Daikin DM96SE User manual

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5151 San Felipe St., Suite 500, Houston, TX 77056
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I NSTALLATION I NSTRUCTIONS FOR
DM96SE
S
INGLE -S TAGE G AS F URNACE
IOD-2013A
06/2018
(Type FSPCATEGORY IV Direct
or Non Direct VentAir Furnace)
These furnaces comply with requirements em-
bodied in theAmerican National Standard / Na-
tional Standard of CanadaANSI Z21.47·CSA-2.3
Gas Fired Central Furnaces.
Installer:
Affix all manuals
adjacent to the unit.
As a professional installer you have an obligation to know
theproductbetterthanthecustomer.Thisincludesallsafety
precautions and related items.
Prior to actual installation, thoroughly familiarize yourself
with this Instruction Manual. Pay special attention to all
safety warnings. Often during installation or repair it is
possible to place yourself in a position which is more
hazardous than when the unit is in operation.
Remember, it is your responsibility to install the product
safely and to know it well enough to be able to instruct a
customer in its safe use.
Safety is a matter of common sense...a matter of thinking
before acting. Most dealers have a list of specific good
safety practices...follow them.
Theprecautionslistedinthis Installation Manual areintended
as supplemental to existing practices. However, if there is
adirect conflict betweenexisting practicesandthe content
ofthismanual, the precautions listed here takeprecedence.
RECOGNIZE THIS SYMBOL
AS A SAFETY PRECAUTION.
O NLY PERSONNEL THAT HAVE BEEN TRAINED TO INSTALL , ADJUST , SERVICE OR
REPAIR ( HEREINAFTER , “ SERVICE ”) THE EQUIPMENT SPECIFIED IN THIS MANUAL
SHOULD SERVICE THE EQUIPMENT . T HE MANUFACTURER WILL NOT BE RESPONSIBLE
FOR ANY INJURY OR PROPERTY DAMAGE ARISING FROM IMPROPER SERVICE OR
SERVICE PROCEDURES . I F YOU SERVICE THIS UNIT , YOU ASSUME RESPONSIBILITY
FOR ANY INJURY OR PROPERTY DAMAGE WHICH MAY RESULT . I N ADDITION , IN
JURISDICTIONS THAT REQUIRE ONE OR MORE LICENSES TO SERVICE THE EQUIPMENT
SPECIFIED IN THIS MANUAL , ONLY LICENSED PERSONNEL SHOULD SERVICE THE
EQUIPMENT . I MPROPER INSTALLATION , ADJUSTMENT , SERVICING OR REPAIR OF
THE EQUIPMENT SPECIFIED IN THIS MANUAL , OR ATTEMPTING TO INSTALL , ADJUST ,
SERVICE OR REPAIR THE EQUIPMENT SPECIFIED IN THIS MANUAL WITHOUT PROPER
TRAINING MAY RESULT IN PRODUCT DAMAGE , PROPERTY DAMAGE , PERSONAL
INJURY OR DEATH .
TABLE OF CONTENTS
SAFETY CONSIDERATIONS ............................................. 2
SHIPPING INSPECTION .............................................. 4
ELECTROSTATIC DISCHARGE (ESD) PRECAUTIONS ...................... 4
TOTHE INSTALLER ............................................... 5
PRODUCT APPLICATION ............................................... 5
LOCATION REQUIREMENTS & CONSIDERATIONS ........................... 5
CLEARANCES AND ACCESSIBILITY ..................................... 6
EXISTING FURNACE REMOVAL ....................................... 7
THERMOSTAT LOCATION ............................................ 7
COMBUSTION & VENTILATION AIR REQUIREMENTS ........................ 7
INSTALLATION POSITIONS .............................................. 8
HORIZONTAL APPLICATIONS & CONSIDERATIONS .......................... 8
FURNACE SUSPENSION ............................................. 8
FRONT COVER PRESSURE SWITCH TUBE LOCATION .................... 8
DRAIN TRAP AND LINES ............................................ 8
LEVELING ........................................................ 8
ALTERNATE ELECTRICAL AND GAS LINE CONNECTIONS ................. 9
DRAIN PAN ....................................................... 9
FREEZE PROTECTION ............................................. 9
VENT/FLUE PIPE & COMBUSTION AIR PIPE .......................... 9
DUAL CERTIFICATION: NON-DIRECT/DIRECT VENT ................. 9
MATERIALS AND JOINING METHODS ................................ 9
PROPER VENT/FLUE AND COMBUSTION AIR PIPING PRACTICES .....10
TERMINATION LOCATIONS ........................................10
STANDARD FURNACE CONNECTIONS ...............................11
VENT/INTAKE TERMINATIONS
FOR INSTALLATION OF MULTIPLE DIRECT VENT FURNACES ..........16
CONCENTRIC VENT TERMINATION ...................................16
SIDE WALL VENT KIT ............................................16
INSTALLATION INSTRUCTIONS

2
S AFETY C ONSIDERATIONS
IMPORTANT NOTE: This unit is designed to meet the NOX
requirement of 14Ng/J maximum as required by the South
CoastAir Quality Management District and the San Joaquin
Valley Air Pollution Control District, both in the State of
California,and is intended for installation in those dis-
tricts only.
This unit has a Control System that compensates for cer-
tain installation and environmental conditions. This unit
must:
• Be properly installed, operated, and maintained
per the instructions.
• Be serviced only by properly trained Service
Technicians.
This unit is not approved for use with gasses other than
Natural Gas.
CONDENSATE DRAIN LINES & DRAIN TRAP ..........................16
GENERAL DRAIN INFORMATION ...................................17
FIELD SUPPLIED DRAIN ..........................................17
UPFLOW MODEL INSTALLED VERTICALLY ..........................17
DRAIN EXITING RIGHT SIDE ......................................17
DRAIN EXITING LEFT SIDE .......................................18
UPFLOW MODEL INSTALLED HORIZONTALLY WITH RIGHT SIDE DOWN 18
UPFLOW MODEL INSTALLED HORIZONTALLY WITH LEFT SIDE DOWN .19
UPFLOW MODEL INSTALLED HORIZONTALLY
WITH LEFT SIDE DOWN - ALTERNATE .........................19
ELECTRICAL CONNECTIONS .........................................20
WIRING HARNESS ...............................................20
115 VOLT LINE CONNECTIONS ..................................20
JUNCTION BOX RELOCATION ....................................20
24 VOLT THERMOSTAT WIRING .................................21
SINGLE-STAGE HEATING THERMOSTAT APPLICATION ...............21
FOSSIL FUEL APPLICATIONS ......................................21
GAS SUPPLY AND PIPING ...........................................21
GAS PIPING CONNECTIONS ......................................22
CIRCULATING AIR & FILTERS .......................................23
DUCT WORK - AIR FLOW ........................................23
CHECKING DUCT STATIC .........................................24
BOTTOM RETURN AIR OPENING [UPFLOW MODELS] ..............24
FILTERS - READ THIS SECTION
BEFORE INSTALLING THE RETURN AIR DUCT WORK .............25
UPRIGHT INSTALLATIONS.........................................25
HORIZONTAL INSTALLATIONS .....................................26
DRAIN TRAP PRIMING ...........................................26
FURNACE OPERATION............................................26
GAS SUPPLY PRESSURE MEASUREMENT ...........................26
GAS MANIFOLD PRESSURE MEASUREMENT AND ADJUSTMENT .......27
GAS INPUT RATE MEASUREMENT (NATURAL GAS ONLY)...........28
TEMPERATURE RISE .............................................28
CIRCULATOR BLOWER SPEEDS ....................................28
BLOWER HEAT OFF DELAY TIMINGS ..............................29
NORMAL SEQUENCE OF OPERATION .................................29
POWER UP.....................................................29
HEATING MODE .................................................29
COOLING MODE ................................................29
FAN ONLY MODE ...............................................29
OPERATIONAL CHECKS..............................................30
SAFETY CIRCUIT DESCRIPTION ......................................30
INTEGRATED CONTROL MODULE ..................................30
PRIMARY LIMIT .................................................30
AUXILIARY LIMIT ................................................30
BURNER TEMPERATURE SWITCH ..................................30
PRESSURE SWITCHES.............................................30
FLAME SENSOR .................................................30
TROUBLESHOOTING ................................................30
ELECTROSTATIC DISCHARGE (ESD) PRECAUTIONS..................30
RESETTING FROM LOCKOUT .....................................31
MAINTENANCE .....................................................31
ANNUAL INSPECTION ............................................31
FILTERS ........................................................31
30BURNERS .......................................................32
INDUCED DRAFT AND CIRCULATOR BLOWERS ......................32
CONDENSATE TRAP AND DRAIN SYSTEM (QUALIFIED SERVICER ONLY)32
FLAME SENSOR (QUALIFIED SERVICER ONLY) ......................32
FLUE PASSAGES (QUALIFIED SERVICER ONLY) ......................32
BEFORE LEAVING AN INSTALLATION ..................................32
REPAIR AND REPLACEMENT PARTS ...................................32
DIAGNOSTIC CHART ................................................33
AIRFLOW
DM96SE ......................................................34
WIRING DIAGRAM
DM96SE ......................................................35
Units that are not installed, maintained, or operated prop-
erly may result in “noisy” operation during the Heating
Cycle. If this unit is making unusual or objectionable noises
during the Heating Cycle, turn the heat off at the thermo-
stat and contact a qualified Service organization right
away.
Adhere to the following warnings and cautions when install-
ing, adjusting, altering, servicing, or operating the furnace.
To ensure proper installation and operation, thoroughly read
this manual for specifics pertaining to the installation and
application of this product.
This furnace is manufactured for use with natural gas.

