Nordyne M3RL Series User manual

Installation Instructions
M3RLSeries 90+DownflowCondensingFurnace
Direct Vent (Sealed Combustion) Forced Air Gas Furnaces
LEAVE THESE INSTRUCTIONS WITH THE HOMEOWNER.
!WARNING:
FIRE OR EXPLOSION HAZARD
Failure to follow safety warnings exactly could
result in serious injury, death or property
damage.
!ADVERTISSEMENT:
RISQUE D’INCENDIE OU D’EXPLOSION
Lenon-respectdesavertissementsdesécurité
pourrait entraîner des blessures graves, la
mort ou des dommages matériels.
– Donotstoreorusegasolineorotherflammable
vapors and liquids in the vicinity of this or any other
appliance.
–WHAT TO DO IF YOU SMELL GAS
• Do not try to light any appliance.
• Do not touch any electrical switch; do not use any
phoneinyourbuilding.
• Leavethebuildingimmediately.
• Immediatelycallyourgassupplierfromaneighbor's
phone.Followthegassupplier'sinstructions.
• If you cannot reach your gas supplier, call the fire
department.
– Installation and service must be performed by a
qualified installer, service agency, or the gas sup-
plier.
– Ne pas entreposer ni utiliser de l’essence ni
d’autres vapeurs ou liquides inflammables dans le
voisinage de cet appareil, ni de tout autre appareil.
–QUE FAIRE S’IL Y A UNE ODEUR DE GAZ
• Ne pas tenter d’allumer aucun appareil.
•Ne toucher à aucun interrupteur électrique;
n’utiliser aucun téléphone dans le bâtiment.
• Évacuerl’immeubleimmédiatement.
• Appeler immédiatement le fournisseur de gaz en
employant le téléphone d’un voisin. Respecter à
la lettre les instructions du fournisseur de gaz.
• Si personne ne répond, appeler le service des
incendies.
– L’installation et l’entretien doivent être effectués
par un installateur qualifié, un organisme de
service ou le fournisseur de gaz.
Forinstallationin:
1. Manufactured Homes
2. ParkModelsandManufacturedBuildings
3. ModularHomes/Buildings
!WARNING:
Should overheating occur, or the
gas supply fail to shut off, shut
off the manual gas valve to the
appliance before shutting off the
electrical supply.
Improper installation, adjust-
ment, alteration, service or
maintenance can cause injury
or property damage. Refer to
this manual. For assistance or
additional information consult
a qualified installer, service
agency or the gas supplier.
BW Models
BWT Models

2

3
Application
M-Manufactured Home
Furnace Series
Comfort Model
RL - Condensing Downflow
M 3 R L - 060 A - A W
Door Color
W - White
G - Gray
Cabinet Dimensions
A - 56" x 19-3/4" x 23-3/4”
B - w/Coil Cavity,
76" x 19-3/4" x 23-3/4"
Electrical Code
A - 1PH, 60 Hz, 120 VAC
Conversion .............................................. 21
LightingandAdjustment
oftheAppliance .............................. 23
ElectricalWiring ...................................... 24
LineVoltageWiring ........................... 24
LowVoltageWiring ........................... 26
Ventilation ................................................ 26
Start-upandAdjustment ........................ 26
Start-UpProcedure ........................... 26
ShutDownProcedure ....................... 27
VerifyingandAdjustingFiringRate ... 27
TemperatureRise ............................. 27
VerifyingandAdjusting
Verifying Burner Operation.............. 28
Verifying Operation of the
Supply Air Limit Switch ................. 28
Description of Components ................ 29
Furnace Accessories............................. 29
Maintenance ........................................... 29
Combustion Air and Vent System.... 29
Air Filter(s) ....................................... 29
Lubrication........................................ 30
Condensate Drain Assembly ........... 30
Blower Compartment ....................... 30
Heat Exchanger and Burner
Maintenance .................................. 30
System Operation Information............. 30
Sequence of Operation.................... 30
Furnace Fails to Operate ................. 31
Location of Major Components .......... 32
Wiring Diagram ....................................... 33
Installation/Performance
Checklist ......................................... 35
General ...................................................... 4
UnitDimensions .................................. 4
Shipping Weights................................ 4
Furnace Specification ........................ 4
Air Flow Data ..................................... 4
Owner's Information ................................ 5
Installation Requirements...................... 6
Location.............................................. 7
Clearance ........................................... 7
Circulating Air Supply ............................ 7
Return Air Provisions.............................. 8
Air Distribution Systems ........................ 9
Duct Connector Selection.................... 10
Duct Installation .................................... 10
Venting and Combustion
Air Requirements ........................... 13
Venting Requirements .......................... 14
Vent Table ........................................ 15
Vent Pipe Material ............................ 16
Vent Pipe Length and Diameter....... 16
Vent Pipe Installation ........................ 16
Pipe Routing & Support .................... 16
Location of Outdoor Termination ..... 16
Horizontal Venting ............................ 18
Vertical Venting................................ 18
Vent Freezing Protection ................. 19
Concentric Vent Termination ........... 19
Drainage of Condensate
From Furnace................................ 19
Gas Supply and Piping ......................... 20
Leak Check....................................... 21
High Altitude Derate ......................... 21
Pressure Switch .............................. 21
TABLE OF CONTENTS
Table 1. Model Identification
Return Air Configuration
Blank - Front
T - Top
Heating Capacity
Input, BTUH (000’)

