Nordyne RA 80+ series User manual

Installation Instructions
These instructions are
primarily intended to
assist qualified individuals
experienced in the proper
installation of this type
appliance. Some local
codes require licensed
installation/service
personnel for this type
of equipment. Read all
instructions carefully
before starting the
installation.
*RA 80+ Series
High Efficiency Compact Upflow/Horizontal
Residential Gas Furnaces
!
WARNING:
If the information in these
instructions is not followed
exactly, a fire or explosion may
result, causing property damage,
personal injury or death.
Do not store or use gasoline or
other flammable vapors and
liquids in the vicinity of this or
any other appliance.
WHAT TO DO IF YOU SMELL
GAS:
• Donottrytolightanyappliance.
• Do not touch any electrical
switch;donotuseanyphonein
your building.
• Immediately call your gas
supplier from a neighbor's
phone.Followthegassupplier's
instructions.
• If you cannot reach your gas
supplier,callthefiredepartment.
• Extinguish any open flame.
FORYOUR SAFETY
!
WARNING:
Improperinstallation,adjustment,
alteration, service, or
maintenance can cause injury or
property damage. Refer to this
manual for assistance. For
additional information consult a
qualifiedinstaller,serviceagency,
or the gas supplier.

2
Table of Contents
Furnace Specifications ............................................................................................................. 3
Safety Information............................................................................................................. 3
Capacities-Furnace Airflow Data ..................................................................................... 4
Installation Requirements........................................................................................................ 5
Horizontal Furnace Installation ........................................................................................ 5
Venting and Combustion Air Requirements ....................................................................... 7
General ............................................................................................................................. 7
Installation in an Unconfined Space ................................................................................. 7
Installation in a Confined Space ....................................................................................... 8
Air From Inside ....................................................................................................... 8
Outdoor Air Using Vertical Ducts .......................................................................... 9
Air Directly Through an Exterior Wall .................................................................... 9
Outdoor Air Using a Crawl Space and Ventilated Attic ......................................... 9
Outdoor Air Using Horizontal Ducts ...................................................................... 9
Venting Requirements .............................................................................................................. 9
General ............................................................................................................................. 9
Category I - Common Venting .......................................................................................10
Circulating Air Supply ............................................................................................................ 11
General ...........................................................................................................................11
Return Air ........................................................................................................................12
Gas Supply and Piping ...........................................................................................................12
General ...........................................................................................................................13
Leak Check ....................................................................................................................13
Conversion .....................................................................................................................15
High Altitude Conversion ...................................................................................................... 15
High Altitude Application .................................................................................................15
Pressure Switch Conversion for High Altitude Applications .........................................15
Natural Gas High Altitude Conversion ...........................................................................15
LP/Propane Gas Sea Level and High Altitude Conversion ...........................................15
Electrical Wiring ....................................................................................................................... 16
General ...........................................................................................................................16
Line Voltage Wiring ......................................................................................................... 16
Low Voltage Wiring .........................................................................................................18
Start-up and Adjustments ..................................................................................................... 18
General ...........................................................................................................................18
Start-up Procedures .......................................................................................................19
Verifying and Adjusting Firing Rate ................................................................................19
Verifying and Adjusting Temperature Rise ....................................................................21
Verifying Burner Operation............................................................................................. 21
Verifying Operation of the Supply Air Limit Switch ........................................................23
Wiring Diagram ........................................................................................................................ 20
Description of Components .................................................................................................. 23
Maintenance ............................................................................................................................. 23
Vent System ...................................................................................................................23
Air Filter(s) ......................................................................................................................24
Lubrication....................................................................................................................... 24
Blower Compartment ......................................................................................................24
Heat Exchanger and Burner Maintenance ....................................................................24
Cleaning of Flue Passages ............................................................................................24
Cleaning of Burners ........................................................................................................25
System Operation Information ............................................................................................. 25
General ...........................................................................................................................25
Sequence of Operation ..................................................................................................26
Heating Mode .......................................................................................................26
Cooling Mode........................................................................................................26
Fan Mode .............................................................................................................27
Furnace Fails to Operate ...............................................................................................27
Twinning ..........................................................................................................................27
Installation/Performance Check List ..................................................................... Back Page

3
FURNACE SPECIFICATIONS - Upflow/Horizontal Models
Table 1. Furnace Dimensions and Shipping Weights
Figure 1. Unit Dimensions in Inches
Note:†CanbeCorN
3-15/16
27-3/4
24-3/4
19-3/4
25-3/4
22-13/16 1-9/16
3-1/2
30-1/2
25-1/8
23
1-1/4 23
7/8
15
C
B
A
34-5/8
27-7/8
23
3-1/2
1-9/16
22-13/16
25-3/4
7/8
D23
Bottom Return
(Bottom Return Opening)
SAFETYINFORMATION
1. Use only with type of gas approved for this
furnace. Refer to the furnace rating plate.
2. Install this furnace only in a location and
position as specified on Table 3 of these
instructions.
3. Provide adequate combustion and
ventilation air to the furnace space as
specified on Pages 8 through 12.
4. Combustion products must be discharged
outdoors. Connect this furnace to an
approved vent system only, as specified
on Pages 9 through 11.
5. Never test for gas leaks with an open
flame. Use a commercially available soap
solutionmadespecifically for thedetection
of leaks to check all connections, as
specified on Page 14 of these instructions.
6. Always install furnaceto operate withinthe
furnace’s intended temperature-rise range
with a duct system which has an external
static pressure within the allowable range,
as specified on Table 2 of these
instructions. 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
Model Furnace Dimensions Shipping
NumberInputABCDFlueOutletWeight
*RA- (Btuh) (in.) (in.) (in.) (in.) (in.) (lbs)
045(†)-08A 45,000 14 1/4 12 3/4 4 11 3/4 4 88
054(†)-12A 54,000 14 1/4 12 3/4 4 11 3/4 4 94
072(†)-12A 72,000 14 1/4 12 3/4 4 11 3/4 4 96
072(†)-12B 72,000 19 3/4 18 1/4 7 5/8 17 1/4 4 108
072(†)-16B 72,000 19 3/4 18 1/4 7 5/8 17 1/4 4 115
090(†)-12B 90,000 19 3/4 18 1/4 7 5/8 17 1/4 4 115
090(†)-16B 90,000 19 3/4 18 1/4 7 5/8 17 1/4 4 120
090(†)-20B 90,000 19 3/4 18 1/4 7 5/8 17 1/4 4 130
108(†)-16B 108,000 19 3/4 18 1/4 7 5/8 17 1/4 4 125
108(†)-20B 108,000 19 3/4 18 1/4 7 5/8 17 1/4 4 130
108(†)-20C 108,000 22 1/2 21 9 20 4 135
126(†)-20C 126,000 22 1/2 21 9 20 4 137
FURNACE DIMENSIONS AND SHIPPING WEIGHTS