3
Install this furnace only in a location and position as speci-
fied in LOCATION REQUIREMENTS & CONSIDERATIONS sec-
tion and INSTALLATION POSITIONS section of this manual.
Provide adequate combustion and ventilation air to the
furnace as specified in COMBUSTION & VENTILATION AIR
REQUIREMENTS section of this manual.
Combustion products must be discharged to the outdoors.
Connect this furnace to an approved vent system only, as
specified in VENT/FLUE PIPE & COMBUSTION AIR PIPE
section of this manual.
Never test for gas leaks with an open flame. Use a com-
mercially available soap solution made specifically for the
detection of leaks to check all connections, as specified
in GAS SUPPLY AND PIPING section of this manual.
Always install a furnace to operate within the furnace’s
intended temperature-rise range with a duct system which
has external static pressure within the allowable range,
as specified on the furnace rating plate and OPERATIONAL
CHECKS section of these instructions.
When a furnace is installed so that supply ducts carry air
circulated by the furnace to areas outside the space con-
taining the furnace, the return air shall also be handled
by duct(s) sealed to the furnace casing and terminating
outside the space containing the furnace.
A gas-fired furnace for installation in a residential garage
must be installed as specified in the LOCATION REQUIRE-
MENTS AND CONSIDERATIONS section of this manual.
This furnace cannot be used as a construction site heater.
FROZEN ANDBURST WATER PIPE HAZARD
F
AILURE TO PROTECT AGAINST THE RISK OF FREEZING MAY RESULT IN
PROPERTY DAMAGE .
S
PECIAL PRECAUTIONS MUST BE MADE IF INSTALLING FURNACE IN AN
AREA WHICH MAY DROP BELOW FREEZING . T HIS CAN CAUSE IMPROPER
OPERATION OR DAMAGE TO EQUIPMENT . I F THE FURNACE
ENVIRONMENT HAS THE POTENTIAL OF FREEZING , THE DRAIN TRAP AND
DRAIN LINE MUST BE PROTECTED . T HE USE OF ACCESSORY DRAIN TRAP
HEATERS , ELECTRIC HEAT TAPE AND / OR RV ANTIFREEZE IS
RECOMMENDED FOR THESE INSTALLATIONS .
CAUTION
T O PREVENT PERSONAL INJURY OR DEATH DUE TO IMPROPER
INSTALLATION , ADJUSTMENT , ALTERATION , SERVICE OR MAINTENANCE ,
REFER TO THIS MANUAL . F OR ADDITIONAL ASSISTANCE OR
INFORMATION , CONSULT A QUALIFIED INSTALLER , SERVICER AGENCY OR
THE GAS SUPPLIER .
WARNING
I F THE INFORMATION IN THESE INSTRUCTIONS IS NOT FOLLOWED
EXACTLY , A FIRE OR EXPLOSION MAY RESULT CAUSING PROPERTY
DAMAGE
, PERSONAL INJURY OR LOSS OF LIFE .
D O NOT STORE OR USE GASOLINE OR OTHER FLAMMABLE VAPORS AND
LIQUIDS IN THE VICINITY OF THIS OR ANY OTHER APPLIANCE .
D
O NOT TRY TO LIGHT ANY APPLIANCE .
D
O NOT TOUCH ANY ELECTRICAL SWITCH ; DO NOT USE ANY PHONE
IN YOUR BUILDING .
I
MMEDIATELY CALL YOUR GAS SUPPLIER FROM A NEIGHBOR ’ S
PHONE . F OLLOW THE GAS SUPPLIER ’ S INSTRUCTIONS .
I
F YOU CANNOT REACH YOUR GAS SUPPLIER , CALL THE FIRE
DEPARTMENT .
I
NSTALLATION AND SERVICE MUST BE PERFORMED BY A QUALIFIED
INSTALLER , SERVICE AGENCY OR THE GAS SUPPLIER .
WHAT TO DO IF YOU SMELL GAS:




WARNING
T HIS PRODUCT CONTAINS OR PRODUCES A CHEMICAL OR CHEMICALS
WHICH MAY CAUSE SERIOUS ILLNESS OR DEATH AND WHICH ARE
KNOWN TO THE S TATE OF C ALIFORNIA TO CAUSE CANCER , BIRTH
DEFECTS OR OTHER REPRODUCTIVE HARM .
WARNING
H EATING UNIT SHOULD NOT BE UTILIZED WITHOUT REASONABLE ,
ROUTINE , INSPECTION , MAINTENANCE AND SUPERVISION . I F THE
BUILDING IN WHICH ANY SUCH DEVICE IS LOCATED WILL BE VACANT ,
CARE SHOULD BE TAKEN THAT SUCH DEVICE IS ROUTINELY INSPECTED ,
MAINTAINED AND MONITORED . IN THE EVENT THAT THE BUILDING
MAYBE EXPOSED TO FREEZING TEMPERATURES AND WILL BE VACANT ,
ALL WATER - BEARING PIPES SHOULD BE DRAINED , THE BUILDING SHOULD
BE PROPERLY WINTERIZED , AND THE WATER SOURCE CLOSED . IN THE
EVENT THAT THE BUILDING MAY BE EXPOSED TO FREEZING
TEMPERATURES AND WILL BE VACANT , ANY HYDRONIC COIL UNITS
SHOULD BE DRAINED AS WELL AND , IN SUCH CASE , ALTERNATIVE HEAT
SOURCES SHOULD BE UTILIZED .
WARNING
T O PREVENT POSSIBLE PROPERTY DAMAGE , PERSONAL INJURY OR
DEATH DUE TO ELECTRICAL SHOCK , THE FURNACE MUST BE LOCATED TO
PROTECT THE ELECTRICAL COMPONENTS FROM WATER .
WARNING
Drain trap must be primed at time of installation. Trap is
internallypartitioned; add waterto bothinletportsuntil wa-
ter appears at both sides of the outlet opening. Failure to
prime trap at time of installation may have a negative ef-
fect on combustion quality and pressure switch action.

4
P OSSIBLE PROPERTY DAMAGE , PERSONAL INJURY OR DEATH DUE TO
FIRE , EXPLOSION , SMOKE , SOOT , CONDENSATION , ELECTRICAL SHOCK
OR CARBON MONOXIDE MAY RESULT FROM IMPROPER INSTALLATION ,
REPAIR OPERATION , OR MAINTENANCE OF THIS PRODUCT .
WARNING
S HOULD OVERHEATING OCCUR OR THE GAS SUPPLY FAIL TO SHUT OFF ,
TURN OFF THE MANUAL GAS SHUTOFF VALVE EXTERNAL TO THE
FURNACE BEFORE TURNING OFF THE ELECTRICAL SUPPLY .
WARNING
electrostatic potential, these steps will help avoid exposing
the integrated control module to electrostatic discharge.
This procedure is applicable to both installed and non-in-
stalled (ungrounded) furnaces.
1. Disconnect all power to the furnace. Do not touch the
integratedcontrol moduleoranywireconnectedtothe
control prior to discharging your body’s electrostatic
chargetoground.
2. Firmly touch a clean, unpainted, metal surface of the
furnaces near the control. Any tools held in a person’s
handduringgroundingwillbedischarged.
3. Serviceintegratedcontrolmodule orconnectingwiring
following the discharge process in step 2. Use caution
not to recharge your body with static electricity; (i.e.,
do not move or shuffle your feet, do not touch
ungroundedobjects,etc.). If youcomeincontact with
an ungrounded object, repeat step 2 before touching
controlor wires.
4. Discharge your body to ground before removing a new
control from its container. Follow steps 1 through 3 if
installing the control on a furnace. Return any old or
new controls to their containers before touching any
ungroundedobject.
B10259-216
CO can cause serious illness including permanent brain
damage or death.
Advertencia especial para la instalaciónde calentadoresó manejadoras
de aire en áreas cerradas como estacionamientos ó cuartos de servicio.
B10259-216
El monóxido de carbono puede causar enfermedades severas
como daño cerebral permanente ó muerte.
Las emisiones de monóxido de carbono pueden circular a través
del aparato cuando se opera en cualquier modo.
B10259-216
RISQUED'EMPOISONNEMENT AUMONOXYDE DE CARBONE
Le monoxyde de
des carbone peut causer des maladies graves telles que dommages permanents au cerveau et meme la mort.
Cette ventilation est nécessaire pour éviter le danger d'intoxication
au CO pouvant survenir si un appareil produisant du monoxyde
de carbone continue de fonctionner au sein de la zone confinée.
SHIPPING INSPECTION
All units are securely packed in shipping containers tested
according to International Safe Transit Association specifica-
tions. The carton must be checked upon arrival for external
damage. If damage is found, a request for inspection by
carrier’s agent must be made in writing immediately.
The furnace must be carefully inspected on arrival for damage
andbolts orscrewswhichmayhavecomelooseintransit. Inthe
event of damage the consignee should:
1. Makeanotationondeliveryreceipt ofanyvisibledamage
toshipmentorcontainer.
2. Notifycarrierpromptlyand requestaninspection.
3. Withconcealeddamage,carrier mustbenotifiedassoon
as possible - preferably within five days.
4. Filetheclaimwiththefollowingsupportdocumentswithin
a nine month statute of limitations.
• Original or certified copy of the Bill of Lading, or
indemnitybond.
• Originalpaidfreightbillorindemnityinlieuthereof.
• Originalorcertified copyoftheinvoice, showingtrade
andotherdiscounts or reductions.
• Copy of the inspection report issued by carrier’s
representativeatthetimedamageisreportedtocarrier.
Thecarrieris responsibleformakingpromptinspection ofdam-
ageandforathoroughinvestigationofeachclaim. Thedistribu-
torormanufacturerwillnotacceptclaimsfromdealersfortrans-
portationdamage.
ELECTROSTATIC DISCHARGE (ESD) PRECAUTIONS
NOTE: Dischargeyour body’sstaticelectricity before touching
unit. An electrostatic discharge can adversely affect electrical
components.
Usethefollowingprecautionsduringfurnaceinstallationandser-
vicingtoprotecttheintegratedcontrolmodulefromdamage. By
putting the furnace, the control, and the person at the same