4
19-7/8
19-7/8
24-5/8
24-5/8
56-1/16
56-1/16
20-9/32
20-9/32
21-17/32
21-17/32
21-29/32
21-29/32
21-15/16
21-15/16
19-3/16
19-3/16
23-7/16
23-7/16
28-15/32
28-15/32
3-17/32
3-17/32
4-11/16
4-11/16
4-11/16
4-11/16
3-17/32
3-17/32
EXHAUST
EXHAUST
VENT
VENT
17-13/16
17-13/16
COMBUSTION
COMBUSTION
AIR
AIR
INTAKE
INTAKE
21-11/32
21-11/32
7/8 Diameter
7/8 Diameter
1-19/32
1-19/32
1-19/32
1-19/32
EXHAUST
EXHAUST
VENT
VENT
1-11/16
1-11/16
COMBUSTION
COMBUSTION
AIR
AIR
INTAKE
INTAKE
3-17/32
3-17/32
24-3/4
24-3/4
20-1/16
20-1/16
18-1/2
18-1/2
18-1/2
18-1/2
(W/ Coil Box)
(W/ Coil Box)
75-1/4
75-1/4
SIDE RETURN
SIDE RETURN
KNOCKOUTS
KNOCKOUTS
SIDE RETURN
SIDE RETURN
KNOCKOUTS
KNOCKOUTS
1-1/2
1-1/2
21-15/16
21-15/16
1-19/32
1-19/32
Cooling
Cooling
Coil
Coil
Box
Box
(W/O Coil Box)
(W/O Coil Box)
Table 2. Shipping Weight
Table 3. Furnace Specifications/Airflow Data
GENERAL
Note: Data is for Operation with Filter.
* Factory Wired Cooling Tap
** Factory Wired Heating Tap
Furnace Specifications / Airflow Data
Furnace Furnace Temp. Recommended
Input Output Rise @ A/C
Btuh Btuh .3"WC °F CFM CFM CFM CFM CFM Ton
High* 1660 1599 1544 1474 1410 4
Med-High 1512 1467 1416 1363 1304 3
Med-Low 1340 1304 1261 1217 1158 2.-1/2
60,000 54,000 35 - 65 Low** 1176 1142 1108 1025 966 2
High* 1660 1599 1544 1474 1410 4
Med-High 1512 1467 1416 1363 1304 3
Med-Low** 1340 1304 1261 1217 1158 2.-1/2
80,000 72,000 35 - 65 Low 1176 1142 1108 1025 966 2
0.4 0.5Furnace
Model No. Motor HP Motor Speed
External Static Pressure ( Inches Water Column)
0.1 0.2 0.3
M3 RL-060
M3 RL-080
1/2
1/2
TopReturnKnockouts Figure 1. Furnace Dimensions
Top Return Opening
(BWT Models)
*May includesuffix -T
Furnace Model
Shipping
Weight
(
lbs
)
M3RL 060A AW 150
M3RL 060A BW* 170
M3RL 080A AW 155
M3RL 080A BW* 175
Top View
(AW and BW Models)
1.000
1.000
21.000
12.000

5
!WARNING:
Do not use this appliance if any part
hasbeensubmergedunderwater.Im-
mediatelycallaqualifiedservicetech-
nician to inspect the appliance and to
replaceanypartofthecontrolsystem
and any gas control that has been
submerged underwater.
NOTICE TO INSTALLER
Installerisadvisedto follow carefullyallinstruc-
tions and warnings in this manual to insure
maximum performance, safety, and operating
efficiencyoftheseappliances.Improperinstalla-
tion may create hazardous conditions, and will
void the appliance warranty.
GENERAL
General Description
The M3 series gas furnaces are listed direct
vent (sealed combustion) forced air furnaces
for use with both natural and propane gases.
The M3 series is a Category IV and type FSP
furnace. The M3 furnace series has been
certified to the ANSI Z21.47/CSA2.3-2001 for
use in the United States and Canada and to the
UL307B —1995 for use in the United States.
These furnaces may be installed in:
1. Manufactured Homes.
2. Park Models and Manufactured buildings
3. ModularHomes/Buildings
The following are safety guidelines with refer-
ences to their specific sections or pages in the
manual.
1. Use only type of gas approved for this
furnace. Refer to the furnace rating plate.
2. Install this furnace only in location and
position as specified in pages 7 - 13 of
these instructions.
3. Provide adequate combustion and ventila-
tion air to the furnace space as specified in
pages 13 - 20 of these instructions.
4. Combustion products must be discharged
outdoors, connect this furnace to an ap-
proved vent system only, as specified in
pages 14-19 of these instructions.
5. Never test for gas leaks with an open
flame. Use a commercially available soap
solution made specifically for the detection
of leak to check all connections.
6. Always install furnace to operate within the
furnace’s intended temperature rise range
with a duct system that has an external
static pressure within the allowable range,
as specified in page 4 of these instruc-
tions. See furnace rating plate.
7. When a furnace is installed so that supply
ducts carry air circulated by the furnace to
areas outside the space containing the
furnace,thereturnairshallalsobehandled
by duct(s) sealed to the furnace casing
and terminating outside the space contain-
ing the furnace. Note: This section only
applies to furnaces installed with side or
top return air.
8. A gas-fired furnace for installation in a
residential garage must be installed as
specified in page 7 of these instructions.
9. The furnace is not to be used for tempo-
rary heat of buildings or structures under
construction.
M3 series furnaces are air conditioning ready
as shipped. The furnace cooling capacities of
the blower motor speed taps are shown in
Table 3. Table 2 lists the shipping weights for
the M3 series furnaces.
OWNER INFORMATION
NORDYNE has been involved in the design of
products for the manufactured home industry
since the first manufactured home or trailer
was built.
NORDYNE originated the sealed combustion
system, which separates the furnace com-
bustion system from the living area of the
home, now a standard for the manufactured
home industry.
NORDYNE engineers developed the first cen-
tral heating system and the first central air
conditioner for manufactured homes.
NORDYNE is dedicated to bringing to its cus-
tomers the finest heating and cooling comfort
possible. NORDYNE constantly seeks to fur-
ther refine its products to continuously provide
exceptional comfort.