4
CAPACITIES—FurnaceAirflowData
Table 2. Furnace Airflow Data
* Factory Set Cooling Speed ** Factory Set Heating Speed Notes: 1. Airflow rates of 1800 CFM or more require two return air connections. Data is for operation with filter(s).
2. Temperature rises in the table are approximate. Actual temperature rises may vary. 3. Temperature rises displayed in italics are for reference only. 4. Temperature rises displayed in BOLD are rated temperature rises.
CFM Rise CFM Rise CFM Rise CFM Rise CFM Rise CFM Rise CFM Rise CFM Rise
1000 33 970 34 950 35 920 36 870 38 820 41 770 43 700 47
760 43 740 44 730 45 720 46 690 48 670 49 640 52 620 53
1300 31 1260 32 1210 33 1160 34 1110 35 1050 38 980 40 910 44 1150 34 1120 35 1090 36 1050 38 1000 40 950 42 890 44 830 48
790 50 780 50 770 51 750 53 720 55 690 57 650 61 600 66
1380 38 1350 39 1310 40 1260 42 1210 44 1150 46 1080 49 1000 53
1220 43 1190 44 1160 45 1120 47 1070 49 1020 52 950 55 880 60
820 64 800 66 780 68 760 69 730 73 700 76 670 79 640 83
1550 34 1500 35 1440 37 1360 40 1280 42 1190 45 1080 49 970 55
1380 41 1310 41 1240 44 1200 44 1140 47 1090 49 970 55 870 61
1030 52 1030 52 1010 53 980 54 930 57 860 62 780 69 670 80
1955 26 1945 27 1920 27 1890 28 1845 29 1785 30 1700 31 1605 33 1635 32 1615 33 1590 33 1570 34 1550 35 1500 36 1440 37 1370 40 1370 40 1365 40 1350 40 1340 41 1305 42 1270 43 1230 44 1150 46
1165 46 1160 46 1150 46 1130 47 1110 48 1075 49 1030 51 975 55
1550 42 1500 44 1440 46 1360 48 1280 51 1190 55 1080 61 970 68
1380 52 1310 55 1240 58 1200 55 1140 58 1090 64 970 68 870 76
1030 64 1030 64 1010 65 980 67 930 72 860 78 780 85 670 99
1985 33 1955 34 1905 35 1855 36 1790 37 1705 40 1630 41 1530 44
1635 41 1640 41 1610 42 1575 42 1545 43 1490 45 1430 47 1350 49
1410 47 1400 47 1380 48 1355 49 1320 50 1290 52 1240 54 1175 57
1210 55 1195 55 1180 56 1160 57 1135 59 1100 60 1060 63 1010 66
2375 28 2320 29 2280 30 2215 30 2150 31 2085 32 2015 33 1940 34 1975 33 1955 34 1920 35 1895 35 1850 36 1800 37 1740 38 1685 39 1640 40 1615 41 1595 41 1575 42 1540 43 1500 44 1460 46 1400 48
1365 49 1345 50 1330 50 1315 51 1280 52 1245 53 1225 54 1210 55
1985 40 1955 41 1905 42 1855 43 1790 45 1705 47 1630 49 1530 52
1635 49 1640 49 1610 50 1575 51 1545 52 1490 54 1430 56 1350 59
1410 57 1400 57 1380 58 1355 59 1320 60 1290 62 1240 65 1175 68
1210 66 1195 67 1180 68 1160 69 1135 70 1100 73 1060 75 1010 79
2410 32 2370 33 2330 34 2275 35 2230 36 2165 37 2075 38 1990 40 2035 39 1995 40 1965 41 1955 41 1915 42 1895 42 1815 44 1790 45
1680 47 1660 48 1650 49 1645 49 1640 50 1565 51 1550 52 1485 54
1435 55 1430 55 1425 56 1415 56 1400 57 1350 59 1330 60 1275 62
2270 35 2210 36 2190 36 2165 37 2130 38 2100 39 2030 40 1975 41 1880 42 1865 43 1835 43 1815 44 1790 45 1770 45 1755 46 1720 47
1565 50 1550 51 1535 52 1520 52 1510 53 1495 54 1455 55 1420 56
1325 60 1320 61 1315 61 1310 61 1285 62 1275 63 1250 64 1220 66
2270 40 2210 41 2190 42 2165 43 2130 44 2100 45 2030 46 1975 47
1880 49 1865 50 1835 51 1815 51 1790 52 1770 52 1755 53 1720 54
1565 59 1550 60 1535 61 1520 61 1510 62 1495 63 1455 64 1420 66
1325 70 1320 70 1315 71 1310 71 1285 72 1275 73 1250 75 1220 76
EXTERNAL STATIC PRESSURE
(
INCHES OF WATER COLUMN
)
0.10.20.30.40.50.60.7 0.8
MODEL
NUMBER HEATING MOTOR MOTOR
*RA INPUT SPEED HP
045-08A 40,000 HIGH* 1/5
LOW**
054-12A HIGH*
54,000 MEDIUM 1/3
LOW**
072-12A HIGH*
72,000 MEDIUM 1/3
LOW**
072-12B HIGH*
72,000 MEDIUM 1/4
LOW**
072-16B HIGH
72,000 MED-HIGH* 1/2
MED-LOW**
LOW
090-12B HIGH*
90,000 MEDIUM 1/4
LOW**
090-16B HIGH*
90,000 MED-HIGH** 1/2
MED-LOW
LOW
090-20B HIGH*
90,000 MED-HIGH 3/4
MED-LOW
LOW**
108-16B HIGH*
108,000 MED-HIGH** 1/2
MED-LOW
LOW
108-20B HIGH*
108,000 MED-HIGH 3/4
MED-LOW
LOW**
108-20C HIGH*
108,000 MED-HIGH** 3/4
MED-LOW
LOW
126-20C HIGH*
126,000 MED-HIGH** 3/4
MED-LOW
LOW

5
by duct(s) sealed to the furnace casing
and terminating outside the space
containing the furnace.
8. A gas-fired furnace for installation in a
residential garage must be installed as
specified on Page 7 of these instructions.
9. Thefurnaceisnottobeusedfortemporary
heating of buildings or structures under
construction.
INSTALLATIONREQUIREMENTS
Requirements and Codes
This furnace must be installed in accordance
withtheseinstructions,allapplicablelocalbuilding
codes, current revision of the National Fuel
Gas Code (ANSI-Z223.1), and in Canada with
the CAN/CGA - B149 installation code. The
current revision of the National Fuel Gas Code
is available from:
American National Standards Institute,
Inc.
1430 Broadway
New York, New York 10018
Additional helpful publications are:
NFPA-90A - Installation of
Air Conditioning and Ventilating Systems
NFPA-90B - Warm Air Heating
and Air Conditioning Systems
These publications are available from:
National Fire Protection Association, Inc.
Batterymarch Park
Quincy, Massachusetts 02269
!WARNING:
This furnace is not approved for
installationinmobilehomes. Installation
in a mobile home could cause fire,
property damage, and/or personal
injury.
Location
These gas furnaces are shipped ready for
installation in the upflow, horizontal right or left
positions. The furnace must be installed on a
level surface, located close to the vent (or
chimney) and as close to the center of the air
distributionsystemaspossible. SeeTable1 for
overall dimensions to determine the required
clearances in hallways, doorways, stairs, etc.
toallowthefurnacetobemovedtotheinstallation
point. The furnace must be installed so that all
electricalcomponentsareprotectedfromwater.
The furnace must be installed upstream from a
refrigeration system. This furnace is not to be
used for temporary heating of buildings or
structures under construction.
Horizontal Furnace Installation
The furnace can be installed horizontally in an
attic, basement, crawl space or alcove. It can
be suspended from a ceiling in a basement or
utilityroomineither arighttoleftairflowor leftto
right airflow. (See Figures 2 and 3.)
If the furnace is to be suspended from the
ceiling, it will be necessary to use steel straps
around each end of the furnace. These straps
should be attached to the furnace with sheet
metal screws and to the rafters with bolts. The
furnace could also be suspended by an angle
iron frame bolted to the rafters. (See Figure 2.)
Access for positioning and servicing must be
considered when locating the unit. Refer to
Table 3, Minimum Clearances to Combustible
Material, for clearance specifications.
Keep all insulating materials away from the
louvered door. Insulating materials may be
combustible.
These furnaces may be installed directly on
combustiblewoodflooringorsupports,iftype"B-
1" vent pipe is used (See Figure 3). It is
recommendedforfurtherreductionoffirehazard
that cement board or sheet metal be placed
between the furnace and the combustible floor
and extend 12 inches beyond the front of the
louvered door.
!WARNING:
Furnaces installed with combustion air
drawn from a heated space which
includes exhaust fans, fireplaces, or
other devices that may produce a
negativepressureshouldbeconsidered
confinedspaceinstallations.
See the "venting requirements" section for
venting guidelines and specifications.

