Daikin DM97MC Operating instructions

1
Modulating Gas Furnaces, up to 98% AFUE
34.5" Chassis DM97MC, DC97MC
& Accessories
RSD6612009r5
September2016
This manual is to be used by qualified, professionally trained HVAC technicians only. Daikin does not
assume any responsibility for property damage or personal injury due to improper service
procedures or services performed by an unqualified person.
Copyright © 2014-2016
Service Instructions

2
IMPORTANT INFORMATION
Pride and workmanship go into every product to provide our customers with quality products. It is possible,
however, that during its lifetime a product may require service. Products should be serviced only by a qualified
service technician who is familiar with the safety procedures required in the repair and who is equipped with the
proper tools,parts,testinginstrumentsandtheappropriateservicemanual. REVIEWALLSERVICE INFORMATION
IN THE APPROPRIATE SERVICE MANUAL BEFORE BEGINNING REPAIRS.
IMPORTANT NOTICES FOR CONSUMERS AND SERVICERS
RECOGNIZESAFETYSYMBOLS,WORDSANDLABELS
WARNING
TO PREVENT THE RISK OF PROPERTY DAMAGE, PERSONAL INJURY, OR DEATH,
DO NOT STORE COMBUSTIBLE MATERIALS OR USE GASOLINE OR OTHER
FLAMMABLE LIQUIDS OR VAPORS IN THE VICINITY OF THIS APPLIANCE.
TABLEOFCONTENTS
WARNING
HIGH VOLTAGE
DISCONNECT ALL POWER BEFORE SERVICING OR
INSTALLING THIS UNIT. MULTIPLE POWER SOURCES MAY
BE PRESENT. FAILURE TO DO SO MAY CAUSE PROPERTY
DAMAGE, PERSONAL INJURY OR DEATH.
IMPORTANT INFORMATION ......................2-4
PRODUCT IDENTIFICATION .................... 5 - 8
ACCESSORIES ................................... 9 - 11
LIGHTING INSTRUCTIONS .........................12
PRODUCT DESIGN ............................ 13 - 24
OPERATION .................................... 25 - 47
SERVICE AND OPERATION......................... 48
OPERATIONAL CHECKS ...................... 49 - 50
MAINTENANCE ...................................... 51
SERVICING TABLE OF CONTENTS ................ 52
SERVICING ..................................... 53 - 61
TROUBLESHOOTING.......................... 62 - 66
STATUS CODES ...................................... 67
WIRING DIAGRAM................................... 68
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 .

3
IMPORTANT INFORMATION
Tolocate an authorized servicer,please consultyour telephone bookor thedealer from whomyou purchasedthis
product. For further assistance, please contact:
CONSUMER INFORMATION LINE
DAIKIN BRAND PRODUCTS
TOLLFREE
1-855-770-5678 (U.S. only)
email us at:
[email protected]
fax us at:
[phone]
(Not a technical assistance line for dealers.)
Outside the U.S., call 1-713-861-2500.
(Not a technical assistance line for dealers.) Your telephone company will bill you for the call.

4
IMPORTANT INFORMATION
B10259-216
CO can cause serious illness including permanent brain
damage or death.
Advertencia especial para la instalación de calentadores ó 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
RISQUE D'EMPOISONNEMENT AU MONOXYDE DE CARBONE
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.

PRODUCT IDENTIFICATION
5
D M 97 M C 060 3 B N A A
SUPPLY TYPE
M: Upflow/Horizontal
C: Downflow/Horizontal
FURNACE TYPE
M: Modulating
V: 2-Stage
AFUE
97: 97% NOMINAL INPUT
060: 60,000 Btuh
080: 80,000 Btuh
100: 100,000 Btuh
120: 120,000 Btuh
AIRFLOW
CAPABILITY
@ 0.5" ESP
3: 1200
4: 1600
5: 2000
CABINET
WIDTH
B: 17-1/2"
C: 21"
D: 24-1/2"
ADDITIONAL
FEATURES
N: Natural Gas
X: Low NOx
PRODUCT
TYPE:
D: Daikin MAJOR
REVISION
A: Initial Release
MINOR
REVISION
A: Initial Release
COMMUNICATION FEATURE
C: Variable Speed/ComfortNetTM

PRODUCT IDENTIFICATION
6
MODEL: DM97MC REV AA
Equipment Type Daikin Brand Residential Gas Furnace
Heating Stages Modulating (35% - 100% of rated input)
Cooling Stages Two
Control Type ClimateTalk ™ or Conventional 24 Volt
Blower Motor Type 4 Wire Variable Speed ECM
DM97MC 0603BN 0803BN 0804CN 1005CN 1205DN
Installation Positions UF, Hor L/R UF, Hor L/R UF, Hor L/R UF, Hor L/R UF, Hor L/R
Installation Positions UF, Hor L/R UF, Hor L/R UF, Hor L/R UF, Hor L/R UF, Hor L/R
BTUH Input Range (X 1000) 21 - 60 28 - 80 28 -80 35 - 100 42 - 120
A/C Capable Tons 1.5 - 3 1.5 - 3 2 - 4 2 - 5 2 - 5
Cabinet Hight " 34.5 34.5 34.5 34.5 34.5
Cabinet Width " 17.5 17.5 21 21 24.5
Heating CFM @ 100% Firing Rate 1059 1316 1337 1870 1940
Draft Inducer3Ø Variable Speed
Gas Valve 24 VAC, Modulates by Pneumatic signal
24 VAC Heating Inputs W1 / W2
24 VAC Cooling Inputs Y1 / Y2
Primary Heat Exchanger Stainless Steel
Accessory Terminals EAC terminal, HUM IN / HUM OUT terminals
Gas Line Entry Left or Right
Revision Attributes First revision of 34.5" modulating up flow furnace
MODEL: DC97MC REV AA
Equipment Type Daikin Brand Residential Gas Furnace
Heating Stages Modulating (35% - 100% of rated input)
Cooling Stages Two
Control Type ClimateTalk ™ or Conventional 24 Volt
Blower Motor Type 4 Wire Variable Speed ECM
DC97MC 0603BN 0803BN 0804CN 1005CN
Installation Positions CF, Hor L/R CF, Hor L/R CF, Hor L/R CF, Hor L/R
BTUH Input Range (X 1000) 21 - 60 28 - 80 28 -80 35 - 100
A/C Capable Tons 1.5 - 3 1.5 - 3 2 - 4 2 - 5
Cabinet Hight " 34.5 34.5 34.5 34.5
Cabinet Width " 17.5 17.5 21 21
Heating CFM @ 100% Firing Rate 950 1146 1325 1779
Draft Inducer
Gas Valve
24 VAC Heating Inputs
24 VAC Cooling Inputs
Primary Heat Exchanger
Accessory Terminals
Gas Line Entry
Revision Attributes First revision of 34.5" modulating counter flow furnace
Left or Right
3ØVariable Speed
24 VAC, Modulates by Pneumatic signal
W1 / W2
Y1 / Y2
Stainless Steel
EAC terminal, HUM IN / HUM OUT terminals

