Amana GDH8 User manual

5151 San Felipe Suite 500 • Houston, TX 77056
www.goodmanmfg.com • www.amana-hac.com
©2011 - 2014 Goodman Manufacturing Company, L.P.
ATTENTION INSTALLING PERSONNEL
RECOGNIZE THIS SYMBOL AS A SAFETY PRECAUTION.
Installer: Affix all manuals adjacent to the unit.
Thesefurnacescomplywithrequirementsem-
bodiedintheAmericanNationalStandard /Na-
tional Standard of CanadaANSI Z21.47·CSA-
2.3GasFiredCentralFurnaces.
As a professional installer, you have an obligation to know the product better than the customer.
This includes all safety precautions and related items.
Priorto actual installation, thoroughly familiarize yourselfwith 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.
The precautions listed in this Installation Manual are intended as supplemental to existing practices.
However, if there is a direct conflict between existing practices and the content of this manual,
the precautions listed here take precedence.
NOTE: Please contact your distributor or our website listed below
for the applicable Specification Sheet referred to in this manual.
G OODMAN WILL NOT BE RESPONSIBLE FOR ANY INJURY OR PROPERTY
DAMAGE ARISING FROM IMPROPER SERVICE OR SERVICE PROCEDURES .
I
F YOU INSTALL OR PERFORM SERVICE ON THIS UNIT , YOU ASSUME
RESPONSIBILITY FOR ANY PERSONAL INJURY OR PROPERTY DAMAGE
WHICH MAY RESULT . M ANY JURISDICTIONS REQUIRE A LICENSE TO
INSTALL OR SERVICE HEATING AND AIR CONDITIONING EQUIPMENT .
WARNING
IO-446A
3/2014
INSTALLATION INSTRUCTIONS FOR *M(H,S)8 / GD(H,S)8 / GHS8 / GME8
ADS(H,S)8 / AMEH8 GAS FURNACE
(CATEGORYI)
is a registered trademark of Maytag Corporation or its related companies and is used under license. All rights reserved.

2
Table of Contents
SAFETY CONSIDERATIONS ............................................................................................................................ 5
ADDITIONAL SAFETY CONSIDERATIONS ...................................................................................................... 6
SHIPPING INSPECTION ........................................................................................................................... 6
ELECTROSTATIC DISCHARGE (ESD)PRECAUTIONS ..................................................................................... 6
TOTHE INSTALLER .............................................................................................................................. 7
PRODUCT APPLICATION ............................................................................................................................... 7
REMOVED WARRANTY SECTION.............................................................................................. 7
LOCATION REQUIREMENTS AND CONSIDERATIONS ................................................................................................ 8
CLEARANCES AND ACCESSIBILITY ............................................................................................................ 9
INSTALLATION POSITIONS ...................................................................................................................... 9
HORIZONTAL INSTALLATION .................................................................................................................. 10
FURNACE SUSPENSION ........................................................................................................................ 10
EXISTING FURNACE REMOVAL .............................................................................................................. 10
THERMOSTAT LOCATION ...................................................................................................................... 10
COMBUSTION AND VENTILATION AIR REQUIREMENTS...........................................................................................11
CATEGORY IVENTING (VERTICAL VENTING) .....................................................................................................11
EXTERIOR MASONRY CHIMNEYS (CATEGORY IFURNACES ONLY)......................................................................... 12
CHECKLIST SUMMARY ........................................................................................................................ 13
CHECK 1 -PROPER CHIMNEY TERMINATION. ............................................................................................. 13
CHECK 2-ANY SOLID OR LIQUID FUEL APPLIANCES VENTED INTO THIS CHIMNEY CHANNEL ...................................... 14
CHECK 3- CHIMNEY CROWN CONDITION................................................................................................. 14
CHECK 4- DEBRIS IN CLEANOUT .......................................................................................................... 14
CHECK 5- LINER CONDITION................................................................................................................ 14
CHECK 6- DILUTION AIR. ................................................................................................................... 15
CHECK 7- COMPLETE THE INSTALLATION. ............................................................................................... 15
FIX 1- LINER TERMINATION ................................................................................................................. 15
FIX 2-CHANGE VENTING ARRANGEMENTS ............................................................................................... 15
FIX 3-REBUILD THE CROWN ............................................................................................................... 15
FIX 4- RELINING .............................................................................................................................. 16
ELECTRICAL CONNECTIONS ........................................................................................................................ 16
WIRING HARNESS .............................................................................................................................. 17
115VOLT LINE CONNECTIONS ............................................................................................................. 17
FOSSIL FUEL APPLICATIONS ................................................................................................................ 17
JUNCTION BOX RELOCATION ................................................................................................................ 17
24VOLT THERMOSTAT WIRING ............................................................................................................ 18
GME8/AMEH8FURNACE WITH 2-STAGE CONDENSER FIELD WIRING ........................................................ 18
SETTING THE HEAT ANTICIPATOR ........................................................................................................... 18
115VOLT LINE CONNECTION OF ACCESSORIES ........................................................................................ 19
ELECTRONICAIR CLEANER .................................................................................................................. 19
24VAC HUMIDIFIER .......................................................................................................................... 19
GAS SUPPLY AND PIPING ........................................................................................................................... 19
HIGH ALTITUDE DERATE ...................................................................................................................... 20
PROPANE GAS CONVERSION ................................................................................................................ 20
GAS PIPING CONNECTIONS .................................................................................................................. 20
UPFLOW INSTALLATIONS ..................................................................................................................... 21
COUNTERFLOW INSTALLATIONS.............................................................................................................. 21
GAS PIPING CHECKS ......................................................................................................................... 21

3
Table of Contents
PROPANE GAS TANKS AND PIPING ......................................................................................................... 22
CIRCULATING AIR AND FILTERS .................................................................................................................... 22
DUCTWORK -AIR FLOW...................................................................................................................... 22
CHECKING DUCT STATIC ..................................................................................................................... 23
FILTERS -READ THIS SECTION BEFORE INSTALLING THE RETURN AIR DUCTWORK ............................................ 23
UPRIGHT INSTALLATIONS ..................................................................................................................... 23
CIRCULATION AIR FILTERS ................................................................................................................... 24
HORIZONTAL INSTALLATIONS ................................................................................................................ 24
SEQUENCE OF OPERATION (INTEGRATED IGNITION CONTROL) ................................................................................ 24
POWER UP...................................................................................................................................... 24
HEATING MODE ................................................................................................................................. 24
(MODE DIP SWITCH IS SET TO “1 STG”POSITION).................................................................................. 24
(MODE DIPSWITCH IS SET TO “2 STG” POSITION) ................................................................................. 24
COOLING MODE ................................................................................................................................25
FAN ONLY MODE .............................................................................................................................. 25
START-UP PROCEDUREANDADJUSTMENT ....................................................................................................... 25
FURNACE OPERATION .......................................................................................................................... 25
FURNACE START-UP ........................................................................................................................... 25
FURNACE SHUTDOWN ......................................................................................................................... 26
GAS SUPPLY PRESSURE MEASUREMENT .................................................................................................. 26
GAS MANIFOLD PRESSURE MEASUREMENT AND ADJUSTMENT ....................................................................... 28
GAS INPUT RATE MEASUREMENT (NATURAL GAS ONLY) ............................................................................ 29
TEMPERATURE RISE ........................................................................................................................... 30
CIRCULATOR BLOWER SPEED ADJUSTMENT ............................................................................................. 30
CIRCULATOR BLOWER FAN TIMING ADJUSTMENT ...................................................................................... 30
SETTING FURNACE OPERATING MODE (GDH8,GME8, *MH8,AMEH8 AND ADSH8 MODELS ONLY) ............. 31
OPERATIONAL CHECKS .............................................................................................................................. 31
BURNER FLAME ................................................................................................................................31
AUXILIARY LIMIT CONTROL ................................................................................................................. 31
SAFETY CIRCUIT DESCRIPTION .................................................................................................................... 32
GENERAL ......................................................................................................................................... 32
INTEGRATED CONTROL MODULE ............................................................................................................. 32
PRIMARY LIMIT ................................................................................................................................32
AUXILIARY LIMIT ............................................................................................................................... 32
ROLLOUT LIMITS .............................................................................................................................. 32
PRESSURE SWITCHES ......................................................................................................................... 32
FLAME SENSOR ................................................................................................................................32
TROUBLESHOOTING ................................................................................................................................... 32
ELECTROSTATIC DISCHARGE (ESD)PRECAUTIONS ................................................................................... 32
DIAGNOSTIC CHART........................................................................................................................... 32
FAULT RECALL ................................................................................................................................32
RESETTING FROM LOCKOUT ................................................................................................................ 33

