Montigo HW42DF Instruction manual

XG0191 Canadian Heating Products Inc. Langley, BC V4W 4A Montigo Del Ray Corp. Ferndale, WA 98248 031010
HW42DF
Installation Operation & Maintenance Manual
Check local codes and read all instructions prior to installation.
HW42DF Gas Fireplace
HW42DF Shown with Designer Logset
www.montigo.com
For Your Safety:
Do not store or use gasoline or other flammable vapors and liquids in the
vicinity of this or any other appliance.
Safety Notice:
Glass doors on gas fireplaces are extremely hot while the fireplace is on and remain
hot even after the fireplace has been turned off. Safety screens are available and
can reduce the risks of severe burns.
®
C US
Warning:
Improper installation,adjustment,alteration,serviceor maintenancecan cause
injury or property damage. Refer to this manual. For assistance or additional
information consult a qualied installer, service agency or the gas supplier.
Warning:
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 re department.
• Installer: Leave this manual
with the appliance.
• Consumer: Leave this
manual for future reference.

Page 2
HW42DF Gas Fireplace
Part No. XG0191 - 031010
Warning:
Read this manual before installing, operating or troubleshooting this
appliance. Please retain this owner's manual for future reference.
Congratulations
Congratulations on selecting a Montigo gas replace, an elagent
and well designed gas replace built to your specications. The
Montigo gas replace you have selected is designed to provide
the utmost in safety, reliability, and engineering standards.
As the owner of this new replace, you'll want to read and care-
fully follow all the instructions contained in this Installation,
Operations and Maintenance manual. Pay special attention to all
cautions, warnings, and Important warnings.
This owner's manual should be retained for future reference. We
suggest that you keep it with all your other important documents
and product manuals.
The information contained in this owner's manual, unless noted
otherwise, applies to all models, and gas control systems.
Your new Montigo gas replace will give you years of durable,
reliable use. Welcome to the Montigo family of gas replace
products.
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: Used to address practices not related to personal injury.
•Important: Used to address practices not related to personal injury.
Congratulations
Safety Alert Key
Introduction............................................................................... 3
Installation
Installing and Framing the Fireplace.............................. 4
Installing the Gasline...................................................... 5
Vent Installation.............................................................. 5
Installation Requirements .................................. 5
Installing the Remote Switch ............................. 5
Vent Terminations .............................................. 6
  InstallingtheNailingange................................ 6
Top Vent Runs.........................................................7 - 10
Side Vent Runs ..................................................... 10 - 11
 Finishingaroundthereplace
Fireplace Facing .............................................. 12
Mantels and Surrounds ................................... 13
Wiring ......................................................................... 12
Removing and Installing the Door................................ 13
Table Of Contents
Installing Logset ....................................................14 - 15
Operation .........................................................................16 - 19
Maintenance ....................................................................19 - 21
General......................................................................... 19
Cleaning....................................................................... 19
Troubleshooting ....................................................20 - 21
Spare Parts .................................................................. 21
Warranty ................................................................................. 22
Appendix
A. Termination Locations.............................................. 23
B State of Massachusetts / Amendment ..................... 24
Notes: ......................................................................... 25

Page 3
HW42DF Gas Fireplace
Part No. XG0191 - 031010
Introduction
CAUTION!
Duetoitshigh operatingtemperatures,theapplianceshould
belocated outoftraffic &away fromfurniture and draperies.
Children and adults should be alerted to the hazards
of the high surface temperature, which could cause
burns or clothing ignition.
Young children should be carefully supervised when
they are in the same room as the appliance.
Clothing or other flammable materials should not be
placed on or near the appliance.
WARNING!
When this appliance is installed directly on carpeting, tile or any
combustiblematerialotherthanwoodooring,itmustbeinstalled
on a metal or wood panel extending the full width and depth of
the appliance.
Thank You for choosing a Montigo Gas Fireplace.
About this Fireplace:
The HW42DF is an Premium replace with a Spectacular Designer
LogSet.ThisreplacescanbeconvertedtobothaTopVentorRear
Ventapplication,(seespecicsintheventingsectionofthisinstruction
Manual),andareavailableinthespecicmodelsbelow.
