International comfort products N9MP1 User manual

CARBON MONOXIDE POISONING AND FIRE
HAZARD.
Failuretofollowsafetywarningsexactlycould
result in serious injury, death, and/or property
damage.
This furnace is not designed for use in mobile
homes, trailers or recreational vehicles.
!WARNING
!
ELECTRIC SHOCK HAZARD
Failure to follow safety
warnings exactly could result
in serious injury and/or death.
Turn Off All Power Before
Servicing.
International Comfort Products, LLC
Lewisburg, TN 37091 U.S.A.
INSTALLER: Affix these instructions
on or adjacent to the furnace.
CONSUMER: Retain these
instructions for future reference.
WARNING
* Denotes Brands (C, H, T)
PrintedinU.S.A. 7/18/2005 440 01 1021 (01)
N9MP1 & N9MP2
*9MPD
FAN ASSISTED, DIRECT
VENT GAS FURNACE
SAFETY REQUIREMENTS
Recognizesafetyinformation. Thisisthesafety--alertsymbol !. Whenyouseethissymbolonthefurnaceandininstructionsmanualsbealertto
the potential for personal injury.
Understand the signal words DANGER, WARNING, or CAUTION. These words are used with the safety--alert symbol. DANGER identifies the
most serious hazards, those that will result in severe personal injury or death. WARNING signifies a hazard that could result in personal injury or
death. CAUTION is used to identify unsafe practices that could result in minor personal injury or product and property damage. Note is used to
highlight suggestions that will result in enhanced installation, reliability, or operation.
Installing and servicing heating equipment can be hazardous due to gas and electrical components. Only trained and qualified personnel should
install, repair, or service heating equipment.
Untrained service personnel can perform basic maintenance functions such as cleaning and replacing air filters. All other operations must be
performedbytrainedservicepersonnel. Whenworkingonheatingequipment,observeprecautionsintheliterature,ontags,andonlabelsattached
to or shipped with the unit and other safety precautions that may apply.
Follow all safety codes. In the United States, follow all safety codes including the current edition National Fuel Gas Code (NFGC) ANSI
Z223.1--2002/NFPA No.54--2002. InCanada,refertothecurrenteditionoftheNationalStandardofCanada NaturalGasandPropaneInstallation
Code (NSCNGPIC) CSA B149.1--05. Wear safety glasses and work gloves. Have fire extinguisher available during start--up and adjustment
procedures and service calls.
Theseinstructions coverminimumrequirementsandconformtoexistingnationalstandardsandsafetycodes. Insomeinstances,theseinstructions
exceedcertainlocalcodesandordinances,especiallythosethatmaynothavekeptupwithchangingresidentialconstructionpractices. Werequire
these instructions as a minimum for a safe installation.
Table of Contents
1. Safe Installation Requirements 3...................
2. Installation 4..................................
3. Combustion & Ventilation Air 7....................
4. Vent & Combustion Air Piping 11...................
5. Concentric Vent Termination 29....................
6. Gas Supply and Piping 31........................
7. Electrical Wiring 36............................
8. Ductwork and Filter 38..........................
9. Checks and Adjustments 41......................
10. Furnace Maintenance 43........................
11. Sequence of Operation & Diagnostics 44............
Technical Support 47.............................

2440 01 1021 01
START--UP CHECK SHEET
For 90+ Furnace
(Keep this page for future reference)
Dealer Name:
Address:Business Card Here
City, State(Province), Zip or Postal Code:
Phone:
Owner Name:
Address:
City, State(Province), Zip or Postal Code:
Model Number:
Serial Number:
Type of Gas: Natural: LP:
Which blower speed tap is used?
(Heating) (Cooling)
Temperature of Supply Air: (°F) or(°C)
Temperature of Return Air: (°F) or(°C)
Rise (Supply Temp.--Return Temp.): (°F) or(°C)
Filter Type and Size:
Fan “Time ON” Setting:
Fan “Time OFF” Setting:
Manual Gas Shut--Off Upstream
of Furnace/Drip--Leg? YES NO
Condensate Drain Connected? YES NO
Condensate Drain Trapped? YES NO
Transition Pressure switch hose relocated for U/D/H
Application? YES NO
Blower Speed Checked? YES NO
All Electrical Connections Tight? YES NO
Gas Valve turned ON? YES NO
Measured Line Pressure When Firing Unit:
Calculated Firing Rate:(See Checks and Adjustments Sec-
tion).
Temperature Rise (supply--return temperature):(°F)
Measured Manifold Gas Pressure:
Static Pressure (Ducts): Supply Air Return
Date of Start--Up:
CO ?
CO2 ?
Dealer Comments:

3
440 01 1021 01
1. Safe Installation Requirements
FIRE, EXPLOSION, AND ASPHIXIATION HAZARD
Improper adjustment, alteration, service,
maintanence or installation could cause death,
personal injury and/or property damage.
Installation or repairs made by unqualified persons
could result in hazards to you and others.
Installation MUST conform with local codes or, in
the absence of local codes, with codes of all
governmental authorities having jurisdiction.
The information contained in this manual is
intended for use by a qualified service agency that
is experienced in such work, is familiar with all
precautions and safety procedures required in
such work, and is equipped with the proper tools
and test instruments.
!WARNING
NOTE: This furnace is design--certified by the CSA International
(formerly AGA and CGA) for installation in the United States and
Canada. Refer to the appropriate codes, along with this manual,
for proper installation.
·Use only the Type of gas approved for this furnace (see
RatingPlateonunit).Overfiringwillresultinfailureofheat
exchanger and cause dangerous operation. (Furnaces
can be converted to L.P. gas with approved kit.)
·Installthisfurnaceonlyinalocationandpositionasspeci-
fied in “2. Installation” of these instructions.
·Provideadequatecombustionandventilationairtothefur-
naceasspecifiedin“3.CombustionandVentilationAir” of
these instructions.
·Combustionproducts must be discharged outdoors.Con-
nectthis furnacetoan approvedventsystemonly,asspe-
cified in “4. Vent and Combustion Air Piping” of these
instructions.
·Never test for gas leaks with an open flame. Use a com-
mercially available soapsolution made specifically for the
detectionofleakstocheckall connections,as specifiedin
“6. Gas Supply and Piping, Final Check” of these instruc-
tions.
·Always install furnace to operate within the furnace’s in-
tended temperature--rise range with a duct system which
hasanexternalstaticpressurewithintheallowablerange,
as specified in “Technical Support Manual” of these in-
structions. See furnace rating plate.
·When a furnace is installed so that supply ducts carry air
circulated by the furnace to areas outside the space con-
tainingthefurnace,thereturnairshallalsobehandledbya
duct(s) sealed to the furnace casing and terminating out-
side the space containing the furnace.
·A gas--fired furnace for installation in a residential garage
must be installed as specified in “2. Installation” of these
instructions.
·This furnace is not to be used for temporary heating of
buildings or structures under construction.
·This furnace is NOT approved for installation in mo-
bile homes, trailers or recreation vehicles.
·Seal around supply and return air ducts.
·Install correct filter type and size.
·Unit MUST be installed so electrical components are pro-
tected from direct contact with water.
Safety Rules
Your unit is built to provide many years of safe and dependable
serviceprovidingitisproperlyinstalledand maintained.However,
abuse and/or improper use can shorten the life of the unit and
create hazards for you, the owner.
A. The U.S. Consumer Product Safety Commission encourages
installation of carbon monoxide alarms. There can be various
sources of carbon monoxide in a building or dwelling. The
sources could be gas--fired clothes dryers, gas cooking
stoves, water heaters, furnaces, gas--fired fireplaces, wood
fireplaces.
Carbon monoxide can cause serious bodily injury and/or
death. Carbon monoxide or “CO” is a colorless and odorless
gas produced when fuelis not burned completely or whenthe
flame does not receive sufficient oxygen.
Therefore,tohelpalertpeopleofpotentiallydangerouscarbon
monoxide levels, you should have a commercially available
carbon monoxide alarm that is listed by a nationally recog-
nizedtestingagencyinaccordancewithUnderwritersLabora-
tories Inc. Standard for Single and Multiple Station Carbon
Monoxide Alarms, ANSI/UL 2034 or the CSA 6.19--01 Resi-
dential Carbon Alarming Devices installed and maintained in
thebuildingordwellingconcurrentlywiththegas--firedfurnace
installation(seeNotebelow).Thealarmshouldbeinstalledas
recommended by the alarm manufacturer’s installation in-
structions.
B. There can be numerous sources of fire or smoke in a building
or dwelling. Fire or smoke can cause serious bodily injury,
death, and/or property damage. Therefore, in order to alert
peopleofpotentiallydangerousfireorsmoke,youshouldhave
fireextinguisherandsmokealarmslistedbyUnderwritersLab-
oratories installed and maintained in the building or dwelling
(see Note below).
Note: The manufacturer of your furnace does not test any alarms
and makes no representations regarding any brand or type
of alarms.
C. Toensuresafeandefficientoperationofyourunit,youshould
do the following:
1. Thoroughly read this manual and labels on the unit. This
will helpyou understand how yourunit operates and the haz-
ards involved with gas and electricity.
2. Do not use this unit if any part has been under water. Im-
mediatelycallaqualifiedservicetechniciantoinspecttheunit
andtoreplaceanypartofthecontrolsystemandanygascon-
trol which has been under water.
3. Never obstruct the vent grilles, or any ducts that provide
air to the unit. Air must be provided for proper combustion
and ventilation of flue gases.