4
Table of Contents
MAINTENANCE ......................................................................................................................................... 33
ANNUAL INSPECTION ........................................................................................................................... 33
FILTERS .......................................................................................................................................... 33
FILTER MAINTENANCE ......................................................................................................................... 33
FILTER REMOVAL .............................................................................................................................. 33
INDUCED DRAFT AND CIRCULATOR BLOWER MOTORS ................................................................................. 33
FLAME SENSOR (QUALIFIED SERVICER ONLY) .......................................................................................... 34
IGNITER (QUALIFIED SERVICER ONLY) ..................................................................................................... 34
BURNERS ......................................................................................................................................... 34
CLEANING (QUALIFIED SERVICER ONLY) ........................................................................................................ 34
BEFORE LEAVING AN INSTALLATION ............................................................................................................... 34
REPAIR AND REPLACEMENT PARTS .............................................................................................................. 34
COMPONENT ID................................................................................................................................ 35
TROUBLESHOOTING CHART .................................................................................................................. 36
APPENDIX ............................................................................................................................................... 37
TROUBLESHOOTING CHART .................................................................................................................. 37
TROUBLESHOOTING CHART .................................................................................................................. 37
TROUBLESHOOTING CHART .................................................................................................................. 38
BLOWER PERFORMANCE DATA ............................................................................................................. 39
*M(H/S)8................................................................................................................................. 39
GDS8 / ADSS8 & GHS8......................................................................................................... 40
BLOWER PERFORMANCE DATA ............................................................................................................. 41
GDH8 / ADSH8....................................................................................................................... 41
BLOWER PERFORMANCE DATA ............................................................................................................. 42
GME8 ..................................................................................................................................... 42
BLOWER PERFORMANCE DATA ............................................................................................................. 43
AMEH8................................................................................................................................... 43
*(M, D, H)S8 /ADSS8 WIRING DIAGRAM .......................................................................................... 44
GME8 / AMEH8 WIRING DIAGRAM WHITE RODGERS GAS VALVE .................................................... 45
GME8 / AMEH8 WIRING DIAGRAM HONEYWELLGAS VALVE ........................................................... 46
*(M,D)H8 / ADSH8 WIRING DIAGRAM WHITE RODGERS GAS VALVE................................................ 47
*(M,D)H8 / ADSH8 WIRING DIAGRAM HONEYWELLGAS VALVE ....................................................... 48

5
G OODMAN
DAMAGE ARISING FROM IMPROPER SERVICE OR SERVICE PROCEDURES .
I
F YOU INSTALL OR PERFORM SERVICE ON THIS UNIT , YOU ASSUME
RESPONSIBILITY FOR ANY PERSONAL INJURY OR PROPERTY DAMAGE
WHICH MAY RESULT . M ANY JURISDICTIONS REQUIRE A LICENSE TO
INSTALL OR SERVICE HEATING AND AIR CONDITIONING EQUIPMENT .
WILL NOT BE RESPONSIBLE FOR ANY INJURY OR PROPERTY
WARNING
S AFETY C ONSIDERATIONS
Adhereto the followingwarningsand cautions wheninstalling,
adjusting,altering,servicing, or operating the furnace. To en-
sure proper installation and operation, thoroughly read this
manualforspecificspertainingtotheinstallationand applica-
tion of this product.
This furnace is manufactured for use with natural gas. It may
befield convertedtooperate on L.P. gas byusingthe appropri-
ateL.P. conversionkitlistedinthe PROPANE GAS/HIGH AL-
TITUDE INSTALLATIONS section ofthis manual
Install this furnace only in a location and position as specified
inLOCATION REQUIREMENTS & CONSIDERATIONS sec-
tion and INSTALLATIONPOSITIONSsectionofthismanual.
Provideadequate combustionand ventilationairto thefurnace
as specified in COMBUSTION & VENTILATION AIR RE-
QUIREMENTS section of this manual.
Combustion products must be discharged to the outdoors.
Connectthisfurnacetoanapprovedventsystemonly,asspeci-
fiedinVENT/FLUE PIPE & COMBUSTION AIR PIPE section
of this manual.
Never test for gas leaks with an open flame. Use a commer-
cially available soap solution made specifically for the detec-
tion of leaks to check all connections, as specified in GAS
SUPPLYAND PIPING section of this manual.
Alwaysinstallafurnaceto operatewithinthefurnace’sintended
temperature-riserangewith a duct system which has external
staticpressurewithintheallowablerange,as specified on the
furnacerating plate and OPERATIONAL CHECKS sectionof
these instructions.
When a furnace is installed so that supply ducts carry air cir-
culated by the furnace to areas outside the space containing
the furnace, the return air shall also be handled by duct(s)
sealedto thefurnacecasingandterminating outsidethespace
containingthe furnace.
Agas-fired furnace for installationinaresidential garage must
beinstalledasspecifiedinthe LOCATION REQUIREMENTS
ANDCONSIDERATIONS section ofthismanual.
Thisfurnacemaybe used as a construction site heater only if
certain conditions are met. These conditions are listed in the
PRODUCTAPPLICATIONsectionof this manual.
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

6
CARBON MONOXIDE POISONING HAZARD
-
Special Warning for Installation of Furnace or Air Handling Units in
Enclosed Areas such as Garages, Utility Rooms or Parking Areas
Carbon monoxide producing devices (such as an automobile, space
heater, gas water heater, etc.) should not be operated in enclosed areas
such as unventilated garages, utility rooms or parking areas because of
the danger of carbon monoxide (CO) poisoning resulting from the exhaust
emissions. If a furnace or air handler is installed in an enclosed area such
as a garage, utility room or parking area and a carbon monoxide producing
device is operated therein, there must be adequate, direct outside
ventilation.
This ventilation is necessary to avoid the danger of CO poisoning which
can occur if a carbon monoxide producing device continues to operate in
the enclosed area. Carbon monoxide emissions can be (re)circulated
throughout the structure if the furnace or air handler is operating in any
mode.
CO can cause serious illness including permanent brain damage or death.
B10259-216
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
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
T O PREVENT PERSONAL INJURY OR DEATH DUE TO ASPHYXIATION , THIS
FURNACE MUST BE C ATEGORY I VENTED . D O NOT VENT USING
C
ATEGORY III VENTING .
P
ROVISIONS MUST BE MADE FOR VENTING COMBUSTION PRODUCTS
OUTDOORS THROUGH A PROPER VENTING SYSTEM . T HE LENGTH OF
FLUE PIPE COULD BE A LIMITING FACTOR IN LOCATING THE FURNACE .
WARNING
ADDITIONALSAFETYCONSIDERATIONS
• Thisfurnaceis approved for Category IVentingonly.
• Provisions must be made for venting combustion
products outdoors through a proper venting system.
The length of flue pipe could be a limiting factor in
locatingthefurnace.
SHIPPINGINSPECTION
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. Ifdamageisfound,arequestforinspectionbycarrier’s
agent must be made in writing immediately.
Thefurnacemust be carefully inspected on arrivalfordamage
and bolts or screws which may have come loose in transit. In
theeventof damage the consignee should:
1. Makeanotationondeliveryreceiptofanyvisible damage
toshipmentor container.
2. Notifycarrier promptly and request an inspection.
3. Withconcealeddamage, carriermustbenotifiedassoon
aspossible - preferably within five days.
4. Filetheclaimwiththefollowingsupportdocumentswithin
a nine month statute of limitations.
• Original or certified copy of the Bill of Lading, or
indemnitybond.
• Originalpaidfreightbillorindemnityinlieuthereof.
• Originalor certified copy oftheinvoice,showing trade
andotherdiscountsor reductions.
• Copy of the inspection report issued by carrier’s
representativeatthetimedamageisreportedtocarrier.
Thecarrierisresponsible formakingpromptinspectionof dam-
ageandforathoroughinvestigationofeach claim.The distribu-
torormanufacturerwillnotacceptclaimsfromdealersfortrans-
portationdamage.
Keep this literature in a safe place for future reference.
ELECTROSTATICDISCHARGE (ESD)PRECAUTIONS
NOTE: Dischargebody’s staticelectricitybeforetouching unit.
Anelectrostaticdischarge can adversely affect electrical com-
ponents.
Use the following precautions during furnace installation and
servicing to protect the integrated control module from dam-
age. Byputtingthefurnace,thecontrol,andthepersonatthe
sameelectrostatic potential, these stepswillhelp avoid expos-
ing the integrated control module to electrostatic discharge.
Thisprocedure is applicabletobothinstalled andnon-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 electrostatic
chargeto ground.