6
Follow the instructions in this booklet carefully
and this appliance will provide many years of
superior performance.
If you wish to cool your home automatically
with a central air conditioning system investi-
gate the excellent NORDYNE cooling systems
available from your heating and cooling con-
tractor. These systems are designed to work
best with your NORDYNE furnace and have
been carefully engineered to deliver optimum
performance when mated with NORDYNE
manufactured home furnaces.
NORDYNE also offers water heaters, fireplaces
and ventilating systems specifically designed
for manufactured housing applications. Check
with your manufactured home retailer, your
heating and cooling contractor or your
distributor for information. Write directly to the
factory (PO Box 8809, O’Fallon, MO 63366) if
youarenotabletolocateasourceforNORDYNE
manufactured housing products in your area.
MANUFACTURER WARRANTY, OWNER’S
RESPONSIBILITIES
It is the sole responsibility of the homeowner to
makecertainthegasfurnacehasbeencorrectly
setupandconvertedtotheproperfuel(L.P.gas
or Natural gas) and adjusted to operate prop-
erly. All gas furnaces are manufactured for
Natural gas and must be field converted when
using L.P. gas.
Awarrantycertificatewithfulldetailsisincluded
with these instructions. However, NORDYNE
will not be responsible for any costs found nec-
essary to correct problems due to improper
setup,improperinstallation,furnaceadjustments,
improperoperatingprocedureonthepart of the
user, etc.
Some specific examples of service calls which
cannot be included in warranty payments are:
1. Converting the furnace to use another type
of gas.
2. Repairingductworkinthehomefoundtobe
faulty.
3. Correcting wiring problems in the electrical
circuit supplying the furnace.
4. Resetting circuit breakers, blown fuses or
other switches.
5. Correcting problems due to improper gas
supply pressure to the furnace.
6. Providing instructional training on how to
light and operate the furnace.
7. Furnace problems caused by installation of
an air conditioner, heat pump or other air
comfort devices.
8. Revising installation of the furnace flue
assembly.
9. Adjusting or calibrating of thermostat.
10. Any construction debris which falls into
the flue system.
Carefullyreviewtheseresponsibilitieswithyour
manufacturedhousingdealer,servicecompany
or gas supplier so there will be no misunder-
standing at a later time.
!CAUTION:
• Never attempttoalterormodifythis
furnace or any of its components.
• Never attempt to repair damaged or
inoperablecomponents.Suchaction
could cause unsafe operation, ex-
plosion,fireand/orasphyxiation.
• If a malfunction has occurred, or if
you feel that the furnace is not oper-
atingasitshould,contactaqualified
service agency or gas utility for as-
sistance.
INSTALLATION STANDARDS
Installershallbefamiliarwithandcomplywithall
codesandregulationsapplicabletotheinstalla-
tion of these heating appliances and related
equipment.Inlieuoflocalcodes,theinstallation
shall be in accordance with the current provi-
sions of one or more of the following standards.
a. Federal Manufactured Home Constructions
& Safety Standard (H.U.D. Title 24, Part
3280.707[a][2])
b. TheStandardforManufacturedHomeInstal-
lations (Manufactured Home Sites, Commu-
nities, and Set-Ups) ANSI A225.1 and/or
CAN/CSA-2240 MH Series).
c. American National Standard (ANSI-119.2/
NFPA-501C) for all recreational vehicle in-
stallations.
d. American National Standard (ANSI-Z223.1/
NFPA-54)and/orCAN/CGAB149forallgas-
fired furnace models.
e. AmericanNationalStandard(ANSI-C1/NFPA-
70)and/orCSA22.1CanadianElectricCode
Part 1 for all electrical field wiring.

7
CE générateur d'air chaud doit être installé
conformément aux instructions du fabricant et
aux codes locaux. En l'absence de code local,
respecter la norme ANSI Z223.,1, institulé Na-
tionalFuelGas Codeoules codesd'installation
CAN/GCA-B149.
The National Fuel Gas Code is available by
writing:
American National Standards Institute, Inc.
1430 Broadway
New York, NY 10018
NFPA publications are available by writing:
National Fire Protection Association
Batterymarch Park
Quincy, ME 02269
LOCATION
The furnace must be installed on a level sur-
face, and as close to the center of the air
distribution system as possible. See Figure 1
for overall dimensions to determine the re-
quired clearances in hallways, doorways,
stairs, etc. to allow the furnace to be moved to
the installation point. The furnace must be in-
stalled so that all electrical components are
protected from water.
Minimum clearances to combustible materials
arelistedinTable4. Accessforpositioningand
servicing must be considered when locating
the unit.
This furnace is certified for use on wood
flooring. The furnace must be installed on a
solid surface and must be level front-to-back
and side-to-side. This furnace must not be
installed directly on carpeting, tile, or any com-
Table 4. Minimum Clearances
*Note:For1”clearance,useafullylouvereddoorwithat
least400squareinchesoffreeairflowarea.
CLOSET
A
LCOVE
A
LL MODELS Inches Inches
Front 1* 1*
Back 0 0
Sides 0 0
V
ent 0 0
Top 6 6
Duct (Plenum)
w/ Coil Box 0 0
w/o Coil Box 1/4 1/4
(within 3 feet)
bustible material other than wood flooring. The
furnace may be installed on combustible floor-
ing when installed on a Nordyne duct connec-
tor (see Table 5).
The ductwork within 3 feet of the furnaces
without the A/C coil box must be installed such
that surfaces are at least 1/4" from combustible
materials.
When installed in a residential garage, the fur-
nacemustbe positioned sotheburners and the
source of the ignition are located no less than
18 inches above the floor and protected from
physical damage by vehicles.
CIRCULATING AIR SUPPLY
!WARNING:
Products of combustion must not be
allowedtoenterthereturnairopenings
of the furnace or the circulating air
supply. Failure to prevent products of
combustion from being circulated into
the living space can create potentially
hazardousconditionsincludingcarbon
monoxidepoisoningthatcouldresultin
personal injury or death.
The floor or platform on which the
furnaceismountedmustprovidesound
physical support of the furnace with no
gaps, cracks, or sagging between the
furnace and the floor or platform.
The circulating air ductwork must not
be connected to any other heat
producing device such as a fireplace
insert, stove, etc.
GENERAL
Plenums and air ducts must be installed in
accordance with the Standard for the Installa-
tionofAirConditioningandVentilatingSystems
(NFPA No. 90A) or the Standard for the Instal-
lationofWarmAirHeatingandAirConditioning
Systems (NFPA No. 90B).

8
Figure 4.
Figure 3.
13 1/4"
10 1/4"
19”
19"
TopView
ofDuct
Connector
x
SUPPLY AIR DUCT
FLOOR CAVITY
(depth equal to "X" in Figure 5 and Table 5)
RETURNAIRPROVISIONS
U.S.A. home manufacturers shall comply with
all of the following conditions to have accept-
able return air systems for closet installed
forced air heating appliances:
a. Regardless of the location, the return air
opening into the closet shall not be less than
specified in the appliance’s listing.
b. Means shall be provided to prevent inadvert-
ent closure by a flat object placed over the
return air opening when it is located in the
floor of the closet (versus the vertical front
or side wall).
c. Closet installations must use a louvered
door having a minimum free area of 235 sq.
in. when located 6” from furnace. For clear-
ance between 1” and 6” from furnace, re-
quirements are a louvered door with mini-
mum of 235 sq. in. free area, with the open-
ings in closet door directly inline with the
louvered openings in the furnace door. For
1” clearance from furnace, use a fully lou-
vered door with at least 400 sq. in. of free
airflow area.
d. The cross-sectional area of the return duct
system leading into the closet, when located
Figure 2. Non-Platinum
Supply Duct System
A Single trunk duct
BDual trunk duct
w/crossover connector
CTransition duct
w/branches
Table 5. Duct Connectors
Use Duct Connector
If "X" (Floor Cavity) is: Model Part Number:
English Metric
(
mm
)
Finger Tab Screw Down
7/8" 22 901987 904008
2" 51 901988 904009
4 1/4" 108 901989 904010
6 1/4" 150 901990 904011
8 1/4" 210 901991 904012
10 1/4" 260 901992 904013
12 1/4" 311 901993 904014
inthefloororceilingshallnotbelessthan235
square inches.
e. The total free area of openings in the floor or
ceiling registers serving the return air duct
system must be at least 352 sq. in. At least
one register should be located where it is not
likely to be covered by carpeting, boxes and
other objects.
f. Materials located in the return duct system
must have a flame spread classification of
200 or less. This includes a closet door if the
furnace is in a closet.
g. Noncombustible pans having 1" upturned
flanges are located beneath openings in a
floor duct system.
h. Wiring materials located in the return duct
system shall conform to Articles 300-22 of
the National Electrical Code (ANSI C1/
NFPA-70).