4440 01 1021 01
Frozen Water Pipe Hazard
WATER DAMAGE TO PROPERTY HAZARD
FaiIure to protect against the risk of freezing may
result in property damage.
Do not leave your home unattended for long periods
during freezing weather without turning off water
supply and draining water pipes or otherwise
protecting against the risk of frozen pipes and
resultant damage.
!CAUTION
Your furnaceis designed solely toprovide a safe and comfortable
living environment. The furnace is NOT designed to ensure that
water pipes will not freeze. It is equipped with several safety de-
vices that are designed to turn the furnace off and prevent itfrom
restarting in the event of various potentially unsafe conditions.
If your furnace remains off for an extended time, the pipes in your
home could freeze and burst, resulting in serious water damage.
If the structure will be unattended during cold weather you should
take these precautions.
1. Turnoffthewatersupplytothestructureanddrainthewater
lines if possible and add an antifreeze for potable water to
drain traps and toilet tanks. Open faucets in appropriate
areas. -- or --
2. Have someone check the structure frequently during cold
weather to make sure it is warm enough to prevent pipes
from freezing. Instruct them on a service agency to call to
provide service, if required.
-- or --
3. Installareliableremotesensingdevicethatwillnotifysome-
body of freezing conditions within the home.
Winter Shutdown
Ifyougoawayduringthewintermonthsanddo notleave theheat
oninyourhome,theplastictransitionboxandthecondensatetrap
on the furnace must be protected from freeze damage.(See
Figure 9 trough Figure 18)
1. Disconnect the 5/8²ODrubber hose from the vent drain fit-
ting that is located downstream of the combustion blower.
Insertafunnelintothehoseandpourfour(4)ouncesofsani-
tary type (RV) antifreeze into the condensate trap. Recon-
nect the 5/8²OD rubber hose to the stub on the vent drain
fitting. Secure with the hose clamp.
2. Disconnect the 3/4²OD rubber hose from the condensate
trap. Insert a funnel into the hose and and pour four(4)
ouncesofsanitarytype(RV)antifreezeintotheplasticTran-
sition box. Squeeze the hose together near the end and
quicklyreconnectthe3/4²ODrubberhosetothestubonthe
condensate trap. Secure with the hose clamp.
When you return home, your furnace will be ready to start, as it is
not necessary to drain the antifreeze from the furnace.
2. Installation
CARBON MONOXIDE POISONING HAZARD
Failure to properly vent this furnace or other
appliances could result in death or personal injury.
This furnace can NOT be common vented or
connected to any type B, BW or L vent or vent
connector, nor to any portion of a factory--built or
masonry chimney. If this furnace is replacing a
previously common-vented furnace, it may be
necessarytoresizetheexisting ventandchimneyto
prevent oversizing problems for the other
remaining appliance(s). See Venting and Combus-
tion Air Check in Gas Vent Installation section.This
furnace MUST be vented to the outside.
!WARNING
Location and Clearances
1. RefertoFigure 1orFigure 2fortypicalinstallationandba-
sic connecting parts required. Refer to Figure 4 for typical
horizontaldirectventinstallationandbasicconnectingparts
required. Supply and return air plenums and duct are also
required.
Vent Pipes MUST be
supportedHorizontally
and Vertically
*8²Min.
20¢Max.
in same atmospheric
zone
*8²Min.
20¢Max.
in same
atmospheric
zone
Coupling on endsof
exhaust pipe. Total
pipe & coupling out-
side structure = 8²
Figure 1 Typical Upflow Installation
Aluminum or non-rusting shield recommended. (See
Vent Termination Shielding for dimensions).
*Increase minimum from 8²to 18²for cold climates (sustained temperatures below
0°F).
DISCHARGE AIR
25--23--33
Inlet Pipe (not
used on Single
Pipe model)

5
440 01 1021 01
*8²Min.
20¢Max.
in same
atmosphericzone
Figure 2 Typical Downflow Installation
Vent Pipes MUST be
supported Horizontally
and Vertically
*Increase minimum from 8²to 18²for cold climates (sustained temperatures
below 0°F).
See Vent Termination
Shielding inVentSection.
*8²Min.
20¢Max.
in same
atmosphericzone
8²Min.
Coupling on inside
and outside of wall
to restrain vent pipe
25--23--33a
Inlet Pipe
(not used on
Single Pipe
model)
CARBON MONOXIDE POISONING HAZARD.
FaiIure to follow safety warnings exactly could
result in death or personal injury.
Do NOT operate furnace in a corrosive atmosphere
containing chlorine, fluorine or any other damaging
chemicals, which could shorten furnace life.
Refer to 3. Combustion & Ventilation Air section,
Contaminated Combustion Air for combustion air
evaluation and remedy.
!WARNING
2. Iffurnaceisareplacement,itisusuallybesttoinstallthefur-
nace where the old one was. Choose the location or evalu-
atetheexistinglocationbasedupontheminimumclearance
and furnace dimensions (Figure 3).
FROZEN AND BURST WATER PIPE HAZARD
FaiIure to protect against the risk of freezing may
result in property damage.
Special precautions MUST be made if installing
furnace in an area which may drop below freezing.
This can cause improper operation or damage to
equipment. If furnace environment has the potential
of freezing, the drain trap and drainline must be
protected. The use of electric heat tape or RV
antifreeze is recommended for these installations.
(See “Condensate Trap Freeze Protection Section”)
!CAUTION
Do NOT operate furnace in a corrosive atmosphere
containing chlorine, fluorine or any other damaging
chemicals. Refer to Combustion & Ventilation Air section,
Contaminated Combustion Air.
Installation Requirements
1. Install furnace level.
2. ThisfurnaceisNOTtobeusedfortemporaryheatofbuildings
or structures under construction.
3. Install the vent pipes as short as practical. (See Gas Vent
Installation section).
4. DoNOTinstallfurnacedirectlyoncarpeting,tileorothercom-
bustible material other than wood flooring.
5. Maintainclearanceforfiresafetyandservicing.Afrontclear-
anceof30²isminimumforaccessto theburner,controlsand
filter. See clearance requirements in Figure 3.
6. Use a raised base if the floor is damp or wet at times.
7. Residential garage installations require:
·Burnersandignitionsourcesinstalledatleast18²(457mm)
above the floor.
·Furnace must be located or physically protected from pos-
sible damage by a vehicle.
8. Ifthefurnaceistobesuspendedfromthefloorjoistsinabase-
ment ora crawl spaceor the rafters inan attic, it is necessary
to use steel pipe straps or an angle iron frame to attach the
furnace. Thesestraps should be attached tothe furnace with
sheet metal screws and to the rafters or joists with bolts. The
preferred method is to use an angle iron frame bolted to the
rafters or joists.
9. Localcodesmayrequireadrainpanundertheentirefurnace
and condensate trap when the furnaceis installed in attic ap-
plication.
This furnace may be used for construction heat provided that all
the following conditions are met:
·The furnace is permanently installed with all electrical wir-
ing,piping,venting andductinginstalledaccordingtothese
installationinstructions. Areturnairductisprovided,sealed
to the furnace casing, and terminated outside the space
containing the furnace. This prevents a negative pressure
condition as created by the circulating air blower, causing a
flame rollout and/or drawing combustion products into the
structure.
·Thefurnaceiscontrolledbyathermostat. Itmaynotbe“hot
wired” to provide heat continuously to the structure without
thermostatic control.
·Cleanoutsideairisprovidedforcombustion. Thisistomini-
mize the corrosive effects of adhesives, sealers and other
construction materials. It also prevents the entrainment of
drywall dust into combustion air, which can cause fouling
and plugging of furnace components.
·The temperature of the return air to the furnace is main-
tainedbetween55°F(13°C)and80°F(27°C),withnoeve-
ningsetbackorshutdown. Theuseofthefurnacewhilethe
structure is under construction is deemed to be intermittent
operation per our installation instructions.
·Theairtemperatureriseiswithintheratedriserange onthe
furnace rating plate, and the firing rate has been set to the
rating plate value.
·The filters used to clean the circulating air during the
construction process must be eitherchanged or thoroughly
cleaned prior to occupancy.
·Thefurnace,ductworkandfiltersarecleaned as necessary
to remove drywall dust and construction debris from all
HVAC systemcomponents after construction is completed.
·Afterconstructioniscomplete,verifyfurnaceoperatingcon-
ditions including ignition, input rate, temperature rise and
venting according to these instructions.