5
TOTHE INSTALLER
Before installing this unit, please read this manual thoroughly
to familiarize yourself with specific items which must be ad-
hered to, including but not limited to: unit maximum external
static pressure, gas pressures, BTU input rating, proper elec-
trical connections, circulating air temperature rise, minimum
or maximum CFM, and motor speed connections.
T O PREVENT PROPERTY DAMAGE , PERSONAL INJURY OR DEATH DUE TO
FIRE , DO NOT INSTALL THIS FURNACE IN A MOBILE HOME , TRAILER , OR
RECREATIONAL VEHICLE .
WARNING
P RODUCT A PPLICATION
This furnace is primarily designed for residential home-heat-
ing applications. It is NOT designed or certified for use in
mobile homes, trailers or recreational vehicles. Neither is it
designed or certified for outdoor applications. The furnace
must be installed indoors (i.e., attic space, crawl space, or
garage area provided the garage area is enclosed with an
operating door).
This furnace can be used in the following non-industrial com-
mercial applications:
Schools, Office buildings, Churches, Retail stores,
Nursing homes, Hotels/motels, Common or office areas
In such applications, the furnace must be installed with the
following stipulations:
• It must be installed per the installation instructions
provided and per local and national codes.
• It must be installed indoors in a building constructed
on site.
• It must be part of a ducted system and not used in a
free air delivery application.
• It must not be used as a “make-up” air unit.
• It must be installed as a two-pipe systems for
combustion air.
• All other warranty exclusions and restrictions apply
This furnace is an ETL certified appliance and is
appropriate for use with natural gas.
Dual certification means that the combustion air inlet pipe is
optional and the furnace can be vented as a:
Non-directvent (singlepipe)centralforcedairfurnace
in which combustion air is taken from the installation
area or from air ducted from the outside or,
Direct vent (dual pipe) central forced air furnace in
which all combustion air supplied directly to the
furnace burners through a special air intake system
outlined in these instructions.
This furnace cannot be used as a construction site heater.
To ensure proper furnace operation, install, operate and
maintain the furnace in accordance with these installation
and operation instructions, all local building codes and or-
dinances. In their absence, follow the latest edition of the
National Fuel Gas Code (NFPA 54/ANSI Z223.1), Installation
Codes, local plumbing or waste water codes, and other appli-
cable codes.
A copy of the National Fuel Gas Code (NFPA 54/ANSI Z223.1)
can be obtained from any of the following:
American National Standards Institute
23 West 43rd Street, 4th Floor
New York, NY 10036
National Fire Protection Association
1 Batterymarch Park
Quincy, MA 02169-7471
CSA International
8501 East Pleasant Valley
Independence, OH 441311
The rated heating capacity of the furnace should be greater
than or equal to the total heat loss of the area to be heated.
Thetotalheatlossshouldbecalculatedbyanapprovedmethod
or in accordance with “ASHRAE Guide” or “Manual J-Load
Calculations” published by the Air Conditioning Contractors of
America.
L OCATION R EQUIREMENTS &C ONSIDERATIONS
Follow the instructions listed below and the guidelines pro-
vided in the Combustion and VentilationAir Requirements sec-
tion when selecting a furnace location.
T O PREVENT POSSIBLE EQUIPMENT DAMAGE , PROPERTY DAMAGE ,
PERSONAL INJURY OR DEATH , THE FOLLOWING BULLET POINTS MUST BE
OBSERVED WHEN INSTALLING THIS UNIT .
WARNING
P OSSIBLE PROPERTY DAMAGE , PERSONAL INJURY OR DEATH DUE TO
FIRE , EXPLOSION , SMOKE , SOOT , CONDENSATION , ELECTRICAL SHOCK
OR CARBON MONOXIDE MAY RESULT FROM IMPROPER INSTALLATION ,
REPAIR OPERATION , OR MAINTENANCE OF THIS PRODUCT .
WARNING
• Centrally locate the furnace with respect to the
proposed or existing air distribution system.
• Ensure the temperature of the return air entering
the furnace is between 55°F and 100°F when the
furnace is heating.
• Provide provisions for venting combustion products
outdoors through a proper venting system. Special
considerationshould begiventovent/fluepiperouting
andcombustion airintakepipewhenapplicable. Refer
toVent/FluePipeandCombustionAirPipe-Termination
Locations for appropriate termination locations and

6
to determine if the piping system from furnace to
terminationcanbeaccomplishedwithintheguidelines
given. NOTE: The length of flue and/or combustion
air piping can be a limiting factor in the location of
the furnace.
• Locate the furnace so condensate flows downwards
to the drain. Do not locate the furnace or its
condensate drainage system in any area subject to
below freezing temperatures without proper freeze
protection. Refer to Condensate Drain Lines and Trap
for further details.
• Ensure adequate combustion air is available for the
furnace. Improper or insufficient combustion air can
exposebuildingoccupantstogascombustion products
that could include carbon monoxide. Refer to
Combustion and Ventilation Air Requirements.
• Set the furnace on a level floor to enable proper
condensate drainage. If the floor becomes wet or
damp at times, place the furnace above the floor on
a concrete base sized approximately 1-1/2" larger
than the base of the furnace. Refer to the Horizontal
Applications and Considerations for leveling of
horizontal furnaces.
• Ensure upflow or horizontal furnaces are not installed
directly on carpeting, or any other combustible
material. The only combustible material allowed is
wood.
• Exposure to contaminated combustion air will result
in safety and performance-related problems. Do not
install the furnace where the combustion air is
exposed to the following substances:
permanent wave solutions
chlorinatedwaxes orcleaners chlorine-based
carbontetrachloride water softeningchemicals
swimmingpool chemicals
deicingsalts or chemicals halogen typerefrigerants
printing inks cleaning solutions (such as
perchloroethylene)
paint removers varnishes
hydrochloricacid cementsand glues antistaticfabric
softenersforclothes dryers
masonry acid washing materials
• Sealoffanon-directventfurnace if it is installed near
an area frequently contaminated by any of the above
substances. Thisprotectsthe non-directventfurnace
from airborne contaminants. To ensure that the
enclosednon-directventfurnacehasanadequatesupply
ofcombustion air,ventfromanearbyuncontaminated
room or from outdoors. Refer to the Combustion and
VentilationAirRequirementsfordetails.
• If the furnace is used in connection with a cooling coil
unit,installthefurnaceupstreamorinparallelwiththe
coolingcoilunit. Prematureheatexchangerfailurewill
resultifthecoolingunitisplacedaheadofthefurnace.
For vertical (upflow or downflow) applications, the
minimum cooling coil width shall not be less than
furnace width minus 1”. Additionally, a coil
installed above an upflow furnace may be the
same width as the furnace or may be one size
larger than the furnace. Example: a “C” width
coil may be installed with a “B” width furnace.
For upflow applications, the front of the coil and
furnace must face the same direction.
• If the furnace is installed in a residential garage,
position the furnace so that the burners and ignition
source are located not less than 18 inches (457 mm)
above the floor. Protect the furnace from physical
damage by vehicles.
• If the furnace is installed horizontally, ensure the
access doors are not on the “up/top” or “down/
bottom” side of the furnace.
• Do not connect this furnace to a chimney flue that
serves a separate appliance designed to burn solid
fuel.
CLEARANCES AND ACCESSIBILITY
NOTES:
• For servicing or cleaning, a 24” front clearance
is required.
• Unit connections (electrical, flue and drain) may
necessitate greater clearances than the
minimum clearances listed above.
• In all cases, accessibility clearance must take
precedence over clearances from the enclosure
where accessibility clearances are greater.
POSITION* SIDES REAR FRONT BOTTOM FLUE TOP
Upflow 0" 0" 3" C 0" 1"
Horizontal 6" 0" 3" C 0" 6"
C = If placed on combustible floor, floor MUST be wood only.
DM96SE MINIMUM CLEARANCES TOCOMBUSTIBLE MATERIALS
(INCHES)
Installations must adhere to the clearances to combustible
materials to which this furnace has been design certified.
The minimum clearance information for this furnace is pro-
vided on the unit’s clearance label. These clearances must be
permanently maintained. Clearances must also accommo-
date an installation’s gas, electrical, and drain trap and drain
line connections. If the alternate combustion air intake or
vent/flue connections are used additional clearance must be
provided to accommodate these connections. Refer to Vent/
Flue Pipe and Combustion Air Pipe for details.
NOTE: In addition to the required clearances to combustible
materials, a minimum of 24 inches service clearance must be
availablein front of theunit.
A furnace installed in a confined space (i.e., a closet or utility
room)must havetwoventilation openingswithatotalminimum
free area of 0.25 square inches per 1,000 BTU/hr of furnace
inputrating.RefertoSpecificationSheetapplicabletoyourmodel
for minimum clearances to combustible surfaces. One of the