PRODUCT IDENTIFICATION
7
MODEL # MFG # DESCRIPTION
AFE18-60A N/A
Fossil Fuel Kit. The AFE18-60Acontrol is designed for use where the indoor coil is located above/downstream
ofa gas or fossil fuel furnace when used with a heatpump.Itwill operate with single and two stage heat
pumps and single and two stage furnaces. The AFE18-60Acontrol will turn the heat pump unitoffwhen the
furnace is turned on.An anti-shortcycle feature initiates a 3 minute timed off delaywhen the compressor goes
off.
AMU1620
AMU1625
AMU2020
AMU2025
GMU1620
GMU1625
GMU2020
GMU2025
P1251305F
P1251306F
P1251307F
P1251308F
N/A
Media Air Cleaner.For use with modulating furnace models.The air cleaner is a high efficiencyair filtration
device designed to remove dirt, dust,pollen and other microscopic particles from the air passing through it.
Flexible performance range up to 2,000 CFMcapacity. The air cleaner should be installed in the system so that
all the system airis circulated through the air cleaner. The air cleaner will onlyremove the airborne
contaminants delivered to it.Maximum performance is obtained when the system blower is setfor continuous
operation. Carbon filters (optional) are available.
ASAS-10
ASAS-11
ASAS-12
ASAS-18
P1251301F
P1251302F
P1251303F
P1251304F
Electronic Air Cleaner.Foruse with variable speed,modulating furnace models. The High-Efficiency
Electronic Air Cleaner is designed to remove air contaminants down to .01 microns.Carbon filters (optional)
remove odors. Dual indicator lights show unit operation ata glance. Electronic proving switch cycles the air
cleaner On/Offwith the system fan. Durable powder-coatpaintfinish resists corrosion.
CFSB17
CFSB21
CFSB24 N/A
Counterflow Subbase Kit. For use with modulating 34.5" furnace models.These kits are available for the
following furnace widths:17.5"wide (CFSB17),21"wide (CFSB21) and 24" wide (CFSB24).The kits must be
used to preventexcessive temperature from reaching combustible materials, ifthe furnace is installed on a
combustible floor.This subbase effectivelyseparated the furnace base and plenum from combustible
materials. To ensure safe installation, do not install the counterflow floor base directlyon carpeting, tile, or
other combustible material other than wood flooring.
CTK01 CTK01AA
Communicating Thermostat Kit-Digitallycommunicating touchscreen thermostat, a necessarypartof any
communicating system.Designed for use with compatible Daikin Air Handlers or Furnaces and outdoor split
AC orHeatPump units.This thermostatsupports up to three stages ofheat,two stages ofcooling, dual fuel
applications,dehumidification,filter maintenance reminders, outdoor temperature displayand advanced
menus including diagnostics.The CTK01AAkitincludes a communicating touchscreen thermostat and sub
base, 230V-24V40va transformer, terminal blocks(2), wire jumpers,
mounting screws, installation manual and homeowner guide.
CTK01BA CTK01BA
Communicating Thermostat Kit-Digitallycommunicating touchscreen thermostat, a necessarypartof any
communicating system.Designed for use with compatible Daikin Air Handlers or Furnaces and outdoor split
AC orHeatPump units.This thermostatsupports up to three stages ofheat,two stages ofcooling, dual fuel
applications,dehumidification,filter maintenance reminders, outdoor temperature displayand advanced
menus including diagnostics.The CTK01BAkitincludes a communicating touchscreen thermostatand sub
base,terminal blocks(2),mounting screws, installation manual and homeowner guide.
CTK02** CTK02**
Communicating Thermostat Kit-Digitallycommunicating thermostat, a necessarypartof anycommunicating
system. Designed for use with compatible Daikin Air Handlers or Furnaces and outdoor split AC or Heat Pump
units. The CTK02** thermostatfeatures full color,high definition display, advanced programming options
including humidification control & heatand cool maximum temperature settings, a USBplug allowing dealers
the abilityto insertpre-programmed operating parameters and dealerinformation byuse of an online data
entrysystem.
CTK03A* CTK03A*
Communicating Thermostat Kit-Digitallycommunicating touchscreen thermostatfrom Honeywell.Designed
for use with compatible Daikin Air Handlers or Furnaces and outdoorsplit AC or HeatPump units.The
CTK03A* thermostat features full color high definition display,can be used with RedLINK wireless
accessories.
CTK04A* CTK04A*
Communicating Thermostat Kit-Digitallycommunicating touchscreen thermostatfrom Honeywell.Designed
for use with compatible Daikin Air Handlers or Furnaces and outdoorsplit AC or HeatPump units.The
CTK04A* thermostat features full color high definition display,can be used with RedLINK wireless
accessories. Splitsystem inverter capable.

PRODUCT IDENTIFICATION
8
MODEL # MFG # DESCRIPTION
DCVK-20
(CVENT-2)
DCVK-30
(CVENT-3)
N/A
Concentric Vent Kit. For use with Daikin Modulating furnace models. This kitis designed to allow terminations
ofa directvent furnace to be "concentrically"vented through a wall or roof.This kitallows a single penetration to
supportterminations for both the vent/flue and the combustion air intake pipe.The DCVK-20 (2") and DCVK-30
(3") kits are certified formodels listed above. See specification sheets on future models for use of the ventkit.
DEHUM1 P1227801F
Dehumidistat. For use with Daikin two-stage variable speed modulating furnace models.Wall mounted,24 volt
humiditycontrol available as a Dehumidistatused to reduce the airflow in the air conditioning mode when
necessaryto lower the humidityin an occupied home to preventdew build-up associated with high humidity
levels.This control features a moisture-sensitive nylon elementand also provides positive ON-OFFsettings for
manual operation.The control is a normallyclosed switch thatopens on humidityrise causing the blowerto
switch to a lowerspeed to control the humiditywithin the structure.
EFR02 N/A
ExternalFilter Rack Kit.For use with Daikin 97% upflow,variable speed *MVM34.5" modulating gas furnaces.
This kitis intended to provide a location,external to the furnace casing forinstallation ofa permanentfilter.The
rack is mounted over the indoor air blower compartment area of either side panel,and provide filter retention
as well as a location for attaching return air ductwork.
0170K00000S N/A Side Wall Only Concentric Vent Kit. For use with 97% modulating furnace models. This kit is to be used with
2"- 3"ventsystems.The ventkitmustterminate outside the structure. This kit is NOTintended for use with
single pipe (indirectvent) installations.
0170K00001S N/A Side Wall Only Concentric Vent Kit. For use with 97% modulating furnace models. This kit is to be used with
2"vent systems.The ventkitmustterminate outside the structure. This kitis NOTintended for use with single
pipe (indirect vent) installation
LPLP03 N/A LP Gas Low Pressure Kit.The kitmonitors gas line pressure with a pressure switch and will open the circuit
to the gas valve ifthe LP tank pressure gets low.
LPM-09 N/A LP Conversion Kit Converts a 34.5"modulating furnace to operate on L.P.gas. The kitcontains an L.P.gas
valve and a setofsixL.P.orifices.
RF000142 N/A Drain Coupling Kit Foruse when the drain/ventelbow has been removed in a horizontal leftinstallation.This
kitprevents condensate from getting in the inducerand routes the condensate to a drain.