9
Figure 6. Closet or Alcove
10"
23 -1/4"
FLOOR
OPENING
C
L
C
L
ALT. FUEL
LINE HOLES
SIDE WALL
REAR WALL
FUEL LINE
HOLE
Figure 5.
XSEE
TABLE 5
REDUCER
FELT-SEAL(1)
SPACERS
C
( )OPENING TO DUCT
(1) WITH PLATE (C) REMOVED
OPENING BECOMES
13-1/4” x 13-1/4”
(2) WITH PLATE (C) REMOVED
OPENING BECOMES
13" X 13". WITH REDUCER
IT IS 13" X 10-1/8".
(1) FINGER TAB DUCT CONNECTOR ONLY
(2) SCREW DOWN DUCT CONNECTOR ONLY
i. Gas piping is not run in or through the return
duct system.
j. Test the negative pressure in the closet with
theair-circulatingfanoperatingathighspeed
and the closet closed. The negative
pressure is to be no more negative than
minus 0.05 inch water column.
k. For floor return systems, the manufactured
home manufacturer shall affix a prominent
marking on or near the appliance where it
can be easily read when the closet door is
open. The marking shall read:
!
CAUTION:
HAZARD OF ASPHYXIATION: Do not
cover or restrict return air opening.
l. Air conditioning systems may require more
duct register and open louver area to ob-
tain necessary airflow. Use NORDYNE’s
certiduct program to determine proper duct
size for A/C.
DUCTED RETURN AIR
M3furnaces with model numbers ending in AW
or BW are factory configured for the return air
to flow through the front louvered door. The
return air may also be attached to either side or
the top of the furnace cabinet using a field
installedkit. RefertoTable12fortheNORDYNE
ducted return kit P/N number. The location and
size of the side and top return air connections
areshowninFigure1.Thefiltersizefortheside
return air is 20” x 20” x 1”. For top return the
filter size is 24” x 16” x 1”.
M3 furnaces with model numbers ending in
BWT are factory configured for the return air to
enter the top of the furnace.

10
Figure 7. Cut-Out Locations
2-3/4
2
1-3/4
17-29/32
21-7/16
1-3/4
3-19/32
14-1/2
14-1/2
2-1/4
23-1/4
12-7/814-3/4
20
24 21-3/4
10
15-1/2
˚
ALT FUEL LINE
ENTRY
1-1/4
VENT
FUEL LINE ENTRY
FURNACE
OUTER DOOR
FLOOR CUT-OUT
FOR DUCT CONNECTIONS
FLOOR CUT-OUT
FOR OPTIONAL
COOLING COIL
FOR NON-PLATINUM
SERIES UNITS
FURNACE OUTLINE
REAR WALL OF CLOSET OR ALCOVE
COMBUSTION AIR INTAKE
AIRDISTRIBUTIONSYSTEMS
For proper air distribution, the supply duct
system must be designed so that the static
pressure measured external to the furnace
does not exceed the listed static pressure
rating shown on the furnace rating plate.
Three typical distribution systems are illus-
trated in Figure 2. Location, size, and number
of registers should be selected on the basis of
best air distribution and floor plan of the home.
DUCTCONNECTORSELECTION
PLATINUM SERIES
a. For Platinum ready construction use
the 14” round plenum, p/n: 903896.
NON-PLATINUM SERIES
a. Determine depth of floor cavity from
surface of floor to top of supply air duct
(See Figure 3).
b. Select appropriate model from Table 5
whichmatchesX-dimensionofthefloor
cavity. To maximize air delivery, re-
move reducer “C” (see Figure 5) to
obtain the largest open area that will fit
the duct/floor construction.
DUCTINSTALLATION
Required floor, ceiling, and roof cut-out open-
ings must be carefully located to avoid mis-
alignment of the furnace (see Figures 6 & 7).
Installation procedures are suggested for typi-
cal furnace installations and need not be fol-
lowed in the exact listed sequence.
CUT OUT FLOOR OPENING & FUEL LINE
HOLE
a. Determine center of closet or alcove (Fig-
ures 7 & 8).
b. Locate center of the floor opening, mea-
sured 10" from the rear wall, and mark cut-
out measuring approximately 14-1/2" by 14-
1/2" (± 1”) for model duct connector used
(refer to Figures 4 & 5).
c. Locate center of gas line hole, measured 23-
1/4"fromtherearwalland 6-5/8" to the leftof
center of the floor cut-out (See Figure 6) or

11
Figure 9. Duct Connector
Screw Down
Duct Connectors Platinum Series
Figure 8. Mounting Plate
REAR WALL
SUPPLY AIR DUCT
FUEL
LINE
HOLES
MOUNTING
PLATE
FLOOR
OPENING
BEND CONNECTOR TABS
UNDER DUCT OPENING
5-1/4" to the left of center of the floor cut-out,
or for entry through right-side of furnace
measured 9" to the right of center of the floor
cut-out.
d. Cut out floor opening and one gas line hole.
CUT DUCT OPENING (FINGER TABBED
ONLY)
a. Place duct connector through the floor open-
ing with bottom tabs resting on top of the
supply air duct.
b. Centerductconnectorandpushbackagainst
rear edge of floor opening.
c. Mark cut-out location (tab area) and remove
duct connector.
d. Cut out duct opening 1/16" larger than area
marked.
INSTALL FURNACE MOUNTING PLATE
a. Place mounting plate (supplied within duct
connector) at rear of the floor opening (See
Figure 9).
INSTALLING PLATINUM SERIES 14”
ROUND DUCT CONNECTOR
a. Place duct connector through the floor open-
ing. (See Figure 9).
b. Secure duct connector to floor.
INSTALLING SCREW DOWN DUCT CON-
NECTOR
a. Apply a bead of caulking, mastic, or other
approved sealant around bottom side of 1/2”
flange and restrictor plate, when applicable.
b. Locate the duct connector over duct and
carefully lower screw down duct connector
into place.
c. Once duct connector is located on duct,
temporarilyholdinplacewhilefasteningduct
connector to the floor using flat head screws
or nails. Be sure flanges of duct connector
stay in contact with the duct.
d. Screw plenum to duct making sure a seal is
made between the duct and the duct con-
Finger Tabbed
Duct Connectors
14” SUPPLY
CONNECTION
FUEL
LINE
HOLES
SCREWS
MOUNTING
PLATE
PLENUM
SUPPLY AIR DUCT
FUEL
LINE
HOLES
MOUNTING
PLATE
FLOOR
OPENING
SCREWS
REAR WALL
MOUNTING
PLATE
FLOOR
OPENING FUEL
LINE
HOLES
SUPPLY AIR DUCT