7
• The vent system is permanently installed per these
installation instructions.
• Aroomthermostatisusedtocontrolthefurnace. Fixed
jumpersthat provide continuousheatingCANNOT be
used.
• Returnairductsareprovidedandsealedtothefurnace.
• A return air temperature range between 60ºF (16ºC)
and80ºF(27ºC)ismaintained.
• Air filters are installed in the system and maintained
during construction, replaced as appropriate during
construction,and uponcompletionofconstruction are
replaced.
• The input rate and temperature rise are set per the
furnace ratingplate.
• 100% outside air is provided for combustion air
requirementsduringconstruction.Temporary ducting
can be used.
NOTE: Do not connect the temporary duct directly to
the furnace. The duct must be sized according to the
instructions under Combustion and Ventilation Air
Requirements,Section5.3.3.
•The furnace heat exchanger, components, duct
system,airfiltersand evaporator coils are thoroughly
cleanedfollowingfinalconstruction clean up.
• Allfurnaceoperatingconditions(includingignition,input
rate, temperature rise and venting) are verified
according to these installation instructions.
NOTE:TheCommonwealth ofMassachusetts requiresthatthe
followingadditionalrequirementsmustalsobemet:
• Gasfurnaces must be installedbya licensed plumber
orgas fitter.
• AT-handle gas cock must be used.
• Ifthe unit is to beinstalledinanattic, the passageway
to and the service area around the unit must have
flooring.
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
To ensure proper furnace operation, install, operate and
maintain the furnace in accordance with these installa-
tion and operation instructions, all local building codes
and ordinances. In their absence, follow the latest edition of
the National Fuel Gas Code (NFPA54/ANSI Z223.1), and/or
CAN/CSA B149 Installation Codes, local plumbing or waste
watercodes,andotherapplicablecodes.
2. Firmly touch a clean, unpainted, metal surface of the
furnaces near the control. Any tools held in a person’s
handduring grounding willbedischarged.
3. Service integrated control module or connecting wiring
following the discharge process in step 2. Use caution
nottorechargeyourbodywithstaticelectricity;(i.e.,do
notmoveorshuffleyourfeet, do not touch ungrounded
objects,etc.). Ifyoucomeincontactwithanungrounded
object,repeatstep 2 before 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. Return any old or
new controls to their containers before touching any
ungroundedobject.
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-
tricalconnections, circulating air temperaturerise,minimum or
maximum CFM, and motor speed connections, and venting.
Thesefurnaces are designed forCategoryIventing only.
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
Thisfurnace is primarilydesignedfor residential home-heating
applications. It is NOT designed or certified for use in mobile
homes,trailersorrecreationalvehicles. Neitherisitdesigned
or certified for outdoor applications. The furnace must be in-
stalled indoors (i.e., attic space, crawl space, or garage area
providedthe garage area is enclosedwithanoperating door).
This furnace can be used in the following non-industrial com-
mercialapplications:
Schools,Officebuildings,Churches,Retailstores,
Nursinghomes,Hotels/motels,Commonorofficeareas
In such applications , the furnace must be installed with the
followingstipulations:
• It must be installed per the installation instructions
providedandper 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
freeair delivery application.
• It must not be used as a “make-up” air unit.
• All other warranty exclusions and restrictions apply.
Thisfurnacemay be used as a construction site heater ONLY
ifthefollowingconditionsaremet:

8
Acopy of theNationalFuelGas Code (NFPA54/ANSI Z223.1)
canbeobtainedfromanyofthefollowing:
American National Standards Institute
1430Broadway
New York, NY 10018
National Fire Protection Association
1 Batterymarch Park
Quincy, MA 02269
CSA International
8501 East Pleasant Valley
Cleveland,OH44131
A copy of the CAN/CSA B149 Installation Codes can also be
obtainedfrom: CSA International
178RexdaleBoulevard
Etobicoke,Ontario,CanadaM9W1R3
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
orinaccordancewith “ASHRAEGuide”or“ManualJ-Load Cal-
culations” published by the Air Conditioning Contractors of
America.
IntheUSA, this furnace MUST beinstalledinaccordance with
thelatestedition of theANSI Z223.1 booklet entitled “National
Fuel Gas Code” (NFPA54), and the requirements or codes of
thelocal utility orotherauthority having jurisdiction.InCanada,
this furnace must be installed in accordance with the current
CAN/CGA-B149.1&2GasInstallationCodes,localplumbing
or waste water codes and other applicable codes. Additional
helpful publications available from the NFPAare, NFPA90A-
InstallationofAirConditioningandVentilatingSystemandNFPA
90B - WarmAir Heating andAir Conditioning System.
AllventingshallbeinaccordancewithPART7,VentingofEquip-
ment, of the National Fuel Gas Code, ANSI Z223.1, or appli-
cablelocalbuildingand/or air conditioning codes. These pub-
licationsare available from:
National Fire Protection Association, Inc.
1 Batterymarch Park, Quincy, MA 02269
NOTE: Furnaces with NOx screens meet the California NOx
emission standards and California seasonal efficiency stan-
dards.ANNUALinspections of the furnace anditsvent system
isstronglyrecommended.
L OCATION R EQUIREMENTS AND C ONSIDERATIONS
Your unit model typedetermineswhichinstallationprocedures
must be used. For *MH8, *MS8, and GHS8 models, you must
follow instructions for Horizontal Left, Horizontal Right or Up-
flow installations only. These furnaces are not approved for
Downflowinstallations.
DownflowmodelsGD(H,S) ARENOTAPPROVED FORHORI-
ZONTAL OR UPFLOW INSTALLATIONS. For these models,
use only the instructions for downflow installation only.
T O PREVENT POSSIBLE EQUIPMENT DAMAGE , PROPERTY DAMAGE ,
PERSONAL INJURY OR DEATH , THE FOLLOWING BULLET POINTS MUST BE
OBSERVED WHEN INSTALLING THIS UNIT .
WARNING
Follow the instructions listed below when selecting a furnace
location. Refer also to the guidelines provided in Section V,
CombustionandVentilationAir Requirements.
• Centrally locate the furnace with respect to the
proposed or existing air distribution system.
• Ensure the temperature of the return air entering the
furnaceis between 55°F and 100°Fwhenthefurnace
is heating.
• If the furnace is installed in an application where the
typical operating sound level of a furnace is deemed
objectionable, an optional sound reduction kit is
available.Consultyourlocaldistributorformoredetails.
• Provisions must be made for venting combustion
products outdoors through a proper venting system.
The length of flue pipe could be a limiting factor in
locatingthefurnace.
• Ensure adequate combustion air is available for the
furnace. Improper or insufficient combustion air can
exposebuildingoccupantstogascombustionproducts
thatcould include carbon monoxide. RefertoSection
V, Combustion and VentilationAir Requirements.
• The furnace must be level. If the furnace is to be set
onafloorthatmaybecomewetordamp at times, the
furnace should be supported above the floor on a
concretebasesizedapproximately1-1/2" larger than
thebaseofthefurnace.
• Ensureupflowor horizontal furnaces are notinstalled
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
installthefurnace wherethecombustionairisexposed
tothe following substances:
chlorinated waxes or cleaners
chlorine-based swimming pool chemicals
water softening chemicals
deicing salts or chemicals
carbon tetrachloride
halogen type refrigerants
cleaning solutions (such as perchloroethylene)
printing inks
paint removers
varnishes
hydrochloric acid
cements and glues
antistatic fabric softeners for clothes dryers
and masonry acid washing materials

9
Top - 1"
Side
Clearance - 1"
Back - 0"
Front Clearance - 3"
V
ent Pipe Clearance to Combustibles-
6" using Single Wall Connector or 1"
using B-1 vent.
• Adequatecombustion/ventilation airmust besupplied
to the closet.
• Furnacemustbe completelysealedtofloororbase.
Combustion/ ventilation air supply pipes must
terminate 12" from top of closet and 12" from floor of
closet. DO NOT remove solid base plate for side
return.
• Return air ducts must be completely sealed to the
furnaceandterminateoutside theenclosure surfaces.
CLEARANCESANDACCESSIBILITY
Unobstructed front clearance of 24" for servicing is recom-
mended.
TOP
B1-VENT SINGLE (PLENUM)
1" 6" 1" 3" 0" 1"
VENT SIDES FRONT BACK
Top clearance for horizontal configuration - 1"
INSTALLATIONPOSITIONS
An upflow furnace may be installed in an upright position or
horizontal on either the left or right side panel. Do not install
this furnaceon itsback. Forvertically installed upflowfurnaces,
return air ductwork may be attached to the side panel(s) and/
or basepan. For horizontally installed upflow furnaces, return
airductwork mustbeattachedto thebasepan.Forcounterflow
furnaces, return ductwork must be attached to the top end of
theblower compartment.
NOTE: Ductwork must never be attached to the back of the
furnace.
• Ifthe furnace is usedinconnectionwith a cooling unit,
install the furnace upstream or in parallel with the
cooling unit coil. Premature heat exchanger failure
willresultifthecoolingunitcoilisplacedaheadofthe
furnace.
For vertical (upflow or downflow) applications, the
minimum cooling coil width shall not be less than
furnace width minus 1”. Additionally, a coil installed
aboveanupflowfurnaceorunderacounterflowfurnace
may be the same width as the furnace or may be one
sizelarger than the furnace. Example:a“C” width coil
may be installed with a “B” width furnace.
Forupflowapplications, thefrontofthecoilandfurnace
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
damageby vehicles.
• If the furnace is installed horizontally, the furnace
access doors must be vertical so that the burners fire
horizontally into the heat exchanger. Do not install
theunitwiththe accessdoors onthe“up/top”or“down/
bottom”sideofthefurnace.
• Do not connect this furnace to a chimney flue that
serves a separate appliance designed to burn solid
fuel.
• For counterflow installations, the air conditioning coil
must be downstream from the heat exchanger of the
furnace.
•Counterflowinstallationoveranoncombustiblefloor.
Before setting the furnace over the plenum opening,
ensurethesurface around the opening is smooth and
level.Atightseal shouldbemade betweenthefurnace
base and floor by using a silicon rubber caulking
compoundorcement grout.
• Counterflow installation over a combustible floor. If
installation over a combustible floor becomes
necessary, use an accessory subbase (see
SpecificationSheetapplicabletoyourmodelfordetails).
Aspecial accessorysubbasemustbe usedforupright
counterflow unit installations over any combustible
material including wood. Follow the instructions with
thesubbaseforproperinstallations.Donotinstallthe
furnacedirectly oncarpeting,tile, orothercombustible
materialotherthanwoodflooring.(NOTE:Thesubbase
willnot berequiredif anairconditioning coilisinstalled
betweenthe supplyairopening onthefurnace andthe
floor.