ACCESSORIES
9
Model
Number
AFE180-60A
AMU / GMU
ASAS / GSAS
CFSB17 CFSB21 CFSB24
RF000142
CTK01* CTK02* CTK03* CTK04*
Description
Fossil Fuel Kit
Media Air Cleaners
Electronic
Air Cleaner
Counterflow Subbase
17.5"
Counterflow Subbase
21"
Counterflow Subbase
24.5"
Drain Coupling
Kit
Communicating
Thermostat Kit
Com Thermostat Kit- Modulating, High Def. Com Thermostat Kit-
Modulating, High Def
Com Thermostat Kit-
Modulating, High Def
DM97MC0603BN** X X X XXXX X
DM97MC0803BN** X X X XXXX X
DM97MC0804CN** X X X XXXX X
DM97MC1005CN**XXX XXXX X
DM97MC1205DN**XXX XXXX X
DC97MC0603BN**XXXX XXXX X
DC97MC0803BN**XXXX XXXX X
DC97MC0804CN**XXX X XXXX X
DC97MC1005CN**XXX XXXX X
Model
Number
0170K00000S 0170K00001S
DCVK-20
(C-CVENT2)
DCVK-30
(CVENT-3)
DEHUM1
EFR02
LPLP03 LPM-09
Description
Concentric Side Wall
Vent Kit (3")
Concentric Side Wall
Vent Kit (2")
Concentric Vent Kit (2") Concentric Vent Kit (3")
Dehumidistat
External Filter Kit
Low LP Tank Protection
L.P. Kit
DM97MC0603BN** X XXXXXXX
DM97MC0803BN** X XXXXXXX
DM97MC0804CN** X XXXXXXX
DM97MC1005CN**XXXXXXXX
DM97MC1205DN**XXXXXXXX
DC97MC0603BN**XXXXX XX
DC97MC0803BN**XXXXX XX
DC97MC0804CN**XXXXX XX
DC97MC1005CN**XXXXX XX
97% Mod Furnace Accessories

ACCESSORIES
10
Vent
Maintain 12" (18" for Canada)
minimum clearance above highest
anticipated snow level. Maximum of
24" above roof.
Combustion Air
Roof Boot/Flashing
(Field Supplied)
Support (Field Supplied)
45 Elbow
(Field Supplied)
Combustion Air
Vent
CONCENTRIC VENT CONVERSION KIT (DCVK-20 & DCVK-30 [CVENT-2 & CVENT-3*])
DCVK
(Vertical Installation)
DCVK
(Horizontal Installation)
The DCVK-20 (2") or the DCVK-30 (3") is a concentric vent
kit approved with furnaces listed in this manual.
This concentric vent kit allows for vertical or horizontal
vent termination. The illustrations give a brief view of
the kit and its application.
Vent
Combustion Air
Flush to
1" maximum
45 Elbow
(Field Supplied)
Combustion Air
Vent Strap
(Field Supplied)
EXTERNAL FILTER RACK (EFR02)
Used on 97% Upflow Modulating Furnaces
BLOWER DECK
SCREWS
SLOTS IN FILTER
CLEAR SCREWS
ON UNIT
FRONT
OF UNIT
RETURN AIR
CUTOUT AREA LOWER EDGE
SCREW
FILTER RACK ASSEMBLY
(FACE FILTER OPENING
TOWARDS FRONT
OF UNIT)
UNIT SIDE
PANEL
BASE
OF UNIT
See the section in this manual under "Vent Flue and Com-
bustion Air Pipe Terminations" for more information or
consult the Installation and Operating Instructions (IO-
619*).
DCVK-20 & DCVK-30 are also known as CVENT-2 & CVENT-3

ACCESSORIES
11
SIDE WALL VENT KIT (0170K00000S)
This side wall only vent kit #0170K00000S is to be used
with 2” - 3” vent systems. This kit is NOT intended for
use with single pipe (non-direct vent) installations.
The vent kit must terminate outside the structure and may
beinstalled with theintake andexhaust pipeslocated side-
by-side or with one pipe above the other.
See the section in this manual under "Vent Flue and Com-
bustion Air Pipe Terminations" for more information or
consult the Installation Instructions (IO-635).
SIDE WALL VENT KIT (0170K00001S)
This side wall only vent kit #0170K00001S is to be used
with 2” vent systems. This kit is NOT intended for use
with single pipe (non-direct vent) installations.
The vent kit must terminate outside the structure and may
beinstalled with theintake andexhaust pipeslocated side-
by-side or with one pipe above the other.
See the section in this manual under "Vent Flue and Com-
bustion Air Pipe Terminations" for more information or
consult the Installation Instructions (IO-805).
LPLP03 LOW LP GAS PRESSURE SHUT-OFF KIT
Installation of the LPLP03 kit is recommended on every LP
converted furnace to protect the furnace against low LP
gas supply pressure. Low LP supply pressure can cause poor
combustion and carbon in the heat exchanger. The LPLP03
kit will open the electrical circuit to the gas valve in the
event of low supply pressure. The kit contains a pressure
switch, gas fittings and electrical harness to connect the
switch in series with the gas valve.
LPM-09 LP CONVERSION KIT
This furnace is factory equipped to operate on Natural Gas
but may be field converted to operate on LP gas. To con-
vert a DM97MC or DC97MC furnace to operate on LP gas,
the LPM-09 conversion kit must be used. The LPM-09 kit
contains a modulating gas valve ready for use with LP gas,
as well as a set of 1.25 mm orifices to replace the factory
installed natural gas orifices. Do not attempt to convert a
modulating furnace gas valve. Factory burners are suit-
able for both gases, L.P. and Natural. Burner replacement
is not required when the furnace is converted for use with
L.P. gas.
AFE18-60A DUAL FUEL ACCESSORY
When installing the modulating furnace with a heat pump,
the preferred installation would include a communicating
thermostat. A communicating thermostat provides control
of gas heat and heat pump operation and eliminates the
need for a separate dual fuel control. A legacy dual fuel
thermostat could also be used with 24 volt wiring to con-
trol the gas furnace and heat pump. If a communicating
thermostat or legacy dual fuel thermostat are not used,
the AFE18-60A kit must be added to provide control of the
equipment. This control is mounted indoors near the fur-
nace and provides terminals for thermostat, furnace, and
heat pump wiring. The AFE18-60A may be used with or
without a separate outdoor thermostat.
OT18-60A OUTDOOR THERMOSTAT
For use in a legacy dual fuel installation to lock-out the
heat pump at a selected temperature.
CFSB17, 21, 24 COUNTER FLOW BASE
The CFSB base must be used when installing a DC97MC
furnacein the verticalposition ona combustiblefloor with-
out a coil under the furnace.
Mod e l Primary Limit
Settin
g
Primary Limit
Pt #
Aux Limit
Setting
Aux Limit Pt #
(qty 2)
R.O.S Limit
Settin
g
R.O.S. Limit Pt
#
DM97MC0603BNAA 150 ±5 20162904 120 0130F00038 300 ±9 10123529
DM97MC0803BNAA 170 ±5 20162906 120 0130F00038 300 ±9 10123529
DM97MC0804CNAA 150 ±5 20162904 120 0130F00038 300 ±9 10123529
DM97MC1005CNAA 160 ±5 20162903 120 0130F00038 300 ±9 10123529
DM97MC1205DNAA 180 ±5 0130F00036 120 0130F00038 300 ±9 10123529
DC97MC0603BNAA 180 ±5 0130F00036 120 0130F00038 300 ±9 10123529
DC97MC0803BNAA 150 ±5 20162904 120 0130F00038 300 ±9 10123529
DM97MC0804CNAA 210 ±6 20162901 120 0130F00038 300 ±9 10123529
DM97MC1005CNAA 180 ±5 0130F00036 120 0130F00038 300 ±9 10123529