215/8
13/8
811/16
25--23--36b
Figure 3 Dimensions & Clearances
TOP
F
G
E
H
AIR INTAKE
VENT (*9MPD)
ELECTRICAL
11/4
TRAP (COUNTERFLOW)
LEFT SIDE
GAS
VENT
413/16
11/16
AIR INTAKE
(ALTERNATE)
TRAP
UPFLOW/HORIZON-
TAL
THERMOSTAT
111/16
175/16
241/16
283/4
297/8
3111/16
1311/16
1913/16
21/4
131/4
17/8215/824
47/8
7
FRONT
A
B
DBOTTOM
37/8
231/8
23/8
AIR INTAKE
(ALTERNATE)
RIGHT SIDE
TRAP (COUNTERFLOW)
ELECTRICAL
VENT
TRAP
UPFLOW/HORIZONTAL
THERMOSTAT
11/4
27/8
281/2181/23/4
TYP.
45/16
11/16
GAS
413/16
111/16
175/16
111/16
273/16
297/8
215/8
3311/16
17/8
913/16
13/16
47/8
21/4
24
40
191/4
7
ALL DIMENSIONS IN INCHES
Drawing is representative,
but some models may vary
NOTE: Evaporator “A” coil drain pan dimensions
may vary from furnace duct opening size. Always
consult evaporator specifications for duct size
requirements.
Furnace is designed for bottom return or side
return.
Return air through back of furnace is NOT allowed.
C
* Dentoes Brand
6440 01 1021 01
MINIMUM CLEARANCES TO
COMBUSTIBLE MATERIALS FOR ALL UNITS
REAR 0
FRONT(combustionairopeningsin
furnace and in structure) 3²
Required For Service *24²
ALL SIDES Of SUPPLY PLENUM 1²
SIDES 0
VENT 0
TOP OF FURNACE 1²
*30²clearance recommended forfurnace removal.
Horizontal position: Line contact is permissible only between
linesformed by intersections oftop and two sides of furnace
jacket, and building joists, studs or framing.
U
n
i
t
C
a
b
i
n
e
t
B
o
t
t
o
m
T
o
p
Unit Cabinet Bottom Top
U
n
i
t
Capacity A B C D E F G H
N9MP1050B12B 151/214 13/8125/8-- -- -- -- -- -- -- --
N9MP1075B12B 151/214 13/8125/8-- -- -- -- -- -- -- --
N9MP1080F16B 191/8175/821/8143/4-- -- -- -- -- -- -- --
N9MP1100F14B 191/8175/821/8143/4-- -- -- -- -- -- -- --
N9MP1100J20 223/4211/4115/16 183/4-- -- -- -- -- -- -- --
N9MP1125J20 223/4211/4115/16 183/4-- -- -- -- -- -- -- --
N9MP2050B12 151/214 13/8125/8-- -- 41/2-- -- 73/4
N9MP2075B12B 151/214 13/8125/8-- -- 41/2-- -- 73/4
N9MP2080F16B 191/8175/821/8143/4-- -- 41/2-- -- 91/2
N9MP2100F14B 191/8175/821/8143/4-- -- 41/2-- -- 91/2
N9MP2100J20B 223/4211/4115/16 183/4-- -- 41/2-- -- 113/8
N9MP2125J20B 223/4211/4115/16 183/4-- -- 41/2-- -- 113/8
*9MPD050F12B 191/8175/821/8143/443/841/221/291/2
*9MPD075F12B 191/8175/821/8143/443/841/221/291/2
*9MPD080J16B 223/4211/4115/16 183/443/841/225/8113/8
*9MPD100J14B 223/4211/4115/16 183/443/841/225/8113/8
*9MPD100J20B 223/4211/4115/16 183/443/841/225/8113/8
*9MPD125L20B 241/223 7/16 23 43/841/221/4121/4

7
440 01 1021 01
Installation Positions
Thisfurnacecanbeinstalledinanupflow, horizontal (eitherleftor
right) or downflow airflowposition. DO NOT installthis furnace on
itsback.Fortheupflowposition,thereturnairductworkcanbeat-
tached to either the left or right side panel and/or the bottom. For
horizontalanddownflowpositions,thereturnairductworkmustbe
attached to thebottom. The return air ductwork must never beat-
tached to the back of the furnace.
Furnace Installation Considerations
Theinstallationofthefurnaceforagivenapplicationwilldictatethe
positionofthefurnace,theairflow,ductworkconnections,ventand
combustion air piping. Consideration must be given to the follow-
ing:
Condensate Trap and Drain Lines
The supplied condensate trap must be attached to the furnace
side panel on either the left or right side. For horizontal installa-
tions, the drain trap is vertically attached to the side panel below
the furnace. A minimum clearance of 6²below the furnace is re-
quired for the condensate trap. Downward slope of the conden-
satedrainlinefromthecondensatetrapto the drain locationmust
be provided. Adequate freeze protection of the drain trap and the
drainlinemustbeprovided.See“CondensateDrainTrap”section
for further details.
Leveling
Proper leveling of the furnace must be provided to insure proper
drainageofthecondensatefromthefurnace.Thefurnacemustbe
leveltowithin1/4²fromfronttobackandfromsidetosideforupflow
and downflow installations or top to bottomfor horizontal installa-
tions.
Vent and Combustion Air Connections
On the Dual Certified furnace, the vent and combustion air pipes
attachtothefurnacethroughthetoppanelfortheupflowandhori-
zontal installations. For the downflow installation, the vent and
combustion air pipes attach to the furnace through the alternate
locations on the furnace side panels.
Note:OntheDirectVentfurnace,theventpipeattachestothefur-
nacethroughthesidepanels.Thecombustionairpipeattachesto
the top panel or to the alternate location on the side panel.
On the Single Pipe furnace, the vent pipe attaches to the furnace
through the furnace side panels.
Note: Repositioning of the combustion blower is required for the
vent pipeconnection to the furnacethrough the “right side” panel.
See “Vent and Combustion Air Piping” section for further details.
Horizontal Furnace Installation
Inlet Pipe (not used on Single Pipe model)
Typical Horizontal Installation
Figure 4
Vent
Pipe
Condensate
Trap
NOTE: 6²
²²
²bottom clearance required for condensate trap.
25--23--34
This furnace can be installed horizontally in an attic, basement,
crawlspace,alcove,orsuspendedfromaceilinginabasementor
utility room . See Figure 4. Do not install furnace on its back or in
thereverseairflowpositionsassafetycontroloperationwillbead-
versely affected.
If the furnace is to be installed in a crawl space, consult local
codes. A suitable concrete pad or blocks are recommended for
crawl space installation on the ground.
NOTE: 6²bottom clearance required for condensate trap.
Twentyfour(24)inchesbetweenthefrontofthefurnaceandadja-
centconstructionorotherappliancesMUSTbemaintainedforser-
vice clearance.
Keep all insulating materials clear from louvered door. Insulating
materials may be combustible.
The horizontal furnaces may be installed directly on combustible
wood flooring or supports as long as all required furnace clear-
ances are met. See Figure 4.
Thisfurnace MUSTNOTbeinstalleddirectlyoncarpetingortileor
other combustible material other than wood flooring or supports.
Forhorizontalinstallationoverafinishedlivingspace.Afieldfabri-
cated auxiliary drain pan with drain pipe is required to prevent
damage by overflow due to blocked condensate drain.
3. Combustion & Ventilation Air
For Single Pipe Installation
CARBON MONOXIDE POISONING HAZARD.
Failure to provide adequate combustion and
ventilation air could result in death or personal
injury.
Use methods described here to provide
combustion and ventilation air.
!WARNING
Furnaces require ventilation openings to provide sufficient air for
proper combustion and ventilation of flue gases. All duct or open-
ingsforsupplyingcombustionandventilationairmustcomplywith
thegas codes,orintheabsenceoflocalcodes,theapplicablena-
tional codes.
Combustion and ventilation air must be supplied in accordance
with one of the following:
1. Section8.3,AirforCombustionandVentilation,oftheNational
Fuel Gas Code, (NFGC), ANSI Z223.1--2002/NFPA 54--2002
in the U.S.,
2. Sections7.2,7.3,7.5,7.6,7.7,and7.8ofNationalStandardof
Canada, Natural Gas and Propane Installation Code
(NSCNGPIC), CSA B149.1--05 in Canada,
3. Applicable provisions of the local building code.
This furnace can NOT be common vented or connected to any
typeB,BWorLventorventconnector,nortoanyportionofafacto-
ry--builtormasonrychimney.MultistoryventingisNOTpermitted.
Ifthisfurnaceisreplacingapreviouslycommon-ventedfurnace,it

8440 01 1021 01
may be necessary to resize the existing vent and chimney to pre-
vent oversizing problems for the other remaining appliance(s).
See “Venting and Combustion Air Check” in this section.This fur-
nace MUST be vented to the outside.
When the installation is complete, check thatall appliances have
adequate combustion air and are venting properly. See Venting
AndCombustionAirCheck in“4. Gas VentInstallation”Section in
this manual.
Outdoor Combustion Air Method
Aspacehavinglessthan50cubicfeetper1,000BTUHinputrating
forallgasappliancesinstalledinthespacerequiresoutdoorairfor
combustion and ventilation.
Air Openings and Connecting Ducts
1. Total input rating for all gas appliances in the space MUST be
considered when determining free area of openings.
2. Connect ducts or openings directly to the outdoors.
3. When screens are used to cover openings, the openings
MUST be no smaller than 1/4²mesh.
4. The minimum dimension of air ducts MUST NOT be less than
3².
5. When sizing a grille, louver, or screen use the free area of
opening.Iffreeareais NOT stampedormarkedongrill orlou-
ver, assume a 20% free area for wood and 60% for metal.
Screens shall have a mesh size not smaller than 1/4².
Requirements
1. Providethespacewithsufficientairforpropercombustionand
ventilation of flue gases using horizontal or vertical ducts or
openings.
2. Figure 5illustrateshowtoprovidecombustionandventilation
airwhentwopermanentopenings,oneinletandoneoutlet,are
used.
a. One opening MUST commencewithin12²of the floor
and the second opening MUST commence within 12²of
the ceiling.
b. Size openings and ducts per Table 1.
Furnace
Furnace
Minimum One Inlet and One Outlet Air Supply is Required
May be in and Combination Shown
Inlet Air Opening Must be Within12²(300mm) of floor
Outlet Air Opening Must be Within12²(300mm) of ceiling
(1) 1 Square Inch (6cm2) per 4000 BTUH
(2) 1 Square Inch (6cm2) per 2000 BTUH
Outside Air (This is ONLY a guide. Subject to codes of country having jurisdiction.)
Figure 5
This installation NOT approved in Canada
Gas Vent
Gas Vent
Gas Vent
Gable Vent Gable Vent
Outlet
Air (1)
Outlet Air (1)
Outlet Air (1)
Furnace
Outlet
Air (2)
Optional Inlet Air (1)
Ventilated Attic Ventilated Attic
Ventilated Crawl Space
Inlet
Air (1) Inlet
Air (1) Inlet
Air (1)
Inlet
Air (2) Inlet
Air (2)
Top Above Insulation
Top Above Insulation
Soffit Vent
Soffit Vent
c. Horizontal duct openings require 1 square inch of free
areaper2,000BTUH(1,100mm2/kW)ofcombinedinput
for all gas appliances in the space (see Table 1).
d. Verticalductopeningsoropeningsdirectlycommunicat-
ing with the outdoors require 1 square inch of free area
per 4,000 BTUH (550 mm2/kW) for combined input of all
gas appliances in the space (see Table 1).
3. When one permanent outdoor opening is used, the opening
requires:
a. 1 sq. in of free area per 3,000 BTUH (700 mm2/kW) for
combined input of all gas appliances in the space (see
Table 1) and
b. notlessthanthesumoftheareasofallventconnectorsin
the space.
The opening shall commence within 12²of the top of the enclo-
sure.Appliancesshallhaveclearancesofatleast1²fromthesides
andback and6²fromthefront.Theopeningshalldirectlycommu-
nicatewiththeoutdoorsorshallcommunicatethroughaverticalor
horizontalducttotheoutdoorsorspaces(crawlorattic)thatfreely
communicate with the outdoors.
4. Combination of Indoor and Outdoor Air shall have:
a. Indoor openings that comply with the Indoor Combus-
tion Air Method below and
b. Outdoor openings located as required in the Outdoor
Combustion Air Method above and
c. Outdoor openings sized as follows.
1) Calculate the Ratio of all Indoor Space volume divid-
edbyrequiredvolumeforIndoorCombustionAirMeth-
od.
2) OutdooropeningsizereductionFactoris1minusthe
Ratio in 1) above.
3) Minimum size of Outdoor openings shall be the size
required in Outdoor Combustion Air Method above
multiplied by reduction Factor.