The HW42DF is rated for Natural Gas at 34,000 Max. BTU/H (9.96),
25,000BTU/H Kilowatts Input.
► HW42DF; Top or Rear Vent convertible, Millivolt Pilot
► HW42DF-I; Top or Rear Vent convertible, (HSI Ignition)
► HW42DF-F; Top or Rear Vent convertible, (IPI Electronic Ignition)
This manual covers installation, operation and maintenance. Lighting,
operation and care of this replace can be easily performed by the
homeowner. However, all installation and service work should be
performedbyaqualiedorlicensedinstaller,plumber,orgastterwho
isqualiedorlicensedbythestate,province,region,orgoverningbody
in which the appliance is being installed.
This manual covers all models and unless otherwise specied, the
designationHW42DFreferstoall variations of the modelabove.Sections
whicharespecictoaparticularvariationaremarkedwitha
symbol, plus the appropriate model number.
Warranty and Installation Information:
The Montigo warranty will be voided by, and Montigo disclaims any
responsibility for, the following actions:
►   Modication of the replace and/or components including Direct-Vent
assembly or glass doors.
►UseofanycomponentpartnotmanufacturedorapprovedbyMontigoin
combinationwiththisMontigoreplacesystem.
►Installationotherthanasinstructedinthismanual.
Consult your local Gas Inspection Branch on installation requirements
forfactory-builtgasreplaces.Installation&repairsshouldbedoneby
aqualiedcontractor.
Installations in Canada must conform to the current CAN/CGAB-149.1
and .2 Gas Installation Code and local regulations. If the optional air-
circulatingfankit isinstalled,itmustbeelectricallygroundedinaccordance
with CSA C22.1 Canadian Electrical Code Part 1 and/or Local Codes.
Installations in the USA must conform to local codes, or in the absence
of local codes to the National Fuel Gas Code, ANSI Z223.1-1988. If the
optional air-circulating fan is installed, it must be grounded in accordance
with local codes or, in the absence of local codes, with the National
Electrical Code, ANSI/NFPA 70-1987. See Appendix for installation
within the State of Massachusetts. Thisreplacemustcomplywith
NFPA-54 Chapter 10.

Page 4
HW42DF Gas Fireplace
Part No. XG0191 - 031010
46 1/2 45
9”
37
Header Header
Shelf
MELS hort
Shelf
50
Min
46 1/
17 1/2”
18” Max
90 elbow
46 1/2
Installation
Installing The Fireplace Shell
The HW42DFreplacemaybeinstalledinanylocationthatmaintains
proper clearances to air conditioning ducts, electrical wiring and plumb-
ing. Safety, as well as efciency of operation, must be considered
whenselectingthereplacelocation.Trytoselectalocationthatdoes
notinterferewithroomtrafc,hasadequateventilation,andoffersan
accessible pathway for Direct Vent installation. Refer to page 4 - Vent
Installation for more information.
Thereplacedimensionsareshownbelow:
When installing a shelf over the top of  the replace, the following
guidelines must be adhered to: For Rear Vent applications the
minimumclearancefromthetopofthereplacetoashelfis9".For
Top Vent applications, the minimum clearance is 17 1/2". (Minimum
2" clearance must still be maintained around the vent pipes.)
Figure 4. Framing for shelves over the replace.
Top Vent
Figure 3. Minimum Corner framing dimensions, using a 45° elbow.
Figure 2. Framing dimensions.
* When sheetrock is
not used behind the
fireplace, framing
depth may be reduced
by 5/8"
Framing
WARNING:
When this appliance is installed directly on carpeting, tile or
anycombustiblematerialotherthanwoodooring,itmustbe
installed on a metal or wood panel extending the full width and
depth of the appliance.
Rear Vent
* Clearance from top of the Fireplace to a combustible ceiling within the fireplace
enclosure.
** Refer to Pages, 10 & 11.
Top View
Front View Side View
Clearances
These clearances apply to all dimensions except the framed opening,
where the clearance to combustibles is 0". The HW42DF clearance to
unprotectedcombustiblewallswhichareperpendiculartothereplace
opening, must not project beyond the shaded area shown in Fig. 24.
For protection against freezing temperatures, it is recommended that
outer walls of the chase be insulated with a vapor barrier. This will reduce
thepossibilityofacold-airconvectioncurrentonthereplace.