12
LIGHTING INSTRUCTIONS
INLET
"ON/MARCHE"
LEVERSHOWN
0140F01910-A
1.Readthesafetyinfrmationaboveon
"OFF"
Immediatelycallaqualifiedservicetechniciantoinspect
STOP."B"
11.Sil'appareilnesemetpasenmarche,suivreles
B.AVANTDELEFAIREFONCTIONNER,
Donotforce.
devicewhichautomaticallylightstheburner.
inthesafety.informationabove
systémedecontrôleettoutecommandequiontété
instructionsintituléesCommentcouperl'admission
1.Réglerlethermostatàlatempératurelaplusbassé.
l'eau,mêmepartiellement.Faireinspecterl'appareil
2.Réglerlethermostatàlatempératurelaplusbasse.
Donottrytolightanyappliance.
qu'àlamain.Nejamaisemploerd'outilàcettefin.
ifserviceistobeperformed.
hand,don'ttrytorepairit,callaqualifiedservice
7.Pushgascontrollever
servicetechnicianorgascompany.
munid'undispositifd'allumagequiallume
theapplianceandtoreplaceanypartofthecontrol
certainsgazsontpluslourdsquel'airet
appelezleservicedesincendies.»
ROBINETAGAZ
qualifiéoulefournisseurdegaz.
C.Useonlyyourhandtopushinorturnthegascontrollever.
AVERTISSEMENT:
to
Immediatelycallyourgassupplierfromaneighbor's
S'iln'yapasd'odeurdegaz,passeràl'etàpesuivante.
9.Turnonallelectric
BEFOREOPERATING
POURCOUPERL'ADMISSION
paruntechnicienqualifiéetremplacertoutrpartiedu
Donotforce.
powertotheappliance.
tentedeforcerlamanetteoudelaréparerpeut
automatiquementlebrûleur.Nepastenter
MANUALGAS
Nepastenterd'allumerd'appareils.
exactly,afireor
Nepasforcer.
4.Remettreenplacelepanneaud'accés.
donotuseanyphoneinyourbuilding.
allumerlebrûleurmanuellement.
2.Setthethermostattolowestsetting.
TOTURNOFFGASTOAPPLIANCE
Passeràl'etapeBdesinstructionsdesecurite
5.PousselelevierducontrÔledugaza
7.Pousselelevierducontrôledugazà
B.smellallaroundtheappliance
GAS
Cetappareilnecomportepasdeveilleuse.Ilest
"ON".
Appelezimmédiatementvotrefournisseurdegazdepuis
4.Cetappareilmenageretantdoted'unsysteme
withanignitiondevicewhichautomaticallylights
3.Pousselelevierducontrôledugazà
degazdel'appareiletappeleruntechnicien
3.PushthegascontrollevertoPosition.
position.
ARRÊTEZ
.
8.Remettreenplacelepanneaud'accés.
tolighttheburnerbyhand.
OPERATINGINSTRUCTIONS
smellforgas,includingnearthefloor.Ifyou
"OFF"
QUEFAIRES'ILYAUNEODEURDEGAZ
technician.Forceorattemptedrepairmayresultinafire
11.Iftheappliancewillnotoperate,
callthefiredepartment.
plongéesdansl'eau.»
unvoisin.Suivezlesinstructionsdufournisseurdegaz
thislabel.
d'allumerlebrûleurmanuellement.
"ON/MARCHE"
MANUEL,ENPOS
explosionmayresultcausingproperty
reniflertoutautourdel'apparielpourdecéler
"OFF/ARRET"
corporellesoulapertedevieshumaines.
d'allumageautomatique,nepasessayerà
4.Replacecontrolaccesspanel.
"ON/MARCHE"
followtheinstructions"ToTurn
lalettrelesinstructionsdanslepreséntmanuel
D.Donotusethisapplianceifanyparthasbeenunderwater.
position.
6.Attendrecinq(5)minutespourlaisserechappertoutle
LEVERSHOWN
WHATTODOIFYOUSMELLGAS
5.PushthegascontrollevertoPosition.
"OFF/ARRET"
settleonthefloor.
sectionsupérieuredecetteétiquette.
D.Nepasseservirdecetappareils'ilaétéplongédans
provoqueruneexplosionouunincendie.»
destéléphonesdanslebâtiment.
8.Replaceaccesspanel.
Donottrytolighttheburnerbyhand.
damage,personalinjuryor
areaforgas.Besuretosmellnexttothefloor
Neverusetools.Iftheleverwillnotpushinorturnby
READBEFOREOPERATING
Silamanetterestecoincée,netenterpasdela
ENMARCHELIRE
INLET
position.
peuvents'accumulerauniveaudusol.
réparer;appelezuntechnicienqualifié.Quiconque
Sivousnepouvezrejoindrelefournisseurdegaz,
1.Setthethermostattolowestsetting.
4.Thisapplianceisequippedwithanignition
10.Setthermostattodesiredsetting.
A.
DUGAZ
STOP.
LIREAVANTDEMETTRE
C.Nepousseroutournerlamanetted'admissiondugaz
gaz.Reniflertoutautourdel'appareil,ycomprisprésdu
IN"ON"POS
10.Réglerlethermostatàlatempératuredésirée.
lossoflife.
Ifyoucannotreachyourgassupplier,
OffGasToAppliance"andcallyour
plancher,pourdéceleruneodeurdegaz.Sic'estlecas,
0140F01910-A
Donottouchanyelectricswitch;
6.Waitfive(5)minutestoclearoutanygas.Then
becausesomegasisheavierthanairandwill
1.Lisezlesinstructionsdesécuritédansla
thensmellgas,Follow
3.Couperl'alimentationélectriquedel'appareil.
Netoucheràaucuninterrupteur;nepasvousservir
9.Mettrel'appareilsoustension.
MISEENMARCHE
uneodeurdegaz.Reniflerprésduplancher,car
ARRÊTEZ.
Ifyoudonotfollowtheseinstructions
surlaportionsuperieuredecetteetiquette.
3.Turnoffallelectricpowertotheappliance.
fautprocéderàdesoperationsd'entretien.
gas,gotonextstep.
orexplosion.
FORYOURSAFETY
entraînantdesdommagesmatériels,deslesions
2.Turnoffallelectricpowertotheappliance
A.Thisappliancedoesnothaveapilot.Itisequipped
theburner.Donottry
ARRIVEE
DEGAZDEL'APPAREIL
phone.Followthegassupplier'sinstructions.
onthislabelifyoudon'tsmell
systemandanygascontrolwhichhasbeenunderwater.
Quiconquenerespectepasà
2.Couperl'alimentationélectriquedel'appareils'il
MANUEL,ENPOS
ARRIVEE
IN"ON"POS
DUGAZ
GAS
risquededéclencherunincendieouuneexplosion
ROBINETAGAZ
MANUALGAS
WARNING:

PRODUCT DESIGN
13
Adhere to the following warnings and cautions when installing, 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.
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
B10259-216
CO can cause serious illness including permanent brain
damage or death.
Advertencia especial para la instalación de calentadores ó 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
RISQUE D'EMPOISONNEMENT AU MONOXYDE DE CARBONE
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.
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

PRODUCT DESIGN
14
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
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
Electrostatic Discharge (ESD) Precautions
NOTE: Dischargeyourbody’sstaticelectricitybefore touch-
ing unit. An electrostatic discharge can adversely affect
electricalcomponents.
Use the following precautions during furnace installation
andservicing to protect the integratedcontrol module from
damage. By putting the furnace, the control, and the per-
son at the same electrostatic potential, these steps will
help avoid exposing the integrated control module to elec-
trostatic discharge. This procedure is applicable to both
installed and non-installed (ungrounded) furnaces.
1. Disconnect all power to the furnace. Do not touch
the integrated control module or any wire connected
to the control prior to discharging your body’s elec-
trostatic charge to ground.
2. Firmly touch a clean, unpainted, metal surface of the
furnaces near the control. Any tools held in a
person’s hand during grounding will be discharged.
3. Service integrated control module or connecting wir-
ing following the discharge process in step 2. Use
caution not to recharge your body with static elec-
tricity; (i.e., do not move or shuffle your feet, do
not touch ungrounded objects, etc.). If you come in
contact with an ungrounded object, repeat step 2 be-
fore touching control or 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. Re-
turn any old or new controls to their containers be-
fore touching any ungrounded object.
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
Introduction
This is a Category lV furnace. This furnace uses a pressur-
ized venting system and must be installed per National and
local codes requirements and the installation manual that
was shipped with the furnace.
Our 34.5" modulating furnace is one of the products in our
newly redesigned line of shorter chassis furnaces. It comes
in two models: an up flow / horizontal model and a down
flow / horizontal model.
The up flow / horizontal 34.5" modulating furnace is avail-
able in the following nominal capacities: 60,000 BTUH – 3
ton drive; 80,000 BTUH – 3 ton drive; 80,000 BTUH – 4 ton
drive; 100,000 BTUH – 5 ton drive; 120,000 BTUH – 5 ton
drive.
DM97MC0603BN**
DM97MC0803BN**
DM97MC0804CN**
DM97MC1005CN**
DM97MC1205DN**
The down flow / horizontal 34.5" modulating furnace is
available in the following nominal capacities: capacities:
60,000 BTUH – 3 ton drive; 80,000 BTUH – 3 ton drive;
80,000 BTUH – 4 ton drive; 100,000 BTUH – 5 ton drive.
DC97MC0603BN**
DC97MC0803BN**
DC97MC0804CN**
DC97MC1005CN**
Product Description
Features
General Information
The modulating furnace is part of our family of communi-
cating ready products. The furnace may be used with con-
ventional single or multi-stage thermostats as well as our
CTK01 communicating thermostats & CTK02**, CTK03 and
CTK04 communicating-modulating thermostats using the
ClimateTalk™ communicating protocol. Burner manifold
pressure is controlled by negative air pressure created by
the draft inducer. Gas valve, pressure switch assembly,
and induced draft blower are linked together by pneumatic
tubing. The furnace features a Honeywell gas valve ca-
pable of variable gas input rates as low as 35% and up to
100% of rated input. Indoor air is delivered by a variable
speed ECM motor which bases the CFM need off of the
burner input. The modulating furnace operation is based
off of negative pressure created by the draft inducer. The
Integrated Furnace Control (IFC) receives commands from
the room thermostat. The IFC then controls the RPM of the
(3 phase) inducer by varying the frequency and voltage to
theinducer.Thisisknownasvariablefrequencydrive (VFD).