9
440 01 1021 01
Table 1 Free Area
BTUH Minimum Free Area Required for Each Opening orDuct to Outdoors
B
T
U
H
Input
Rating Two Horizontal Ducts
(sq. in./2,000 BTUH) Single Opening (sq. in./3,000 BTUH) Two Vertical Ducts or Openings (sq. in./4,000 BTUH) Round Duct (sq. in. /4,000 BTUH)
50,000 25 sq. in. 16.7 sq. in. 12.5 sq. in. 4²
75,000 37.5 sq. in. 25 sq. in. 18.75 sq. in. 5²
80,000 40 sq. in. 26.7 sq. in. 20.0 sq. in. 5²
100,000 50 sq. in. 33.3 sq. in. 25 sq. in. 6²
125,000 62.50 sq. in. 41.7 sq. in. 31.25 sq. in. 7²
EXAMPLE: Determining Free Area
Furnace
100,000
Furnace
100,000
+
+
Water Heater
30,000
Water Heater
30,000
=
=
Total Input
(130,000 ¸4,000)
Total Input
(130,000 ¸2,000)
= 32.5 Sq. In. Vertical
= 65 Sq. In. Horizontal
Indoor Combustion Air
!
CARBON MONOXIDE POISONING HAZARD.
Failure to supply adequate combustion air could
result in death or personal injury.
Most homes will require additional air from
outdoors for combustion and ventilation. A space
with at least 50 cubic feet per 1,000 BTUH input
rating or homes with tight construction may need
outdoor air, supplied through ducts, to
supplement air infiltration for proper combustion
and ventilation of flue gases.
WARNING
Standard and Known--Air--Infiltration Rate Methods
ã
ãã
ãNFPA&AGA
Indoorair ispermittedforcombustionandventilation,iftheStan-
dard or Known--Air--Infiltration Rate Method is used.
The Standard Method may be used, if thespace has no less vol-
ume than50 cubic feet per1,000 BTUH inputrating for all gas ap-
pliances installed in the space. The standard method permits
indoor air to be used for combustion and ventilation air.
The Known Air Infiltration Rate Method shall be used if the in-
filtration rate is known to be less than 0.40 air changes per hour
(ACH) and equal to or greater than 0.10 ACH. Infiltration rates
greater than 0.60 ACH shall not be used. The minimum required
volume of the space varies with the number of ACH and shall be
determined per Table 2 or Equations 1 and 2. Determine the
minimum required volume for each appliance in the space, and
add the volumes together to get the total minimum required vol-
ume for the space.
T
b
l
2
MINIMUM SPACE VOLUME FOR 100% COMBUSTION AND VENTILATION AIR FROM INDOORS (ft3)
Table 2 Other Than Fan-Assisted Total
(1,000’s Btuh) Fan-assisted Total (1,000’s Btuh)
ACH 30 40 50 50 75 100 125
0.60 1,050 1,400 1,750 1,250 1,875 2,500 3,125
0.50 1,260 1,680 2,100 1,500 2,250 3,000 3,750
0.40 1,575 2,100 2,625 1,875 2,813 3,750 4,688
0.30 2,100 2,800 3,500 2,500 3,750 5,000 6,250
0.20 3,150 4,200 5,250 3,750 5,625 7,500 9,375
0.10 6,300 8,400 10,500 7,500 11,250 15,000 18,750
0.00 NP NP NP NP NP NP NP
NP = Not Permitted
Table 2MinimumSpace Volumesweredeterminedbyusingthe
following equations from the National Fuel Gas Code ANSI
Z223.1/NFPA 54--2002, 8.3.3.2:
1. For other than fan--assisted appliances such as a draft
hood--equipped water heater,
1000 Btu / hr
21 ft3(Iother )
Volume other =ACH
2. For fan--assisted appliances such as this furnace,
1000 Btu / hr
15 ft3(Ifan )
Volume fan =ACH
If: Iother = combined input of all other than fan--assisted
appliances in Btu/hr
Ifan=combinedinputofallfan--assistedappliancesinBtu/hr
ACH = air changes per hour (ACH shall not exceed 0.60.)
The following requirements apply to the Standard Method andto
the Known Air Infiltration Rate Method.
·Adjoining rooms can be considered part of a space, if there
are no closable doors between rooms.
·Combining spaces on the same floor level. Each opening
shall have a free area of at least 1²2/1,000 BTUH (2,000
mm2/kW) of the total input rating of all gas appliances in the
space, but not less than 100 in2 (0.06 m2). Once opening

10 440 01 1021 01
shall commence within 12²(300 mm) of the ceiling and the
second opening shall commence within 12²(300 mm) of the
floor. Theminimumdimensionofairopeningsshallbeatleast
3²(80 mm).
·Combining spaces on different floor levels. The volumes of
spacesondifferentfloorlevelsshallbeconsideredcommuni-
cating spaces if connected by one or more permanentopen-
ingsindoorsorfloorshaving afreeareaofatleast2²2/1,000
Btuh (4,400 mm2/kW) of total input rating of all gas ap-
pliances.
·Anatticorcrawlspacemaybeconsideredaspace thatfreely
communicateswiththeoutdoorsprovidedthereareadequate
ventilationopeningsdirectlytooutdoors.OpeningsMUSTre-
mainopenandNOThaveanymeansofbeingclosedoff.Ven-
tilation openings to outdoors MUST be at least 1 square inch
offree areaper4,000BTUHoftotalinputratingforallgasap-
pliances in the space.
·In spaces that use the Indoor Combustion Air Method, in-
filtration should be adequate to provide air for combustion,
ventilation and dilution of flue gases. However, in buildings
withunusuallytightconstruction,additional airMUST bepro-
vided using the methods described in section titled Outdoor
Combustion Air Method:
·Unusually tight construction is defined as Construction with:
1. Walls and ceilings exposed to the outdoors have a con-
tinuous, sealed vapor barrier. Openings are gasketedor
sealed and
2. Doors and openable windows are weather stripped and
3. Other openings are caulked or sealed. These include
joints around window and door frames, between sole
plates and floors, between wall--ceiling joints, between
wall panels, at penetrations for plumbing, electrical and
gas lines, etc.
Ventilation Air
Someprovincialcodesandlocal municipalitiesrequireventilation
or make--up air be brought into the conditioned space as replace-
mentair.Whichevermethodisused,themixedreturnairtempera-
ture across the heat exchanger MUST not fall below 60°so that
flue gases will not condense excessively in the heat exchanger.
Excessivecondensationwillshortenthelifeoftheheatexchanger
and possibly void your warranty.
Venting and Combustion Air Check
Vent Check
Draft Hood
Vent Pipe
Match
Typical Gas
Water Heater
Figure 6
Ifflame pulls towardsdraft hood,this indicatessufficient
venting.
NOTE: When an existing Category I furnace is removed or re-
placed,theoriginalventingsystemmaynolongerbesizedtoprop-
erly vent the attached appliances, and to make sure there is
adequate combustion air for all appliances, MAKE THE FOL-
LOWING CHECK.
CARBON MONOXIDE POISONING HAZARD
Failure to follow the steps outlined below for each
appliance connected to the venting system being
placed into operation, could result in carbon
monoxide poisoning or death:
The following steps shall be followed for each
appliance connected to the venting system being
placed into operation, while all other appliances
connected to the venting system are not in
operation:
1. Seal any unused openings in the venting system.
2. Inspect theventing system for propersize and horizontal
pitch, as required in the National Fuel Gas Code, ANSI
Z223.1/NFPA 54 or CSA B149.1, Natural Gas and
Propane Installation Code and these instructions. Deter-
mine that there is no blockage or restriction, leakage,
corrosion and other deficiencies which could cause an
unsafe condition.
3. As far as practical, close all building doors and windows
andalldoorsbetweenthespaceinwhichtheappliance(s)
connected to the venting system are located and other
spaces of the building.
4. Close fireplace dampers.
5. Turn on clothes dryers and any appliance not connected
to the venting system. Turn on any exhaust fans, such as
range hoods and bathroom exhausts, so they are
operating at maximum speed. Do not operate a summer
exhaust fan.
6. Followthelightinginstructions.Placethe appliancebeing
inspected into operation. Adjust the thermostat so
appliance is operating continuously.
7. Test for spillage from draft hood equipped appliances at
thedrafthoodreliefopeningafter5minutesofmainburner
operation. Usethe flame ofa match or candle. (Figure 6)
8. If improper venting is observed, during any of the above
tests, the venting system must be corrected in
accordance with the National Fuel Gas Code, ANSI
Z223.1/NFPA 54 and/or CSA B149.1, Natural Gas and
Propane Installation Code.
9. After it has been determined that each appliance
connected to the venting system properly vents when
testedasoutlinedabove,returndoors,windows,exhaust
fans, fireplace dampers and any other gas--fired burning
appliance to their previous conditions of use.
!W
A
RNING
For Two Pipe Installation
This furnace can NOT be common vented or connected to any
typeB,BWorLventorventconnector,nortoanyportionofafacto-
ry--builtormasonrychimney.Ifthisfurnaceisreplacingaprevious-
ly common-vented furnace, it may be necessary to resize the
existing vent and chimney to prevent oversizing problems for the
other remaining appliance(s). See “Venting and Combustion Air
Check” in this section.This furnace MUST be vented to the out-
side.

