Nordyne G6RC 90+ User manual

Installation Instructions
These instructions are primarily intended to
assist qualified individuals experienced in
the proper installation of this appliance.
Some local codes require licensed installa-
tion/service personnel for this type of equip-
ment. Read all instructions carefully before
starting the installation.
DO NOT DESTROY. PLEASE READ CARE-
FULLY AND KEEP IN A SAFE PLACE FOR
FUTURE REFERENCE.
G6RC 90+, G6RD 93+ Upflow G6RL 90+ Downflow
G6RC Series 90+ Upflow Condensing Furnace
G6RD Series 93+ Upflow Condensing Furnace
G6RL Series 90+ Downflow Condensing Furnace
Residential Gas Furnaces
!WARNING:
Improper installation, adjustment, al-
teration, service, or maintenance can
cause injury or property damage. Re-
fer to this manual for assistance. For
additionalinformationconsultaquali-
fied installer, service agency, or the
gas supplier.
!FOR YOUR SAFETY:
Do not store or use gasoline or other
flammable vapors and liquids in the
vicinity of this or any other appliance.
!FOR YOUR SAFETY:
WHAT TO DO IF YOU SMELL GAS:
• Do not try to light any appliance.
• Donottouchanyelectricalswitch;do
not use any phone in your building.
• Immediately call your gas supplier
from a neighbor's phone. Follow the
gas supplier's instructions.
• Ifyoucannotreachyourgassupplier,
call the fire department.
• Extinguish any open flame.

Table of Contents
Furnace Specifications ............................................................................................................ 4-5
Furnace Airflow Data.......................................................................................................... 6-7
Installation Requirements .......................................................................................................... 8
Supply Air Plenum Installation ..................................................................................................9
Installation on a Concrete Slab ............................................................................................. 9
Installation on a Combustible Floor....................................................................................... 9
Circulating Air Supply............................................................................................................... 10
Return Air ............................................................................................................................ 11
Venting and Combustion Air Requirements .......................................................................... 11
Air Requirements for One-Pipe Installation ........................................................................ 13
Installation in An Unconfined Space ................................................................................... 13
Installation in A Confined Space ......................................................................................... 13
• Air From Inside .................................................................................................................. 13
• Air Directly Through An Exterior Wall ............................................................................... 14
• Outdoor Air Through Vertical Openings or Ducts ............................................................. 14
• Outdoor Air Through Horizontal Openings or Ducts......................................................... 14
Venting Requirements .............................................................................................................. 14
Vent Pipe Material ............................................................................................................... 14
Vent Pipe Length and Diameter .......................................................................................... 14
Vent Pipe Installation ..........................................................................................................15
Pipe Routing & Support....................................................................................................... 15
Location of Outdoor Terminations....................................................................................... 18
Horizontal Venting ............................................................................................................... 19
Vertical Venting ................................................................................................................... 20
Vent Freezing Protection..................................................................................................... 20
Concentric Vent Termination............................................................................................... 20
Drainage of Condensate From Furnace................................................................................. 21
Gas Supply and Piping........................................................................................................ 22
Leak Check.......................................................................................................................... 22
Conversion........................................................................................................................... 23
High Altitude Application ..................................................................................................... 23
Natural Gas High Altitude Conversion ................................................................................ 23
LP/Propane Gas Sea Level and High Altitude Conversion ................................................ 23
Electrical Wiring ........................................................................................................................ 24
Line Voltage Wiring .............................................................................................................24
Low Voltage Wiring ............................................................................................................. 25
Start-up and Adjustments......................................................................................................... 25
Start-Up Procedure..............................................................................................................26
Verifying and Adjusting Firing Rate..................................................................................... 26
Verifying and Adjusting Temperature Rise ......................................................................... 27
Verifying Burner Operation.................................................................................................. 27
Verifying Operation of the Supply Air Limit Switch ............................................................. 29
Description of Components ..................................................................................................... 29
Maintenance ............................................................................................................................... 31
Combustion Air and Vent System ....................................................................................... 31
Air Filter(s) ........................................................................................................................... 31
Lubrication ........................................................................................................................... 31
Condensate Drain Assembly............................................................................................... 31
Blower Compartment........................................................................................................... 31
Heat Exchanger and Burner Maintenance.......................................................................... 31
Location of Major Components ........................................................................................... 32
System Operation Information ................................................................................................. 31
Sequence of Operation ....................................................................................................... 33
Furnace Fails to Operate .................................................................................................... 34
Twinning of Two Furnaces .................................................................................................. 34
Installation/Performance Checklist ......................................................................................... 35