PRODUCT DESIGN
15
Acceptable Equipment Combinations
With CTK0* Communicating Thermostat:
1. Modulating furnace alone
2. Modulating furnace with Daikin communicating split
A/C or H/P unit (no separate dual fuel control is re-
quired)
3. Modulating furnace with non-communicating 1 stage
A/C split unit (can not support a 2 stage A/C or a
non-communicating heat pump).
With Conventional Non-Communicating Thermostat
(Single or Multi-Stage)
1. Modulating furnace alone.
2. Modulating furnace with Daikin communicating split
A/C or H/P unit (a dual fuel thermostat or separate
dual fuel control is required for H/P).
3. Modulating furnace with non-communicating splitA/
C or H/P (a dual fuel thermostat or separate dual
fuel control is required for H/P).
ProductApplication
This furnace is primarily designed for residential home-
heating 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
commercial 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:
• Itmustbeinstalled pertheinstallationinstructionspro-
videdandperlocaland nationalcodes.
• Itmust beinstalledindoorsin abuildingconstructedon
site.
• Itmustbepartofaductedsystem andnotusedinafree
airdeliveryapplication.
• It must not be used as a “make-up” air unit.
• It must be installed with two-pipe systems for combus-
tion air.
• AllotherwarrantyexclusionsandrestrictionsapplyThis
furnaceis anETLdual-certifiedappliance and isappro-
priate for use with natural or propane gas (NOTE: If
using propane, a propane conversion kit is required).
Dual certification means that the combustion air inlet pipe is
optionaland the furnace canbe ventedas a:
Non-directvent(singlepipe) central forced air furnace
in which combustion air is taken from the installation
area or from air ducted from the outside or,
Directvent(dualpipe)centralforcedairfurnace inwhich
allcombustionairsupplieddirectlyto thefurnaceburn-
ersthrough a field installed combustion air pipe.
This furnace may be used as a construction site heater ONLY
if allofthe following conditions are met:
This furnace may be used as a construction site heater
ONLY if all of the following conditions are met:
• The vent system is permanently installed per these
installation instructions.
• A room thermostat is used to control the furnace.
Fixed jumpers that provide continuous heating CAN-
NOT be used and can cause long term equipment
damage. Bi-metal thermostats, or any thermostat
affected by vibration must not be used during con-
struction.
• Return air ducts are provided and sealed to the fur-
nace.
• A return air temperature range between 60ºF (16ºC)
and 80ºF (27ºC) is maintained.
• Air filters are installed in the system and replaced
daily during construction and upon completion of
construction.
• The input rate and temperature rise are set per the
furnace rating plate.
• The furnace must be installed as a two pipe system,
using 100% outside air for combustion during con-
struction.
• The furnace heat exchanger, components, duct sys-
tem, air filters and evaporator coils are thoroughly
cleaned following final construction clean up by a
qualified person.
• All furnace operating conditions (including ignition,
input rate, temperature rise and venting) are veri-
fied by a qualified person according to these instal-
lation instructions.
• Furnace doors must be in place on the furnace while
the furnace is operating in any mode.
• Damageorrepairs due to failure tocomply with these
requirements is not covered under the warranty.
NOTE: The Commonwealth of Massachusetts requires that
thefollowing additionalrequirementsmustalso bemet:
• Gasfurnacesmustbeinstalledbyalicensedplumberor
gas fitter.
• A T-handle gas cock must be used.
• If the unit is to be installed in an attic, the passageway
toandtheservice areaaroundtheunitmusthavefloor-
ing.

16
To ensure proper furnace operation, install, operate and
maintain the furnace in accordance with the installation
manual shipped with the furnace as well asall localbuild-
ing codes and ordinances. In their absence, follow the latest
edition of the National Fuel Gas Code (NFPA 54/ANSI Z223.1),
and/orCAN/CSAB149InstallationCodes,localplumbingorwaste
watercodes,andotherapplicablecodes.
A copy of the National Fuel Gas Code (NFPA 54/ANSI Z223.1)
canbe obtainedfromanyof the following:
American National Standards Institute
25 West 43rd Street, 4th Floor
New York, NY 10036
NationalFire Protection Association
1BatterymarchPark
Quincy, MA 02169-7471
CSA International
8501EastPleasantValley
Cleveland,OH 44131
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
orin accordance with“ASHRAE Guide”or“Manual J-Load Cal-
culations” published by the Air Conditioning Contractors of
America.
FURNACE INSTALLATION REQUIREMENTS
Thoroughly read the Installation Manual shipped with the
furnace before conducting installation or repairs.
• Centrallylocatethefurnacewithrespecttotheproposed
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.
• Provideprovisionsfor venting combustion products out-
doors through a proper venting system. Special consid-
eration should be given to vent/flue pipe routing and
combustion air intake pipe when applicable. Refer to
Vent/Flue Pipe and Combustion Air Pipe -Termination
Locations for appropriate termination locations and to
determineif thepipingsystem fromfurnacetotermina-
tion can be accomplished within the guidelines 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
temperatureswithoutproperfreezeprotection.Referto
CondensateDrain Lines andTrap forfurtherdetails.
• Ensureadequate combustion air isavailable forthe fur-
nace. Improper or insufficient combustion air can ex-
posebuildingoccupantstogascombustionproductsthat
could include carbon monoxide. Refer to Combustion
andVentilationAirRequirements.
• Setthefurnaceonalevelfloortoenableproperconden-
satedrainage. Ifthefloorbecomeswetordampattimes,
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 Con-
siderationsforlevelingofhorizontalfurnaces.
• Ensureupfloworhorizontalfurnacesarenotinstalleddi-
rectly on carpeting, or any other combustible material.
Theonlycombustiblematerialallowediswood.
• A special accessory subbase must be used for upright
counterflowunit installationsoveranycombustible ma-
terial (including wood). Refer to subbase instructions
for installation details. (NOTE: A subbase will not be
requiredifanairconditioningcoilislocated beneaththe
furnacebetweenthesupplyairopeningandthecombus-
tiblefloor.
• Exposure to contaminated combustion air will result in
safetyandperformance-relatedproblems. Donotinstall
the furnace where the combustion air is exposed to the
followingsubstances:
permanentwavesolutions
chlorinatedwaxesorcleaners
chlorine-basedswimmingpoolchemicals
watersofteningchemicals
deicingsalts or chemicals
carbontetrachloride
halogentype refrigerants
cleaningsolutions(suchasperchloroethylene)
printing inks
paint removers
varnishes
hydrochloricacid
cementsand glues
antistaticfabric softeners forclothesdryers
andmasonry acid washingmaterials
• Isolate a non-direct furnace from an area contami-
nated by any of the above substances. This protects
thenon-directventfurnacefromairbornecontaminants.
Toensurethattheenclosed non-directventfurnacehas
anadequatesupplyofcombustionair,ventfromanearby
uncontaminated room or from outdoors. Refer to the
CombustionandVentilationAirRequirementsfordetails.
• If the furnace is used in connection with a cooling
unit, install the furnace upstream or in parallel with
the cooling coil. Premature heat exchanger failure
will result if the cooling coil is placed upstream of the
furnace.
PRODUCT DESIGN