6
Gas Inlet
Electrical
Supply
Connection
Coil Plenum
Type “B” Vent
Combustible
Platform
Louver Door
Note: Edge or Line
Contact is Permissible
Figure2.HorizontalInstallation
SuspendedinAtticorCrawlSpace Figure3.HorizontalInstallation
ona Platform
Upflow and Horizontal Furnaces
UPFLOWAPPLICATION
RIGHT
SIDE
BOTTOM
TOP
LEFT
SIDE
TOP
BOTTOM
SIDE
SIDE
HORIZONTALAPPLICATION
†Allow24"minimumclearanceforservicing.
Therecommendedclearanceis36".
Table 3. Minimum Clearances to Combustible Material
INSTALLATION CLEARANCES
Vent Connector
Type
Standard Single
Wall Metal Vent
Type B-1 Double
Wall Metal Vent
LEFT SIDE 0" 0"
RIGHT SIDE 0" 0"
VENT 6" 1"
BACK 0" 0"
BOTTOM 0" 0"
TOP 1" 1"
FRONT
4"
†
4"
†

7
VENTINGANDCOMBUSTION
AIRREQUIREMENTS
General
Provisionsmustbemadeintheinstallationofthis
furnace to provide an adequate supply of air for
combustion. Detailedinstructionsfordetermining
theadequacyofaninstallationcanbefoundinthe
current revision of the National Fuel Gas Code
(ANSI Z223.1 / NFPA54) or in applicable local
buildingcodes. Consultlocalcodesforspecial
Clearances to Combustibles
This furnace is Design Certified by CSA Inter-
national for the minimum clearances to com-
bustible material listed in Table 3. Refer to the
furnace rating plate, located inside of the fur-
nace cabinet, for the specific model number
and clearance information.
Access for positioning and servicing the unit
must be considered when locating unit. 24
inches is the minimum required clearance from
the front of the unit for servicing it. 30 inches is
the minimum required clearance from the front
of the unit for positioning it. 36 inches is the
recommended clearance from the front of
the unit. Please note that a panel or door can
belocatedsuch thattheminimum clearanceon
theratingplateissatisfied,butthatpanelordoor
must be removable and allow the appropriate
clearance for your installation.
Thisfurnaceiscertifiedforuseonwoodflooring.
This furnace must not be installed directly on
carpeting, tile, or any combustible material
other than wood flooring.
A gas-fired furnace installed in a residential
garagemustbeinstalledsotheburnersandthe
igniter are located not less than 18 inches (457
mm) above the floor, and the furnace must be
located or protected to avoid physical damage
by vehicles.
!WARNING:
Donotplace combustiblematerialon or
against the furnace cabinet or within 6
inchesoftheventpipe(forB-ventusethe
recommended clearance). Do not place
combustiblematerials,includinggasoline
and any other flammable vapors and
liquids,inthevicinityofthe furnace.
requirements.ForCanadianinstallationsconsult
Canadian Installations Codes and (CAN/CGA
B149.1 or .2).
If the furnace is operated with inadequate air for
combustion one of the flame roll-out switches
located in the burner compartment or the vent
switchwillopen,turningoffthegassupplytothe
burners. These safety devices are manually
reset switches. DO NOT install jumper wires
across these switches to defeat their function.
DO NOT reset a switch without identifying and
correctingthefaultcondition. Ifaswitchmustbe
replaced, use only the correct part specified in
the Replacement Parts List.
Air openings in the furnace door, supply air
registers, and return air grilles must not be
restricted.
!CAUTION:
Combustionairmustnotbedrawnfrom
a corrosive atmosphere.
Tomaximizeheatexchangerlife,thecombustion
air must be free of chemicals which form
corrosive acidic compounds in the combustion
gases. Some examples of these chemicals are
chlorine, fluorine, and sulphur. Some common
sources of these chemicals are detergents,
bleaches, aerosol sprays, cleaning solvents,
andawidevarietyofcommercialandhousehold
products.
Wheninstallingafurnaceinacommercialbuilding
orinalaundryroomorworkshopofaresidence,
it may be necessary to provide outside air to the
furnace for combustion.
!WARNING:
Furnace installation using methods
other than those described in the
following sections must comply with
the National Fuel Gas Code and all
applicable local codes to provide
sufficientcombustionairforthefurnace.
Installation In An Unconfined Space
An unconfined space is an area including all
rooms not separated by doors with a volume
greater than 50 cubic feet per 1,000 Btuh of the
combinedinputratesofallapplianceswhichdraw