4
FURNACE SPECIFICATIONS
7/8" Dia. Electric
Connection
2 1/4"
23 1/4"
19 3/4"
3/4"
43"
25 1/8"
25 1/4"
23"
28"
15"
25 1/4"
33"
Return Air Opening
(Bottom)
Return Air Opening
(Side)
Bottom Return Opening
Condensate Drain Outlets
A
B
Combustion Air
Vent
(See Fig. 15
for sizes)
1 1/2" x 3 1/2" Dia.
Opening for
Gas Connection
+
3/4" 3/4"
3/4" 22 1/2"
Exhaust Vent
Combustion Air
Inlet
1 1/2" x 3 1/2" Dia.
Opening for
Gas Connection
C
2" PVC
Exhaust
Vent
(See Fig. 15
for sizes)
25 5/8"
20 1/2"
23"
+
7/8" Dia. Electric
Connection
30 1/4"
8"
8"
1 1/4"
1" D
27 5/8"
Upflow G6RC & G6RD Furnaces
Figure 1. G6RC, G6RD Unit Dimensions

5
3/4" 3/4"
2 1/2"
Combusting
Vent
(3" for 80/100
2" for 40/60)
L
C
A
C
D
B
Condensate
Drain
Outlet
Condensate
Drain
Outlet
7/8" Dia.
Electric
Connection
1 1/2" x 2 1/2"
Knockout
For Gas
Connection
Bottom Opening
27 7/8"
19 3/4"
7/8" Dia. Electric
Connection
24 1/2"
3/4"
43"
21 7/8"
21 1/2"
15 1/2" 21 1/2"
10 1/4"
Bottom Supply Air Opening
(Side)
Exhaust
Vent
2"
1 1/2" x 3 1/2" Dia.
Opening for
Gas Connection
3/4"
22 1/2"
Exhaust Vent
Combustion Air Inlet
24 7/8" 24 7/8"
21 7/8"
21 1/4"
8"
1"
Downflow G6RL Furnace
Figure 2. G6RL Unit Dimensions

6Table 1. Furnace Airflow Data
CAPACITIES —Furnace Airflow Data
External Static Pressure (Inches WaterColumn)
0.1 0.2 0.3 0.4 0.5 0.6 0.7 0.8
CFM Rise CFM Rise CFM Rise CFM Rise CFM Rise CFM Rise CFM Rise CFM Rise
950 36 920 38 890 39 850 41 800 43 750 46 690 50 630 55
740 47 710 49 680 51 650 53 600 58 550 63 490 - 430 -
620 56 590 59 560 62 520 - 470 - 410 - 350 - 290 -
1330 - 1280 - 1230 -
1170
- 1120 - 1030 - 940 37 850 41
1190 - 1160 - 1110 -
1060
- 1010 - 910 38 820 42 720 48
830 42 810 43 780 44 760 46 720 48 670 52 610 57 550 63
1310 - 1260 - 1210 -
1160
45 1100 47 1040 50 980 53 920 56
1160 45 1120 46 1080 48
1050
49 990 52 940 55 890 58 830 63
800 65 780 67 760 68 740 70 710 73 680 - 650 - 620 -
1490 46 1450 48 1390 50
1310
53 1210 57 1100 63 980 - 830 -
1230 56 1200 58 1150 60
1080
64 1010 69 910 - 810 - 680 -
780 - 750 - 720 - 680 - 630 - 570 - 510 - 440 -
1840 - 1780 - 1700 41
1630
42 1550 45 1470 47 1380 50 1290 54
1600 43 1560 44 1470 47
1400
49 1350 51 1280 54 1210 57 1150 60
1380 50 1350 51 1300 53
1250
55 1190 58 1120 62 1040 67 960 -
1100 - 1050 - 1000 - 950 - 900 - 850 - 800 - 750 -
1910 45 1860 47 1780 49
1700
51 1620 53 1520 57 1420 61 1310 66
1640 53 1620 53 1540 56
1480
58 1420 61 1340 65 1250 69 1150 75
1440 60 1410 61 1370 63
1320
66 1270 68 1210 72 1140 - 1060 -
1230 - 1210 - 1180 -
1140
- 1090 - 1030 - 960 - 880 -
1860 56 1800 58 1730 60
1650
63 1570 66 1480 70 1380 75 1270 82
1650 63 1610 65 1550 67
1480
70 1410 74 1320 79 1230 84 1120 -
1440 72 1410 74 1380 75
1320
79 1280 81 1220 85 1150 - 1080 -
1230 - 1210 - 1180 -
1140
- 1090 - 1030 - 960 - 880 -
2260 - 2200 - 2140 -
2070
- 1990 - 1910 - 1810 57 1710 61
1870 56 1840 56 1790 58
1760
59 1710 61 1660 63 1610 65 1560 67
1540 67 1530 68 1510 69
1470
71 1430 73 1370 76 1300 80 1220 85
1360 - 1330 - 1310 -
1280
- 1250 - 1220 - 1190 - 1150 -
1050 - 1005 - 960 - 915 - 855 - 800 - 730 48 670 53
990 - 950 - 905 - 860 - 810 - 760 46 700 50 650 54
770 46 740 48 700 50 660 53 625 56 580 61 540 65 500 70
1175 45 1125 47 1075 49
1030
51 970 54 920 57 860 61 800 66
1075 49 1040 51 995 53 950 56 900 59 840 63 790 67 720 73
800 66 770 69 745 71 710 74 670 - 630 - 580 - 530 -
Heating
Model Input Motor Motor
Number (Btuh) Speed HP
Hi
g
h*
G6RC040C-08
40,000 Medium 1/5
Low**
Hi
g
h*
G6RC040C-12
40,000 Medium 1/3
Low**
Hi
g
h*
G6RC060C-12
60,000 Medium 1/3
Low**
Hi
g
h*
G6RC080C-12
80,000 Medium 1/3
Low**
Hi
g
h*
G6RC080C-16
80,000
Med-High
1/2
Med-Low**
Low
Hi
g
h*
G6RC100C-16
100,000 Med-Hi
g
h** 1/2
Med-Low
Low
Hi
g
h*
G6RC120C-16
120,000 Med-Hi
g
h** 1/2
Med-Low
Low
Hi
g
h*
G6RC120C-20
120,000
Med-High
3/4
Med-Low**
Low
Hi
g
h*
G6RD040C-10
40,000 Medium 1/3
Low**
Hi
g
h*
G6RD060C-10
60,000 Medium** 1/3
Low