17
For vertical (upflow or downflow) applications, the
minimum cooling coil width shall not be less than fur-
nace width minus 1”. Additionally, a coil installed
above an upflow furnace or under a counterflow fur-
nace 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 fur-
nace.
For upflow applications, the front of the coil and fur-
nace must face the same direction.
• If the furnace is installed in a residential garage, posi-
tion the furnace so that the burners and ignition source
are located not less than 18 inches (457 mm) above the
floor. Protectthe furnace from physicaldamagebyve-
hicles.
• Ifthefurnaceisinstalledhorizontally, ensuretheaccess
doors are not on the “up/top” or “down/bottom” side
ofthe furnace.
• Donotconnectthisfurnacetoachimneyfluethatserves
aseparate appliancedesignedtoburnsolid fuel.
• On Counterflow Installations, the air conditioning coil
mustbedownstreamonthesupply(positive)sideofthe
furnaceheatexchanger.
•Counterflow Installation over a noncombustible floor.
Beforesettingthefurnaceovertheplenumopening,en-
surethesurfacearoundtheopeningissmoothandlevel.
A tight seal should be made between the furnace base
and floor by using a silicone rubber caulking compound
orcement grout.
•CounterflowInstallationoveracombustiblefloor.If in-
stallation over a combustible floor becomes necessary,
use an accessory subbase (see Specification Sheet ap-
plicablefor yourmodelfordetails.) A specialaccessory
subbase must be used for upright counterflow unit in-
stallationsoveranycombustiblematerialincludingwood.
Refer to subbase instructions for installation details.
Follow the instructions with the subbase for proper in-
stallation.
Do not install the furnace directly on carpeting, tile, or
other combustible material other than wood flooring.
(NOTE:Thesubbasewillnotbe requiredifanaircondi-
tioning coil is installed between the supply air opening
onthefurnaceandthefloor.)
Furnace Components
Heat Exchanger Assembly
The primary heat exchanger is a tubular type constructed
of high quality steel (409 stainless steel for the heat ex-
changer assembly consists of primary and secondary sec-
tions crimped together on a back transition plate. The sec-
ondary heat exchanger is a single pass coil consisting of
AL29-4C stainless steel tubes and aluminum fins. These
stainless steel tubes are expanded on to the aluminum fins
to enhance heat transfer. Each tube in the secondary heat
exchangercontains an internal turbulatortoeffectivelyscrub
heat from the flue gases. The primary and secondary heat
exchangersections are joined bya 441 stainlesssteel header
plate. Flue gas condensation takes place in the secondary
heat exchanger as latent heat is transferred from the flue
gases to heat the conditioned space.
Burners
Burners have been redesigned for 34.5" chassis furnaces.
Overall length and width dimensions remain the same as
40" model burners. The burners used 34.5" models have
burner head insert with larger diameter center hole and a
larger number of surrounding holes.
New 34.5 Burner
Dependingon the sizeof the furnace,each furnacewill have
from three to six inshot burners. Burners are precisely con-
structed of aluminized steel and designed to provide proper
ignition and flame stability.
Gas Manifold Assembly
Each gas manifold is fitted with the appropriate number of
#45 natural gas orifices. At 100% of gas input, each burner
will provide approximately 20,000 BTUH. If converting to
LP gas, the factory installed manifold assembly must be
replaced by the manifold assembly provided in the LP kit.
ECM Motor
A variable speed ECM four wire indoor fan motor provides
supply air to the conditioned space. This is the same motor
used on previous generation communicating furnaces.
Induced Draft Blower (IDB)
All modulating furnace models use a three phase induced
draftblower to drawflue gasesthroughthe heat exchanger.
The inducer uses ball bearings and is permanently lubri-
cated. This motor is driven at varying speeds by the VFD
(variable frequency drive) section of the IFC. The IFC takes
typical single phase power supplied to the furnace and con-
PRODUCT DESIGN

18
verts it to a three phase supply to operate the draft inducer
at the desired speed. The windings of the induced draft
motor will have equal resistance +/- 5%. Normal resistance
readings at room temperature will range from 14-17 ohms.
The voltage supplied by the IFC to drive the induced draft
blower will vary from 15-110 volts A/C between any two
windings. This would be read between any two of the three
power wires between the IFC and the induced draft blower.
This voltage to the IBD will vary between furnace models
and is dependant on what percentage of maximum fire is
being called for. The power wires are colored red, white,
and black. A green colored ground wire is also present.
Hot Surface Igniter
Modulating furnaces use a 115 volt silicon nitride hot sur-
face igniter. This is the familiar and reliable 0131F00008S
igniter with 17 second warm up time. At room temperature
the igniter has a resistance range of 37 - 68 ohms. The
H.S.I. is connected electrically to the IFC by a 3/16" push-
on connection.
Gas Valve
Modulating furnaces use a 24 VAC pneumatically operated
gas valve by Honeywell. The valve is energized by the inte-
grated furnace control on a call for heat, wired in series
throughthe front-cover pressureswitch. Thefiring rateper-
centage is determined by the negative pressure created by
the operation of the draft inducer.
Inductor Coil
Wired in series with ¾ and 1 HP ECM motors; the inductor
coil conditions the power supply to the motor, smoothing
out spikes and electrical noise. With voltage applied to one
side of the inductor coil, the output voltage to the motor
should be the same as incoming voltage.
Integrated Furnace Control (IFC)
The IFC is the main control center for the furnace. It has
many functions including;
• Receiving commands from the thermostat for heat-
ing, and cooling, continuous fan operation.
• Receivingcommandsfordehumidification and humidi-
fication.
• Communicating with the ECM motor for proper air
delivery to the conditioned space.
• Assuring safe ignition by checking the state of pres-
sure switches and limit switches before and after ig-
nition.
• Assuring safe operation by continuously monitoring
the presence of flame, the state of the pressure
switches and limit and roll out switches.
• Displays information on the dual seven segment dis-
plays regarding thermostat call, air flow delivery and
fault status
• Controlling the speed of the induced draft blower by
variable voltage & frequency.
Features of the IFC:
Aux Terminals Located next to the low voltage connector,
there are two terminals labeled aux in & aux out. A factory
jumper is installed between these two terminals. As an op-
tion; the jumper may be removed and the terminals wired
up to a normally closed float switch. The switch must be
closed for normal operation. If the switch is sensed open,
the IFC will:
• Terminate a call for gas heat.
• When the modulating furnace is installed with a com-
municating thermostat and a non-communicating a/
c unit, the IFC will open the Y1 relay to turn off the
condensing unit
• Log and display an auxiliary open error code
• Once the auxiliary switch re-closes the IFC reverts
back to normal operation
Hum Terminals A pair of ¼” HUM terminals are located on
the board to power a humidifier. These are dry contacts
ratedat 1 amp. A typicalapplication of thesecontacts would
be to supply one of the Hum contacts with power from the
L1 terminal and connect the remaining Hum terminal to a
humidifier transformer primary. When used with the
CTK02**, CTK03 and CTK04 thermostats, these contacts will
close with a call for humidity and the furnace indoor blower
will be powered at continuous fan speed. When used with a
24 volt control system, the Hum contacts will close on a call
for heat when the induced draft blower is powered.
EAC Terminal A ¼” EAC terminal is provided. Any time
the indoor blower motor is powered, the EAC terminal will
be powered. Contact is rated for 1 amp
Flame Proving. Flame signal is continuously monitored by
the IFC. The flame rod, flame rod wire and proper ground-
ing are all critical to proving the presence of flame. Be-
cause of the design of the Honeywell flame proving system,
reading flame signal with a microamp meter will not pro-
vide reliable and consistent results and is therefore not a
recommended practice. The IFC has a built in warning (E6)
if flame signal is approaching the low threshold.
Field Test Mode This feature can be used by the service
technician to quickly bring a furnace up to high fire. Enter-
ing field test mode will by-pass the staging routine and al-
low the furnace to run at 100% of rated input. To use field
test mode; during a call for heat, press the fault recall but-
ton twice within 5 seconds, the display will change to Ft,
then press and hold the fault recall button for a few seconds
until the display flashes Ft. The furnace will stay in field
test mode for 5 minutes or until the call for heat is re-
moved.
Dual 7 Segment Displays The modulating furnace IFC has
dual 7 segment displays to provide service information. This
informationincludes; present thermostat demand, CFM,and
fault codes.
PRODUCT DESIGN