7
ventilation openings must be within 12 inches of the top; the
other opening must be within 12 inches of the bottom of the
confined space. In a typical construction, the clearance be-
tween the door and door frame is usually adequate to satisfy
this ventilation requirement.
TOP
BOTTOM
TOP
BOTTOM
Figure 1
EXISTING FURNACE REMOVAL
NOTE: When an existing furnace is removed from a venting
systemservingother appliances,theventingsystemmaybetoo
largetoproperlyventtheremainingattachedappliances.
ThefollowingventtestingprocedureisreproducedfromtheAmeri-
can National Standard/National Standard of Canada for Gas-
Fired Central Furnaces ANSI Z21.47, CSA-2.3 latest edition
Section 1.23.1.
The following steps shall be followed with each appliance connected to the
venting system placed in operation, while any other appliances connected
to the venting system are not in operation:
1. Seal any unused openings in the venting system.
2. Inspect the venting system for proper size and hori-
zontal pitch, as required by the National Fuel Gas
Code,ANSI Z223.1 instructions. Determine that there
is no blockage or restriction, leakage, corrosion and
other deficiencies which could cause an unsafe con-
dition.
3. As far as practical, close all building doors and win-
dows and all doors between the space in which the
appliance(s) connected to the venting system are lo-
cated and other spaces of the building.
4. Close fireplace dampers.
5. Turn on clothes dryers andany appliance not connected
to the venting system. Turn on any exhaust fans, such
as range hoods and bathroom exhausts, so they shall
operate at maximum speed. Do not operate a summer
exhaust fan.
6. Follow the lighting instructions. Place the appliance
being inspected in operation.Adjust thermostat so ap-
pliance shall operate continuously.
7. Test for spillage fromdraft hood appliancesat the draft
hood relief opening after 5 minutes of main burner
operation. Use the flame of a match or candle.
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.
9. After it has been determined that each appliance
connected to the venting system properly vents when
tested as outlined above, return doors, windows,
exhaust fans, fireplace dampers and any other gas
burning appliance to their previous conditions of use.
If resizing is required on any portion of the venting system,
use the appropriate table in Appendix G in the latest edition
of the National Fuel Gas Code ANSI Z223.1.
THERMOSTAT LOCATION
The thermostat should be placed approximately five feet
from the floor on a vibration-free, inside wall in an area
having good air circulation. Do not install the thermostat
where it may be influenced by any of the following:
• Drafts,or deadspotsbehinddoors,incorners,orunder
cabinets.
• Hot or cold air from registers.
• Radiant heat from the sun.
• Light fixtures or other appliances.
• Radiantheatfromafireplace.
• Concealedhotorcoldwaterpipes,orchimneys.
• Unconditioned areas behind the thermostat, such as
anoutsidewall.
Consulttheinstructionspackagedwith the thermostat for
mountinginstructionsandfurtherprecautions.
C OMBUSTION & V ENTILATION A IR R EQUIREMENTS
T O AVOID PROPERTY DAMAGE , PERSONAL INJURY OR DEATH ,
SUFFICIENT FRESH AIR FOR PROPER COMBUSTION AND VENTILATION OF
FLUE GASES MUST BE SUPPLIED . M OST HOMES REQUIRE OUTSIDE AIR BE
SUPPLIED INTO THE FURNACE AREA .
WARNING
Improvedconstructionandadditionalinsulationinbuildingshave
reducedheatloss byreducingairinfiltration andescapearound
doors and windows. These changes have helped in reducing
heating/cooling costs but have created a problem supplying
combustionandventilationairforgasfiredandotherfuelburning
appliances. Appliances that pull air out of the house (clothes
dryers,exhaustfans,fireplaces,etc.)increasetheproblemby
starving appliances for air.
House depressurization can cause back drafting or improper
combustionofgas-firedappliances,thereby exposing building
occupants to gas combustion products that could include car-
bonmonoxide.
If this furnace is to be installed in the same space with other
gas appliances, such as a water heater, ensure there is an ad-
equate supply of combustion and ventilation air for the other
appliances. Refer to the latesteditionoftheNationalFuelGas
CodeNFPA54/ANSIZ223.1orCAN/CSAB149.1-15 Installation

8
Codes or applicable provisions of the local building codes for
determiningthecombustionairrequirementsfortheappliances.
Most homes will require outside air be supplied to the fur-
nace area by means of ventilation grilles or ducts connect-
ing directly to the outdoors or spaces open to the outdoors
such as attics or crawl spaces.
I NSTALLATION P OSITIONS
This furnace may be installed in an upright position or hori-
zontal on either the left or right side panel. Do not install
this furnace on its back. For upright upflow furnaces, return
air ductwork may be attached to the side panel(s) and/or
basepan. For horizontal upflow furnaces, return air duct-
work must be attached to the basepan. For both upright or
horizontal furnaces, return ductwork must be attached to
the basepan (top end of the blower compartment). NOTE:
Ductwork must never be attached to the back of the fur-
nace. Contact your distributor for proper airflow require-
ments and number of required ductwork connections. Refer
to “Recommended Installation Positions” figure for appro-
priate installation positions, ductwork connections, and re-
sulting airflow arrangements.
Figure 2A
Figure 2B
Figure 2C
Recommended Installation Positions
H ORIZONTAL A PPLICATIONS &C ONSIDERATIONS
When installing a furnace horizontally, additional consider-
ation must be given to the following:
FURNACE SUSPENSION
If suspending the furnace from rafters or joists, use 3/8"
threaded rod and 2”x2”x1/8” angle iron as shown in the fol-
lowing diagram. The length of rod will depend on the applica-
tion and the clearances necessary.
If the furnace is installed in a crawl space it must be sus-
pended from the floor joist or supported by a concrete pad.
Never install the furnace on the ground or allow it to be ex-
posed to water.
2" 2" 3/8" ANGLE IRON
(3 PLACES )
XX
Figure 3
FRONT COVER PRESSURE SWITCH TUBE LOCATION
When a furnace is installed horizontally with left side down,
the front cover pressure switch tube must be re-located to
the lower port of the collector box cover.
1. Remove tube from front cover pressure switch and
collector box cover.
2. Remove rubber plug from bottom collector box port
and install on top collector box port.
3. Locate 24” x 1/4” tube in the bag assembly.
4. Install one end on front cover pressure switch.
5. Route tube to lower port on collector box cover and
cut off excess tubing.
DRAIN TRAP AND LINES
Inhorizontalapplicationsthecondensatedraintrapissecuredto
thefurnacesidepanel,suspendingitbelowthefurnace. Amini-
mum clearanceof 5.5” below thefurnacemustbe provided for
the drain trap. Additionally, the appropriate downward piping
slopemust be maintained from the draintrap to thedrain loca-
tion. Refer to Condensate Drain Trap and Lines for further de-
tails.Ifthedraintrapanddrainlinewill beexposedtotempera-
turesnearorbelowfreezing,adequate measuresmustbetaken
topreventcondensate fromfreezing.