The HWDF Series clearances to combustible materials are:
Figure 1. Fireplace dimensions.
G
H
JK
C
L
I
C
L
K
J
G
B
K
J
L
N.G. 5/8
N.G. 5/8
B
A
C
DD
D
F
6 1/4”
5 1/4”
2
21/8”
421 /4”
46 1/2”
67 1/2
0" clearance
to corners only
42 1/4
47 1/2”
Top - Rear Vent * 9"
Top - Top Vent 17 1/2”
Back 3"
Sides 1"
Floor 0"
Mantle** 4"
HW42DF
42 40 39 11
/
4283
/
433
1
/ 420
18
28
HW42DF 1
/
2
12 5
ACEGIK
BDFHJL
1
/
2

Page 5
HW42DF Gas Fireplace
Part No. XG0191 - 031010
Installation
Vent Installation
This section covers the installation of direct venting and terminations.
Installation Requirements
■ HW42DFreplacesis certiedforusewithMontigoPremiumSeries(5"/
8")ventingcomponents.
■ Minimumclearancetocombustibleconstructionaroundtheventpipeis1"
on all sides, except on horizontal venting where the top of the pipe must
haveaclearanceofatleast2".
■ UseonlycertiedMontigoventcomponents.(Useofotherpartswillvoid
theMontigowarranty,andmayimpedetheoperationofthereplace.)
■All joints must be secured with a minimum of two screws per joint
■Vent terminations must not be recessed in walls or siding
■Horizontal runs must be supported by a minimum of two supports per hori-
zontal run. A minimum of one screw on each side of support is also required
■Flex vent sections may be stretched up to 50% of their total length (eg. a
24"sectionmaybestretchedto36")
■Flex vent sections over 6 feet must fall within the limits set by the venting
graphandmusthaveaminimumverticalriseof3inchesperfootofex.
■Solid vent sections may be cut less than half way from the female end
■Venting components can be used in any combination of solid/rigid pipe or
expipeandinanyorientation(Maleconnectorscanfaceinanydirection)
Vent Terminations
Selecting A Termination Location
Choosing your vent termination location will help to determine whether
youneedtouseatopventorrearventreplace.Figure6a,below,shows
typicalreplacelocationsandtheventingoptionstheyprovide.
For a more detailed diagram of allowed termination locations, see Ap-
pendix A.
Cautions:
■ Vent terminations can be very hot. If the termination is less
than7feetaboveapublicwalkway,itshouldbettedwith
acertiedMontigoHeatGuard.(Partno.PTKOG).
■Donotobstruct,orattempttoconceal,theventtermination.
Theseactionswillaffecttheoperationofthereplace,
and may be hazardous.
■In heavy snow areas, take extra care to prevent snow
buildup from obstructing the vent termination.
Figure 6a. Fireplace locations and vent terminations.
Installing The Gas Line
ThegaslinemustbeinstalledbeforenishingtheHW42DF Fireplace.
Natural Gasrequiresaminimuminletgassupplypressureof5.5"W.C.
&amanifoldpressureof3.5"W.C.Provisionmustalsobemadefora
1/8"N.P.T.pluggedtappingandbeaccessiblefortestgaugeconnection
immediately upstream of the gas supply controls to the appliance. The
replacegasconnectionandthemainoperatinggasvalveislocated
behind the removable trim at the bottom of the unit and need only be
attachedtothegaslinewithanapprovedtting,asrequiredbythe
applicable installation codes.
To access the replace gas connection the main burner must be
removed as shown below in gure 5b.
•Onlyusegasshut-offvalvesapprovedforusebythestate,province,
region, or governing body, in which the appliance is being installed, or
as required by the applicable installation codes.
•Flexiblegasconnectorsmustnotexceed3feetinlength,unlessitis
allowable within applicable installation codes.
Note: After gas line is connected, each appliance connection,
valve and valve train must be checked while under normal
operating pressure with either a liquid solution, or leak
detection device, to locate any source of leak. Tighten any
areas where bubbling appears or leak is detected until
bubbling stops completely or leak is no longer detected.
DO NOT use a flame of any kind to test for leaks.