8
Total Input
Rating (Btu/hr)
40,000
60,000
80,000
100,000
120,000
140,000
160,000
Minimum
Free Area
(Each Opening)
10 sq. in.
15 sq. in.
20 sq. in.
25 sq. in.
30 sq. in.
35 sq. in.
40 sq. in.
Round Duct
Diameter
4"
5"
5"
6"
6"
7"
8"
Inlet Air Duct must
be at least 1 sq. in.
per 4,000 Btuh of
total input rating.
Inlet and Outlet Ducts
must extend above
attic insulation.
Outlet Air Duct must
be at least 1 sq. in.
per 4,000 Btuh of
total input rating.
Ventilation Louvers at
each end of attic
Attic
Insulation
12" Max
a. All Combustion Air from Ventilated Attic.
Furnace
Water Heater
Vent or
Chimney
Figure 5. Equipment in a Confined Space with all
Combustion Air Drawn from the Outside
through Vertical Ducts
Air From Inside (See Figure 4)
If combustion air is taken from the heated
space, the two openings must
each have a free
area of at least one square inch per 1,000 Btuh
of total input of all appliances in the confined
space, but not less than 100 square inches
of free area. Forexample, ifthecombined input
rate of all appliances is less than or equal to
100,000 Btuh, each opening must have a free
area of at least 100 square inches. If the
combinedinput rate ofall appliancesis 126,000
Btuh, each opening must have a free area of at
least 126 square inches.
combustion air from that space. For example, a
space including a water heater rated at 45,000
Btuh input and a furnace rated at 72,000 Btuh
requires a volume of 5,850 cubic feet [50 x (45 +
72) = 5,850] to be considered unconfined. If the
space has an 8 foot ceiling, the floor area of the
space must be 731 square feet (5,850 / 8 = 731).
In general, a furnace installed in an unconfined
space will not require outside air for combustion.
However,in“tight”buildings(withweatherstripping
and caulk to reduce infiltration), it may be
necessary to provide outside air to ensure
adequate combustion and venting, even though
the furnace is located in an unconfined space.
Installation In A Confined Space
A confined space is an area with volume less
than 50 cubic feet per 1,000 Btuh of the
combined input rates of all appliances drawing
combustion air from that space. Furnace
closets, small equipment rooms and garages
are confined spaces. Furnaces installed in a
confined space which supply heated air to
areas outside the space must draw return air
from outside the space and must have the
return air ducts tightly sealed to the furnace. A
confined space must have two openings
into the space for combustion air. One
opening must be within 12 inches of the
ceiling, and the other must be within 12
inches of the floor. The required sizing of
theseopeningsisdeterminedbywhetherinside
or outside air is used to support combustion,
the method by which the air is brought to the
space,andbythetotalinputrateofallappliances
in the space.
Total Input
Rating (Btu/hr)
40,000
60,000
80,000
100,000
120,000
140,000
160,000
Round Duct
Diameter
12"
12"
12"
12"
13"
14"
15"
Minimum
Free Area
(Each Opening)
100 sq. in.
100 sq. in.
100 sq. in.
100 sq. in.
120 sq. in.
140 sq. in.
160 sq. in.
Furnace
Openings to
adjacent space.
Each opening must
be at least 100 sq. in.
or 1 sq. in. per 1000
Btuh of total input
rating, whichever is
greater. See minimum
area per table.
12" Max.
12" Max.
Water Heater
Vent or
Chimney
Figure 4. Equipment in a Confined Space with all
Combustion Air Drawn from the Inside
Figure6. Equipment in aConfined Space with all
CombustionAirDrawnfromtheOutsidethrough
Exterior Wall
Each opening
to outside
must be at least
1 sq. in. per 4000
Btuh of total input
rating.
12" Max
12" Max
Total Input
Rating (Btuh)
40,000
60,000
80,000
100,000
120,000
140,000
160,000
Minimum
Free Area
(Each Opening)
10 sq. in.
15 sq. in.
20 sq. in.
25 sq. in.
30 sq. in.
35 sq. in.
40 sq. in.
Round Duct
Diameter
4"
5"
5"
6"
6"
7"
8"
-
-
-
-
-
-
-
-
-
-
-
-
-
-
-
-
-
-
Furnace
Water Heater
Vent or
Chimney

9
Outdoor Air Using Vertical Ducts
(See Figure 5)
Ifcombustion airis takenfrom outdoorsthrough
vertical ducts, the openings and ducts must
haveaminimumfreeareaofonesquareinchper
4,000Btuhoftotalapplianceinput.Ininstallations
drawing combustion air from a ventilated attic,
both air ducts must extend above the attic
insulation.
If the unit is installed in an area with an exhaust
fan, provide sufficient ventilation to prevent
negative pressures from occurring in the room.
The combustion air openings must not be
restricted in any manner.
!CAUTION:
Do not supply combustion air from an
attic space that is equipped with power
ventilationoranyother device that may
produce a negative pressure.
Air Directly Through An Exterior Wall
(See Figure 6)
If combustion air is provided directly through an
exterior wall, the two openings must each have
free area of at least one square inch per 4000
Btuh of total appliance input.
OutdoorAirUsingaCrawlSpaceandVentilated
Attic (See Figure 7)
Whendirectlycommunicatingwiththeoutdoors,
eachopeningshallhaveaminimum freeareaof
1 square inch per 4,000 Btuh of total appliance
input.Theopeningsshallcommunicatedirectly,
or by ducts, with the outdoor spaces (crawl or
attic)thatfreelycommunicatewiththeoutdoors.
Outdoor Air Using Horizontal Ducts (See
Figure 8)
Ifcombustionair istakenfromoutdoors through
horizontal ducts, the openings and ducts must
have a minimum free area of one square inch
per 2,000 Btuh of total appliance input.
If the unit is installed in an area with an exhaust
fan, provide sufficient ventilation to prevent
negative pressures from occurring in the room.
The combustion air openings must not be
restricted in any manner.
VENTINGREQUIREMENTS
General
This furnace must be vented in compliance with,
the current revision of the National Fuel Gas
Code (ANSI-Z223.1/NFPA54), with the
instructions provided below. This furnace is
approved for Category I venting only.
In Canada, venting shall conform to the
requirements of the current (CAN/CGA B149.1
or .2) installation codes. Consult local codes
for special requirements.
This furnace must never be vented to a chimney
flue servicing a fireplace or other appliance
Figure 7. Equipment in a Confined Space with All
Combustion Air Drawn from a Crawl Space
and Ventilated Attic
Outlet Air Duct
must be at least
1 sq. in. per 4000
Btuh of total input
rating. Must extend
above attic insulation.
Ventilation Louvers at
each end of attic
Attic Insulation
Ventilation Louvers for
unheated crawl space Crawl Space
Inlet Air Duct must
be at least 1 sq. in.
per 4,000 Btuh of
total input rating.
Furnace
Water Heater
Vent or
Chimney
Figure8. Equipment in aConfined Space with all
CombustionAirDrawnfromtheOutsidethrough
HorizontalDucts
Each opening
to outside
must be at least
1 sq. in. per 2000
Btuh of total input
rating.
12" Max
12" Max
Total Input
Rating (Btu/hr)
40,000
60,000
80,000
100,000
120,000
140,000
160,000
Minimum
Free Area
(Each Opening)
20 sq. in.
30 sq. in.
40 sq. in.
50 sq. in.
60 sq. in.
70 sq. in.
80 sq. in.
Round Duct
Diameter
5"
6"
7"
8"
9"
10"
10"
-
-
-
-
-
-
-
-
-
-
-
-
-
-
-
-
-
-
Furnace
Air Duct
Air Duct
Water Heater
Vent or
Chimney
-
-
-
-
-
-
-
-
-
-
-
-
-
-
-
-
-
-