10
HORIZONTALINSTALLATION
For
horizontal installations,
insert the
#8 x 5/8 screw
from the
literature package.
Line contact to framing is permitted when installed in the hori-
zontal configuration. Line contact is defined as the portion of
the cabinet that is formed by the intersection of the top and
side. ACCESSIBILITY CLEARANCE, WHERE GREATER,
SHOULDTAKE PRECEDENCEOVERMINIMUM FIREPRO-
TECTIONCLEARANCE. Agas-fired furnace forinstallationin
aresidentialgaragemustbeinstalled sothat theignition source
and burners are located not less than eighteen inches (18")
abovethefloorandisprotectedor located to prevent physical
damage by vehicles. A gas furnace must not be installed di-
rectly on carpeting, tile, or other combustible materials other
thanwood flooring.
FURNACESUSPENSION
Ifsuspendingthefurnacefromraftersorjoist,use3/8" threaded
rod and 2”x2”x3/8” angle iron as shown below. The length of
rod will depend on the application and the clearances neces-
sary.
Suspended Furnace
EXISTING FURNACEREMOVAL
NOTE: When an existing furnace is removed from a venting
system serving other appliances, the venting system may be
toolargetoproperly vent the remaining attached appliances.
The following vent testing procedure is reproduced from the
American National Standard/National Standard of Canada
for Gas-Fired Central Furnaces ANSI Z21.47-Latest Edi-
tion, CSA-2.3-Latest Edition Section 1.23.1. The following
steps shall be followed with each appliance connected to the
ventingsystem placedinoperation, while anyotherappliances
connected to the venting system are not in operation:
a. Seal any unused openings in the venting system;
b. Inspect the venting system for proper size and
horizontalpitch,as required by the National Fuel Gas
Code,ANSIZ223.1or the CAN/CSAB149 Installation
Codesandthese instructions. Determine that thereis
noblockageorrestriction,leakage,corrosionandother
deficiencieswhichcouldcauseanunsafecondition;
c. In so far as practical, close all building doors and
windows and all doors between the space in which
theappliance(s)connectedto the venting system are
located and other spaces of the building. Turn on
clothes dryers and any appliance not connected to
the venting system. Turn on any exhaust fans, such
asrange hoods and bathroomexhausts,so they shall
operateatmaximumspeed. Donotoperateasummer
exhaustfan.Close fireplace dampers;
d. Follow the lighting instructions. Place the appliance
being inspected in operation. Adjust thermostat so
applianceshalloperatecontinuously;
e. Testfor drafthood equipped appliance spillage at the
drafthoodreliefopeningafter 5minutesofmainburner
operation. Use the flame of a match or candle;
f. After it has been determined that each appliance
connectedtothe venting system properly ventswhen
tested as outlined above, return doors, windows,
exhaust fans, fireplace dampers and any other gas
burningapplianceto their previous conditions of use;
g. Ifimproperventingisobserved duringanyoftheabove
tests,the common ventingsystemmustbe corrected.
Corrections must be in accordance with the latest edition of
theNationalFuelGasCodeNFPA54/ANSIZ223.1and/orCAN/
CSAB149Installation Codes.
Ifresizing is required onanyportionof the venting system,use
the appropriate table inAppendix G in the latest edition of the
National Fuel Gas CodeANSI Z223.1 and/or CAN/CSAB149
InstallationCodes.
THERMOSTATLOCATION
In an area having good air circulation, locate the thermostat
aboutfive feethigh onavibration-freeinsidewall. Do notinstall
thethermostat where it maybeinfluencedby any of thefollow-
ing:
• Drafts,ordeadspotsbehinddoors,incorners,orunder
cabinets.
• Hot or cold air from registers.

11
• Radiantheatfromthesun.
• Lightfixturesorotherappliances.
• Radiantheatfrom a fireplace.
• Concealed hot or cold water pipes, or chimneys.
• Unconditioned areas behind the thermostat, such as
anoutside wall.
HOT
COLD
Thermostat Influences
Consulttheinstructionspackagedwiththethermostatformount-
inginstructionsandfurther precautions.
C OMBUSTION AND 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
reducedheatlossbyreducingair infiltrationand escapearound
doors and windows. These changes have helped in reducing
heating/cooling costs but have created a problem supplying
combustionand ventilation airforgas fired andotherfuelburn-
ingappliances. Appliancesthatpullairoutof thehouse (clothes
dryers,exhaustfans,fireplaces,etc.) increase the problem by
starvingappliancesforair.
House depressurization can cause back drafting or improper
combustionof gas-fired appliances, therebyexposingbuilding
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
adequatesupply of combustion andventilationair for the other
appliances. Referto the latest editionofthe National Fuel Gas
Code NFPA 54/ANSI Z223.1 or CAN/CSA B149 Installation
Codes or applicable provisions of the local building codes for
determiningthecombustionairrequirementsfortheappliances.
This furnace must use indoor air for combustion. It cannot be
installed as a direct vent (i.e., sealed combustion) furnace.
Most homes will require outside air be supplied to the furnace
areaby meansofventilationgrilles orductsconnecting directly
to the outdoors or spaces open to the outdoors such as attics
or crawl spaces.
C ATEGORY I V ENTING (V ERTICAL V ENTING )
T O PREVENT POSSIBLE PERSONAL INJURY OR DEATH DUE TO
ASPHYXIATION , THIS FURNACE MUST BE C ATEGORY I VENTED . D O NOT
VENT USING C ATEGORY III VENTING .
WARNING
Category I Venting is venting at a non-positive pressure. A
furnaceventedasCategoryIisconsideredafan-assisted ap-
pliance and the vent system does not have to be “gas tight.”
NOTE: Single stage gas furnaces with induced draft blowers
drawproductsof combustion through a heat exchanger allow-
ing,insomeinstances, common venting with natural draft ap-
pliances(i.e. water heaters).Allinstallationsmustbevented in
accordancewithNationalFuelGasCodeNFPA54/ANSIZ223.1
-latest edition. In Canada, the furnaces must beventedinac-
cordance with the National Standard of Canada, CAN/CSA
B149.1andCAN/CSAB149.2-latesteditionsandamendments.
NOTE: Masonry vent kit (MVK-01 and MVK-02) is to only be
used on interior masonry chimneys or qualifying exterior
masonry chimney applications identified in the MVK kit
installationinstructions.To ensure safe and reliable operation,
use only the kit listed for your model.
Kit Input KBTU Range Limit Setting
MVK-01 40-100 250°F
MVK-02 120-140 290°F
Note: This kit is for use on Amana®brand and Goodman®brand80%AFUE,
33” tall “H” and “S” model furnaces installed in the upflow position only.
NOTE: The vertical height of the Category I venting system
mustbe at least asgreatas the horizontal lengthoftheventing
system.
T O PREVENT POSSIBLE PERSONAL INJURY OR DEATH DUE TO
ASPHYXIATION , COMMON VENTING WITH OTHER MANUFACTURER ’ S
INDUCED DRAFT APPLIANCES IS NOT ALLOWED .
WARNING