Figure 5a. Gas line access.
The appliance and its individual shut-off valve must be disconnected
from the gas supply piping system during any pressure testing of that
system at test pressures in excess of 1/2 psig (3.5 kPa).
The appliance must be isolated from the gas supply piping system by
closing its 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).
Burner Tray Gasket
Figure 5b. Gas line access.
Gasline Acces
0.875 dia.
7
to center
2

Page 6
HW42DF Gas Fireplace
Part No. XG0191 - 031010
Installation
Installing Terminations with Built-In Frames
Installing Terminations with MSR Frames
1. Frametheterminationopeningto12"x12".
2. Fasten the termination to the studs using a minimum of 4 screws.
1. Frametheterminationopeningto11"x11".
2. Fasten the termination to the studs using a minimum of 4
screws.
Installing Terminations with MOSR Frames
MOSR
1. Frametheterminationopeningto12"x12".
2. FastentheMOSRframetotheinteriorsideofthestudsusinga
minimum of 4 screws.
3. InserttheterminationintotheMOSRframeasshownhere,and
attach by screwing through the four pilot holes in the termination.
MSR
PTO-3 (5"/8")
PTO-3F (5"/8")
PTO-3 (5"/8")
PTKOG (5"/8")
1. Ensure that the two long mounting brackets are facing the bottom
ofthe termination.(See inset).Thiswill provide more heatprotection
at the top of the termination, where temperatures are highest.
2. Attach to the faceplate of the termination using four sheet metal
screws.
Installing Heat Guards over Terminations
Installing The Standoffs
To avoid elevated mantel temperatures, all HW42DF gas
replaces are required to have the supplied standoffs installed.
The replace is supplied with two standoffs. Bend and install these
standoffsontopofthereplaceensuringthattheheightofthestandoff
maintainsa6.5"clearance.
Figure 6b. Installing the stando's.
Installing the Nailing Flange
Extension, or Non-Combustible
material
The Nailing Flange Extension is supplied with all Montigo Flush face
gasreplaces.ThisExtensionisrequired,unlessNon-combustible
materials are used in its place, (see Figure 25).
Oncethereplaceismovedintotheframedopening,thesupplied
nailing extension, or Non-combustible material must be placed along
thetopedgeofthereplace.Thiscanbenailedorscrewedinplace
to the framing, as illustrated below.
Figure 5a. Installing a MTO / PTO termination.
Figure 5b. Installing a MTO / PTO termination with the MSR frame.
Figure 5c. Installing a MTO / PTO termination with the MOSR frame.
1212
12
Figure 5d. Installing a PTO termination heat guard.
11
11
12
12
Figure 6c. Installing the Nailing Flange Extension, or Non-combusti-
ble materials above replace.

Page 7
HW42DF Gas Fireplace
Part No. XG0191 - 031010
Installation
Figure 8a. Flue cap installation for Rear Vented replace.
Figure 8b. Flue collar installation for Rear Vented replace.
5”Inner Flue Cap
8”Outer Flue Cap
5”Inner Flue Collar
8”Outer Flue Collar
Figure 7b. Flue collar installation, Top Vented HW42DF replace.
5”Inner Flue Cap
8”Outer Flue Cap
5”Inner Flue Collar
8”Outer Flue Collar
Figure 8b. Flue collar installation, Rear Vented HW42DF replace.
Converting to Top Vent/ Rear Vent
HW42DF Top Vent
Use the following instructions to convert a HW42DF,for Top Vent use:
1. Installthe5"inneruecapontherearueoutletandsecurethe
capinplacewithvescrews,asshowningure7a.
2. Installthe8"outeruecapontherearueoutlet,andsecureit
withvescrews,asshowningure7a.
3. Installtheuegasketmaterialanduecoverplateontherearvent
outlet . Fasten the plate with four screws, as illustrated below.
4. Installthe5"inneruecollarandthe8"outeruecollarinplace
on the top vent outlet using 5 screws, as illustrated below.
HW42DF Rear Vent
Use the following instructions to convert an HW42DF, for Rear Vent use:
1. Installthe5"inneruecaponthetopueoutletandsecurethe
capinplacewithvescrews,asshowningure8a.