11
440 01 1021 01
4. Vent and Combustion Air Piping
CARBON MONOXIDE POISONING HAZARD.
Failure to properly vent this furnace could result in
death or personal injury.
Use methods described here to provide combustion
and ventilation air.
!WARNING
SinglePipe(*9MP1Models)
This furnace is certified as a category IV appliance. This furnace
requiresventilationopenings to provide air for propercombustion
and ventilation of flue gases. All duct or openings for supplying
combustion and ventilation air must comply with the gas codesor
in absence of local codes, the applicable national codes.
Whentheinstallationiscomplete,seethe“VentingandCombus-
tion Air Check” in this manual.
Direct Vent (N9MP2 Models)
This furnace is certified as a category IV appliance. This furnace
uses outside air for combustion ONLY, it MUST be taken from the
sameatmosphericpressurezoneastheventpipe. SeeConfined
SpaceInstallationintheCombustionandVentilationAir inthis
manual.
Dual Certified (*9MPD Models)
This furnace is certified as a category IV appliance. This furnace
canbeinstalledasadirectventfurnaceusingoutsideair forcom-
bustionorthefurnacecanuseairfrominsidethestructureforcom-
bustion. The INLET air pipe is optional. If combustion air comes
frominsidethestructure,adequatemakeupairMUSTbeprovided
tocompensateforoxygenburned.SeeConfinedSpaceInstalla-
tion in the Combustion and Ventilation Air chapter. If combus-
tionairisdrawnfromoutsidethestructure,itMUST betakenfrom
the same atmospheric pressure zone as the vent pipe.
Contaminated Combustion Air
Installationsincertainareasortypesofstructureswillincreasethe
exposure to chemicals or halogens that may harm the furnace.
Thefollowingareasortypesofstructuresmaycontainorhaveex-
posure to the substances listed below. The installation must be
evaluated carefully as it may be necessary to provide outside air
for combustion.
·Commercial buildings.
·Buildings with indoor pools.
·Furnaces installed in laundry rooms.
·Furnaces installed in hobby or craft rooms.
·Furnaces installed near chemical storage areas.
·Permanent wave solutions for hair.
·Chlorinated waxes and cleaners.
·Chlorine based swimming pool chemicals.
·Water softening chemicals.
·De--icing salts or chemicals.
·Carbon tetrachloride.
·Halogen type refrigerants.
·Cleaning solvents (such as perchloroethylene).
·Printing inks, paint removers, varnishes, etc.
·Hydrochloric acid.
·Sulfuric Acid.
·Solvent cements and glues.
·Antistatic fabric softeners for clothes dryers.
·Masonry acid washing materials.
Vent and Combustion Air Piping Guidelines
This furnace is approved for venting with Schedule 40 PVC,
CPVC, ABS, Cellular Core pipe fittings and SDR--26 PVC.
Applicable ASTM Standards for Vent Materials
Materials Sch. 40
Pipe SDR Pipe
Cell
Core
Pipe Fittings Primer Solv.
Cement
ABS D1527 __ F628 D2468
&
D2661 -- -- D2235
PVC D1785 D2241 F891 D2466
&
D2665 F656 D2564
CPVC F441 F442 -- -- F438 -- -- F493
ABS to
PVC -- -- -- -- -- -- -- -- -- -- D3138
NOTE: 1)In Canada,allpipe,fittings&cementsmustconformto
applicable CSA standards or to local codes having jurisdiction.
2)Onlyusesolventcementsthataremarkedfor usewith
the specific venting material.
3) ABS to PVC transition joints REQUIRE a special sol-
vent cement that meets the requirements of ASTM D3138.
4) Referto ASTM D2855for general procedureto use for
cementing plastic pipe and fittings.
NOTE: Inorder to create aseal that allows futureremoval of pipe,
RTVsealantMUSTbeusedontheinletpipewhereitjoinstothe
furnace.
NOTE: All vent piping MUSTbeinstalledincompliancewithlocal
codesorordinances,theseinstructions,goodtradepractices,and
codes of country having jurisdiction.
1. Determinethebestroutingandterminationfortheventpipe
and air inlet pipe by referring to all of the instructions and
guidelines in this Section.
2. Determine the size required for the vent pipe and air inlet
pipe.
3. Loosely assemble all venting parts without adhesive (pipe
joint cement) for correct fit before final assembly.
4. Furnaceshallbeinstalledsoastopreventtheaccumulation
of condensate.
5. Use of vertical piping is preferred because there will be
some moisture in the flue gases that may condense as it
leavestheventpipe(SeeSpecialInstructionForHorizontal
Vents).
6. TheverticalventpipeMUSTbesupportedsothatnoweight
is allowed to rest on the combustion blower.
7. Exhaust vent piping or air inlet piping diameter MUST NOT
be reduced.
8. All exhaust vent piping from the furnace to termination
MUST slope upwards. A minimum of 1/4²per foot of run is
required to properly return condensate to the furnace drain
system.

12 440 01 1021 01
9. Use DWV type long radius elbows whenever possible, as
they provide for the minimumslope on horizontal runs and
they provide less resistance in the vent system.If DWV el-
bows cannot be used, usetwo, 45°elbows when possible.
On horizontal runs the elbowscan be slightly misaligned to
provide the correct slope.
10. All horizontal pipe runs MUST be supported at least every
fivefeetwithgalvanizedstraporotherrustresistantmateri-
al. NO sags or dips are permitted.
11. All vertical pipe runs MUST be supported every six feet
where accessible.
12. The minimum pipe run length is 2¢.
13. Thepipingcanberuninthesamechaseoradjacenttosup-
ply or vent pipe for water supply or waste plumbing. It can
also be runin the samechase with a ventfrom another 90+
furnace.
NOTE:InNO case can the piping be run in a chase where
temperatures can exceed 140°F. or where radiated heat
from adjacent surfaces would exceed 140°F.
14. The vent outlet MUST be installed to terminate in the same
atmospheric pressure zone as the combustion air inlet.
15. The vent system can be installed in an existing unused
chimney provided that:
·Both the exhaust vent and air intake run the length of the
chimney.
·No other gas fired appliance or fireplace (solid fuel) is
vented into the chimney.
·The top of the chimney MUST be sealed flush or crowned
uptosealagainstrainormeltingsnowsoONLYthepiping
protrudes.
·TheterminationclearancesshowninFigure 7&Figure 8
are maintained.
16. Furnace applications with vertical vents requiring vent di-
ameter increaser fittings must have increaser fittings
installed in vertical portion of the vent. Condensate will be
trapped in the vent if the vent diameter is increased prior to
havinganelbowturnedupward.Thiscouldcausenuisance
tripping of the pressure switch.
Combustion Air and Vent Piping Insulation
Guidelines
NOTE:Useclosedcell,neopreneinsulationorequivalent.IfFiber-
glass orequivalent insulation is used it must have a vapor barrier.
UseRvaluesof7upto10¢,R--11ifexposureexceeds10¢.IfFiber-
glass insulation is used, exterior to the structure, the pipe MUST
be boxed in and sealed against moisture.
1. Whentheventorcombustionairpipeheightabove theroof
exceeds30²,orifanexteriorvertical riserisusedonahori-
zontal vent to get above snow levels, the exterior portion
MUST be insulated.
2. When combustion air inlet piping is installed above a sus-
pended ceiling, the pipe MUST be insulated with moisture
resistant insulation such as Armaflex or other equivalent
type of insulation.
3. Insulate combustion air inlet piping when run in warm, hu-
mid spaces.
Sizing Combustion Air and Vent Pipe
Consult Table 3 or Table 4 to select the proper diameter exhaust
and combustion air piping. Exhaust and combustion air piping is
sized for each furnace Btuh size based on total lineal vent length
(on inlet or outlet side), and number of 90°elbows required. Two
45°elbows can be substituted for one 90°elbow. Theelbow orel-
bowsusedforventterminationoutsidethestructureAREcounted,
including elbows needed to bring termination above expected
snow levels. The elbow inside the furnace on the *9MPD IS NOT
included in the count.
Table 3 Pipe Diameter Table
N9MP1 & *9MPD Models
50,000, 75,000 & 80,000 Btuh Furnaces
40¢& (5) 90°elbows with 2²PVC pipe or
70¢& (5) 90°elbows with 3²PVC pipe
100,000 Btuh Furnace
40¢& (5) 90°elbows with 3²PVC pipe or
70¢& (5) 90°elbows with 3²PVC pipe &
Long Vent Kit (See Tech. Manual)
125,000 Btuh Furnace
40¢& (5) 90°elbows with 3²PVC pipe
Elbows are DWV Long Radius Type for 2²and 3²vents.
If more than five elbows are required, reduce the length of
both the inlet and exhaust pipes 5¢for each additional elbow
used.
NOTE: It is allowable to use larger diameter pipe and fitting than
shown in the tables but not smaller diameters than shown.
Table 4 Pipe Diameter Table
N9MP2 Models
50,000 & 80,000 Btuh Furnaces
40¢& (5) 90°elbows with 2²PVC pipe or
70¢& (5) 90°elbows with 3²PVC pipe
75,000 Btuh Furnaces
25¢& (3) 90°elbows with 2²PVC pipe or
40¢& (5) 90°elbows with 2²PVC pipe &
Long Vent Kit (See Tech. Manual) or
70¢& (5) 90°elbows with 3²PVC pipe
100,000 Btuh Furnace
40¢& (5) 90°elbows with 3²PVC pipe or
70¢& (5) 90°elbows with 3²PVC pipe &
Long Vent Kit (See Tech. Manual)
125,000 Btuh Furnace
40¢& (5) 90°elbows with 3²PVC pipe
Elbows are DWV Long Radius Type for 2²and 3²vents.
If more than five elbows are required, reduce the length of
both the inlet and exhaust pipes 5¢foreach additional elbow
used.
NOTE: It is allowable to use larger diameter pipe and fitting than
shown in the tables but not smaller diameters than shown.
For “Concentric Termination Kit” Venting table, see
“Section 11” in this manual.
Vent Termination Clearances
CARBON MONOXIDE POISONING.
Failure to properly vent this furnace could result in
death or personal injury.
Inlet and outlet pipes may NOT be vented directly
above each other.
!W
A
RNING
1. Determine termination locations based on clearancesspe-
cifiedinfollowingstepsandasshowninFigure 7,Figure 8,
Figure 20, through Figure 28.
For “Concentric Termination Kit” clearances, see Figure 29,
thru Figure 33 in “Section 5” in this manual.
2. ForSinglePipeInstallation,modelsN9MP1or*9MPD,refer
to Figure 8 for vent termination clearances.
3. ForDirectVentInstallation,modelsN9MP2or*9MPD,refer
to Figure 7 for vent termination clearances.