9
LEVELING
Leveling ensures proper condensate drainage from the heat
exchanger. For proper flue pipe drainage, the furnace must
be level lengthwise from end to end. The furnace should
have a slight tilt from back to front with the access doors
downhill from the back panel approximately 1/2 to 3/4
inches. The slight tilt allows the heat exchanger condensate,
generated in the recuperator coil, to flow forward to the
recuperator coil front cover.
ALTERNATE ELECTRICAL AND GAS LINE CONNECTIONS
This furnace has provisions allowing for electrical and gas
line connections through either side panel. In horizontal ap-
plications the connections can be made either through the
“top” or “bottom” of the furnace.
DRAIN PAN
A drain pan must be provided if the furnace is installed above
a conditioned area. The drain pan must cover the entire area
underthefurnace(andairconditioning coilifapplicable).
FREEZE PROTECTION
Refer toHorizontalApplicationsandConditions-DrainTrapand
Lines.
V ENT /F LUE P IPE & C OMBUSTION A IR P IPE
This manual will refer to the pipe that discharges products
to the outdoors as the “vent” pipe or “flue” pipe. The pipe
that supplies air for combustion to the furnace will be
referred to as the “intake” pipe or “combustion air” pipe. A
condensing gas furnace achieves its high level of efficiency by
extracting almost all of the heat from the products of combus-
tion and cooling them to the point where condensation takes
place. Because of the relatively low flue gas temperature and
watercondensationrequirements,PVCorABS are typically used
as venting and intake pipe materials In CanadaABS is not an
approved vent pipe material, but it is permissible to use as
combustion air pipe material.
In addition to PVC and ABS pipe and fittings, Innoflue®by
Centrotherm Eco Systems and PolyPro®by M&G Duravent are
also approved vent and combustion air materials for instal-
lations in the U.S.A. and Canada. Manufacturers Installation
instructionsfor these products must be followed.These prod-
ucts have specific instructions for installing, joining and ter-
minating. Do not mix materials or components of one manu-
facturer with materials or components of another manufac-
turer.
All furnaces are manufactured with 2" vent / intake pipe and
connectors. For furnaces requiring installation of 3" pipe,
the transition from 2" to 3" should be done as close to the
furnace as practically possible.
This furnace must not be connected to Type B, BW, or L vent or
vent connector, and must not be vented into any portion of a
factorybuiltormasonrychimneyexceptwhenusedasapathway
for PVC as described later in this section. Never common vent
this appliance with another appliance or use a vent which is
used by a solid fuel appliance. Do not use commercially avail-
able “no hub connectors” other than those shipped with this
product.
It is the responsibility of the installer to follow the manufac-
turers’ recommendations and to verify that all vent/flue pip-
ing and connectors are compatible with furnace flue products.
Additionally, it is the responsibility of the installer to ensure
that all piping and connections possess adequate structural
integrity and support to prevent flue pipe separation, shift-
ing, or sagging during furnace operation.
WARNING
P OSSIBLE PROPERTY DAMAGE , PERSONAL INJURY OR DEATH MAY
OCCUR IF THE CORRECT CONVERSION KITS ARE NOT INSTALLED . T HE
APPROPRIATE KITS MUST BE APPLIED TO ENSURE SAFE AND PROPER
FURNACE OPERATION . A LL CONVERSIONS MUST BE PERFORMED BY A
QUALIFIED INSTALLER OR SERVICE AGENCY .
Manifold
Pressure
High
Stage
Natural 0-4500' None 3.0" WC None
Pressure
Switch
Change
Gas Altitude Kit
U PON COMPLETION OF THE FURNACE INSTALLATION , CAREFULLY
INSPECT THE ENTIRE FLUE SYSTEM BOTH INSIDE AND OUTSIDE OF THE
FURNACE TO ASSURE IT IS PROPERLY SEALED . L EAKS IN THE FLUE
SYSTEM CAN RESULT IN SERIOUS PERSONAL INJURY OR DEATH DUE TO
EXPOSURE TO FLUE PRODUCTS , INCLUDING CARBON MONOXIDE .
WARNING
F AILURE TO FOLLOW THESE INSTRUCTIONS CAN RESULT IN BODILY
INJURY OR DEATH . C AREFULLY READ AND FOLLOW ALL INSTRUCTIONS
GIVEN IN THIS SECTION .
WARNING
DUAL CERTIFICATION: NON-DIRECT/DIRECT VENT
This furnace is dual certified and may be installed as a non-
direct vent (single pipe) or direct vent (dual pipe) appliance.
A non-direct vent installation requires only a vent/flue pipe,
while a direct vent installation requires both a vent/flue pipe
and a combustion air intake pipe. Refer to the appropriate
section for details concerning piping size, length, number of
elbows, furnace connections, and terminations.

10
T O AVOID BODILY INJURY , FIRE OR EXPLOSION , SOLVENT CEMENTS
MUST BE KEPT AWAY FROM ALL IGNITION SOURCES ( I . E ., SPARKS , OPEN
FLAMES , AND EXCESSIVE HEAT ) AS THEY ARE COMBUSTIBLE LIQUIDS .
A
VOID BREATHING CEMENT VAPORS OR CONTACT WITH SKIN AND / OR
EYES .
WARNING
PREFERRED
Figure 4
TRANSITION NO LESS
THAN 45 DEGREES TO
HORIZONTAL PLANE TO
AVOID CREATING A WATER
TRAP IN VENT PIPING.
ACCEPTABLE
Figure 5
NO TRANSITION ON
HORIZONTAL PLANE,
THIS CREATES A
WATER TRAP AND
RESTRICTS FLUE
GASES
Figure 6
Some models require the use of 3” pipe. Do not transition
from a 2” to 3” pipe in a horizontal section of pipe as this
may create a water trap.
Piping must be adequately secured and supported to prohibit
sagging,joint separation,and/ordetachment fromthefurnace.
Horizontalrunsofvent/fluepipingmustbesupportedeverythree
to five feet and must maintain a 1/4 inch per foot downward
slope,backtowards thefurnace,toproperly returncondensate
to the furnace’s drain system. Allowances should be made for
minorexpansionandcontractionduetotemperature variations.
T O AVOID BODILY INJURY , FIRE OR EXPLOSION , SOLVENT CEMENTS
MUST BE KEPT AWAY FROM ALL IGNITION SOURCES ( I . E ., SPARKS , OPEN
FLAMES , AND EXCESSIVE HEAT ) AS THEY ARE COMBUSTIBLE LIQUIDS .
A
VOID BREATHING CEMENT VAPORS OR CONTACT WITH SKIN AND / OR
EYES .
WARNING
MATERIALS AND JOINING METHODS
Two-three-inch nominal diameter PVC Schedule 40 pipe
meeting ASTM D1785, PVC primer meeting ASTM F656,
and PVC solvent cement meeting ASTM D2564 specifica-
tions must be used. Fittings must be DWV type fittings
meeting ASTM D2665 and ASTM D3311. Carefully follow
the manufacturer’s instructions for cutting, cleaning, and
solvent cementing of PVC.
The use of Schedule 40 PVC cellular core DWV meeting
ASTM F891-1 or ABS cellular core (Foam Core) plastic
pipe is also acceptable as a flue/vent and intake pipe
material. PVC primer meeting ASTM F656 and PVC sol-
vent cement meeting ASTM D2564 specifications must be
used. Fittings must be DWV type fittings meeting ASTM
D2665 andASTM D3311. Carefully follow the manufactures
instructions for cutting, cleaning and solvent cementing
of PVC.
NOTE: Requirement does not apply to the combustion air
pipe.
As an alternative to PVC pipe, primer, solvent cement, and
fittings, ABS materials which are in compliance with the fol-
lowing specifications may be used. Two-or-three-inch ABS
Schedule 40 pipe must meet ASTM D1527. Solvent cement
for ABS to ABS joints must meet ASTM D2235. The solvent
cement for the PVC to ABS transition joint must meet ASTM
D3138. Fittings must be DWV type fittings meeting ASTM
D2661 and ASTM D3311. Carefully follow the manufacturers’
instructions for cutting, cleaning, and solvent cementing PVC
and/or ABS.
All 90° elbows must be medium radius (1/4 bend DWV) or
long radius (Long sweep 1/4 bend DWV) types conforming to
ASTM D3311. A medium radius (1/4 bend DWV) elbow mea-
sures 3 1/16” minimum from the plane of one opening to the
center line of the other opening for 2” diameter pipe, and 4
9/16” minimum for 3” pipe.
PROPER VENT/FLUE AND COMBUSTION AIR PIPING PRACTICES
Adhere to these instructions to ensure safe and proper fur-
nace performance. The length, diameter, and number of el-
bows of the vent/flue pipe and combustion air pipe (when
applicable) affects the performance of the furnace and must
be carefully sized. All piping must be installed in accordance
with local codes and these instructions.

11
For this reason, particular care must be taken to secure pip-
ing when a long run is followed by a short offset of less than
40 inches.
Precautions shouldbe takentopreventcondensate from freez-
inginside thevent/fluepipeand/oratthevent/fluepipetermi-
nation. All vent/flue piping exposed to freezing temperatures
below35°Fforextendedperiodsof timemustbeinsulated with
1/2” thick closed cell foam. Also all vent/flue piping exposed
outdoors in excess of the terminations shown in this manual
(or in unheated areas) must be insulated with 1/2” thick
closed cell foam. Inspect piping for leaks prior to installing
insulation.
TERMINATION LOCATIONS
NOTE: Refer toLocationRequirements andConsiderationsfor
combustionaircontaminant restrictions.
12"
Non-Direct Vent
Vent/Flue Termination
No Terminations
Above Walkway
12"
min.
4'
min.
Non-Direct Vent
Vent/Flue Termination
Direct Vent
Vent/Flue Termination
<10'
Forced Air
Inlet
Non-Direct Vent
&
Direct Vent
Vent/Flue Terminations
Grade or Highest
Anticipated
Snow Level
3' min.
12" min.
4' min.
12" min.
Vent Termination Clearances
Figure 7
Thefollowingbulletsanddiagramdescribetherestrictionscon-
cerningtheappropriatelocation of vent/fluepipeandcombus-
tion air intake pipe (when applicable) terminations. Refer to
Non-DirectVent (SinglePipe)Pipingand Direct Vent(DualPipe)
Piping located in this section for specific details on termination
construction.
• All terminations (flue and/or intake) must be located
atleast12inchesabovegroundlevelortheanticipated
snowlevel.
• Vent terminations (non-direct and direct vent) must
terminate at least 3 feet above any forced air inlet
locatedwithin 10feet.
NOTE: This provision does not apply to the combustion
airintake termination of adirect ventapplication.
• Theventterminationofanon-directventapplicationmust
terminateatleast4feetbelow,4 feet horizontallyfrom,
or 1 foot above any door, window, or gravity air inlet
into any building.
• The vent termination of a direct vent application must
terminate at least 12 inches from any opening through
which flue gases may enter a building (door, window, or
gravity air inlet).
• Thevent terminationofventpiperunverticallythrougha
roofmustterminateatleast12 inchesabovetheroofline
(or the anticipated snow level) and be at least 12 inches
from any vertical wall (including any anticipated snow
buildup).
• A vent termination shall not terminate over public
walkways
or over an area where condensate or vapor could create
a nuisance or hazard or could be detrimental to the
operation of regulators, relief valves, or other
equipment.
•The combustion air intake termination of a direct vent
application should not terminate in an area which is
frequently dusty or dirty.
STANDARD FURNACE CONNECTIONS
It is the responsibility of the installer to ensure that the pip-
ing connections to the furnace are secure, airtight, and ad-
equately supported.
Vent/Flue Pipe
The vent pipe outlet is sized to accept 2” pipe. Secure
vent/flue pipe directly into the furnace fitting with the
appropriate glue. Alternately, a small section of 2" pipe
may be glued in the furnace socket and a rubber coupling
installed to allow removal for future service. Combustion
Air and Vent piping should be routed in a manner to avoid
contact with refrigerant lines, metering devices, conden-
sate drain lines, etc. If necessary, clearances may be in-
creased by creating an offset using two 45 degree elbows.
This joint can be rotated on the fitting to establish maxi-
mum clearance between refrigerant lines, metering de-
vices, and condensate drain lines, etc. This joint is the
equivalent of one 90 deg. elbow when considering elbow
count. (Figure 8A)

