframingandinstallationofreplace.Any
installation outside the scope as stated in this manual please
contactyourauthorizedHHTdealerpriortoinstallation.
Thereplacewilltaframedopeningof:
LM42/LM42-SS: 60-1/4 in. (1530 mm) tall and 65-1/2 in.
(1664mm)wide.
Figure3.6showsatypicalframing(using2x4lumber)of
the replace, assuming combustible materials are used.
WARNING! Risk of Fire! Comply with all minimum clear-
ancesspecied.
• Standoffs can be 0 in. to combustibles.
• Chimneysectionsatanylevelrequirea2in.(51mm)
minimum air space clearance between the framing and
chimney section.
• DO NOT pack required air space with insulation or other
materials.
All required clearances to combustibles around the re-
place must be adhered to. See Figure 3.3.Any framing
acrossthetopofthereplacemustbeabovethelevelof
the top standoffs.
The nished cavity depth must be no less than 24 in.
(610mm)fromthenishedbackwalltotheoutsideoffront
wall framing.
CAUTION! Risk of Cuts/Abrasions. Wear protective gloves
and safety glasses during installation. Sheet metal edges
are sharp.
• DO NOT install against vapor barriers or exposed
insulation.
• Ensure insulation and vapor barriers are secured in
placewithrespecttothereplaceandchimneysystem.
E. Secure and Level the Fireplace
Thisreplacemaybeplacedoneitheracombustibleor
noncombustiblecontinuousatsurface.DO NOT install
directlyoncarpeting,vinyl,tileoranycombustiblemate-
rial other than wood.
Thereplaceshouldbepositionedsothefaceofthenon-
combustiblematerialonthereplacewillbeushwiththe
face of the drywall on the walls.
Levelthereplaceandshimasnecessary.Squarethe
unitandfastenunitnailingangestoframingusingnails
orscrewsthroughthenailingtabs.
Someguresinmanualshowthereplaceinstalledonthe
oor.However,thisreplacecanbeelevatedofftheoor
providedthatthereplaceisproperlysupportedbyframing
materials and the ceiling clearances are maintained.
Figure 3.6 Nailing Tab Locations
NAILING TABS
BOTH SIDES

Heatilator • LM42 • Installers Manual • 4087-901 • Rev A • 04/14/16 17
F. Protective Metal Hearth Strips
Figure 3.7 Position the Protective Metal Hearth Strips
• Locate the two protective metal hearth strips measuring
approximately26in.x4in.(660mmx102mm)included
withthisreplace.
• Slide each metal strip 2 in. (51 mm) under front edge of
replace.
• Overlapstripsinthemiddleofreplaceopeningby1in.
(25 mm) minimum.
• Metalstripsmustextendbeyondthefrontandsidesof
thereplace opening byat least 2in. (51mm).  See
Figure 3.7.
• Whenthereplaceopeningiselevatedmorethan12in.
(305mm)abovethehearthextension,protectthejoint
of the hearth extension and wall with metal hearth strip.
Seal with grout, mortar or high temperature sealant.
• Refer to Section 7.
WARNING! Risk of re! High temperatures, sparks,
embers or other burning material falling from the
replacemayigniteooringorconcealedcombustible
surfaces.
• Protective metal hearth strips MUST be installed over
combustible surfaces.
• Hearth extensions MUST be installed exactly as
specied.
Protective metal strips are placed 2 in.
(51 mm) under the front of the
fireplace and must extend beyond the
front and sides of fireplace opening by
2 in. (51 mm).
1 in. (25 mm)
overlap
2 in. min.
(51mm)
2 in. min.
(51mm)

Heatilator • LM42 • Installers Manual • 4087-901 • Rev A • 04/14/16
18
G. Outside Air Kit
Wheninstallinganoutsideairkit,itisrecommendedtouti-
lize the shortest duct run to optimize the performance of
the outside air kit using up to a maximum length of 30 ft.
Theoutsideairinlethoodshouldbepositionedinaman-
nerthatwillnotallowsnow,leaves,etc.toblocktheinlet.
Insomeinstallationstheairductmayneedtoberunverti-
cally.Insuchaninstallation,a3ft(914mm)heightdiffer-
ence must be maintained from the top of the uppermost
chimney section to the outside air inlet hood.
RefertoFigures3.8and3.9whenplacingtheoutsideair
inlet hood.
The outside air kit is installed on the right hand side of the
replace.
• Cut a 6-1/2 in. (165 mm) hole in outside wall to
accommodate air piping.
• Use6in.(152mm)exorrigidducting(notsupplied)to
directlyconnectoutsideairtoreplaceintake.Insulate
the pipe to prevent frost condensation.
• Use the supplied outside air inlet hood.
• Seal between the wall and the pipe with silicone to
prevent moisture penetration and air leaks.
• Sealbetweentheoutsideairinlethoodandthehouse
withsiliconetopreventairinltration.
WARNING! Risk of Fire or Asphyxiation! DO NOT draw
outsidecombustionairfromwall,oororceilingcavity,or
enclosed spaces such as an attic or garage.
• DO NOT place outside air inlet hood close to exhaust
vents or chimneys. Fumes or odor could be drawn into
theroomthroughthereplace.
• Locate outside air inlet hood to prevent blockage from
leaves, snow/ice, or other debris. Blockages could cause
combustion air starvation.
Figure 3.8 Outside Air Inlet Locations
Outlet placed
higher than 3 ft
below the
termination cap
Attic space
Garage or
combustible
liquids storage
Outlet blocked by
snow, leaves, etc.
Clear area
outside
house or in
ventilated
crawl space
YES
NO
NO
NO
NO
Factory-built
fireplace
• Use UL181 Class 1 or Class 0 rigid or flexible ducting.
• Install with short run or mainly straight duct, except small
dip for cold air trap which will help prevent flow of cold air.
• Secure flex duct with screws or wire ties.
Figure 3.9 Outside Air Installation
3 ft min. from
top of uppermost
chimney section
to air inlet.