12
TABS TABS
DUCT DUCT
1. INSERT DUCT PLENUM CONNECTOR
INTO DUCT CUT-OUT. 2. BEND BOTTOM TABS OVER AND ONTO THE UNDERNEATH
DUCT SERVICE.
Staple Folded Duct
Flap (typ) to side of Duct
Connector
Duct
STEP 4.
STEP 1.
"A" "A"
"B"
"B" Cut- Out
Area"A"
Cut- Out
Area "A"
Fold Back Flap "B"
Fold Back Flap "B"
Top of Duct
"A" "A"
STEP 2.
"B"
"B"
Fold Back Flap"B"
Cut
Lines Duct
Fold Back Flap"B"
STEP 3.
Bend Duct Connector Tabs Up
and Over- (along length of duct)
Duct
Flap "B"
Duct
Duct
Duct Connector
Narrow Duct
Figure 12. Alternate Installation
Figure 11. Narrow Duct Installation
Figure 10. Installation of Duct Connector
nector. Additional screws may be added if
required.
e. Cut away along edge of flange allowing the
center to drop into the duct. Remove section
of duct with caution, as edges will be sharp.
INSTALLING FINGER TABBED DUCT CON-
NECTORS
a. Place duct connector through the floor open-
ing with bottom tabs extending through the
duct opening. (See Figure 9)
b. Secure duct connector to floor.
c. Bendbottomtabsunderanduptightlyagainst
the supply air duct (See Figure 10).
NOTE: The duct connector is designed for use
on ducts 12" in width. When using the connec-
tor on 12" wide ducts, there may be insufficient
clearance to bend the tabs on two sides of the
duct connector. In such cases the tabs may be
attached to the sides of the duct by using sheet
metal screws or other suitable fasteners. (See
Figure 11).
If sealant, mastic, or tape is used to provide a
better seal, it should be approved by applicable
national or local codes.
ALTERNATE ATTACHMENT METHODS
This procedure may also be used to install a
furnace duct connector to narrow metal
ductwork where insufficient clearance prevents
bending of the duct connector tabs at the
side(s) of the duct. (See Figure 12).
1. Score and cut the top of the metal duct as
indicated in Step 1 or Step 2. With Step 1
choice,alsocutoutthemetalfromtheshaded
area “A”.
2. Fold the duct flap “B” up, (See Step 3).

13
MTG. PLATE TABS SLIDE FURNACE
ALL THE WAY BACK
ONTO MTG. PLATE
SUPPLY AIR DUCT
Knockout Over Holes
SECURE FURNACE
WITH 2 FASTENERS AT FRONT
CORNER HOLES
SUPPLY AIR DUCT
FUEL
LINE
HOLES
MTG. PLATE TABS SLIDE FURNACE
ALL THE WAY BACK
ONTO MTG. PLATE
SECURE FURNACE
WITH 2 FASTENERS
AT FRONT CORNER HOLES
Figure 13.“A”,“B”, & Platinum
Cabinet Furnaces
Figure 14. “A” Cabinet Furnace on 911969
Coil Cabinet (Non-Platinum Series)
3. At the front-to-back of duct run (Area “A”),
bend the duct tabs and secure them directly
to the duct.
4. At Area “B”, bend the duct tabs up and back
over, around the duct connector, (See
Step 3).
5. Fold/form theductflapagainst thesideof the
duct connector and attach as shown, (See
Step 4). Use three (3) staples (minimum) on
each duct flap OR, if a 2X block/joist is not
provided, use two (2) sheet metal screws
(minimum) on each duct flap. An alternate
attachment method is acceptable, as long
as the plenum is securely attached.
6. Tape the duct flap edges with an approved
tape for a leak-free joint.
INSTALL FURNACE
a. Remove furnace outer door(s) and bottom
fuel line knockout.
b. Place furnace onto duct connector and cen-
ter with floor opening.
c. Slide ontomountingplate.(Bottomrearslots
on furnace should engage with mounting
plate tabs.)
d. Secure front with one (1) fastener at each
corner (See Figure 13 or 14).
NOTE: Additional fasteners may be used at
rear, sides or through door frame, as desired,
to secure furnace to closet or alcove framing.
VENTINGANDCOMBUSTIONAIR
REQUIREMENTS
!
CAUTION:
Snowmustnotbeallowedtorestrictor
blockthecombustionairintakeorvent
pipes.
General
NORDYNE condensing furnaces must be
installed with outdoor combustion air piped
directly to the furnace. Codes refer to this
type of installation as direct vent, or two pipe
installation.
Provisions must be made for adequate supply
of air for combustion and ventilation. For
United States installations, the adequacy of
airprovisionscan bedeterminedbyconsulting
the current version of the National Fuel Gas
Code (ANSI Z223.1/NPFA-54). For Canadian
installations, requirements are specified in the
National Standard of Canada (CAN/CGA
B149.1 & .2). Consult local codes for special
requirements.
NOTE: If the furnace is operated without
adequate air for combustion and ventilation, it
may not perform properly. Furnace
components may be strained by high
temperature and could fail prematurely.
!WARNING:
The combustion air piping must not be
blocked or restricted in any manner.
!WARNING:
Furnace installation using methods
other than those described in the
followingsectionsmustcomplywiththe
National Fuel Gas Code and all
applicable local codes to provide
sufficientcombustionairforthefurnace.