12
45 DEGREE
ELBOWS
Increased Clearance Configuration
Figure 8A
NOTE: For non-direct vent installations, a minimum of
one 90° elbow should be installed on the combustion air
intake coupling to guard against inadvertent blockage.
E DGES OF SHEET METAL HOLES MAY BE SHARP . U SE GLOVES AS A
PRECAUTION WHEN REMOVING HOLE PLUGS .
WARNING
C OMBUSTION A IR P IPE
DIRECT VENT INSTALLATIONS
On upflow units secure the combustion air intake pipe to the
air intake coupling by using a take apart rubber coupling
supplied with the furnace or a plastic coupling. Also, the
intake coupling may be inverted to allow the intake pipe
to be glued directly to it. After inverting the coupling,
secure it to the furnace top with screws.
VENT-DRAIN
The RF000142 Coupling
Figure 8B
COMBUSTIONAIR INTAKE OPTIONS: The RF000142 coupling
canbe secured directlyto thefurnaceintakecoupling if con-
densation is a concern. If the RF000142 is used on the com-
bustion air inlet, it must be installed with the arrow pointing
up. It should be noted, the combustion air will actually be
moving in a direction opposite of the arrow on the RF000142
coupling. It must have a field supplied, trapped drain tube
free-draining to proper condensate disposal location. Aloop
in the drain tube can serve as a trap. The unused RF000142
drain fitting should be capped. (Figure 8B)Atee installed in
the intake pipe is also an acceptable method of catching
condensation. It must have a field supplied, trapped drain
tube or pipe, free-draining to proper condensate disposal
location. Aloop in the drain tube can serve as a trap.
Insert flange. Cut 2 ½”long . RF000142
2 ½”
Figure 9
T HE RUBBER ELBOW IS NOT DESIGNED TO SUPPORT A LOAD . W HEN THE
RUBBER ELBOW IS MOUNTED EXTERNALLY TO THE FURNACE CABINET ,
EXTREME CARE MUST BE TAKEN TO ADEQUATELY SUPPORT FIELD -
SUPPLIED VENT / FLUE PIPING , AS DAMAGE CAN RESULT IN LEAKS
CAUSING BODILY INJURY OR DEATH DUE TO EXPOSURE TO FLUE GASES ,
INCLUDING CARBON MONOXIDE
WARNING
NON-DIRECTVENTINSTALLATIONS
Aminimum ofone90°elbowshouldbeinstalledonthecombus-
tion air intake “coupling” to guard against inadvertent block-
age.
ALTERNATE VENT/FLUE LOCATION
The alternate vent/flue location is the large hole directly in
line with the induced draft blower outlet. To use the alter-
nate vent/flue location refer to the following steps and the
Alternate Vent/Flue Location Figure 9.
NOTE: In the horizontal left installation position, a means
of condensate collection must be provided to keep vent
pipe condensate from entering the draft inducer housing.
If the vent drain elbow is eliminated from the installa-
tion, an RF000142 kit must be used.
1. Remove the four screws from the vent pipe flange on
top the furnace.

13
2. Remove the internal elbow and vent pipe
3. Cut 2 1/2" from the flange .
4. Remove plastic plug in line with the inducer outlet
5. Install cut end of the flanged section and connect
to inducer with rubber coupling supplied with
furnace.
6. Install screws removed in step 1 securing flange to
cabinet.
B E SURE NOT TO DAMAGE INTERNAL WIRING OR OTHER COMPONENTS
WHEN REINSTALLING COUPLING AND SCREWS .
WARNING
CUTHERE
Figure 10
Vent/Flue Pipe Cuts
ALTERNATE COMBUSTION AIR PROVISION
(Upflow / Horizontal models only)
When using the alternate venting location, either in a hori-
zontal left side down installation or a vertical installation
using down – venting, an alternate combustion air opening
can be used.Alocating dimple is located on the right side of
the furnace cabinet. The locating dimple is 1 7/8" mea-
sured from the front edge of the cabinet in line with the
knock out.To use the alternate combustion air location:
1. Remove screws and combustion air flange from
cabinet.
2. Insert cabinet plug in unused combustion air hole.
3. Drill a pilot hole at the cabinet dimple (size dictated
by knockout tool used).
4. Use a knockout tool to create a 3" diameter hole
5. Install combustion air flange and secure with screws
removed in step one.
NON-DIRECT VENT (SINGLE PIPE) PIPING
Non-directvent installations requireonlyavent/flue pipe. The
ventpipecanberunhorizontallywithanexitthroughthesideof
thebuildingorrunverticallywith anexitthroughtheroofofthe
building. The vent can also be run through an existing unused
chimney;however,itmustextendaminimumof12inchesabove
thetopofthechimney. Thespacebetweentheventpipeandthe
chimney must be closed with a weather-tight, corrosion-resis-
tant flashing.
Although non-direct vent installations do not require a com-
bustion air intake pipe, a minimum of one 90° elbow should
be attached to the furnace’s combustion air intake if: an up-
right installation uses the standard intake location, or a hori-
zontal installation uses the alternate air intake location. This
elbow will guard against inadvertent blockage of the air in-
take.
VENT/FLUE PIPE LENGTHS AND DIAMETERS
NOTE: If either a 90 degree or 45 degree elbow is used for
termination, it must be pointed downward.
Refer to the Direct and Non-Direct Vent Table for applicable
length,elbows,and pipediameterforconstruction ofthevent/
fluepipesystem ofanon-directvent installation. Inadditionto
the vent/flue pipe, a single 90° elbow should be secured to the
combustionair intaketopreventinadvertentblockage. Thetee
usedin thevent/flueterminationmustbeincludedwhendeter-
mining the number of elbows in the piping system.
Max Allowable Vent Length of Vent/Flue Pipe & Combustion
Air Pipe (Ft)
12345678
2 9590858075706560
3 103 96 89 82 75 68 61 54
2 9085807570656055
3 158 151 144 137 130 123 116 109
2 5550454035302520
3 151 144 137 130 123 116 109 102
*MES960403BN
*MES960603BN
*MES960805CN
MODEL Pipe Size (in) Number of Elbows
4500 ft altitude and above use 3” pipe
VENT/FLUE PIPE TERMINATIONS
NOTE: If either a 90 degree or 45 degree elbow is used for
termination, it must be pointed downward.
The vent/flue pipe may terminate vertically, as through a roof,
orhorizontally,asthrough anoutsidewall.
Vertical vent/flue pipe terminations should be as shown in
the following figure. Refer to Vent/Flue Pipe and Combustion
Air Pipe - Termination Locations for details concerning loca-

14
VENT/FLUE TEE (
or
45° ELBOW
TURNED DOWN or
90° ELBOW TURNED
DOWN
OPTIONAL)
12" MIN. ABOVE
HIGHESTANTICIPATED
SNOW LEVEL
12" MIN.
Horizontal Termination (Single Pipe)
Above Highest Anticipated Snow Level
Figure 14
Figure 13
STRAIGHT
ELBOWS
COMBUSTION AIR INTAKE
(OPTIONAL)
*Not required for
single pipe installation
TEE (OPTIONAL)
96”MAX.-3”MIN.
ROOFLINE
12” MIN
HEIGHT DIFFERENCE
BETWEEN
INTAKEAND VENT
12” MIN TO ROOF OR HIGHEST
ANTICIPATED SNOW LEVEL
Figure 12
Figure 11
Floor
Use alternate vent
& combination air locations
DOWN VENTING UPFLOW MODEL FURNACES ONLY
Basement/Crawlspace
Condensate trapped
to prevent flue gas from escaping
and routed to field supplied
condensate disposal
Combustion Air Pipe
Vent Pipe
All piping and fittings must be joined per material manufacturer’s specifications
to prevent separation and flue gas leaks.
Both Pipes Terminated
Outside Structure
1/4” per foot min. slope
6’ MAX.
Field Supplied
Drain Tee on Vent Pipe