Heatilator • LM42 • Installers Manual • 4087-901 • Rev A • 04/14/16 19
WARNING! Risk of Fire!
• Follow these instructions exactly.
• Facing materials must be installed properly to prevent
re.
• No materials may be substituted without authorization
by Hearth & Home Technologies.
H. Non-Combustible Facing Material Installa-
tion
Makesurethereplacehasbeensecuredinplacetothe
wallstudswiththenailinganges.(Thereplacecanalso
beattachedtotheoorwithLbracketsthatattachedthe
replacetothepallet.)
• Slidethetopboarddownthefrontoftheunitandbehind
theangesaroundtheopeningofthereplace.
• Securetheboardtothereplaceatthepredrilledholes
withthe1-1/4”inchscrewsprovided.Attachtheboard
totheframingmemberswithregularsheetrockscrews
or nails.
• Slidethesideboardsinplacefromeachsidebehindthe
angesaroundtheopeningofthereplace.
• Securetheboardtothereplaceatthepredrilledholes
withthe1-1/4”inchscrewsprovided.Attachtheboard
totheframingmemberswithregularsheetrockscrews
or nails.
• Useawetorsoftbrushtoremovedustordirtfromfacing
material.
• Seesection7fornishingmaterialsguidelines.
Figure 3.10 Non-Combustible Facing Material

Heatilator • LM42 • Installers Manual • 4087-901 • Rev A • 04/14/16
20
6 ft (1.83 m) max.
unsupported chimney
above roof
20 ft (6.10 m) max.
pipe between an
offset & return
35 ft (10.7 m)
max. straight
unsupported
chimney height
14 ft (4.28 m) min. height/single offset-return
16.5 ft. (5.41 m) min. height/double offset-return
90 ft (27.4 m) max. height
56-5/8 in.
(1538 mm)
Effective
Height
Ceiling firestop
Figure 4.1 Chimney Requirements
NOTICE: A maximum of two pairs of offsets and returns
may be used. Offsets may be used directly off the top of
thereplace.
Minimum overall straight height 14 ft 4.28m
Minimum height with single offset/
return
14 ft 4.28m
Double offset/return minimum height 16-1/2
ft
5.41 m
Maximum height 90 ft 27.43m
Maximum chimney length between
an offset and return
20ft 6.1 m
Maximum distance between chimney
stabilizers
35 ft 10.67m
Maximum unsupported chimney
length between the offset and return
6 ft 1.83m
Maximum unsupported chimney
heightabovethereplace
35 ft 10.67m
Maximum unsupported chimney
above roof
6 ft 1.83m
FreestandingUnit(using(1)SL348) 8ft
8in.
2.64m
WARNING! Risk of Fire! Youmustmaintain2in.(51mm)
air space clearance to insulation and other combustible
materials around the chimney system.
NOTICE: You must provide support for the pipe during
construction and check to be sure inadvertent loading has
notdislodgedthechimneysectionfromthereplaceorat
any chimney joint.
A. Chimney Requirements
Verticaldistancesaremeasuredfromthebaseofthe
replaceasshowninFigure4.1.
• Minimum overall straight height is 8 ft 8 in. if the
replaceisfreestandingandaminimumof10ftfroma
combustiblestructure.SeeFigure3.2.
• Chimneymustextend2ft.(.6m)aboveanyportionof
the roof within 10 ft (3m) of the chimney. Refer to Figure
4.3.
4 Chimney and Termination Requirements
Table 4.2 Chimney Component Dimensions
Table 4.1 Chimney Requirements
Section 4
HEIGHT OF CHIMNEY COMPONENTS in. mm
Chimney Stabilizer
SL3 4-3/4 121
Offsets/Returns
SL315 13-3/8 340
SL330 15-1/2 394
Chimney Sections*
SL306 4-3/4 121
SL312 10-3/4 273
SL318 16-3/4 425
SL324 22-3/4 578
SL336 34-3/4 883
SL348 46-3/4 1187
* Dimensions reect effective height.