10
designed to burn solid fuel. If the furnace vent is
tobeconnectedtoachimneyservingafireplace,
thefireplacemustbesealedofffromthechimney.
Single wall metal vents shall not be used for
Category I venting. Category I furnaces
must be vented vertically or near vertically.
ForCategory I furnaceinstallations, thefurnace
shall be connected to a factory built chimney or
vent complying with a recognized standard, or
a masonry or concrete chimney lined with a
liningmaterialacceptabletotheauthorityhaving
jurisdiction. Venting into an unlined masonry
chimney or concrete chimney is prohibited.
The furnace vent, if metal, may be insulated if
local codes allow. Any part of the vent system,
metal vent only, not exposed to weather, but
which are exposed to ambient temperatures
below 35° F must be insulated to prevent
condensation. All vent insulation shall be foil
backed fiberglass of one inch minimum
thickness.
Three sheet metal fasteners (field supplied)
should be used to secure the vent pipe to the
furnace flue. These fasteners should be evenly
spaced around the flue diameter, if possible.
Combustion Air Quality
The recommended source of combustion air is
to use the outdoor air supply. However, the use
of indoor air in most applications is acceptable
except as follows:
1. If the furnace is installed in a confined
spaceitisrecommendedthatthenecessary
combustion air come from the outdoors by
way of attic, crawl space, air duct, or direct
opening.
2. If outdoor combustion air is used, there
must be no exposure to the installations or
substances listed in Item 3 below.
3. The following types of installation may
require Outdoor Air for combustion, due
to chemical exposures:
• Commercial buildings
• Buildings with indoor pools
• Furnaces installed in laundry rooms
• Furnaces installed in hobby or craft
rooms
• Furnacesinstallednearchemicalstorage
areas
Exposure to the following substances in
thecombustionairsupplymayalsorequire
Outdoor Air for combustion:
• Permanent wave solutions
• Chlorinated waxes and cleaners
• Chlorine based swimming pool
chemicals
• Water softening chemicals
• De-icing salts or chemicals
• Carbon tetrachloride
• Halogen type refrigerants
• Cleaning solvents (such as
perchloroethylene)
• Printinginks,paint removers,varnishes,
etc.
• Hydrochloric acid
• Cements and glues
• Antistatic fabric softeners for clothes
dryers
• Masonry acid washing materials
Category I - Common Venting
When an existing furnace is removed from a
venting system serving other appliances, the
venting system is likely to be too large to properly
vent the remaining appliances. An improperly
sized venting system can result in the formation
of condensate, leakage, spillage, etc.
Theventingsystemshouldbedesignedtohave
the minimum number of elbows or turns. All
horizontal runs shall be sloped upwards from
the furnace at 1/4 inch per running foot of vent.
Supports for the vent pipe must be installed a
minimum of every five feet along the vent run to
ensure no displacement after installation.
Undernocircumstances shallany portion ofthe
vent system extend into or pass through any
return air duct, supply air duct, or plenum.
Ifthefurnaceisoperatedwithblockedorrestricted
venting, the burner roll-out limit switch will open,
turningoffthegassupplytotheburners. Theroll-
out limit switch is a manually reset device. DO
NOT install a jumper wire across this switch to
defeat its function. DO NOT reset the switch
without identifying and correcting the fault
condition which caused the switch to trip. If this
switch must be replaced, use only factory-
approved replacement parts.
!WARNING:
Upon completion of the furnace
installation, carefully inspect the entire
fluesystembothinside and outside the
furnace to assure it is properly sealed.
Leaks in the flue system can result in
serious personal injury or death due to
exposure of flue products, including
carbonmonoxide.

11
CIRCULATINGAIRSUPPLY
General
Plenums and air ducts must be installed in
accordancewiththeStandardfortheInstallation
of Air Conditioning and Ventilating Systems
(NFPANo.90A)ortheStandardfortheInstallation
of Warm Air Heating and Air Conditioning
Systems (NFPA No. 90B).
Itisrecommendedthattheoutletductbeprovided
with a removable access panel. This opening
should be accessible when the furnace is
installed in service and shall be of a size that
smokeor reflectedlight maybeobserved inside
the casing to indicate the presence of leaks in
the heat exchanger. The cover for the opening
shallbeattachedinsuchamannerastoprevent
leaks.
!
WARNING:
CARBON MONOXIDE POISONING HAZARD
Failure to follow the steps outlined below for each appliance connected to
the venting system being placed into operation could result in carbon
monoxidepoisoningordeath.
The following steps shall be followed for each appliance connected to the
venting system being placed into operation, while all other appliances
connected to the venting system are not in operation:
1. Seal any unused openings in the venting system.
2. Inspecttheventingsystemfor propersize andhorizontal pitch,as
required in the
National Fuel Gas Code, ANSI Z223. 1/NFPA 54 or
the CSA B149.1, Natural Gas and Propane Installation Codes
and
these instructions. Determine that there is no blockage or
restriction,leakage, corrosionand otherdeficiencies whichcould
cause an unsafe condition.
3. As far as practical, close all building doors and windows and all
doors between the space in which the appliance(s) connected to
the venting system are located and other spaces of the building.
4. Close fireplace dampers.
5. Turn on clothes dryers and any appliance not connected to the
venting system. Turn on any exhaust fans, such as range hoods
andbathroom exhausts,so theyare operatingat maximumspeed.
Do not operate a summer exhaust fan.
6. Followthelightinginstructions.Placetheappliancebeinginspected
into operation. Adjust the thermostat so appliance is operating
continuously.
7. Test for spillage from draft hood equipped appliances at the draft
hood relief opening after 5 minutes of main burner operation. Use
the flame of a match or candle.
8. If improper venting is observed during any of the above tests, the
ventingsystemmustbecorrectedinaccordancewiththe
National
Fuel Gas Code, ANSI Z223.1/NFPA 54 and/or CSA B149.1, Natural
Gas 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-fired burning appliance to their previous conditions of
use.

12
If outside air is used as return air to the furnace
forventilationortoimproveindoorairquality,the
system must be designed so that the return air
is not less than 50° F (10° C) during operation.
Ifacombinationofindoorandoutdoorairisused,
theductsanddampersystemmustbedesigned
so that the return air supply to the furnace is
equal to the return air supply under normal,
indoor return air applications.
When a cooling system is installed which uses
the furnace blower to provide airflow over the
indoorcoil,thecoilmustbeinstalleddownstream
(on the outlet side) of the furnace or in parallel
with the furnace.
Ifacoolingsystemisinstalledinparallelwiththe
furnace, a damper must be installed to prevent
chilled air from entering the furnace and
condensingontheheatexchanger. Ifamanually
operateddamperisinstalled,itmustbedesigned
so that operation of the furnace is prevented
when the damper is in the cooling position and
operation of the cooling system is prevented
when the damper is in the heating position.
Return Air
In applications where the supply ducts carry
heated air to areas outside the space in which
the furnace is installed, the return air must be
delivered to the furnace by duct(s) sealed to the
furnace casing, running full size and without
interruption.
!WARNING:
Thesolidbaseofthesefurnacesmustbe
inplacewhenthefurnaceisinstalledwith
sidereturnairducts.Removalofallorpart
of the base could cause products of
combustiontobecirculatedintotheliving
space and create potentially hazardous
conditions, including carbon monoxide
poisoning that could result in personal
injury or death.
The return air ductwork may be connected to
any or all of the following: left side return, right
side return, or bottom return. NOTE: Do not
use the back of the furnace for return air.
Table 2, in the front pages of these instructions,
containstheairflowdataforeachfurnacemodel.
Where maximum airflow is 1800 CFM or more,
two openings must be used for return air.
!WARNING:
Products of combustion must not be
allowed to enter the return air ductwork
or the circulating air supply. Failure to
prevent products of combustion from
beingcirculatedintothelivingspacecan
createpotentiallyhazardousconditions
including carbon monoxide poisoning
that could result in personal injury or
death.
All return ductwork must be secured to
thefurnacewithsheetmetalscrews.For
installationsinconfinedspaces,allreturn
ductwork must be adequately sealed
andjointsmustbetaped. Whenreturnair
is provided through the bottom of the
furnace, the joint between the furnace
and the return air plenum must be air
tight.
Thefloororplatformonwhichthefurnace
ismountedmustprovidesoundphysical
support of the furnace with no gaps,
cracks,orsagging betweenthefurnace
and the floor or platform.
Return air and circulating air ductwork
mustnotbeconnectedtoanyotherheat
producing device such as a fireplace
insert,stove,etc. Doingsomayresultin
fire, explosion, carbon monoxide
poisoning, personal injury, or property
damage.
GAS SUPPLY AND PIPING
!CAUTION:
Do not re-drill the burner orifices. If the
orifice size must be changed, use only
neworifices.