15
tion restrictions. The penetration of the vent through the
roof must be sealed tight with proper flashing such as is used
with a plastic plumbing vent.
Horizontal vent/flue pipe terminations should be as shown in
the following figure. Refer to Vent/Flue Pipe and Combustion
Air Pipe. To secure the pipe passing through the wall and
prohibit damage to piping connections, a coupling should be
installed on either side of the wall and solvent cemented to a
length of pipe connecting the two couplings. The length of
pipe should be the wall thickness plus the depth of the socket
fittings to be installed on the inside and outside of the wall.
The wall penetration should be sealed with silicone caulk-
ing material.
NOTE: Terminate both pipes in the same pressure zone
(same side of roof, no major obstacles between pipes,
etc.).
DIRECT VENT (DUAL PIPE) PIPING
Direct vent installations require both a combustion air intake
and a vent/flue pipe. The pipes may be run horizontally and
exit through the side of the building or run vertically and exit
through the roof of the building. The pipes may be run through
an existing unused chimney; however, they must extend a
minimum of 12 inches above the top of the chimney. The
space between the pipes and the chimney must be closed with
a weather tight, corrosion resistant flashing. Both the com-
bustion air intake and a vent/flue pipe terminations must be
in the same atmospheric pressure zone. Refer to Vent/Flue
and Combustion Air Pipe - Termination Locations or Concen-
tric Vent Termination for specific details on termination con-
struction. For details concerning connection of pipes to the
furnace, refer to the Vent/Flue Pipe and Combustion Pipe -
Standard Furnace Connections or Alternate Furnace Connec-
tions.
90º OR 45°
ELBOW
12" MIN. TO GRADE OR
HIGHEST ANTICIPATED
SNOW LEVEL
6” MAX
10”- 24”
4” MIN
Standard Horizontal Terminations (Dual Pipe)
Figure 15
90°
ELBOWS
12" MIN. ABOVE
HIGHEST ANTICIPATED
SNOW LEVEL
3” - 24”
Alternate Horizontal Vent Termination (Dual Pipe)
Figure 16
VENT/FLUE & COMBUSTION AIR PIPE LENGTHS & DIAMETERS
Refer to the following table for applicable length, elbows, and
pipe diameter for construction of the vent/flue and combus-
tion air intake pipe systems of a direct vent (dual pipe) instal-
lation. The number of elbows tabulated represents the num-
ber of elbows and/or tees in each (Vent/Flue & Combustion
Air Intake) pipe. Elbows and/or tees used in the terminations
must be included when determining the number of elbows in
the piping systems.
If the combustion air intake pipe is to be installed above a
finished ceiling or other area where dripping of condensate
will be objectionable, insulation of the combustion air pipe
may be required.
Use 1/2” thick closed cell foam insulation such as
Armaflex™ or Insultube™ where required.
90°
ELBOWS
12" MIN. ABOVE
HIGHEST ANTICIPATED
SNOW LEVEL
3”-24” BETWEEN PIPES
Combustion Air Intake may also be snorkeled to obtain 12” min
ground clearance.
Alternate Vent Termination Above Anticipated Snow Level
(Dual Pipe)
Figure 17

16
VENT/FLUE AND COMBUSTION AIR PIPE TERMINATIONS
The vent/flue and combustion air pipes may terminate verti-
cally, as through a roof, or horizontally, as through an outside
wall.
Vertical pipe terminations should be as shown in the following
figure. Referto Vent/FluePipeandCombustionPipe-Termina-
tion Locations for details concerning location restrictions. The
penetrations through the roof must be sealed tight with proper
flashing such as is used with a plastic plumbing vent.
Vent & CombustionAir Intake Measurements for Standard
Horizontal Terminations (Dual Pipe)
Center to center = 10” min / 24” max.
Vertical separation: 0” - 24”
Vent termination from wall = 8” min / 12” max.
Combustion air intake from wall = 6” max.
Vent and intake clearance to ground or anticipated snow
level = 12” min.
3” MIN
12” MIN TO GRADE OR HIGHEST
ANTICIPATED SNOW LEVEL
3”MIN
24”MAX
12” MIN SEPARATION
Termination of Multiple Direct Vent Furnaces
Figure 18
VENT/INTAKE TERMINATIONS FOR INSTALLATION OF MULTIPLE
DIRECT VENT FURNACES
Ifmore than one directvent furnaceistobe installed vertically
throughacommonrooftop,maintainthesameminimumclear-
ances between the exhaust vent and air intake terminations of
adjacent units as with the exhaust vent and air intake termina-
tions of a single unit.
If more than one direct vent furnace is to be installed horizon-
tallythrougha commonsidewall,maintainthe clearancesasin
thefollowingfigure.Alwaysterminateallexhaustventoutletsat
the same elevation and always terminate all air intakes at the
same elevation.
CONCENTRIC VENT TERMINATION
Refer to the directions provided with the Concentric Vent Kit
(DCVK)forinstallationspecifications.
Vertical Installation
HorizontalInstallation
Side Wall Vent Kit
Figure 19
SIDE WALL VENT KIT
This kit is to be used with 2” or 3” direct vent systems. The
vent kit must terminate outside the structure and may be in-
stalledwith theintakeand exhaustpipeslocatedside-by-sideor
with onepipe abovetheother.These kits are NOT intendedfor
usewithsinglepipe(non-directvent) installations.
Refertothe directions furnished with theSideWall Vent Kit
(p/n 0170K00000S or 0170K00001S)for installation speci-
fications.
C ONDENSATE D RAIN L INES & D RAIN T RAP
Acondensinggasfurnace achieves its highlevelofefficiencyby
extracting heat from the products of combustion to the point
where condensationtakes place. The condensate must be col-
lected in the furnace drain trap and routed to an appropriate
drain location in compliance with local and national codes.
Followthe bulletslistedbelowwheninstallingthedrainsystem.
Refer to the following sections for specific details concerning
furnace drain trap installation and drain hose hook ups.
• Thedraintrapsuppliedwiththefurnacemustbe
used.
• The drain trap must be primed at time of
installation.
• Thedrainlinebetweenfurnaceanddrainlocation
mustmeet local and nation codes.
• The drain line between furnace and drain location
mustmaintain a 1/4inch perfootdownwardslope
towardthedrain.
• Donot trap the drainline inany otherlocation thanat
thedraintrapsuppliedwiththefurnace.
• If the drain line is routed through an area which may
seetemperaturesnearorbelowfreezing,precautions
must be taken to prevent condensate from freezing
within the drain line.

17
• If an air conditioning coil is installed with the
furnace, a common drain may be used. An open tee
must be installed in the drain line, near the cooling
coil, to relieve positive air pressure from the coil’s
plenum. This is necessary to prohibit any
interference with the function of the furnace’s drain
trap.
NOTE: In vertical installations, air conditioning coil condensate may
drain into the furnace trap as long as there is a trap between
the coil and the furnace trap and the drain pipe is not
terminating below the water level of the furnace trap.
#3
#1 #2
#4 #5
#6
#7 #8
#9
#10
#11
100 Degree
Elbow
Coupling
NOTE: Drain components shown for information purposes only.
Figure 20
GENERAL DRAIN INFORMATION
All furnace models come with a factory installed drain
trap. For vertical installations, the trap will remain in
the factory position. All furnace models installed hori-
zontally require the trap to be relocated. Many drain hoses
have a built–in grommet which will provide a cabinet seal
when installed. See instructions below for your model and
installation position. NOTE: Both sides of the drain trap
must be primed prior to initial furnace start up
FIELD SUPPLIED DRAIN
Drain the furnace and air conditioning coil if applicable, in
compliance with code requirements. In horizontal instal-
lations, a field installed rubber coupling will allow the
drain trap to be removed for cleaning. The drain trap must
be primed before initial furnace start up. When an air
conditioning coil drain is connected to the field supplied
furnace drain, it must be vented by an open tee installed
at a height no higher than the bottom of the furnace col-
lector box to prevent air conditioning condensate from
backing up into the furnace if the common drain was
blocked.
UPFLOW MODEL INSTALLED VERTICALLY
The trap and factory installed hoses remain as shipped.
The furnace drain may exit either the right or left side of
the furnace cabinet. Both sides of the cabinet have two
.875” diameter holes which can be used interchangeably
for drain and low voltage wiring purposes. If a higher drain
exit is needed, a .875” diameter hole may be added in the
area shown in Figure 21. Any unused cabinet opening
must be sealed. Do not allow drain hose to sag or trap
water.
Side Cut-Out
12”
3” Right side shown.
Acceptable
area for
drain hole.
Figure 21
DRAIN EXITING RIGHT SIDE
1. Locate and Install the 45º pipe / hose drain coupling
from the outside of the cabinet (barbed end goes in
thecabinet)throughhole in the rightsideofthecabinet
and secure with two field supplied #8 self-tapping
screws (see Figure 22).
2. Locate the long drain hose #3 and cut at line “A” .
3. Install large end of hose #3 to trap outlet and secure
with 1.25" clamp.
4. Install smaller end of hose #3 on 45º elbow and
secure with 1" clamp.
5. Refer to Field Supplied Drain section for instructions
on field supplied / installed drain on outlet of furnace
trap.