19
Fault Recall This feature allows the service person to check
for any fault history. The board memory is capable of re-
cording and storing 10 fault codes. To use this feature, the
furnace must not have an existing thermostat call. Pres-
sure fault recall button from 2-5 seconds (until the display
goes blank) then release, all faults will be displayed one at
a time, beginning with the most recent, max of 3 consecu-
tive faults will be stored. When all errors have been dis-
played the display returns to ON. To erase stored faults,
hold the fault recall button until the display starts flashing,
then release.
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
CLEARANCES AND ACCESSIBILITY
POSITION* FRONT SIDES REAR TOP FLUE FLOOR
Upflow 3" 0" 0" 1" 0" C
Horizontal Alcove 6" 0" 4" 0" C
C = If placed on combustible floor, floor MUST be wood only.
DM97C MINIMUM CLEARANCES TO COMBUSTIBLE MATERIALS
(INCHES)
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
Counterflow 0" 0" 3" NC 0"
Horizontal 6" 0" 3" C 0" 6"
C = If placed on combustible floor, floor MUST be wood only.
NC = For installation on non-combustible floors only. A combustible subbase
must
b
e use
d
f
or insta
ll
ations on com
b
usti
bl
e
fl
ooring.
DC97MC MINIMUM CLEARANCES TO COMBUSTIBLE MATERIALS
(INCHES)
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.
Installationsmustadheretotheclearancesto combustiblema-
terials to which this furnace has been design certified. The
minimumclearance informationforthisfurnace isprovidedon
the unit’s clearance label. These clearances must be perma-
nently maintained. Clearances must also accommodate an
installation’sgas,electrical,anddraintrapanddrainlinecon-
nections. If the alternate combustion air intake or vent/flue
connectionsare usedadditionalclearance mustbeprovidedto
accommodatetheseconnections. RefertoVent/Flue Pipeand
Combustion Air Pipe for details. NOTE: In addition to the
requiredclearancestocombustiblematerials,aminimumof24
inchesserviceclearancemustbe available in front of theunit.
TOP
BOTTOM
SIDE SIDE SIDE
TOP
BOTTOM
Upflow Counterflow Horizontal
THERMOSTAT LOCATION
Thethermostat shouldbeplacedapproximatelyfive feetfrom
the floor on a vibration-free, inside wall in an area having
good air circulation. Do not install the thermostat where it
maybeinfluencedbyanyofthefollowing:
• Drafts,ordeadspotsbehinddoors,incorners,orunder
cabinets.
• Hot or cold air from registers.
• Radiant heat from the sun.
• Light fixtures or other appliances.
• Radiantheatfrom a fireplace.
• Concealedhotorcoldwaterpipes,orchimneys.
• Unconditionedareasbehindthethermostat,suchasan
outsidewall.
Consulttheinstructions packaged with the thermostat for
mountinginstructionsandfurther precautions.
Combustion & Ventilation Air Requirements
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
PRODUCT DESIGN

20
Improved construction and additional insulation in buildings
havereducedheatlossbyreducing air infiltration and escape
around doors and windows. These changes have helped in
reducing heating/cooling costs but have created a problem
supplyingcombustionandventilation airforgasfiredandother
fuel burning appliances. Appliances that pull air out of the
house(clothesdryers,exhaustfans,fireplaces,etc.)increase
the problem by starving appliances for air.
House depressurization can cause back drafting or improper
combustionof gas-fired appliances, thereby exposingbuilding
occupantstogascombustionproducts 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
adequatesupplyofcombustionandventilationairfortheother
appliances. Refer to the latest edition of the National Fuel
Gas Code NFPA 54/ANSI Z223.1 or CAN/CSA B149 Installation
Codes or applicable provisions of the local building codes for
determining the combustion air requirements for the appli-
ances.
Mosthomeswillrequireoutsideairbesuppliedtothefurnace
area by means of ventilation grilles or ducts connecting di-
rectly to the outdoors or spaces open to the outdoors such as
atticsorcrawlspaces.
Installation Positions
DM97MC models may be installed up flow or horizontally
with left or right side down. DC97MC models may be in-
stalleddownflow or horizontally with left orright side down.
Do not install any furnace on its back.
Horizontal Installations
1. Horizontal installations require 5.5" under the furnace
to accommodate the drain trap.
2. Horizontal furnaces must be installed with ¾” slope
from back to front to permit condensate flow towards
the front of the furnace.
When installing a DM97MC horizontally with the left side
down, there are two options for connecting the vent pipe to
the furnace.
1. Venting may be connected to the furnace vent pipe fit-
ting on the original top (now the end) of the furnace
2. The internalventpipe and elbowmay beremoved from
the furnace to permit the vent to exit the top (original
side) of the furnace. If this option is used, an RF000142
Vent-Drain coupling must be used to keep condensate
from collecting in the inducer assembly.
Refer to the following instructions and illustration.
Insert flange. Cut 2 ½” long.
R 000142F
Horizontal Installation
CUTHERE
Vent/Flue Pipe Cuts
1. Remove screws from vent flange.
2. Remove internal elbow and vent pipe.
3. Cut pipe 2 1/2” from flange.
4. Remove cabinet plug adjacent to inducer outlet and in-
stall an original cabinet vent hole.
5. Install RF000142 coupling on inducer outlet.
6. Install flanged vent section removed in step 2 & secure
with clamps.
7. Secure flange to cabinet using screws removed in step
1.
PRODUCT DESIGN