13
General
Thisfurnacemaybeinstalledforeitherleftorright
side gas entry. A typical gas service hookup is
shown in Figure 9. When making the gas
connection provide clearance between the gas
supplylineandtheentryholeinthefurnacecasing
to avoid unwanted noise and/or damage to the
furnace.
All gas piping must be installed in compliance with
local codes and utility regulations. Some local
regulationsrequirethe installationofa manualmain
shut-off valve and ground joint union external to the
Typical Right Side Entry
furnace. The shut-off valve should be readily
accessible for service and/or emergency use.
Consult the local utility or gas supplier for additional
requirements regarding placement of the manual
maingasshut-off.Inthe absenceoflocal codesthe
gaslineinstallationmustcomplywiththelatestedition
of the National Fuel Gas Code (ANSI Z223.1) or
(CAN/CGA B149.1 or .2) Installation Codes.
An1/8inch NPTtap mustbeinstalledinthegas
line to the unit for use when measuring the gas
supply pressure. The tap should be readily
accessible for service use. A drip leg should be
installedintheverticalpiperuntotheunit. Table
4 lists gas flow capacities for standard pipe
sizesasafunctionoflengthintypicalapplications
based on nominal pressure drop in the line.
IMPORTANT NOTES:
1. Gaspipingmustnot beruninorthroughair
ducts, chimneys, gas vents, elevator
shafts, etc.
2. Compoundsusedonthreadedjointsofgas
piping must be resistant to the actions of
liquefied petroleum gases.
3. Themain manual gasvalve and mainpower
disconnect to the furnace must be properly
labeled by the installer in case emergency
shutdown is required.
Leak Check
After the gas piping to the furnace is complete,
allconnectionsmust betestedforgas leaks. To
check for leaks in gas piping systems, use only
a soap and water solution or other approved
method.
!CAUTION:
Donotusematches,lighters,candles,or
othersourcesofopen flame to check for
gas leaks.
IMPORTANT NOTE:
When pressure testing the gas supply lines
at pressures greater than 1/2 psig (14 inch
W.C.), the furnace must be disconnected
fromthegas supply piping systemtoprevent
damage to the gas control valve. If the test
pressure is less than or equal to 1/2 psig (14
inch W.C.), the furnace must be isolated
from the gas supply line by closing the
manual shut-off valve.
Table 4. Capacity of Black Iron Gas Pipe
(cu. ft. per hour) for Natural Gas
(specific gravity = .60)
NOMINAL LENGTH OF PIPE RUN
BLACK IRON (feet)
PIPE DIAMETER
(in.) 1020304050607080
1
/
2 130 90 75 65 55 50 45 40
3/4
280
190
150
130
115
105
95
90
1
520
350
285
245
215
195
180
170
1
1/4
1050
730
590
500
440
400
370
350
1
1/2
1600
1100
890
760
670
610
560
530
The cubic feet per hour listed in the table above must be greater than the cubic feet
per hour of gas flow required by the furnace.
To determine the cubic feet per hour of gas flow required by the furnace, divide the
input rate of the furnace by the heating value of the gas:
Cubic Feet Per Hour Required Input To Furnace (Btu/hr)
Heating Value of Gas (Btu/Cu. Ft.)
CAPACITY OF BLACK IRON GAS PIPE (CU. FT. PER HOUR)
FOR NATURAL GAS (SPECIFIC GRAVITY - 0.60)
Figure9. TypicalGasServiceConnection
Ground Joint
Union
Dripleg
Shut-Off Valve
Burner
Assembly
Manifold
Some utilities
require Shut-Off
Valve to be
4 to 5 feet
above floor
Automatic Gas
Valve (with manual
shut-off)

14
Furnace Rating
Plate Input ##
(Btu/h) Nat LP
45,000 50 57
54,000 47 56
72,000 47 56
90,000 47 56
108,000 47 56
126,000 47 56
Orifice Drill Size
Table6.ManifoldPressure (inWC)forLP/PropaneGasat VariousAltitudes
Elevation
(
feet above sea level
)
0 to 2,000 to 5,000 to 6,000 to 8,000 to
1,999 4,999 5,999 7,999 10,000
10.0 8.5 10.0 9.0 8.5
ManifoldPressure in(WC)
for an LP Gas Heating
Value of 2,500 Btu/hr.
Table5. Manifold Pressure(in WC) for Natural Gasat Various Altitudes
For a Natural Gas Sea Level Heating Value of 800 to 899 Btu/cu.ft.
Elevation (feet above sea level)
zero to
1999 2000 to 4999 5000 to 5999 6000 to 7999 8000 to 10000
Manifold Pressure Setting (in WC) 3.5 3.5 3.5 3.5 3.0
For a Natural Gas Sea Level Heating Value of 900 to 999 Btu/cu.ft.
Elevation (feet above sea level)
zero to
1999 2000 to 4999 5000 to 5999 6000 to 7999 8000 to 10000
Manifold Pressure Setting (in WC) 3.5 3.5 3.5 3.2 2.8
For a Natural Gas Sea Level Heating Value of 1,000 to 1,100 Btu/cu.ft.
Elevation (feet above sea level)
zero to
1999 2000 to 4999 5000 to 5999 6000 to 7999 8000 to 10000
Manifold Pressure Setting (in WC) 3.5 3.5 3.0 2.8 2.5
Table 7. Natural and LP Gas Orifice
Sizes for Elevations between zero
and 4999 ft. Above Sea Level
Table 8. Natural and LP gas Orifice
Sizes for Elevations between 5000
and 10,000 ft. Above Sea Level
Furnace Rating
Plate Input ##
(Btu/h) Nat LP
45,000 50 61
54,000 47 61
72,000 47 61
90,000 47 61
108,000 47 61
126,000 47 61
Orifice Drill Size