12
Theminimumventdiameterfor the Category I venting system
is as shown:
UPFLOW COUNTERFLOW
40 4 Inch 4 Inch
60 4 Inch 4 Inch
80 4 Inch 4 Inch
100 5 Inch 5 Inch
120 5 Inch N/A
140 5 Inch N/A
MODEL MINIMUM VENT
Undersomeconditions,largervents than those shown above
may be required or allowed. When an existing furnace is re-
moved from a venting system serving other appliances, the
ventingsystem maybetoo largetoproperly venttheremaining
attachedappliances.
Upflow or Horizontal units areshippedwith the induceddraft
blower discharging from the top of the furnace. (“Top” is as
viewedforanupflow installation.) Theinduced draftblowercan
be rotated 90 degrees with the (0270F01119) chimney transi-
tion bottom kit for Category I venting. For horizontal installa-
tions, a four inch single wall pipe can be used to extend the
induced draft blower outlet 1/2” beyond the furnace cabinet.
THISPRODUCTISNOTDESIGNED FORCOUNTERCLOCK-
WISEINDUCED DRAFT BLOWER ROTATION.
Vent the furnace in accordance with the National Fuel Gas
Code NFPA54/ANSI Z223.1 - latest edition. In Canada, vent
thefurnaceinaccordancewiththeNationalStandardofCanada,
CAN/CSAB149.1andCAN/CSAB149.2 -latesteditionsand
amendments.
Venting - Furnace Installed in Horizontal Position
THIS FURNACE IS NOT DESIGN CERTIFIED TO BE HORI-
ZONTALLYVENTEDTHROUGHANEXTERIORSIDE WALL.
Thefollowingdescribes anoptionalventingprocedurewhenthe
furnace is installed in the horizontal left discharge position.
To rotate the induced draft blower clockwise, you will need to
purchaseone(0270F01119)chimney transition bottom kit.
1. Disconnectelectrical power from thefurnace.
2. Disconnect the induced draft blower power leads, flue
pipe,andpressureswitchtubing.
3. Removetheroundcutoutfromtherightsideofthewrapper.
4. Removeandsavethefourscrewsthatfastentheinduced
draft blower to the flue collector box.
5. Removeandsavethethreescrewsthatholdthechimney
assemblytotheinduceddraftblower.
6. Removeandsavethefourscrewsthatfastenthechimney
top to the chimney bottom.
7. Removethechimneytransitionbottomfromthetransition
bottom kit.
8. Install the chimney top with the four screws retained
fromstep 6ontothe newchimneytransition bottomfrom
the transition bottom kit.
9. Remove the induced draft blower and install the new
chimneyassemblytoitusingthethree screws retained
from step 5.
10. Rotatethe induceddraftblower90degreestotheright,
feedthefluepipethroughtheroundcutoutfromtheoutside
of the wrapper, and fit onto the chimney top assembly.
Secure the pipe to the chimney top from the front, top,
and bottom using (3) screws and rotating the induced
draft blower to properly orient the assembly. NOTE: If
the pipe section is less than 18”, then attach it directly
to the chimney top on 3 sides and feed it through the
roundcutoutfromtheinside of the wrapper.
11. Reattach the induced draft blower using the (4) screws
retainedfromstep 3. Ensurethegasketlocatedbetween
the induced draft blower and collector box is rotated
accordingly.
12. Reconnecttheinduceddraftblowerpowerleads.NOTE:
Ifthewires are not long enough, pull extra wire fromthe
wirebundlein the blower compartment.
13. Reconnect the remaining flue pipe, and the pressure
switch tubing. Ensure that all wires and the pressure
switch tubing is at least one inch from the flue pipe, or
anyotherhotsurface.
14. Restorepower tofurnace.
NOTE: In a horizontal installation the air conditioning coil
must be adequately supported by proper brackets and
supports. Inadequatecoilsupportcanresultinfurnacecabinet
distortionandairleakage.
Counterflow units are shipped with the induced draft blower
dischargingfrom the top of the furnace. (“Top” as viewed for a
counterflowinstallation.)
Vent the furnace in accordance with the National Fuel Gas
CodeNFPA54/ANSIZ223.1-latestedition. InCanada,ventthe
furnace in accordance with the national standard of Canada,
CAN/CSA B149.1 and CAN/CSA B149.2- latest editions and
amendments.
N EVER ALLOW THE PRODUCTS OF COMBUSTION , INCLUDING CARBON
MONOXIDE , TO ENTER THE RETURN DUCTWORK OR CIRCULATION AIR
SUPPLY .
WARNING
EXTERIORMASONRYCHIMNEYS (CATEGORYIFURNACESONLY)
Anexteriormasonrychimney is defined as a “Masonry” chim-
ney exposed to the outdoors on one or more sides below the
roof line.” The ability to use a clay lined masonry chimney
dependson aparameternot associatedwithinterior chimneys.
Thisvariableisthegeographiclocationoftheinstallation. Re-
searchershavediscoveredthat thewinter designtemperatures
haveadirect impact on the suitabilityofthistypeof venting. In
most situations, the existing masonry chimneys will require a
properly sized metallic liner.

13
Proper Chimney
Termination?
(Check 1)
Chimney channel
free of solid and
liquid fuel
appliances?
(Check 2)
Change venting
arrangements
(Fix 2)
Crown in good
condition
(Check 3)
Rebuild crown
(Fix 3)
and/or Reline
(Fix 4)
Reline
(Fix 4)
Reline
(Fix 4)
Cleanout free of
debris?
(Check 4)
Liner in good
condition?
(Check 5)
Reline
(Fix 4)
Dilution air
available?
(Check 6)
Complete the
installation.
(Check 7)
CHECK 1 -PROPER CHIMNEY TERMINATION.
A masonry chimney used as a vent for gas fired equipment
mustextend at leastthreefeet above thehighestpointwhere it
passesthrough the roof. It mustextendatleasttwo feet higher
thananyportion of a building within ahorizontaldistanceof10
feet. In addition, the chimney must terminate at least 3 feet
above any forced air inlet located within 10 feet. The chimney
mustextendatleastfivefeetabovethehighestconnectedequip-
mentdrafthood outlet or flue collar.
Ifthechimneydoesnotmeettheseterminationrequirements,
but all other requirements in the checklist can be met, it may
be possible for a mason to extend the chimney. If this will not
be practical, see Fix 1.
P OSSIBILITY OF PROPERTY DAMAGE , PERSONAL INJURY OR DEATH
DAMAGING CONDENSATION CAN OCCUR INSIDE MASONRY CHIMNEYS
WHEN A SINGLE FAN - ASSISTED C ATEGORY I APPLIANCE (80% AFUE
FURNACE ) IS VENTED WITHOUT ADEQUATE DILUTION AIR . D O NOT
CONNECT AN 80% FURNACE TO A MASONRY CHIMNEY UNLESS THE
FURNACE IS COMMON VENTED WITH A DRAFT HOOD EQUIPPED
APPLIANCE OR THE CHIMNEY IS LINED WITH A METAL LINER OR T YPE B
METAL VENT . A LL INSTALLATIONS USING MASONRY CHIMNEYS MUST BE
SIZED IN ACCORDANCE WITH THE APPROPRIATE VENTING TABLES . I F AN
80%
FURNACE IS COMMON VENTED WITH A DRAFT HOOD EQUIPPED
APPLIANCE , THE POTENTIAL FOR CONDENSATION DAMAGE MAY STILL
EXIST WITH EXTREMELY COLD CONDITIONS , LONG VENT CONNECTORS ,
EXTERIOR CHIMNEYS , OR ANY COMBINATION OF THESE CONDITIONS .
T
HE RISK OF CONDENSATION DAMAGE IS BEST AVOIDED BY USING
MASONRY CHIMNEY AS A PATHWAY FOR PROPERLY SIZED METAL LINER
OR T YPE B METAL VENT .
WARNING
Wash
Clay Tile Size: 8" x 8" x12"
(Each x 24" Length)
1/2" to 1"Air Space
Second Floor
First Floor
Attic Floor
Roof Line
Throat
Damper
Breech
Clean Out Fan Assisted
Forced Air
Furnace
Natural Draft
Water Heater
Water Heater
Vent Connector
Basement Floor
F.A.F. Vent
Connector
Typical Multiple Flue Clay Tile Chimney
CHECKLIST SUMMARY
Thischecklist serves as asummaryofthe items tobechecked
beforeventing an80+furnace intoamasonry chimney.Inaddi-
tion,werecommendthataqualifiedservicemanusethischeck-
list to perform a yearly inspection of the furnace venting sys-
tem.
This checklist is only a summary. For detailed information on
each of the procedures mentioned, see the paragraph refer-
enced with each item.
This inspection is based upon a draft topical report, “Masonry
ChimneyInspectionandRelining”,issuedbytheGasResearch
Institute. While not yet finalized, we believe this report repre-
sents the best information on this subject which is currently
available.