14
!CAUTION:
Do not allow debris to fall into the fur-
nace. This could cause unsafe opera-
tion and voids the furnace warranty.
VENTINGREQUIREMENTS
!WARNING:
FURNACE MUST NOT BE COMMON
VENTED WITH OTHER APPLIANCES.
General
Thissectionspecifiesinstallationrequirements
for 2-pipe combustion air piping. The capacity
table provided in this section applies to the
maximum equivalent lengths of vent and
combustion air intake pipe.
These condensing furnaces are classified as
"Category IV" appliances, which require
special venting materials and installation
procedures. Category IV appliances operate
with positive vent pressure and therefore
require vent systems which are thoroughly
sealed. They also produce combustion
condensate, which is slightly acidic and can
cause severe corrosion of ordinary venting
materials.Furnaceoperationcanbeadversely
affected by restrictive vent and combustion
air piping. Therefore,
vent and combustion air
piping lengths must conform completely to the
requirements of Table 6.
The furnace must be vented to the outdoors.
!
WARNING:
CARBON MONOXIDE POISONING
HAZARD
1. Seal any unused openings in the
venting system
2. Inspect the venting system for
proper size and horizontal pitch,
as required in the National Fuel
Gas Code, ANSI Z223.1 or the
CAN/CGAB149InstallationCodes
andtheseinstructions. Determine
that there is no blockage or re-
striction, leakage, corrosion and
other deficiencies which could
cause an unsafe condition.
3. So far as is practical, close all
building doors and windows and
all doors between the space in
whichtheappliance(s)connected
to the venting system are located
and other spaces of the building.
4. Follow the lighting instructions.
Place the appliance being
inspected in operation. Adjust
thermostat so appliance shall
operatecontinuously.
5. Turn on clothes dryers and any
other appliance not connected to
the venting system. Turn on any
exhaustfans,suchasrangehoods
and bathroom exhausts, so they
shall operate at maximum speed.
Donotoperateasummerexhaust
fan.
6. Close fireplace dampers.
7. Test for spillage from draft hood
equipped appliance at the draft
hoodreliefopeningafter5minutes
ofmainburneroperation. Usethe
flame of a match or candle.
8. If improper venting is observed
during any of the above tests, the
ventingsystemmustbecorrected
in accordance with the
National
FuelGasCode,ANSIZ223.1/NFPA
54
and/or CSAB149.1,NaturalGas
and Propane Installation Codes.
9. After it has been determined that
each appliance connected to the
venting system properly vents
when tested as outlined above,
return doors, windows, exhaust
fans, fireplace dampers and any
other gas burning appliance to
their previous conditions of use.
It must not be vented in common with any
otherappliance, even if that appliance is of the
condensing type. Common venting can result
inseverecorrosionof other appliances or their
venting and can allow combustion gases to

15
*NOTES
1. Subtract3.5ft.foreachadditional3"90degreeelbow.
2. Two45degreeelbowsareequivalenttoone90degreeelbow.
3. One short radius elbow is equivalent to two long radius
elbows.
4. Donotincludeterminationelbowsincalculationofventlength.
5. Thistableisapplicableforelevationsfromsealevelto4000
ft. Forhigherelevations,decreaseventpipelengthsby8%per
1000ft.ofaltitude.
6. Onlytheabovepipematerialsareapprovedforusewiththese
condensingfurnaces.
PVC,CPVC or ABS Inlet/Outlet
SCH. 40 Pipe Size 3" 3"
Model M3RL 060 50 50
Model M3RL 080 50 50
APPLICATION
MAXIMUM
DIRECT VENT, DUAL
PIPE LENGTH (ft.)*
Table 6. Vent Table
VENT TERMINAL AIR SUPPLY INLET AREA WHERE TERMINAL IS NOT PERMITTED
1In accordance with the current CSA B149.1
Natural Gas and Propane Installation Code
2In accordance with the current ANSI Z223.1 / NFPA 54
National Fuel Gas Code
† A vent shall not terminate directly above a sidewalk or paved driveway that is located between two single family
dwellings and serves both dwellings.
‡ Permitted only if veranda, porch, deck, or balcony is fully open on a minimum of two sides beneath the floor.
* For clearances not specified in ANSI Z223.1 / NFPA 54 or CSA B149.1, the following statement shall be included:
“Clearance in accordance with local installation codes, and the requirements of the gas supplier and the
manufacturer’s installation instructions.”
Canadian Installations
1
US Installations
2
A = Clearance above grade, veranda, porch,
deck, or balcony 12 inches (30 cm) 12 inches (30 cm)
B = Clearance to window or door that may be
opened 6 inches (15 cm) for appliances ≤10,000 Btuh (3 kW), 12 inches (30 cm) for
appliances > 10,000 Btuh (3 kW) and ≤
100,00 Btuh (30 kW), 36 inches (91 cm) for
appliances >100,00 Btuh (30 kW)
6 inches (15 cm) for appliances ≤10,000
Btuh (3 kW), 9 inches (23 cm) for
appliances > 10,000 Btuh (3 kW) and ≤
50,000 Btuh (15 kW), 12 inches (30 cm) for
appliances > 50,000 Btuh (15 kW)
C = Clearance to permanentl
y
closed window **
D = Vertical clearance to ventilated soffit
located above the terminal within a
horizontal distance of 2 feet (61 cm) from
the center line of the terminal
**
E = Clearance to unventilated soffit **
F = Clearance to outside corner **
G = Clearance to inside corner **
H = Clearance to each side of center line
extended above meter/re
g
ulator assembl
y
3 feet (91 cm) within a height 15 feet
above the meter/re
g
ulator assembl
y
*
I = Clearance to service regulator vent outlet 3 feet (1.83 m) *
J = Clearance to nonmechanical air supply inlet
to building or the combustion air inlet to any
other appliance
6 inches (15 cm) for appliances ≤10,000
Btuh (3 kW), 12 inches (30 cm) for
appliances > 10,000 Btuh (3 kW) and ≤
100,00 Btuh (30 kW), 36 inches (91 cm) for
appliances >100,00 Btuh (30 kW)
6 inches (15 cm) for appliances ≤10,000
Btuh (3 kW), 9 inches (23 cm) for
appliances > 10,000 Btuh (3 kW) and ≤
50,000 Btuh (15 kW), 12 inches (30 cm) for
appliances > 50,000 Btuh (15 kW)
K = Clearance to a mechanical air supply inlet 6 feet (1.83 m) 3 feet (91 cm) above if within 10 feet (3 m)
horizontally
L = Clearance above paved sidewalk or paved
driveway located on public property 7 feet (2.13 m) † *
M = Clearance under veranda, porch deck, or
balcony 12 inches (30 cm) ‡ *
Figure 15. Vent Termination Clearances for Direct Vent Furnaces