A
X
B
V
V
V
V
X
X
AIR SUPPLY INLET
VVENT TERMINAL AREA WHERE TERMINAL IS NOT PERMITED
A
B
B
B
B
B
C
DE
FJ
I
L
H
K
G
25--24--65--2
N
YY
X
M
V
O
Direct Vent Termination Clearance
Figure 7
13
440 01 1021 01
Item Clearance Description Canadian Installation (1) U.S. Installation (2)
AClearance above grade, veranda, porch, deck, balcony, or
anticipated snow level 12²(30cm) # 12²(30 cm)
BClearance to a window or door that may be opened 6²(15 cm) for appliances £10,000 BTUH (3kW), 12²(30
cm) for appliances > 10,000 Btuh (3 kW) and £100,000 Btuh
(30 kW), 36²(91 cm) for appliances > 100,000 Btuh (30 kW)
6²(15 cm) for appliances £10,000 BTUH (3kW), 9²(23 cm)
for appliances > 10,000 Btuh (3 kW) and £50,000 Btuh (15
kW), 12²(30 cm) for appliances > 50,000 Btuh (15 kW)
CClearance to a permanently closed window * *
DVertical clearance to a ventilated soffit located above the
terminal within a horizontal distance of 2¢(61cm) from the
centerline of the terminal
* *
EClearance to an unventilated soffit * *
FClearance to an outside corner * *
GClearance to an inside corner * *
HClearance to each side of the centerline extended above
electrical meter or gas service regulator assembly 3¢(91 cm) within 15¢(4.5 m) above the meter/regulator assembly 3¢(91 cm) within 15¢(4.5 m) above the meter/regulator assembly
IClearance to service regulator vent outlet 3¢(91 cm) *
JClearance to non--mechanical air supply inlet to building or
the combustion air inlet to any other appliance 6²(15 cm) for appliances £10,000 BTUH (3kW), 9²(23 cm) for appliances > 10,000 Btuh (3 kW) and £100,000 Btuh (30
kW) and £50,000 Btuh (15 kW), 12²(30 cm) for appliances
> 50,000 Btuh (15 kW)
6²(15 cm) for appliances £10,000 BTUH (3kW), 9²(23 cm)
for appliances > 10,000 Btuh (3 kW) and £50,000 Btuh (15
kW), 12²(30 cm) for appliances > 50,000 Btuh (15 kW)
KClearance to a mechanical air supply inlet 6¢(1.83 m) 3¢(91 cm) above if within 10¢(3m) horizontally
LClearance under a veranda, porch, deck, or balcony 12²(30 cm) + *
MClearance to each side of the centerline extended above or
below vent terminal of the furnace to a dryer or water heater
vent, or other appliance’s direct vent intake or exhaust.
12²(30 cm) 12²(30 cm)
NClearance from a plumbing vent stack 3¢(91 cm) 3¢(91 cm)
OClearance above a paved sidewalk or paved driveway located
on public property. 7¢(2.13 m) 7¢(2.13 m)
(1.) In accordance with the current CSA B149.1, Natural Gas and Propane Installation Code
(2.) In accordance with the current ANSI Z223.1/NFPA 54, National Fuel Gas Code
#18²(46 cm) above roof surface
+ Permitted only if veranda, porch, deck, or balcony is fully open on a minimum of two sides beneath the floor.
*ForclearancesnotspecifiedinANSIZ223.1/NFPA54or CSAB149.1,clearances shall beinaccordancewithlocalinstallationcodesandtherequirementsofthegassupplier andthemanufacture’sinstallation
instructions.
** A vent shall not terminate directly above a sidewalk or paved driveway that is located between two single family dwellings and serves both dwellings.
Notes:
1. The vent for this appliance shall not terminate
a. Over public walkways; or
b. Near soffit vents or crawl space vents or other areas where condensate or vapor could create a nusiance or hazard or property damage; or
c. Where condensate vapor could cause damage or could be detrimental to the operation of regulators, relief valves, or other equipment.
2. When locating vent terminations, consideration must be given to prevailing winds, location, and other conditions which may cause recirculation of the combustiob products of adjacent vents.
Recirculation can cause poor combustion, inlet condensate problems, and accelerated corrosion of the heat exchangers.

A
X
B
V
V
V
V
X
X
AIR SUPPLY INLET
VVENT TERMINAL AREA WHERE TERMINAL IS NOT PERMITED
A
B
B
B
B
B
C
DE
FJ
I
L
HM
K
G
25--24--65--2
N
V
O
Other than Direct Vent Termination Clearance
Figure 8
V
V
14 440 01 1021 01
Item Clearance Descriptions Canadian Installation (1) U.S. Installation (2)
AClearance above grade, veranda, porch, deck, balcony, or
anticipated snow level 12²(30cm) # 12²(30 cm)
BClearance to a window or door that may be opened 6²(15 cm) for appliances £10,000 BTUH (3kW), 12²(30
cm) for appliances > 10,000 Btuh (3 kW) and £100,000 Btuh
(30 kW), 36²(91 cm) for appliances > 100,000 Btuh (30 kW)
4¢(1.2 m) below or to the side of the opening. 1¢(30 cm)
above the opening.
CClearance to a permanently closed window * *
DVertical clearance to a ventilated soffit located above the
terminal within a horizontal distance of 2¢(61cm) from the
centerline of the terminal
* *
EClearance to an unventilated soffit * *
FClearance to an outside corner * *
GClearance to an inside corner * *
HClearance to each side of the centerline extended above
electrical meter or gas service regulator assembly 3¢(91 cm) within 15¢(4.5 m) above the meter/regulator assembly 3¢(91 cm) within 15¢(4.5 m) above the meter/regulator assembly
IClearance to service regulator vent outlet 3¢(91 cm) *
JClearance to non--mechanical air supply inlet to building or
the combustion air inlet to any other appliance 6²(15 cm) for appliances £10,000 BTUH (3kW), 12²(30 cm) for appliances > 10,000 Btuh (3 kW) and £100,000 Btuh
(30 kW), 36²(91 cm) for appliances > 100,000 Btuh (30 kW)
4¢(1.2 m) below or to the side of opening: 1¢(30 cm) above
opening.
KClearance to a mechanical air supply inlet 6¢(1.83 m) 3¢(91 cm) above if within 10¢(3m) horizontally
LClearance under a veranda, porch, deck, or balcony 12²(30 cm) + *
MClearance to each side of the centerline extended above or
below vent terminal of the furnace to a dryer or water heater
vent, or other appliance’s direct vent intake or exhaust.
* *
NClearance from a plumbing vent stack 3¢(91 cm) 3¢(91 cm)
OClearance above a paved sidewalk or paved driveway located
on public property. 7¢(2.13 m) 7¢(2.13 m)
(1.) In accordance with the current CSA B149.1, Natural Gas and Propane Installation Code
(2.) In accordance with the current ANSI Z223.1/NFPA 54, National Fuel Gas Code
#18²(46 cm) above roof surface
+ Permitted only if veranda, porch, deck, or balcony is fully open on a minimum of two sides beneath the floor.
*For clearances not specified in ANSI Z223.1/NFPA 54 or CSA B149.1, clearances shall be in accordance with local installation codes and the requirements of the gas supplier and the manufacture’s
installation instructions.
** A vent shall not terminate directly above a sidewalk or paved driveway that is located between two single family dwellings and serves both dwellings.
Notes:
1. The vent for this appliance shall not terminate
a. Over public walkways; or
b. Near soffit vents or crawl space vents or other areas where condensate or vapor could create a nusiance or hazard or property damage; or
c. Where condensate vapor could cause damage or could be detrimental to the operation of regulators, relief valves, or other equipment.
2. When locating vent terminations, consideration must be given to prevailing winds, location, and other conditions which may cause recirculation of the combustiob products of adjacent vents.
Recirculation can cause poor combustion, inlet condensate problems, and accelerated corrosion of the heat exchangers.