14
CHECK 3-CHIMNEY CROWN CONDITION.
Damagefromcondensateusuallyshowsupfirstinthecrown.
Ifany ofthefollowing troublesignsare present, theconditionof
the crown is not satisfactory:
a) Crownleaning
b) Bricks missing
c) Mortarmissing
d) Tilelinercracked
e) No tile liner
f) Salt staining at mortar joints. (White stains, and mortar
becomessandyand/or erodes.)
For problems a, b, or c, see Fix 3. If problems d, e, or f are
present,see Fix 4. IMPORTANT: It maybenecessaryto follow
both Fix 3 and Fix 4.
CHECK 4-DEBRIS INCLEANOUT
Acleanout (dropleg) mustbepresent such thattheupper edge
ofthe cleanoutcoveris atleast12 inchesbelowthe lower edge
of the lowest chimney inlet opening.
A chimney without a cleanout could become partially blocked
by debris. If no cleanout is present, the chimney must be re-
lined (Fix 4). Remove the cleanout cover, and examine the
cleanoutfor debris.If significantamountsofanyof thefollowing
arefound:
• Fueloilresidue
• Bricks
• Mortarorsand
• Pieces of the tile liner
• Rustedpieces ofthemetallicliner -relinethe chimney
(Fix 4).
CHECK 5-LINERCONDITION.
If a metal liner is present, it must be checked. It cannot be
assumed that all existing metal liners are correctly installed
andingoodcondition.
Remove the lowest existing vent connector, and examine the
insideoftheelboworteeatthebaseoftheliner.Asmallamount
of soot may be considered acceptable, provided the installer
vacuums it away. If rusted pieces of the liner have collected
here,themetalliner must be removed and replaced (Fix 4).
Next, gently tap the inside of the liner with a Phillips screw-
driver. If the screwdriver perforates the liner, or if the tapping
does not sound like metal hitting metal, the liner must be re-
movedand replaced (Fix 4).
Rememberthatallappliancesmustbeventedinsidetheliner.
Venting one appliance inside the liner and another appliance
outside the liner is not acceptable.
Next, use a flashlight and small mirror to sight up the liner. B
vent must be supported so as to not come into direct contact
withthechimneywalls or tile liner. If it is not, it can probably be
rehung so as to be acceptable.Athimble or fire stop may be
helpfulhere.
Wall or
Parapet
2' Min.
2' Min. 3' Min.
Chimney
10' or Less
10' or Less
2' Min. 3' Min.
Chimney
Termination 10 Feet Or Less From Ridge, Wall or Parapet
More than 10’
Wall or
Parapet
NOTE: No Height
above parapet
required when distance
from walls or parapet is
more than 10 feet.
Chimney
3’ Min.
More than10’
10’
2” Min.
3’Min.
Chimney
Height above any
roof surface within
10 feet horizontally.
Ridge
Termination More Than 10 Feet From Ridge, Wall or Parapet
CHECK 2-ANYSOLIDORLIQUID FUEL APPLIANCESVENTED
INTOTHISCHIMNEY CHANNEL
Solidfuelappliances include fireplaces, wood stoves,coalfur-
naces,andincinerators.
Liquidfuelappliances include oil furnaces, oil-firedboilersand
oil-firedwater heaters.
Applianceswhichburnpropane(sometimes referred to as LP
(liquefiedpetroleum)) gasareconsideredgas-firedappliances.

15
• Extremelycoldweather
• Longvent connectors
• Masonry chimneys with no air gap between the liner
and the bricks. (In practice, this can be difficult to
detect.)
• Exterior chimneys (The tables in National Fuel Gas
CodeNFPA54/ANSIZ223.1- latest edition andinthe
National Standard of Canada, CAN/CSAB149.1 and
CAN/CSA B149.2 - latest editions and amendments
assumeinteriorchimneys.)
If, in the judgment of the local gas utility, installer, and/or local
codes; one or more of the above factors is likely to present a
problem, the chimney must be relined (Fix 4).
FIX1-LINERTERMINATION
Any cap or roof assembly used with a liner must be approved
by the liner manufacturer for such use. The liner and cap/roof
assembly must then terminate above the roof in accordance
withthemanufacturer’sinstructions.
In some cases, a shorter extension above the roof may be
possible with a liner than would be required with a masonry
chimney.
Forfurtherinformationonrelining,seeFix4.
FIX2-CHANGEVENTINGARRANGEMENTS
Ifthemasonrychimneyhasmore than one channel, it may be
possibletoventthegasappliancesintoone channel and vent
thesolidor liquid fuel appliance(s) into another channel(s).Do
notvent an 80+Furnaceinside of ametallinerwith otherappli-
ancesventedoutsidetheliner.
Alternatively,thehomeownermayagreetodiscontinueuseof
the fireplace (solid fuel appliance). If so, the tile liner must be
cleanedtoremovecreosotebuildup.Thefireplaceopeningmust
thenbepermanently sealed.
If oil-fired appliance(s) are being replaced by gas-fired
appliance(s), the tile liner must first be cleaned to remove the
fueloilresidue.
Ifnoneof the above options is practical, the furnacemayneed
to be vented vertically with a B Vent.
Undersomeconditions,a90%+furnacecouldbeinstalledrather
than an 80% furnace. The 90%+ furnace can be vented hori-
zontallyorverticallythroughPVCpipe.
FIX3-REBUILD THECROWN
If the chimney crown is damaged, a qualified mason must re-
pairitin accordance with nationally recognized building codes
or standards. One such standard which may be referenced is
the Standard for Chimneys, Fireplaces, Vents, and Solid Fuel
BurningAppliances,ANSI/NFPA211.
Flexiblelinersshouldbehungstraightornearlystraight.Ifitis
spiraled in the chimney and in good condition, it should be
rehung. To do this, break the top seal; pull up and cut off the
excess liner length, and refit the top seal. Use caution when
doing this, as the cut edges of flexible liners may be sharp.
The surfaces of the liner must be physically sound. If gaps or
holes are present, the metal liner must be removed and re-
placed (Fix 4). Finally, confirm that the metal liner is the cor-
rect size for the appliances to be installed. Use the GAMA
tablesand rules.
If a metal liner is not present, a clay tile liner must be present,
or the chimney must be lined (Fix 4).
Use a flashlight and small mirror at the cleanout or vent con-
nector to inspect the clay tile liner. If any of the following prob-
lemsarepresent:
• Tilesectionsmisaligned
• Tile sections missing
• Gaps between tile sections
• Signsofcondensatedrainageatthecleanoutor vent
connectors
• Mortarprotrudingfrom between tile sections
• Use of sewer pipe or drainage pipe rather than an
approved fire clay tile reline the chimney (Fix 4).
Next, measure the size of the liner. It may be possible to do
this from the cleanout. The liner must be at least as large as
the minimum size established by the tables in National Fuel
Gas Code NFPA 54/ANSI Z223.1 - latest edition and in the
NationalStandardofCanada,CAN/CSAB149.1andCAN/CSA
B149.2 - latest editions and amendments. If the liner is too
small or too large, then the chimney must be relined (Fix 4).
CHECK6-DILUTION AIR.
If gas-fired appliances are to be vented into a clay tile liner, a
sourceofdilutionairisrequired.
Dilutionaircannot be obtained through:
• Induceddraft appliances
• Naturaldraft appliances withventdampers
Sufficientdilutionaircanordinarilybeobtainedthroughthedraft
hood of a natural draft appliance only if the appliance’s vent
connectordoes notincludea ventdamper. Ifdilutionair willnot
be available, the chimney must be relined (Fix 4).
CHECK7-COMPLETE THE INSTALLATION.
IfChecks 1through6havebeen satisfactory, andtheliner isan
acceptable size as determined by the tables in National Fuel
Gas Code NFPA 54/ANSI Z223.1 - latest edition and in the
NationalStandardofCanada,CAN/CSAB149.1andCAN/CSA
B149.2 - latest editions and amendments, then the clay tile
liner can probably be used as a vent for the gas appliances.
However, the installer must keep in mind the following factors
which may render the tile liner unsuitable for use as a vent:

16
FIX 4-RELINING
ReliningoptionsincludeBventandflexibleliners.
Ifthechimney has diagonal offsets, Bventprobablycannot be
used.
If B vent is to be used, it must be supported adequately. Sup-
ports (such as fire stops or thimbles) must be used to prevent
the B vent from coming into direct contact with the tile liner or
chimneywalls.Direct contact would result in higher heat loss,
with an increased possibility of poor venting system perfor-
mance.
Itisnot acceptable to ventoneapplianceinsidethe B vent and
other appliances outside. The excess space between the B
vent and the chimney walls must be covered at the top of the
chimneybyaweatherproof, corrosion resistant flashing.
The B vent should then be topped with a listed vent cap. The
listed vent cap will, when installed per the manufacturer’s in-
structions,prevent problems due to rain,birds,orwind effects.
AB-ventinstalledasdescribedinthissectionisconsideredto
be an enclosed vent system, and the sizing tables in National
Fuel Gas Code NFPA 54/ANSI Z223.1 - latest edition and in
theNational Standard of Canada,CAN/CSAB149.1 andCAN/
CSA B149.2 - latest editions and amendments may be used.
If a flexible liner is to be used, it must be made of the proper
materials:
• For most residential applications, an aluminum liner
shouldbeacceptable.
• If the combustion air supplied to the furnace will be
contaminatedwithcompoundscontainingchlorine or
fluorine, a liner ofAL 29-4C stainless steel should be
used. Common sources of chlorine and fluorine
compounds include indoor swimming pools and
chlorinebleaches,paintstrippers,adhesives,paints,
varnishes, sealers, waxes (which are not yet dried)
andsolventsusedduringconstructionandremodeling.
Variouscommercialandindustrialprocessesmayalso
besources of chlorine/fluorine compounds.
• Heaviergauge300and400seriesstainlesssteelliners
weredevelopedfor usewithoilorsolidfuelappliances.
Theyarenotsuitableforusewithgas-firedappliances.
Flexibleliners specifically intended and testedforgas
applications are listed in the UL “Gas and Oil
EquipmentDirectory”. (ULStandard1777).
For sizing of flexible liners, see Note 22 and the tables in the
NationalFuelGasCode NFPA54/ANSIZ223.1 - latest edition
andin theNationalStandardof Canada,CAN/CSAB149.1 and
CAN/CSAB149.2-latesteditionsand amendments.
To install the liner, read and follow the liner manufacturer’s in-
structionsandyourlocalcodes.Excesslinerlengthshouldbe
pulledout of the chimney and cutoff.Use caution when doing
this, as the cut edges of flexible liners may be sharp. Do not
spiral excess liner inside of the chimney. Support the liner as
recommendedby the liner manufacturer.
Somemanufacturers offlexibleliners offeraninsulation sleeve
designed to be added to the liner before it is installed in the
chimney.(Pouredinsulation,either vermiculite orothermateri-
als,isnolongerrecommended.)Insulationwillneedtobeadded
to the flexible liner if:
• It is required by the liner manufacturer’s instructions.
• The previous liner was properly sized and installed,
andsuffered fromcondensationdamage.
• It is required by your local building codes.
Evenif none ofthosethree conditions existwhichrequire addi-
tional liner insulation, the installer may wish to consider it if:
• The local climate is very cold.
• The chimney is very tall.
• Theventconnectors usedareverylongor havealarge
numberof elbows.
• Localexperience indicates thatflexibleliners installed
without insulation are likely to have condensation
problems.
Insulation must be selected and installed in accordance with
thelinermanufacturer’sinstructions.
Finally,capthechimneyandterminate the liner in accordance
withthelinermanufacturer’sinstructions.
E LECTRICAL C ONNECTIONS
HIGH VOLTAGE !
T O AVOID THE RISK OF ELECTRICAL SHOCK , WIRING TO
THE UNIT MUST BE POLARIZED AND GROUNDED .
WARNING
HIGH VOLTAGE !
T O AVOID PERSONAL INJURY OR DEATH DUE TO
ELECTRICAL SHOCK , DISCONNECT ELECTRICAL POWER
BEFORE SERVICING OR CHANGING ANY ELECTRICAL
WIRING .
WARNING
L ABEL ALL WIRES PRIOR TO DISCONNECTION WHEN SERVICING
CONTROLS . W IRING ERRORS CAN CAUSE IMPROPER AND DANGEROUS
OPERATION . V ERIFY PROPER OPERATION AFTER SERVICING .
CAUTION
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