16
escape through such appliances or vents. Do
not vent the furnace to a fireplace chimney or
building chase.
If removing an existing furnace in a venting
system,theventingsystemmaynotbeproperly
sized. Totesttheventsystemwiththeremaining
appliances, follow the test outlined below.
The following steps shall be followed with each
appliance connected to the venting system
placed in operation, while any other appliances
connected to the venting system are not in
operation:
Vent Pipe Material
Vent and combustion air pipe and fittings must
be one of the following materials and must
conformtotheindicatedANSI/ASTMstandards:
Material Standard
Schedule 40 PVC D1785
PVC-DWV D2665
SDR-21 D2241
& SDR-26
ABS-DWV D2661
Schedule 40 ABS F628
Foam/Cellular Core PVC F891
Cement and primer must conform to ATSM
StandardD2564forPVCandStandardD2235
forABS. WhenjoiningPVCpipingtoABS, use
an appropriate solvent cement and procedure
perthepipingmanufacturer'srecommendation
and ASTM Standard D3138.
Vent Pipe Installation
Pipe Routing and Support
Route piping as directly as possible between
the furnace and the outdoors and remember
that routing affects pipe length limitations per
Table6. Locatethecombustionair intake and
the vent exhaust in the same atmospheric
pressure zone - i.e. both must exit the building
though the same portion of exterior wall or
roof. Vent piping must be sloped upwards not
less than 1/4" per foot in the direction from the
furnace to the terminal. This is to ensure that
any condensate flows back to the furnace
where it can be disposed of through the
condensate disposal system.
!CAUTION:
Combustionairmustnotbedrawnfrom
occupied spaces and a corrosive
atmosphere.
The quality of outdoor air must also be
considered. Be sure that the combustion air
intake is not located near a source of solvent
fumes or other chemicals which can cause
corrosion of the furnace combustion system.
Pipingmustbemechanicallysupportedsothat
its weight does not bear down on the furnace.
Supports must be at intervals no greater than
five feet, and at smaller intervals if necessary
to ensure that there are no sagging sections
to trap water (See Figures 16 & 17).
These condensing furnaces have been
certified for installation with zero clearance
betweenventpipingandcombustiblesurfaces.
However, it is good practice to allow space for
convenience in installation and service.
Location of Outdoor Terminations
Vent and combustion air intake terminations
must be located to ensure proper furnace
operation and to conform to applicable codes.
Figure15illustratesnecessarydistancesfrom
theventterminationtowindowsandbuilding
air intakes. In Canada, the Canadian Fuel
Gas Code takes precedence over these
instructions. Specifically, all minimum
distance requirements with respect to
termination of the vent piping listed below.
Thefollowinglist isasummaryof ventterminal
location requirements:
1. The termination must be 12 inches above
snow level or grade level whichever is
higher.SeeFigure18foralternatemethod
to achieve 12" above snow level.
2. The minimum distance for a direct vent
(2-pipe) installation from any door,
openablewindow, orairgravityinletis1ft.
below, 1 ft. horizontally, or 1 ft. above.
3. The vent termination shall be a minimum of
3 ft. above any forced air inlet within 10 ft.
4. The vent termination shall be located at
least 4 ft. horizontally from any electric
meter, gas meter, regulator and any relief
equipment. These distances apply ONLY
toU.S.installations.InCanada,theCana-
dian Fuel Gas Code takes precedence.

17
Figure 16. Horizontal Venting
Downflow Furnace
Seal/Caulk
Around Pipe
at Building
90˚ Elbow
12"
Min.
Normal Snow Level
Wall
Coupling
First Support Should be as Close to
Furnace Connection as Possible
Combustion Air
Intake Pipe Furnace 3" x 2"
Reducer
Exhaust
Vent
PVC or
ABS pipe
Offset with
Vent for Adequate
Dimensional Clearance
3 1/2"
SeeVentTable 4
Straps or Other Suitable
Supports at Minimum of
5 ft. Intervals
Upward Pitch - 1/4" Per Foot
Outlet ExhaustVent
Top View
6"
3 9/16" 1 7/8"
Vent
Combustion
Air Intake Pipe
Figure 17. Vertical Venting
Upward Pitch
1/4" per foot
Vent
First support should be as
close to furnace as possible
Combustion Air Intake Pipe
5'
Combustion Air
Intake Pipe Vent
Support System
onVertical Rise
Below Joints
5. Avoid areas where condensate drainage
maycauseproblemsbydroppingonplant-
ers or patios, etc. Also ensure that ex-
haust gases will not impinge on windows
or building surfaces, which may be com-
promised or damaged by condensation.
Do not install the vent terminal such that
exhaust is directed into window wells,
stairwells, under decks or into alcoves or
similar recessed areas, and do not termi-
nate above any public walkways.
6. Select the point of wall penetration where
the minimum 1/4 inch per foot of slope up
can be maintained.
!
CAUTION:
For optimal performance vent furnace
throughwallwhichexperiencestheleast
exposure to winter winds.

18
Horizontal Venting
Vent and combustion air intake terminations
must be as shown in Figure 19 unless the
concentric vent termination kit is used.
!
WARNING:
Ensurethatthecombustionairventand
the exhaust vent are configured as
shown in Fig. 19. Improper vent
termination can cause recirculation of
thefluegases.Thismayresultinfurnace
vibration. In severe cases, the furnace
willcycle,duetotheintermittentcontact
betweentheflameandtheflamesensor.
Ifyounotetheseoscillationsoccurring,
checktheventconfiguration.Makesure
thattheexhaustventdoesnothavea90
degree termination.
For horizontal venting, either the Horizontal
Exterior Vent Mounting Kit or the Concentric
Vent Termination Kit may be used (See Table
12).
For Canadian installations please refer to the
CanadianInstallationCode(CAN/CGA-B149.1
or 2) and/or local codes.
The Horizontal Exterior Vent Mounting Kit con-
sists of two face plates and an insulating gas-
ket to seal the exterior surface. A hole sized
closely to the pipe diameter must first be cut
through the wall. A short length of pipe is then
cut such that it can penetrate the wall and be
held in place by closely fitting standard cou-
plings. The face plates are retained on both
sides of the wall by the couplings, and the
gasket is retained against the wall by the outer
face plate. Face plates must be fastened to the
wall and the outside one must be flashed as
appropriate to prevent entry of water.
When the above kits are not used the following
steps are required:
1. Check the hole size cut through the exte-
rior wall. Insure that the hole diameter is
less than the diameter of the couplings to
be used.
2. Extend the vent pipe through the wall
approximately 1" and seal the area be-
tween the wall and pipe.
3. Apply couplings to the vent pipe on the
interior and exterior sides of the wall to
insurethepipecannotbepushedorpulled
through the wall.
4. Insurethecombustionairinletpipehasa90
degree termination elbow, and is pointing
downward as shown in Figures 19 & 20.
Note that a combustion air intake must be
provided with an elbow opening downward.
When the vent pipe must exit an exterior wall
close to the grade or expected snow level, a
riser should be provided as shown in Figure 18.
Insulation is required to prevent freezing of this
section of pipe.
Vertical Venting
For vertical venting, either the configuration
shown in Figure 20 or the Concentric Vent
TerminationKitmaybeused.Verticalventingis
one of the shortest routing methods when
piping vents for furnaces. The M3 furnace
operates trouble-free when the furnace is in-
stalled with a shorter vent.
•The inlet for the combustion intake pipe must
beextendedatleastonefootabovetheroofline
or snow accumulation level.
•Theoutletoftheventmustbeextendedatleast
10inches abovetheinletofthecombustionair
intake pipe.
•The vent as well as the combustion air intake
pipeshouldbelocatedon thesameside ofthe
roof. Both pipes must not be closer than 5
inches apart. They should not be separated
more than 36 inches.
The roof penetration must be properly flashed
and waterproofed with a plumbing roof boot or
equivalent flashing. Termination spacing re-
quirements from the roof and from each other
must be per Figure 20.
Concentric Vent Termination
A concentric vent termination is approved for
use with these furnaces (See Table 12). For
proper installation of the concentric vent termi-
nation, follow the installation instructions pro-
vided with the kit.