2. Installthe8"outeruecaponthetopueoutlet,andsecureit
withvescrews,asshowningure8a.
3. Installtheuegasketmaterialanduecoverplateonthetopvent
outlet.Fastentheplatewithfourscrews,asillustratedingure8b.
4. Installthe5"inneruecollarandthe8"outeruecollarinplace
on the rear vent outlet using 5 screws, as illustrated below.
Top Vent Venting Runs
FortheHW42DFTop Vent,therearetwotypesofinstallations:A)Through-
The-Wall Installations and B) Vertical (Through-The-Roof) Installations.
A) Through-The-Wall Installations
Before you install any venting, you must determine whether the venting
runwillbeacceptable.Unacceptableventingcanaffectthereplace's
combustion.
The Venting Graph
Measuretheverticalheightfromthereplacehearthtothecentreof
theterminationandthehorizontalrunfromthefromthereplaceue
collartothewallangeofthetermination.PlotontheVentingGraph
(Fig.9a)withan'X'.
Ifthe'X'fallsonorabovethetopboundaryoftheshadedarea,the
installation is acceptable.
Important:
Aninspectionoftheexplosionreliefappersanddoormustbe
madepriortolightingthereplace.Thiswillensurethedoorgas-
keting material will provide an adequate seal during operation.

Page 8
HW42DF Gas Fireplace
Part No. XG0191 - 031010
B
C
A
42” NG
45”
36
5/8 NG
PEL
Installation
Example A: (Acceptable Installation)
If the vertical dimension from the hearth is 66" and the horizontal run to
the wall flange of the vent termination is 60", this would be an acceptable
installation.
Example B: (Acceptable Installation)
If the vertical dimension from the hearth is 108" and the horizontal run to
the wall flange of the vent termination is 172", this would be an acceptable
installation.
Example C: (Unacceptable Installation)
If the vertical dimension from the floor of the fireplace is 60" and the
horizontal run to the wall flange of the vent termination is 144", this would
NOT be an acceptable installation.
NOTES: All dimension lengths for vertical or horizontal runs are
measured from centre of the vent pipe.
Venting runs must fall within the limits set by the venting
graph (see Figure 7).
Available Top Vent Components
The following venting components are available for he HW42DF Top Vent.
Example 1:
ForourshortestventingcongurationusecomponentsAandE(see
Figure 10).
Figure 10. Typical Top Vent installation. If the 90° elbow is installed
directly on the replace, for height to the center of the
termination see chart on page 3.
Horizontal Venting
Figure11. Typical Top Vent installation. The solid sections can be used in
various combinations to obtain the desired vent run. The vent
run must fall within the limits set by the venting graph.
90° Elbow
PEXT Section
Termination
Example 2:
Rigidsectionsandanelbowusedinconjunctionwith3ft.exsection
(PFL-3)will,whenextendedinavefootchase,allowforamaximum
horizontalrunoftwelveandone-halffeetfromthecentreofthereplace
tooutsidewallandaminimumof7'6"whenretractedinoppositedirection
(see Figure 12 and 13).
"C"exsectionsand"D"rigidsectionsmaybeusedinconjunctionwith
one another to obtain different possible horizontal length installations.
NOTE: Flex section with no vertical rise must not exceed maximum
horizontal length of 3 feet (see Figure 14). Flex runs over 3 feet must
fall within the limits set by the venting graph, and must have a minimum
verticalriseof3"perfootofex.
Figure 9b. HW42DF Top Vent Venting Graph
PowerVentmodels,EDVRR&EDVRW
to be used within the shaded area of
graph.(SeeBELOWforapplicable
Product information).
5" / 8" Venting
A - TerminationP TO-3(3"Length)
PTO-3F(3"Length)
B - Stucco Kits MSR (Stucco Frame)
MOSR(StuccoCan)
BSR ( Brick Can)
C - Flex Sections PFL-1(12"Section)
PFL-2(24"Section)
PFL-3(36"Section)
PFL-4(48"Section)
D - Rigid
Sections
PEXT-1(12"m/fSection)
PEXT-2(24"m/fSection)
PEXT-3(36"m/fSection)
PEXT-4(48"m/fSection)
E - Elbows PEL-90MM (m/m 90° Elbow)
PEL-90FF (f/f 90° Elbow)
PEL-90FM (f/m 90° Elbow)

Page 9
HW42DF Gas Fireplace
Part No. XG0191 - 031010
Installation
Figure 12. Extended Installation using a combination of solid and ex
venting. Use the vent graph to determine your allowable
run, then select appropriate components.