17
WIRINGHARNESS
The wiring harness is an integral part of this furnace. Field
alteration to comply with electrical codes should not be re-
quired. Wiresarecolorcoded for identification purposes. Re-
fertothewiring diagram for wire routings. If any of the original
wireassuppliedwiththe furnace must be replaced, it must be
replacedwithwiringmaterialhaving a temperature rating of at
least 105° C. Any replacement wiring must be a copper con-
ductor.
115VOLTLINE CONNECTIONS
Beforeproceedingwith electrical connections, ensure that the
supplyvoltage,frequency,andphase correspondtothat speci-
fiedontheunitratingplate. Powersupplytothefurnacemust
be NEC Class 1, and must comply with all applicable codes.
Thefurnacemustbeelectricallygroundedinaccordancewith
local codes or, in their absence, with the latest edition of The
National Electric Code,ANSI NFPA 70 and/or The Canadian
ElectricCodeCSAC22.1.
Useaseparate fused branch electrical circuit containingprop-
erly sized wire, and fuse or circuit breaker. The fuse or circuit
breakermustbesizedinaccordancewiththemaximum over-
currentprotectionspecifiedon the unit rating plate. An electri-
caldisconnect must be provided atthe furnace location.
Line voltage wiring must enter into the junction box provided
withthefurnace.
NOTE: Line polarity must be observed when making field
connections.
FOSSILFUELAPPLICATIONS
Thisfurnacecanbeused in conjunction with a heat pump in a
fossilfuelapplication. Afossil fuel application refers to a com-
bined gas furnace and heat pump installation which uses an
outdoor temperature sensor to determine the most cost effi-
cientmeansofheating (heat pump, gas furnace, or both).
A heat pump thermostat with two stages of heat is required to
properlyuseafurnace in conjunction with a heat pump. Refer
to the fossil fuel kit installation instructions for additional ther-
mostatrequirements.
Strictlyfollow the wiring guidelines in the fossil fuel kit installa-
tioninstructions. Allfurnaceconnections must be made to the
furnaceintegrated control module andtheFURNACE terminal
strip on the fossil fuel control board.
JUNCTIONBOXRELOCATION
E DGES OF SHEET METAL HOLES MAY BE SHARP . U SE GLOVES AS A
PRECAUTION WHEN REMOVING HOLE PLUGS .
WARNING
Linevoltageconnections can be made through either the right
orleftside panel. The furnace is shippedconfiguredfora right
side electrical connection. To make electrical connections
throughthe opposite side of thefurnace,thejunction box must
be relocated to the left side prior to making electrical connec-
tions. Torelocatethejunction box,performthefollowing steps.
T O PREVENT PERSONAL INJURY OR DEATH DUE TO ELECTRIC SHOCK ,
DISCONNECT ELECTRICAL POWER BEFORE INSTALLING OR SERVICING THIS
UNIT .
WARNING
1. Removebothdoorsfromthe furnace.
2. Removeand savethe screwsholdingthe junctionboxto
the right side of the furnace.
3. Modelsthat have thejunction box located in the burner
compartmentwill need to move thejunctionboxdirectly
over.
4. Attach the junction box to the left side of the furnace,
using the screws removed in step 2.
5. Check the location of the wiring. Confirm that it will not
bedamagedbyheatfromtheburners or by the rotation
of the fan. Also confirm that wiring location will not
interferewith filter removalorothermaintenance.
Afterthejunction box is inthedesiredlocation,use washers to
connectfield-suppliedconduittothejunctionboxin accordance
with NEC and local codes. Connect hot, neutral, and ground
wires as shown in the furnace wiring diagram. The wires and
groundscrewarelocatedin the furnace junction box.
NOTE: In downflow applications the power leads should be
routed through the supplied wire tabs when rotating junction
box to the left side.
Low voltage wires may be connected to the terminal strip.
IMPORTANTNOTE:Toavoid possibleequipment malfunction,
route the low voltage wires to avoid interference with filter re-
movalor other maintenance.
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

18
To ensure proper unit grounding, the ground wire should run
fromthe furnace groundscrewlocatedinside thefurnacejunc-
tion box all the way back to the electrical panel. NOTE: Do
not use gas piping as an electrical ground. To confirm proper
unit grounding, turn off the electrical power and perform the
followingcheck.
1. Measure resistance between the neutral (white)
connectionandoneof the burners.
2. Resistance should measure 10 ohms or less.
This furnace is equipped with a blower door interlock switch
whichinterruptsunitvoltagewhentheblowerdoorisopenedfor
servicing. Do not defeat this switch.
24VOLT THERMOSTAT WIRING
NOTE: Wire routing must not interfere with circulator blower
operation,filter removal, orroutinemaintenance.
Lowvoltageconnectionscanbe made through either the right
orleft sidepanel.Thermostat wiringentranceholes arelocated
in the blower compartment. The following figure shows con-
nections for a “heat only” system and “heat/cool system”.
Furnace
Control Furnace
Control
Remote
Condensing
Unit
Heating
Room
Thermostat
Heating/Cooling
Room Thermostat
WW
Typical Field Wiring (24 VAC Control Circuit)
This furnace is equipped with a 40 VAtransformer to facilitate
usewithmost cooling equipment. Consult the wiring diagram,
located on the blower compartment door, for further details of
115 Volt and 24 Volt wiring.
A single-stage thermostat with only one heating stage can be
used to control this furnace.
GME8&AMEH8FURNACES WITH 2-STAGE CONDENSER
FIELDWIRING
The GME8 and AMEH8 model furnaces may be used with
a 2-stage outdoor air conditioner. Atwo stage cooling/single
stage gas heat thermostat is required, in addition to a field
supplied relay. The relay must have a 24VAC coil and
contacts rated for up to 1 horse power at 125VAC.
1. Install the field supplied relay on the control mount-
ing panel near the furnace ignition control. The relay
should be installed such that the motor leads will
reach the relay contact terminals.
2. Connect the “Y2” (high stage cool) thermostat
terminal to one coil terminal of the field supplied
relay. Connect the other field supplied relay coil
terminal to the “C” terminal on the furnace ignition
control. Typical 18AWG thermostat wire may be
used.
3. Connectthe common terminal ofthe field supplied
relayto the “LINE-H” terminal on the furnace ignition
control. Usewiring having copper conductors only
and a temperature rating of at least 105°C.
4. Using the GME8 airflow tables in this manual,
determinethemotor speed tap needed to deliver the
requiredhigh stage cooling airflow. Connectthe
selected motor speed tap to the normally open
terminal on the field supplied relay. Use wiring
havingcopperconductorsonlyandatemperature
rating of at least 105°C.
5. See the wiring schematic below.
Furnace
Control
Remote Condensing Unit
Heating/Cooling
Room Thermostat
Y
Y1
Y
1
Y
2
Lo-Heat
Hi-Heat
Cool
Line-H
T4 T2
T3 T5
ECO-TECH
MOTOR
Field
Supplied
Relay
Y
2
Field Wiring for GME8 & AMEH8 Furnaces
with 2-Stage Condenser
SETTINGTHEHEAT ANTICIPATOR
The following method should be used in measuring the amp
draw of the control circuit to assure proper adjustment of the
thermostatheatanticipator
• Wrap the “R” leg around a clip-on ammeter 10 times.
• Energizethefurnaceinthe heat mode.
• Recordthe reading.
• Dividethisreadingby 10.
• Set the heat anticipator on the thermostat to match
thisreading.
Example: If the reading on the ammeter is “4”, divide this by
10. The anticipator setting will be .4 amps.