15
!WARNING:
FIRE OR EXPLOSION HAZARD
Failuretofollowthesafetywarningsexactly
could result in serious injury, death or
property damage.
Never test for gas leaks with an open
flame.Useacommerciallyavailablesoap
solutionmadespecificallyforthedetection
ofleakstocheckallconnections.Afireor
explosion may result causing property
damage, personal injury or loss of life.
Conversion
Conversion of this furnace to use LP/propane
gas must be made by qualified service
personnel, using only approved parts.
!WARNING:
Thisfurnacewasequippedatthefactory
for use with natural gas only. A special
kit, supplied by the manufacturer, is
requiredtoconvertthefurnacetooperate
on LP/propane gas. Failure to use the
proper conversion kit can cause fire,
explosion, property damage, carbon
monoxidepoisoning,personalinjury,or
death.
HIGHALTITUDECONVERSION
High Altitude Application
Conversionofthisfurnacetoreplacethepressure
switch or to utilize LP/propane gas must be made
by qualified service personnel, using factory
authorized or approved parts. High altitude
applicationwiththisfurnacecanbefieldperformed
by a simple adjustment of manifold pressure, and
ifnecessarychangingtheorificesandthepressure
switch. The changes required depend on the
installation altitude and the heating value of the
gas.Thegasheatingvaluebasedonsealevelcan
beobtainedfromyour localgasutility.Theheating
value of gas at high altitude is always lower than
the sea level heating value. The heating values
usedinTables5&6arebasedonsealevelvalues.
Pressure Switch Conversion for High
Altitude Applications
The pressure switch is factory equipped to oper-
ate between zero and 5000 feet above sea level.
For higher altitude applications, you may need to
replace the pressure switch. The approved high
altitude pressure switch kit is 903853. The
directionstoconvertthefurnacearegivenbelow:
1. READ ALL INSTRUCTIONS BEFORE
PROCEEDINGWITHTHECONVERSION.
2. Disconnect all electrical power to the
furnace.
3. Remove the access door(s) from the front
of the unit.
4. TurnthegasvalveknobtotheOFFposition.
5. Shut off the gas to the unit.
6. Disconnect the electrical leads to the
pressure switch (see Figure 14). It is not
necessary to mark the leads as polarity
does not matter across the switch.
7. Remove the hose from the pressure switch
and remove the fasteners that secure the
pressure switch to the burner box.
8. Discard the old pressure switch.
9. From the kit, install the new high altitude
pressure switch using the same fasteners
that were removed above.
10. Reattach the hose to the pressure switch
portinthesamemannerasitwasremoved.
11. Reattach the electrical leads to the
pressure switch.
12. Turn on the electrical power to the furnace.
13. Turnthe gas valveknob tothe ONposition.
14. Followthe start-upprocedureoutlined later
intheseinstallationinstructions. Verifythat
the furnace is operating properly after the
conversion.
Natural Gas High Altitude Conversion
Allfactoryshippedfurnaces arereadytooperate
up to 4999 ft. above sea level. For higher
altitudes (between 5000 and 10,000 ft. above
sea level), conversion can be achieved simply
by adjusting the furnace manifold pressure as
shown in Table 5.
LP/Propane Gas Sea Level and High
Altitude Conversion
IMPORTANT NOTE:
When converting a low NOx Furnace from
NaturalgastoLP/Propanegas,itisnecessary
to remove the NOx Baffles.
Conversion to LP/propane gas can be
accomplished by first replacing the natural gas
orifices with the appropriate LP/propane orifices
shown in Table 7 or 8. Note: for installations
between zero and 5000 ft., refer to Table 7. For
installations above 5000 ft. above sea level,
refer to Table 8. After changing the orifices, use
Table 6 to determine the appropriate manifold
pressure for your installation.

16
Conversion to LP/propane, sea level, and high
altitudeisdetailed intheinstallationinstructions
provided with the conversion kit. Approved
conversion kits are listed below.
United States LP/Propane Gas Sea Level and
High Altitude Conversion Kit - P/N 904090
This kit is for LP/propane conversion in the
United States at altitudes between zero and
10,000ft.abovesealevel. Followtheinstallation
instructions supplied with the kit for proper
installation.
Canadian LP/Propane Gas Sea Level and High
Altitude Conversion Kit - P/N 904091
ThiskitisforLP/propaneconversionsinCanada
ataltitudesbetweenzeroand4500ft.abovesea
level.Followtheinstallationinstructionssupplied
with the kit for proper installation.
!CAUTION:
To avoid electric shock, personal
injury, or death, turn off the electric
power at the disconnect or the main
service panel before making any
electrical connections.
ELECTRICALWIRING
General
Electrical connections must be made in
accordance with all applicable local codes and
ordinances, and with the current revision of the
National Electric Code (ANSI/NFPA 70).
For Canadian installations the electrical
connections and grounding shall be done in
accordancewiththecurrentCanadianElectrical
Code (CSA C22.1, Part 1 and/or local codes).
If any of the original wire as supplied with the
furnace must be replaced, it must be replaced
with wire having a temperature rating of at least
105°C. Refer to the furnace nameplate and
Table 9 for electrical requirements.
Line Voltage Wiring
Thelinevoltage (115volt)tothe furnacemustbe
suppliedfromadedicatedbranchcircuitcontaining
thecorrect fuseor circuitbreaker forthe furnace.
(See Table 9.) An electrical disconnect must be
installedtobereadilyaccessiblefromandlocated
within sight of the furnace. (See the Wiring
Diagram label in the furnace and Figure 10.)
!
CAUTION:
Label all wires prior to disconnection
when servicing controls. Wiring errors
can cause improper and dangerous
operation.
Verify proper operation after servicing.
Thefurnacecabinetmusthaveanuninterrupted,
unbroken ground to minimize injury should an
electrical fault condition occur. The controls
used in this furnace require an earth ground
to operate properly. Acceptable methods for
groundingareelectricalwireorconduitapproved
for electrical ground service. Do not use gas
piping as an electrical ground.
IMPORTANT NOTE:
Proper line voltage polarity must be
maintainedinorderforthe control system to
operate correctly. Verify that the incoming
neutral line is connected to the white wire
and the incoming “hot” line is connected to
the black wire. These furnaces will not
operate unless the polarity and ground are
properly connected. See Figure 10.
Table 9. Electrical Data
** Time-delay fuses or HACR-type circuit breakers are required.
Thermostat Recommended Thermostat
Wire Wire Length
Gauge 2-wire 4 or 5-wire
(heating) (cooling)
24 55 ft. 25 ft.
22 90 ft. 45 ft.
20 140 ft. 70 ft.
18 225 ft. 110 ft.
Furnace Maximum Minimum Maximum
Model Number Furnace Wire Fuse or Circuit
*RA Amperes Gauge Breaker Amps**
045-08A 6.8 14 15
054-12A 9.3 14 15
072-12A 9.3 14 15
072-12B 9.3 14 15
072-16B 11.6 14 15
090-12B 9.3 14 15
090-16B 11.6 14 15
090-20B 15.6 12 20
108-16B 11.6 14 15
108-20B 15.6 12 20
108-20C 15.6 12 20
126-20C 15.6 12 20

17
R C Y G W
A/C Condensing Unit
Condensing Unit
Control Box
Room
Thermostat
Flame Signal Light
(Yellow)
Status Light
(Red)
60 90 120 180
Blower Off
Timing
TWIN
3 Amp
Fuse
COM
24 V
HUM
Neutrals
Low Voltage
Connections 41
52
63
7
8
9
4
5
6
1
2
3
EAC
HUM
M1 M2 M3
HEAT
L1
XFMR
Unused Motor Leads
EAC
R Y G W
Connect
R & W
For
Heating
Only
FIELD WIRING
NOTE:The "Y"
terminal on the
UTEC control board
must be connected
to the thermostat
for proper cooling
mode operation.
COOL
Figure 10. Line Voltage Field Wiring
Field Supplied Disconnect
Within Sight of Furnace
Field Supplied
Panel Connector
Field Supplied
Fused Service
Panel
Black (Hot)
White (Neutral)
Green or Bare
(Ground)
Black
White Black White Black White
Field Line Voltage
Wiring
Factory Line
Voltage Wiring
Ground Ground Ground
Junction Box (may be internal
or external to the furnace). These
connections can be made in the
field supplied disconnect at the
furnace.
Figure11. LineVoltageField,Four-wireHeating/CoolingApplications