18
Hose #11 Hose #2
Figure 23
UPFLOW MODEL INSTALLED HORIZONTALLY WITH RIGHT SIDE
DOWN
Minimum 5 1/2" clearance is required for the drain trap be-
neath the furnace.
1. Remove the clamps from both ends of the drain hoses.
2. Remove the two screws holding the drain trap to the
blowerdeck.
3. Remove the trap and two hoses from the blower deck
4. Removethetwoplugsfromtherightsideofthecabinet
and install them in the blower deck.
5. (Draining the Vent Elbow ) Locate hose #2 (factory
installed) and cut 1” away from the 45 degree bend,
discard the 45 degree section. Insert hose #2 from
outside the cabinet through the cabinet drain hole
nearest the top, secure it to the barbed fitting in the
elbow with a red clamp.
6. (Draining the Collector Box) Install the non-grommet
endof hose #11 from outside thecabinet in thebottom
drain hole. Install on collector box and secure with a
silver clamp.
7. Use two silver clamps and secure the hoses to drain
trap. The trap outlet faces the front of the furnace.
Secure the trap to the cabinet using two screws
removed in step 2 by inserting the two screws through
the large set of holes in the top mounting tabs of the
trap into the two predrilled holes in the side of the
cabinet.
8. Refer to Field Supplied Drain section for instructions
on field supplied / installed drain on outlet of furnace
trap.
DRAIN EXITING LEFT SIDE
1. Install the 45 degree pipe / hose drain coupling from
the outside of the cabinet (barbed end goes in the
cabinet)throughthe hole in the leftside of the cabinet
and secure with two field supplied #8 self-tapping
screws (see Figure 22).
2. Locate the long drain hose #3 and cut at “B” line
for a 17.5" cabinet; cut at line “C” for a 21" cabinet;
do not cut for a “D” width cabinet.
3. Install large end of hose #3 to trap outlet and secure
with 1.25" clamp.
4. Install smaller end of hose #3 on 45º elbow and secure
with 1" clamp.
5. Refer to Field Supplied Drain section for instructions
on field supplied / installed drain on outlet of furnace
trap.
Hose #1
Hose #2
45 degree
barb-pipe
adapter
45 degree
barb-pipe
adapter
Installer selects right or left side drain
and installs this hose accordingly
Figure 22

19
13.Use two silver clamps and secure the hoses to drain
trap. The trap outlet faces the front of the furnace.
Secure the trap to the cabinet using two screws
removed in step 2 by inserting the two screws through
the large set of holes in the top mounting tabs of the
trap into the two predrilled holes in the side of the
cabinet.
14.Refer to Field Supplied Drain section for instructions
on field supplied / installed drain on outlet of furnace
trap.
Insert flange. Cut 2 ½” long . RF000142
2 ½”
Figure 25
UPFLOW MODEL INSTALLED HORIZONTALLY WITH LEFT SIDE
DOWN - ALTERNATE
*Also see Front Cover Pressure Switch Tube Location on
page 10.
1. (Draining the RF000142 Coupling) Locate hose #2
(factory installed). Cut off and discard the 45°radius
end.
2. Install 90°radius end of hose #2 on RF000142 drain
outlet and secure with a red clamp.
3. Insert couplinginhose#2 and secure witha redclamp.
4. Locate hose #5 and cut 3" from the non-grommet end.
Discard the section without the grommet.
5. Insertthe cut end of tube#5 throughthe lower cabinet
drain hole.
6. Insert 100 degree elbow in the cut end of hose #5.
7. Locate hose #6. Using red clamps, connect between
the coupling and 100 degree elbow, cutting off excess
tubing.
8. (Draining theCollectorBox)Remove cap from leftside
collector box drain port (bottom in horizontal left
position) and install it on right side (top) collector box
drain port.
Hose #6Hose #5 Hose #11
Figure 24
UPFLOW MODEL INSTALLED HORIZONTALLY WITH LEFT SIDE
DOWN
Minimum 5 1/2" clearance is required for the drain trap
beneath the furnace.
*Also see Front Cover Pressure Switch Tube Location on page
10.
1. Removethe clamps from thetwo draintubes onthe trap.
2. Remove the two screws holding the drain trap to the
blowerdeck.
3. Remove the trap and hoses from the blower deck .
4. Remove the two plugs from the left side of the cabinet
and install them in the blower deck.
5. (Draining the Vent Elbow) Locate hose #6. Measuring
from the non-grommet end; cut off and discard 1 ½” for
a “D” width cabinet, 5” for a “C” width cabinet, 8 ½”
for a “B” width cabinet.
6. Remove the rubber plug from vent – drain elbow side
port. Place hose #6 on the vent – drain elbow side port
and secure with a silver clamp .
7. Unused vent-drain elbow drip leg port must be sealed
to prevent flue gases from escaping. Insert the rubber
plug removed in step 6 into the unused elbow drain
port. Inserting a blunt tool such as a 3/16” Allen
wrench into the center of the rubber plug will stretch
the plug and allow complete insertion.
8. Locate hose #5 and cut 3” from the non-grommet end.
Discard the section without the grommet.
9. Insert the cut end of tube #5 through the lower cabinet
drain hole.
10.Connect hose #6 & hose #5 using 100º elbow and secure
with two red clamps
11.(Draining the Collector Box) Remove cap from left side
collectorboxdrain port (bottominhorizontalleftposition)
and install it on right side (top) collector box drain port.
12.Install the non-grommet end of hose #11 from outside
the cabinet in the upper drain hole. Install on collector
box and secure with a silver clamp.

20
9. Install the non-grommet end of hose #11 from
outside the cabinet in the upper drain hole. Install
on collector box and secure with a silver clamp.
10.Use two silver clamps and secure the hoses to drain
trap. The trap outlet faces the front of the furnace.
Secure the
trap to the cabinet using two screws removed in step
2 by inserting the two screws through the large set of
holes in
thetopmounting tabs ofthetrapintothe twopredrilled
holes in the side of the cabinet.
E LECTRICAL C ONNECTIONS
E DGES OF SHEET METAL HOLES MAY BE SHARP . U SE GLOVES AS A
PRECAUTION WHEN REMOVING HOLE PLUGS .
WARNING
T O PREVENT PERSONAL INJURY OR DEATH DUE TO ELECTRIC SHOCK ,
DISCONNECT ELECTRICAL POWER BEFORE INSTALLING OR SERVICING THIS
UNIT .
WARNING
HIGH VOLTAGE !
T O AVOID THE RISK OF INJURY , ELECTRICAL SHOCK OR
DEATH , THE FURNACE MUST BE ELECTRICALLY
GROUNDED IN ACCORDANCE WITH LOCAL CODES OR IN
THEIR ABSENCE , WITH THE LATEST EDITION OF THE
N
ATIONAL E LECTRIC C ODE .
WARNING
WIRING HARNESS
The wiring harness is an integral part of this furnace. Wires
arecolorcodedfor identification purposes. Refertothewiring
diagram for wire routings. If any of the original wire as sup-
plied with the furnace must be replaced, it must be replaced
with wiring material having a temperature rating of at least
105°C. Anyreplacementwiring must be a copper conductor.
115 VOLT LINE CONNECTIONS
Beforeproceedingwithelectrical connections, ensure thatthe
supplyvoltage,frequency, and phase correspondtothatspeci-
fiedontheunitratingplate. Powersupply to the furnace must
beNECClass 1,andmustcomplywith allapplicablecodes. The
furnacemustbeelectrically grounded in accordancewithlocal
codes or, in their absence, with the latest edition of The Na-
tional Electric Code, ANSI NFPA 70 .
Useaseparatefusedbranchelectricalcircuitcontainingprop-
erly sized wire, and fuse or circuit breaker. The fuse or
circuit breaker must be sized in accordance with the maxi-
mumovercurrentprotectionspecifiedonthe unit rating plate.
An electrical disconnect must be provided at the furnace
location.
Connect hot, neutral, and ground wires as shown in the wir-
ing diagram located on the unit’s blower door. For direct
vent applications, the cabinet opening to the junction box
must be sealed air tight using either an UL approved bushing
such as Heyco Liquid Tight or by applying non-reactive UL
approved sealant to bushing.
Line polarity must be observed when making field connec-
tions. Line voltage connections can be made through either
the right or left side panel. The furnace is shipped config-
ured for a right side electrical connection with the junction
box located inside the burner compartment. To make elec-
trical connections through the opposite side of the furnace,
the junction box must be relocated to the other side of the
burner compartment prior to making electrical connections.
To relocate the junction box, follow the steps shown below.
NOTE: Wire routing must not to interfere with circulator
blower operation, filter removal, or routine maintenance.
Heyco Liquid Tight or by applying non-reactive UL approved
sealant to bushing.
Line polarity must be observed when making field connec-
tions. Line voltage connections can be made through either
the right or left side panel. The furnace is shipped config-
ured for a right side electrical connection with the junction
box located inside the burner compartment. To make elec-
trical connections through the opposite side of the furnace,
the junction box must be relocated to the other side of the
burner compartment prior to making electrical connections.
To relocate the junction box, follow the steps shown below.
NOTE: Wire routing must not to interfere with circulator
blower operation, filter removal, or routine maintenance.
JUNCTION BOX RELOCATION
HIGH VOLTAGE !
T O AVOID PERSONAL INJURY OR DEATH DUE TO
ELECTRICAL SHOCK , DISCONNECT ELECTRICAL POWER
BEFORE SERVICING OR CHANGING ANY ELECTRICAL
WIRING .
WARNING
T O PREVENT UNRELIABLE OPERATION OR EQUIPMENT DAMAGE , THE
GAS MANIFOLD PRESSURE MUST BE AS SPECIFIED ON THE UNIT RATING
PLATE . O NLY MINOR ADJUSTMENTS SHOULD BE MADE BY ADJUSTING
THE GAS VALVE PRESSURE REGULATOR .
CAUTION