19
115VOLTLINECONNECTION OFACCESSORIES
ELECTRONICAIRCLEANER
(GME8,AMEH8, GDH8,ADSH8& (A/G)MH8MODELSONLY)
HIGH VOLTAGE !
T O AVOID PERSONAL INJURY OR DEATH DUE TO
ELECTRICAL SHOCK , DISCONNECT ELECTRICAL POWER
BEFORE SERVICING OR CHANGING ANY ELECTRICAL
WIRING .
WARNING
The furnace integrated control module is equipped with line
voltageaccessory terminalsforcontrollingpowerto anoptional
field-suppliedelectronic air cleaner.
The accessory load specifications are as follows:
Electronic Air Cleaner 1.0 Amp maximum at 120 VAC
TurnOFFpowerto the furnace before installing any accesso-
ries. Follow the air cleaner manufacturers’ instructions for lo-
cating, mounting, grounding, and controlling these accesso-
ries. Accessory wiring connections are to be made through
the1/4" quick connect terminals provided onthe furnace inte-
gratedcontrolmodule. Theelectronicaircleanerhotterminal
is identified as EAC-H and the neutral terminal is identified as
NEUTRAL. All field wiring must conform to applicable codes.
Connectionsshould bemadeas showninthe followingillustra-
tion.
EAC-H Line Transformer Line Transformer EAC
A
ir Cleaner
Control Module
Hot 120 VAC Neutral 120 VAC
Optional
A
ccessories
GME8,AMEH8,GDH8,ADSH8&(A/G)MH8MODELSONLY
If it is necessary for the installer to supply additional line volt-
agewiring to theinsideofthe furnace, thewiringmustconform
to all local codes, and have a minimum temperature rating of
105°C. All line voltage wire splices must be made inside the
furnacejunctionbox.
Theintegratedcontrolmoduleelectronicaircleanerterminals
(EAC)areenergizedwith115voltswheneverthecirculatorblower
isenergized.
24VAC HUMIDIFIER
The yellow wire connected to the I.D. Blower pressure switch
ispowered anytime thepressureswitch is closedandprovides
24 VAC humidifier control. Remove the yellow wire and con-
necta field supplied jumperwirewitha “piggyback”terminalto
thepressureswitchterminal. Reconnect the yellow wire to the
“piggyback” terminal on the jumper wire and then connect the
24 VAC line of the humidifier to the stripped end of the jumper
wire.Using awirenut orafield-supplied quickconnectterminal
canmakethis connection. The wiring must conform toalllocal
andnationalcodes. Connect the COM sideofthehumidifier to
the B/C terminal on the furnace control board (or to the COM
side of the 24 VAC transformer). DO NOT CONNECT 115V
HUMIDIFIERTO THESE TERMINALS.
G AS S UPPLY AND P IPING
Thefurnacerating plate includes the approvedfurnacegasin-
put rating and gas types. The furnace must be equipped to
operateon the type of gas applied. Thisincludesany conver-
sionkitsrequiredforalternatefuelsand/orhighaltitude.
CAUTION
T O PREVENT UNRELIABLE OPERATION OR EQUIPMENT DAMAGE , THE
INLET GAS SUPPLY PRESSURE MUST BE AS SPECIFIED ON THE UNIT
RATING PLATE WITH ALL OTHER HOUSEHOLD GAS FIRED APPLIANCES
OPERATING .
Inletgassupplypressuresmustbemaintainedwithintheranges
specified in the following table. The supply pressure must be
constantand available with all otherhouseholdgasfired appli-
ances operating. The minimum gas supply pressure must be
maintainedtopreventunreliable ignition. The maximum must
notbe exceeded topreventunitoverfiring.
NOTE: Do not remove the gas valve inlet plug before the gas
lineis installed. replace ifwateror debris hasbeenintroduced.
Natural Gas Minimum: 4.5" w.c. Maximum: 10.0" w.c.
Propane Gas Minimum: 11.0" w.c. Maximum: 13.0" w.c.
INLET GAS SUPPLY PRESSURE
NOTE: Adjustingtheminimumsupplypressurebelowthe limits
inthe abovetablecould leadtounreliable ignition. Gasinputto
the burners must not exceed the rated input shown on the
rating plate. Overfiring of the furnace can result in premature
heat exchanger failure. Gas pressures in excess of 13 inches
water column can also cause permanent damage to the gas
valve.
Atall altitudes,themanifold pressure mustbewithin 0.3inches
w.c. of that listed in the Specification Sheet applicable to your
modelforthefuelused.At all altitudes and with either fuel, the
airtemperature rise must be within the range listedonthefur-
nace nameplate. Should this appliance be converted to LP,
refer to the instructions included in the factory authorized LP
conversionkit.

20
HIGHALTITUDEDERATE
IMPORTANT NOTE: The furnace, as shipped, requires no
changetorunbetween0-5500feet.Donot attemptto increase
the firing rate by changing orifices or increasing the manifold
pressure below 5500 feet. This can cause poor combustion
andequipment failure.
High altitude installations above 5500 feet may require both a
pressure switch and an orifice change. These changes are
necessarytocompensateforthenaturalreductionintheden-
sity of both the gas fuel and the combustion air at higher alti-
tude.
Forinstallations above 5500feet,pleaserefer to your distribu-
torforrequiredkit(s).
Contact the distributor for a tabular listing of appropriate
manufacturer’skitsfor propane gas and/or high altitudeinstal-
lations. The indicated kits must be used to insure safe and
properfurnaceoperation. Allconversionsmust be performed
byaqualifiedinstaller, or service agency.
PROPANEGAS CONVERSION
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 .
This unit is configured for natural gas. The appropriate
manufacturer’spropane gasconversion kit,mustbe appliedfor
propane gas installations. Refer to the “Propane Gas and/or
HighAltitude Installations” section for details.
If converting to LP gas, it is recommended that an LPLP0* kit
also be installed. The use of this kit will prevent the furnace
from firing when the LP gas supply pressure is too low to sup-
portproper combustion.
Models using Single Stage Gas Valves
Altitude Gas Kit Orifice Manifold
Pressure Pressure Switch
Propane LPT-03 #55 10.0" w.c.
NOTE:
*
M
S
81405DN
**
models utilize
#
43 ori
f
ices in Natural gas
applications.
0 - 5500
Natural None #45 3.5" w.c.
None
Modelsusing 2-Stage GasValves
High
Stage Low Stage
Natural None #45 3.5" w.c. 1.9" w .c. None
Propane LPM-06 #55 10.0" w.c. 6.0" w .c. None
0 - 5500
NOTE: *MH81405DN** models utilize #43 orifices in Natural gas
applications.
Gas Altitude Kit Orifice
Manifold Pressure Pressure
Sw itch
Change
Contact your distributor for a tabular listing of appropriate
manufacturer’skitsfor propane gas and/or high altitudeinstal-
lations. The indicated kits must be used to insure safe and
properfurnaceoperation. Allconversionsmust be performed
byaqualifiedinstaller, or service agency.
GASPIPINGCONNECTIONS
T O AVOID POSSIBLE UNSATISFACTORY OPERATION
PMENT , USE THE PROPER SIZE
OF NATURAL / PROPANE GAS PIPING NEEDED WHEN RUNNING PIPE FROM
THE METER / TANK TO THE FURNACE .
OR EQUIPMENT
DAMAGE DUE TO UNDERFIRING OF EQUI
WARNING
When sizing a trunk line, be sure to include all appliances
whichwilloperatesimultaneously.
The gas piping supplying the furnace must be properly sized
basedon the gas flow required,specificgravityof the gas, and
length of the run. The gas line installation must comply with
local codes, or in their absence, with the latest edition of the
NationalFuelGasCode, NFPA54/ANSI Z223.1.
Natural Gas Capacity of Pipe
In Cubic Feet of Gas Per Hour (CFH)
Length of Nominal Black Pipe Size
Pipe in Feet 1/2" 3/4" 1" 1 1/4" 1 1/2"
10 132 278 520 1050 1600
20 92 190 350 730 1100
30 73 152 285 590 980
40 63 130 245 500 760
50 56 115 215 440 670
60 50 105 195 400 610
70 46 96 180 370 560
80 43 90 170 350 530
90 40 84 160 320 490
100 38 79 150 305 460
(Pressure 0.5 psig or less and pressure drop of 0.3" W.C.; Based on
0.60 Specific Gravity Gas)
CFH = BTUHFurnace Input
Heating Value of Gas (BTU/Cubic Foot)
Toconnectthefurnace to thebuilding’sgaspiping,the installer
mustsupplyagroundjointunion,dripleg, manualshutoff valve,
and line and fittings to connect to gas valve. In some cases,
theinstallermayalsoneedtosupplyatransitionpiecefrom1/
2" pipe to a larger pipe size.
Thefollowingstipulations apply when connecting gas piping.
• Useblack iron orsteelpipe and fittingsforthe building
piping.