18
Low Voltage Wiring
Install the thermostat per the manufacturer’s
instructions. The low voltage (24 volt)
connections from the thermostat are made at
theterminalstripontheintegratedcontrol inthe
furnace. See Figure 11 for the proper
connections for heating only (two-wire) and
heating/cooling (four-wire) applications. The
recommended minimum wire gauge for
thermostat wiring is shown in Table 9.
The thermostat must not be installed on an
outside wall or any other location where its
operation may be adversely affected. Adverse
affects include radiant loading from fireplaces,
sunlight,orlightingfixtures,andconvectiveloading
from warm air registers or electrical appliances.
To determine the heat anticipator setting either:
1. Add the current draw of the system
components; or
2. Measurethecurrentflowonthe thermostat
R-W circuit after the circulating blower
motor has started.
Set the heat anticipator according to the
thermostat manufacturer’s instructions for heat
anticipator settings.
START-UPANDADJUSTMENTS
General
Prior to start-up, verify that:
1. The line voltage power leads are securely
connected, that the polarity of the
connectionsiscorrect,andthatthefurnace
is properly grounded.
2. The thermostat wires (R, W, Y, and G) are
securely connected to the correct leads on
the terminal strip of the circuit board.
3. The gas line service pressure does not
exceed 10.0 in. water column (0.36 psig),
and is not less than 4.5 in. water column
(0.16 psig) for natural gas. For LP gas the
line service pressure must not exceed 14
in. water column (0.51 psig), and must not
be less than 11.0 in. w.c. (0.40 psig).
4. Theroll-outmanualresetswitchisclosed.
If necessary, press the red button to reset
a switch. DO NOT install a jumper wire
across a switch to defeat its function. If
a switch reopens on start-up, DO NOT
reset the switch without identifying and
correctingthefaultconditionwhichcaused
the switch to trip.
TIME FOR TIME FOR
ONE REVOLUTION ONE REVOLUTION
(SECONDS) 1 5 10 (SECONDS) 1 5 10
10 360 1800 3600 66 55 273 545
12 300 1500 3000 68 53 265 529
14 257 1286 2571 70 51 257 514
16 225 1125 2250 72 50 250 500
18 200 1000 2000 74 49 243 486
20 180 900 1800 76 47 237 474
22 164 818 1636 78 46 231 462
24 150 750 1500 80 45 225 450
26 138 692 1385 82 44 220 439
28 129 643 1286 84 43 214 429
30 120 600 1200 86 42 209 419
32 113 563 1125 88 41 205 409
34 106 529 1059 90 40 200 400
36 100 500 1000 92 39 196 391
38 95 474 947 94 38 191 383
40 90 450 900 96 38 188 375
42 86 429 857 98 37 184 367
44 82 409 818 100 36 180 360
46 78 391 783 102 35 176 353
48 75 375 750 104 35 173 346
50 72 360 720 106 34 170 340
52 69 346 692 108 33 167 333
54 67 333 667 110 33 164 327
56 64 321 643 112 32 161 321
58 62 310 621 114 32 158 316
60 60 300 600 116 31 155 310
62 58 290 581 118 31 153 305
64 56 281 563 120 30 150 300
GAS FLOW RATE (CUBIC FEET PER HOUR)
CUBIC FEETPER REVOLUTION OF
METER CUBIC FEETPER REVOLUTION OF
METER
Table 10. Gas Flow Rate

19
5. The blower door is in place, closing the
door switch in the line voltage circuit.
6. The gas line has been purged and all
connections are leak tight.
Start-up Procedures
After all of the above checks have been made:
1. Set the thermostat to the lowest setting.
2. Close the disconnect(s) to provide line
voltage to the furnace.
3. Follow the procedures given on the
operating instruction label attached to the
furnace.
4. Set the thermostat above room
temperature and verify the operating
sequence. (See the Sequence of
Operation).
5. Afterthefurnacehasrunforapproximately
five minutes, set the thermostat below
room temperature and verify steps (9)
through (11) of the Sequence of
Operation.
Verifying and Adjusting Firing Rate
The firing rate must be verified for each
installation to prevent over-firing the furnace.
Follow the procedure below to determine the
firing rate.
1. Shut off all other gas fired appliances.
2. Start the furnace and allow it to run for at
least three minutes.
Figure 12. Integrated Control
R C Y G W
(Yellow)
3 Amp Fuse
COM
24 V
HUM
Neutrals
41
52
63
7
8
9
4
5
6
1
2
3
EAC
HUM
M1 M2 M3
HEAT
COOL
L1
XFMR
Unused Motor
Leads
EAC
Electronic Air Tap
(.5A@ 120 VAC)
(Red)
Humidifier Tap
(.5A@ 120 VAC)
Connect Neutral
Lead of Electronic
Air Cleanerand/or
Humidifier Here.
Common
Leads
Twinning
Terminal
60
90
120
180
TWIN
Blower Off
Timing
Flame
Signal
Light
Status
Light
Cooling Speed Tap
Heatin
g
Speed Tap

20
IGNITOR
INDUCER
GAS
VALVE
SUPPLY AIR
LIMIT SWITCH
(ALL MODELS)
VENT
SAFETY SWITCH
(SELECT
MODELS ONLY)
TRANSFORMER
FLAME SENSOR
C
GREEN
BLACK
WHITE
BLUE BLUE
24 V 120 V
ORANGE
BLUE
BLUE
YELLOW
BROWN
RED
BLACK
WHITE
ORANGE
BLUE
BLACK
ORANGE
BLACK
RED
AIR CONDITIONER
CONDENSING UNIT
BLACK
BLACK
BLOWER DOOR
SWITCH
R
WHITE
BLACK
WHITE W/ BLK STRIPES
BLK W/ WHITE STRIPES
WHITE (NEUTRAL)
BLACK 120V
GROUND
ROOM THERMOSTAT
3 OR 4 SPEED MOTOR
H
MH
ML
L
C
WHITE
RED ORANGE
BLUE
BLACK
MOTOR
PLUG
1
2
3
4
5
6
BLACK
BLUE
FLAME ROLL-OUT
SWITCH
(ALL MODELS)
VENT
PRESSURE SWITCH
(93+ MODELS ONLY)
PRESSURE
SWITCH
R
Y
G
W
C
Y
180 120
90 60
These wires are
not present
on all models
BLOWER
DECK SWITCH
(SELECT
MODELS ONLY)
Legend
Field Wiring
Factory Wiring:
Low Voltage
High Voltage
Power On
Limit Circuit Open or External Load On "W"
Pressure Switch is Open with Inducer On
Pressure Switch is Closed with Inducer Off
Ignition Failure (Check Ground)
115 VAC & Neutral Reversed or no Ground
False Flame or Gas Valve Relay Shorted
ON
1 FLASH
2 FLASHES
3 FLASHES
4 FLASHES
5 FLASHES
Continuous
STATUS
RED
LIGHT
FAULT CONDITION
Power Off
Low Flame Sensor Signal
Flame Present
Continuous
Flash
OFF
ON
FLAME
YELLOW
LIGHT
FAULT CONDITION
BLUE
FLAME
ROLL-OUT SWITCH
(SELECT
MODELS ONLY)
Refer to the Installation
Instructions provided
with the furnace for the
proper heating and
cooling speeds for your
application.
VENT SAFETY SWITCH
(SELECT MODELS ONLY)
If any of the original
wire as supplied with
the furnace must be
replaced, it must be
replaced with wiring
material having a
temperature rating of
at least 105° C.
Use copper
conductors only.
WD#710355
Figure 13. Wiring Diagram