Figure 13. Retracted Installation using a combination of solid and ex
venting. Use the vent graph to determine your allowable
run, then select appropriate components.
RHS8
RHS8
Figure 14. Horizontal ex installation with no vertical rise.
45”
Min
.
RHS8
42”Min.
B. Vertical (Through-The-Roof) Installations
 Minimumclearances2"fromventtoallcombustiblematerialsmust
be maintained.
A maximum of two offsets (each offset has two 90° bends) may be
made and shall not exceed total length of 25% of the vertical vent
height, when measured center to center of piping.
Example: Typical vent installation.
20' vertical vent
2 - 2' offsets required
25% of 20' = 5' max. offset allowed
This venting configuration meets requirements.
Figure 16. Vertical venting with 1 oset (1 oset= two 90° bends).
5" / 8" Venting
A - Termination PVTK-1
B - Flex Sections PFL-1(12"Section)
PFL-2(24"Section)
PFL-3(36"Section)
PFL-4(48"Section)
C - Rigid Sections PEXT-1(12"m/fSection)
PEXT-2(24"m/fSection)
PEXT-3(36"m/fSection)
PEXT-4(48"m/fSection)
D - Support Ring
&Plate
PSPXT-8
E - Firestop PS-8
F - Roof Flashing PRF-7 (1/12 - 7/12 pt.)
PRF-7 (7/12 - 12/12 pt.)
G - Adaptor / Vent
Reducer
PVA5487(5"/8"to4"/7")

Page 10
HW42DF Gas Fireplace
Part No. XG0191 - 031010
Installation
Figure 17. Vertical venting with 2 osets (1 oset= two 90° bends).
C. Vertical (Corner) Installations
 AttachanPEL-45(45°elbow)directlyontotheuecollar.Cutthe
PXT-18tosuit,andattachittothePEL-45.Slidethereplaceinto
position and attach to the termination.
Important: Some models are not available to be
installed in a rear vent application. Please refer to
the model specications on page 2 of this manual.
Figure 18. Corner installation.
Figure 19. Flex installation. (NG Models Only)
C. Vertical (Corner) Installations - 45° or less.
 UseanMTO-3/PTO-3terminationandanMFL-1/PFL-1orPFL-2/
PFL-2(12"or24"compressedlength)andaframe,ifappropriate.
Flex may be turned to obtain desired degree of angle required but
must not exceed 45°.
Note: Through the wall venting kits are also available for both
the Straight and the Corner Installation. The Kit includes a heat
sheild,aPFL-18(f/f)exiblepipe,andaterminationwithorwithout
a mounting frame.
PEL-45 Elbow
PEL-90 Elbow
PXT-18
Rear Vent Venting Runs
The HW42DF Rear Vent has Only One possible installation which
requires vertical lift. This installation requires that you install the RHS101
heat shield.
Heat Shield
The heat shield (RHS101) must be used on All installations through
the wall, at the point where the vent pipe connects to the termination.
With the heat shield, proper vent clearances can be maintained. The
heat shield is not included with the replace.
To installthe heat shield,slide one sectionover thevent pipe onthe inside
of the wall opening, with the circular portion inside the wall cavity. Screw
the shield in place over the wall opening. Install the second section on
the outside of the wall opening sliding the circular portion into the wall
opening.RefertoFigure22&Figure24.
B. Multi-Elbow Installations
Formoredifcultinstallationsituations,the HW42DF Rear Vent may be
installedwithtwo-90°elbowsandupto15'ofhorizontalrun.Ifusing
this installation option, you must adhere to the following guidelines:
 therst90°elbowmustbeplaceddirectlyontheuecollar
 youmusthaveaminimumverticalliftof50"(measuredfromthe
hearth)
your vent run must fall within the limits set by Figure 22.
Before you install any venting, you must determine whether the venting
runwillbeacceptable.Unacceptableventingcanaffectthereplace's
combustion.