19
36" max.
12" min.
ExhaustVent
Option B
ExhaustVent
Option A
ExhaustVent
Option C
Mounting Kit
Faceplate Secured
toWall with Screws 12" Min.
36" Max.
12" Min.
36" Max.
7" Min.
8" Min.
12" Min. to
Normal Snow Level
Combustion
Air Inlet
Grade
Level
or Normal
Snow
Inlet Exhaust
Figure 20. Vertical Vent Termination
A= 12" Above Roof or
Snow Accumulation Level
Figure 19. Exhaust and Combustion Air
Pipe Clearances
Elbow
Exhaust
Vent
Exhaust
PlumbingVent
Roof Boot
(Typ. Both Pipes)
A
1"
5" Min.
36" Max.
10" Min.
Combustion
Air Intake
Figure 18. Alternate Horizontal
Vent Installation
Outside
Wall Support
Vent Configuration to
Provide 12" Minimum
height above
Snow Level.
1/2"
Armaflex
Insulation or
Equivalent
(if required)
12" Above
Normally
Expected
Snow
Level
12" Min.
19" Max.
DRAINAGEOFCONDENSATE
FROMFURNACE
!WARNING:
Thecondensateproducedbythefurnace
mustbedrained.Donotconnectawater
supply to the drainage hose of the
furnace.
NOTE: The condensate drain should be pro-
tected from freezing when in unheated spaces.
Thefurnaceissuppliedwithaninternalconden-
sate drain trap.
!CAUTION:
Do not install additional traps in the
condensate drain.
The condensate drain may exit through the left
side panel, the right side panel, or through the
leftorrightholeonthebottompanel.(SeeFigure
21). Ensure that the flexible drain hose is not
kinked.
The condensate should drain from the plastic
collector box (location A in Figure 21) as drop-
lets or a small stream. If you notice the furnace
has operated for more than 5 minutes without
draining or the red status light on the control
board is pulsing a 2-blink code follow the steps
below.
Note: If terminations meet-
ing these vertical require-
mentsexceedthemaximum
height for safe transit, the
vent and combustion air in-
takes may be shipped with
the home for assembly on
site. The furnace must be
labeledtonotifytheinstaller/
user not to use the furnace
until the vent and combus-
tion air intake terminations
are installed.

20
Figure 21. Furnace with Condensate Drain Trap Assembly
A
A
Clamp
Step 1: Loosen
Step 2: Rotate to drain direction
Step 3: Retighten
Keep
Downward
Slope
Alt. Drain
Alt. Drain
Alt. Drain
Alt. Drain
Floor Cavity
Floor
“Hard”
J DrainTube
Burner
Box
Collector
Box
1. Remove the collector box soft tube at
location A in Figure 21 and insure the exit
from the collector box is clear of any
debris or obstructions.
2. Replace this tube and insure the fit to the
headerspoutisairtight.Airwillbedrawninto
the header if this connection is not tight.
3. Check other tube connections along the
drain system. Insure that all are air tight.
NOTE: Industry research studies indicate that
when condensate is routed to an active drain,
household detergents, etc., buffer its acidity. If
thedrainisnot actively usedorifcodes require,
obtain a neutralizer kit (See Table 12). Proper
drains and connections to the condensate tub-
ing are required as NORDYNE cannot be held
responsible for water leakage which occurs
due to loose hose connections or improperly
sealed drain line pipes.
GAS SUPPLY AND PIPING
General
This furnace is equipped for bottom, left, or
right side gas entry. Typical gas service hook-
ups are shown in Figure 22. When making the
gas connection provide clearance between the
gassupplylineandtheentryholeinthefurnace
casingtoavoid unwantednoiseand/ordamage
to the furnace.
All gas piping must be installed in compliance
with local codes and utility regulations. Some
localregulationsrequiretheinstallationofamanual
mainshut-offvalveandgroundjointunionexter-
nal to the furnace. The shut-off valve should be
readily accessible for service and/or emer-
gency use. Consult the local utility or gas
supplier for additional requirements regarding
placement of the manual main gas shut-off. In
the absence of local codes, the gas line instal-
lation must comply with the provisions stated in
the Federal Manufactured Home Standard
(H.U.D Title 24, part 280) and the National Fuel
Gas Code (ANSI Z223.1/NFPA-54) or (CAN/
CGA B149) installation codes.
Adriplegshouldbeinstalled in the vertical pipe
run to the unit. Table 7 lists gas flow capacities
for standard pipe sizes as a function of length
in typical applications based on nominal pres-
sure drop in the line.
NOTE:Gaspipingmustnotberuninorthrough
air ducts, gas vents, etc.
Compounds used on threaded joints of gas
piping must be resistant to the actions of lique-
fied petroleum gases.
!CAUTION:
Do not use matches, lighters, candles,
orothersourcesofopenflametocheck
for gas leaks.
NOTE: When pressure testing gas supply
lines at pressures greater than 1/2 psig (14 in.
water column), the furnace must be discon-
nected from the gas supply piping system to
preventdamagetothegascontrolvalve.