15
440 01 1021 01
Condensate Drain Trap
Thisfurnaceremovesbothsensibleandlatentheatfromtheprod-
ucts of combustion. Removal of the latent heat results in con-
densationofthewatervapor.Thecondensateisremovedfromthe
furnacethroughthedrainsin the plastic transition and the ventfit-
ting. The drains connect to the externally mounted condensate
drain trap on the left or right side of the furnace.
The startup of a new furnace will involve a cycle or two of the fur-
nace to properly prime the condensate trap with water. Until the
trap is fully primed, some condensate will be pulledinto the com-
bustionblower.Thefurnacemaycycleonthepressureswitchcon-
nected to the plastic transition box due to condensate buildup.
Afterthetrapisprimed,thecondensatewillstartdrainingfromthe
furnace. The combustion blower will clear outany remaining con-
densateintheblowerhousingthroughtheventfittingdownstream
oftheblower.Notethatthecondensatetrapcanalsobeprimedby
pouring water into the 1/2²drain hose. Remove the1/2²ID drain
hosefromeitherthegutterorthewhitePVCTeeTrap.Usingafun-
nelpoureight(8)ouncesofwaterinto1/2²IDdrain hose.Waterwill
flow through the drain hose and into the condensate drain trap.
Thiswillprimeboththeventandthetransitionsidesofthetrap.Re-
connectthe1/2²IDdrainhosetotheoriginalcomponent,eitherthe
gutter or the PVC Tee Trap.
The condensate drain trap supplied with the furnace MUST be
used. The drain connection on the condensate drain trap is sized
for3/4²PVCorCPVCpipe,howeveralternate1/2²CPVC(nominal
5/8²O.D.) or vinyl tubing with a minimum inner diameter (I.D.) of
5/8²may also be used,as allowed by localcodes. Alternate drain
pipes and hoses may be used as allowed by local codes.
Thedrainlinemustmaintaina1/4²perfootdownwardslopetoward
thedrain.1/4²perfootisrecommended.Installationofanoverflow
line is recommended when the 1/4²per foot slope to the conden-
satedraincannotbemaintained.SeeFigure 18forproperrouting
and installation of the overflow.
DO NOT trap the drain line in any other location than at the con-
densate drain trap supplied with the furnace.
FROZEN AND BURST WATER PIPE HAZARD
Failure to do so may result in burst water pipes,
serious property damage.
If a condensate pump is installed, a plugged
condensate drain or a failed pump may cause the
furnace to shut down. Do not leave the home
unattended during freezing weather without turning
off water supply and draining water pipes or
otherwiseprotectingagainsttheriskoffrozenpipes.
!C
A
UTION
If possible, DO NOT route the drain line where it may freeze. The
drain line must terminate at an inside drain to prevent freezing of
the condensate and possible property damage.
1. A condensate sump pump MUST be used if required by lo-
cal codes, or if no indoor floor drain is available. The con-
densate pump must be approved for use with acidic
condensate.
2. A plugged condensate drain line or a failed condensate
pumpwillallowcondensatetospill.Ifthefurnaceisinstalled
where a condensate spill could cause damage, it is recom-
mended that an auxiliary safety switch be installed to pre-
ventoperationoftheequipmentintheeventofpumpfailure
or plugged drain line. If used, an auxiliary safety switch
should be installed in the R circuit (low voltage) ONLY.
3. If the auxiliary switch in the condensate pump is used, the
furnacemayshutdownduetoablockedcondensatelineor
failedpump.To prevent frozenwaterpipesseethe“Frozen
Water Pipe Hazard” section on Page 4 of this manual.
Condensate Drain Trap Freeze Protection
SpecialprecautionsMUST bemadeifinstallingfurnaceinanarea
which may drop below freezing. This can cause improper opera-
tion or damage to the equipment. If the the furnace environment
has the potential of freezing, the drain trapand drain line must be
protected.Use3to6wattperfootat115volt,40°Fself--regulating
shielded and waterproof heat tape. Wrap the drain trap and drain
line with the heat tape and secure with the ties. Follow the heat
tape manufacturer’s recommendations.

16 440 01 1021 01
INLET
EXHAUST
IN
ON
OFF
VENT
AIR FLOW
Figure 9 Upflow Installations Top Vent
Street Elbow
1/2²
²²
²CPVC
(Loose parts bag)
Casing Grommet
Black Rubber
5/8²
²²
²ID
(Loose parts bag)
DrainTee
Drain Connector Black PVC
3/4²
²²
²PVC X 1/2²
²²
²CPVC
(Loose parts bag)
Drain Line Vent Tee 3/4²
²²
²PVC or
1/2²
²²
²CPVC (Field supplied)
Drain Tube
Black Rubber
1/2²
²²
²ID&Clamps
Drain Tube
Corrugated 5/8²
²²
²ID
&Clamps
Relief Tube
Black Rubber
3/16²
²²
²ID
Coupling & Clamps
(Optional)
25--24--80
Single Pressure Switch
Dual Pressure Switch Detail
Drain Tube Black Rubber 5/8²
²²
²ID&Clamps,
Cut length to fit (Loose parts bag)
On Some Models
ONLY
Plastic Caps (2)
Yellow or black
Vent Drain
&Clamps
Upflow Installations Top Vent (See Figure 9)
RemoveplugfromthesideofthefurnacecasingwhereDrainTube
will exit.
Install casing grommet (black rubber 5/8²ID grommet -- in loose
parts bag)
Install the 1/2²CPVC street elbow on discharge of Trap
Install the black PVC tube connector (3/4²PVC x 1/2²CPVC from
loose parts bag) as shown in the illustration above.
Cut the black Drain Tube (5/8²ID -- in loose parts bag) to length to
fit between Trap and tube connector through grommet.
Clamp both ends of the Drain Tube using clamps provided.
GluetheCPVCstreetelbowtotheTrapusingappropriatecleaner
and solvent cement.
Connect the Tee trap and the main drain line exiting the casingas
shown Figure 18.
Note: It is recommended that all PVC piping and fitting connec-
tionsbefitupandinspectedbeforefinalcementing.Trapmustbe
primed before operation. Verify all condensate drain connec-
tions are securely clamped. A coupling and clamps (in loose part
bag)maybeinstalledasshownforfutureservicingoftheventsys-
tem.
NOTE: “PVC” is used as a generic term. Pipe and fitting materials used must be acceptable to the local code officials having
jurisdiction.

17
440 01 1021 01
INLET
EXHAUST
IN
ON
OFF
VENT
Figure 10 Upflow Installations Vent thru Left Side
Casing Grommet
Black Rubber
5/8²
²²
²ID
(Loose parts bag)
Drain Connector Black PVC
3/4²
²²
²PVC X 1/2²
²²
²CPVC
(Loose parts bag)
Drain Line Vent Tee 3/4²
²²
²PVC or 1/2²
²²
²CPVC (Field supplied)
Drain Tube
Black Rubber
1/2²
²²
²ID&Clamps
3/16²
²²
²ID Rubber Tube
Coupling & Clamps
(Optional)
25--24--81
Single Pressure
Switch
Dual Pressure Switch Detail
Tee Trap White PVC
(loose parts bag)
2²
²²
²PVC Coupling
On Some Models
ONLY
Plastic Cap
Yellow or black
Vent Drain
&Clamps
Rotate downward
5°
°°
°to 10°
°°
°
NOTE: Built--in channel will
be angled 5°to 10°also.
SIDE VIEW
Either: The PVC
Drain Tee or a field
supplied 2²
²²
²PVC Tee
AIR FLOWAIR FLOW
Drain Tube
Corrugated
5/8²
²²
²ID&Clamps
Upflow Installations Vent thru Left Side (See Figure 10)
Remove Drain Tee from inducer discharge and remove black
Drain Tube (1/2²ID) from bottom of Drain Tee. (*9MPD models
only)
Install Vent Pipe grommet in side of casing.
Cut an appropriate length of 2²PVC pipe long enough to exit the
cabinet and connect the vent drain to either:
·A standard field supplied 2²PVC tee (N9MP1 models), or
·A2²PVC coupling fastened onto the Drain Tee (*9MPD mod-
els)
Install Tee trap into bottom of tee.
Install the 1/2²CPVC street elbow on discharge of Trap
Install the black PVC drain connector (3/4²PVC x 1/2²CPVC from
loose parts bag) as shown in the illustration above.
Cut the black Drain Tube (5/8²ID -- in loose parts bag) to length to
fit between Trap and tube connector through grommet.
Clamp both ends of the Drain Tube using clamps provided.
GluetheCPVCstreetelbowtotheTrapusingappropriatecleaner
and solvent cement.
Connect the Tee trap and the main drain line exiting the casingas
shown in Figure 18.
Note: It is recommended that all PVC piping and fitting connec-
tions be fit up and inspected before final cementing. Both the in-
ternal Trap and the external Tee Trap must be primed before
operation. Verify all condensate drain connections are securely
clamped. A coupling and clamps (in loose part bag) may be
installed as shown for future servicing of the vent system.

18 440 01 1021 01
EXHAUST
AIR FLOW
INLET
IN
ON
OFF
VENT
Figure 11 All Models Vent thru Right Side
Casing Grommet
Black Rubber 5/8²
²²
²CPVC
(Loose parts bag)
Drain Connector Black PVC
3/4²
²²
²PVC X 1/2²
²²
²CPVC
(Loose parts bag)
Drain Line Vent Tee 3/4²
²²
²PVC
or 1/2²
²²
²CPVC (Field supplied)
Drain Tube
Corrugated
5/8²
²²
²ID&Clamps
Relief Tube
Black Rubber
3/16²
²²
²ID
25--24--82
Single Pressure Switch Detail
Dual
Pressure Switch
Tee Trap White PVC
(loose parts bag)
2²
²²
²PVC
Coupling
Barbed Coupling, 1/2²
²²
²OD
(loose parts bag)
Elbows Tubes (2) & Clamps Black,
1/2²
²²
²ID (loose parts bag)
Rotate downward
5°
°°
°to 10°
°°
°
NOTE: Built--in channel will
be angled 5°to 10°also.
SIDE VIEW
Plastic Cap
Yellow or black
Vent Drain
&Clamps
On Some Models
ONLY
Either: The PVC
Drain Tee or a field
supplied 2²
²²
²PVC Tee
All Models Vent thru Right Side (See Figure 11)
Disconnect the black Drain Tube between the drain vent and the
Trap.
Rotate the inducer 180°for a right side vent after loosening the4
inducer attachment screws. Reinstall and retighten the inducer
screws to 20²pounds torque.
Using the 1/2²OD barbed coupling in the loose parts bag connect
togetherwiththe2short1/2²IDelbowtubesandconnectthelower
dischargeportoftheventdraintotheTrap. Secureallconnections
with clamps.
Install the vent pipe grommet into the casing
Cut an appropriate length of 2²PVC pipe long enough to exit the
cabinet and connect the vent drain to either:
·A standard field supplied 2²PVC tee (*9MP1 models), or
·A2²PVC coupling fastened onto the Drain Tee (*9MPD
models)
Install Tee Trap into bottom section of Tee.
RemoveplugfromthesideofthefurnacecasingwhereDrainTube
will exit.
Install casing grommet (black rubber 5/8²ID grommet -- in loose
parts bag)
Install the 1/2²CPVC street elbow on discharge of Trap
Install the black PVC tube connector (3/4²PVC x 1/2²CPVC from
loose parts bag) as shown in the illustration above
Cut the black Drain Tube (5/8²ID -- in loose parts bag) to length to
fit between Trap and tube connector through grommet.
Clamp both ends of the Drain Tube using clamps provided.
GluetheCPVCstreetelbowtotheTrapusingappropriatecleaner
and solvent cement.
Connect the Tee trap and the main drain line exiting the casingas
shown in Figure 18.
Note: It is recommended that all PVC piping and fitting connec-
tions be fit up and inspected before final cementing. Both the in-
ternal Trap and the external Tee Trap must be primed before
operation. Verify all condensate drain connections are securely
clamped. A coupling and clamps (in loose part bag) may be
installed as shown for future servicing of the vent system.

19
440 01 1021 01
AIR FLOW
IN
ON
OFF
VENT
Drain Tube
Black Rubber
1/2²
²²
²ID&Clamps
Yellow or black Plastic Cap
Vent Drain
&Clamps
AIR FLOW
Figure 12 Downflow Left Side Vent and Trap
Relief Tube
Black Rubber 3/16²
²²
²ID
25--24--83
Single Pressure Switch Detail
Dual Pressure Switch
Tee Trap White PVC
(loose parts bag)
Flexible Tubing Connector,
3/16²
²²
²OD (loose parts bag)
Elbow Tube
Black Rubber
1/2²
²²
²ID&Clamps
(Loose Parts Bag)
EXHAUST
Cut Here
Drain Tube Corrugated 5/8²
²²
²ID
Cut at straight section
Leave room for clamp
WARNING
Move Caps
to top of
trap
Relief Tube Extension
Black Rubber,
3/16²
²²
²ID Cut to fit
(loose parts bag)
INLET
On Some Models
ONLY
Either: The PVC
Drain Tee or a field
supplied 2²
²²
²PVC Tee
Rotate downward
5°
°°
°to 10°
°°
°
NOTE: Built--in channel will
be angled 5°to 10°also.
SIDE VIEW
Coupling & Clamps
(Optional)
Trap Connection “Clamp ears”
PointedOUT
Preassemble&
insert into furnace
2²
²²
²PVC Coupling
Barbed Coupling 1/2²
²²
²OD
(Loose Parts Bag)
Downflow Left Side Vent and Trap (See Figure 12)
Remove the inducer mounting screws, rotate the inducer 180°
and retighten the inducer screws to 20²pounds torque.
Disconnect the hoses from the Trap assembly, and remove Trap
and Trap mounting bracket from the blower compartment. Using
cover plate and gasket provided in the loose parts bag, cover the
holefromtheburnercompartmenttotheblowercompartmentand
secure with screws.
MovethecapstothetopoftheTrapandmounttheTrapexternally
to the left side of the unit using the 2 screws provided.
Cutthe5/8²IDcorrugatedhoseasshownaboveandfastenthe90°
bend end to the Trap and fasten the straight end to the transition
drain. Secure both connections with clamps.
Reconnect the 1/2²ID drain hose from the vent drain to the Trap
andsecurewithaclamp.. Insomecases,additionallength willbe
required for this hose. Use the Black plastic 1/2²OD barbed cou-
plingandasuitablesectionof1/2²IDhosetomaketheconnection.
Secure all connections with clamps
Connect the 3/16²ID relief tube fromthe small port on the Trap to
the top port of the transition as shown in the picture. In some
cases,additionalhoselengthwillbeneeded. Usetheclearplastic
3/16²OD flexible tubing connector and a suitable length of extra
3/16²ID hose to make this connection.
Install the vent pipe grommet into the casing
Cut an appropriate length of 2²PVCpipe long , enough to exit the
cabinet and connect the vent drain to either:
·A standard field supplied 2²PVC tee (N9MP1), or
·A2²PVC coupling fastened onto the Drain Tee (*9MPD
models)
Install Tee Trap into bottom section of Tee.
Connect the Tee trap and the main drain line exiting the casingas
shown in Figure 18.
Note: It is recommended that all PVC piping and fitting connec-
tions be fit up and inspected before final cementing. Both the ex-
ternal Trap and the external Tee Trap must be primed before
operation. Verify all condensate drain connections are securely
clamped. A coupling and clamps (in loose part bag) may be
installed as shown for future servicing of the vent system.

20 440 01 1021 01
AIR FLOW
AIR FLOW
IN
ON
OFF
VENT
Figure 13 Downflow Right Side Vent and Trap
Drain Connector Black
PVC 3/4²
²²
²PVC X 1/2²
²²
²CPVC
(Loose parts bag)
Trap Connection “Clampears”
PointedOUT
Preassemble&
insert into furnace
25--24--83a
Single Pressure Switch Detail Dual Pressure Switch
Tee Trap White PVC
(loose parts bag)
Drain Tube Corrugated
5/8²
²²
²ID&Clamps
WARNING
Move Caps to top of trap
Drain Tube Black Rubber,
5/8²
²²
²ID Cut to fit & Clamps
(loose parts bag)
Barbed Coupling
1/2²
²²
²OD
(Loose Parts Bag) Drain Tube
Black Rubber
1/2²
²²
²ID
Cut to Fit &
Clamps
Either: The PVC
Drain Tee or a field
supplied 2²
²²
²PVC Tee
Rotate downward
5°
°°
°to 10°
°°
°
NOTE: Built--in channel will
be angled 5°to 10°also.
SIDE VIEW
Plastic Cap
Yellow or black
Vent Drain
&Clamps
INLET
On Some
Models ONLY 2²
²²
²PVC Coupling
Coupling & Clamps
(Optional)
Elbow Tube Black Rubber
1/2²
²²
²ID&Clamps
(Loose Parts Bag)
Relief Tube
Black Rubber 3/16²
²²
²ID
Downflow Right Side Vent and Trap (See Figure 13)
Remove the Drain Tee if installed.
Disconnect the hoses from the Trap assembly, and remove Trap
and Trap mounting bracket from the blower compartment. Using
cover plate and gasket provided in the loose parts bag, cover the
holefromtheburnercompartmenttotheblowercompartmentand
secure with screws.
MovethecapstothetopoftheTrapandmounttheTrapexternally
to the right side of the unit using the 2 screws provided.
Connect the corrugated Drain Tube from the transition box to the
Trapasshown. Ifanextensionisrequired,usetheblackPVCtube
connectorandtheblack5/8²IDDrainTubeintheloosepartsbag.
Cut tube to length. Secure all connections with clamps.
Connect the drain hose from the Vent Drain to the Trap. If an ex-
tension is required, use the black 1/2²OD barbed coupling, con-
nect a black 1/2²ID elbow tube and a suitable section of a 1/2²ID
drain tubeto make connection fromthe vent drain to the trap. Se-
cure all connections with clamps.
Install the vent pipe grommet into the casing
Cut an appropriate length of 2²PVCpipe long , enough to exit the
cabinet and connect the vent drain to either:
·A standard field supplied 2²PVCtee(N9MP1models),or
·A2²PVC coupling fastened onto the Drain Tee (*9MPD
models)
Install Tee Trap into bottom section of Tee.
Connect the Tee trap and the main drain line exiting the casingas
shown in Figure 18.
Note: It is recommended that all PVC piping and fitting connec-
tions be fit up and inspected before final cementing. Both the ex-
ternal Trap and the external Tee Trap must be primed before
operation. Verify all condensate drain connections are securely
clamped. A coupling and clamps (in loose part bag) may be
installed as shown for future servicing of the vent system.