7
Table 2. Furnace Airflow Data
Heating
Model Input Motor Motor
Number (Btuh) Speed HP
Hi
g
h*
G6RD080C-14 80,000
Med-High
1/2
Med-Low**
Low
Hi
g
h*
G6RD100C-14 100,000 Med-Hi
g
h** 1/2
Med-Low
Low
Hi
g
h*
G6RD120C-14 120,000 Med-Hi
g
h** 1/2
Med-Low
Low
Hi
g
h*
G6RD120C-19 120,000
Med-High
3/4
Med-Low**
Low
External Static Pressure (Inches WaterColumn)
0.1 0.2 0.3 0.4 0.5 0.6 0.7 0.8
CFM Rise CFM Rise CFM Rise CFM Rise CFM Rise CFM Rise CFM Rise CFM Rise
1620 - 1560 45 1490 47
1430
49 1365 52 1300 54 1240 57 1170 60
1450 49 1400 50 1350 52
1295
54 1240 57 1180 60 1120 63 1060 66
1255 56 1225 57 1180 60
1145
61 1105 64 1060 66 1020 69 980 72
1080 65 1055 67 1030 68
1000
70 960 73 920 - 870 - 820 -
1620 54 1555 57 1485 59
1425
62 1355 65 1290 68 1220 72 1160 -
1430 62 1375 64 1330 66
1265
70 1210 73 1150 - 1080 - 1010 -
1260 70 1220 72 1170 75
1130
- 1070 - 1010 - 950 - 890 -
1085 - 1050 - 1015 - 970 - 935 - 890 - 850 - 800 -
1700 62 1635 65 1565 67
1500
70 1435 74 1370 77 1310 - 1240 -
1510 70 1455 73 1405 75
1350
78 1290 - 1230 - 1170 - 1100 -
1330 79 1280 - 1240 -
1195
- 1145 - 1100 - 1050 - 1000 -
1140 - 1110 - 1075 -
1040
- 1010 - 980 - 940 - 910 -
2140 - 2070 - 2010 -
1945
- 1870 56 1800 59 1730 61 1650 64
1955 - 1900 56 1850 57
1800
59 1740 61 1690 62 1630 65 1570 67
1660 64 1620 65 1575 67
1540
69 1495 71 1460 72 1410 75 1370 77
1450 73 1430 74 1400 75
1360
78 1340 79 1300 81 1270 83 1230 -
1280 - 1210 - 1180 - 1140 - 1090 - 1070 - 1030 - 990 -
1140 - 1090 - 1060 - 1030 - 980 35 950 36 910 37 870 39
875 39 835 41 820 41 805 42 780 43 770 44 760 45 750 45
1260 40 1190 43 1155 44 1120 45 1075 47 1030 49 980 52 940 54
1120 45 1070 48 1040 49 1010 50 960 53 930 55 890 57 850 60
855 59 815 62 800 64 780 65 760 67 730 70 710 - 690 -
1635 - 1585 - 1525 - 1460 46 1400 48 1330 51 1260 54 1180 57
1435 47 1395 49 1350 50 1300 52 1255 54 1200 56 1150 59 1090 62
1230 55 1200 56 1165 58 1130 60 1090 62 1050 65 1000 68 960 71
1050 - 1035 - 1010 - 980 - 950 - 910 - 870 - 820 -
1600 53 1555 54 1500 56 1445 59 1380 61 1310 65 1240 68 1160 73
1475 57 1435 59 1385 61 1335 63 1290 66 1240 68 1190 71 1130 75
1320 - 1290 - 1250 - 1215 - 1170 - 1120 - 1070 - 1020 -
1150 - 1130 - 1110 - 1075 - 1040 - 1000 - 950 - 890 -
High*
G6RL040C-12 40,000 Medium 1/3
Low**
High*
G6RL060C-12 60,000 Medium 1/3
Low**
High*
G6RL080C-16 80,000 Med-High 1/2
Med-Low**
Low
High*
G6RL100C-16 100,000 Med-High** 1/2
Med-Low
Low
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 and airflows for external static pressures greater than 0.5 are for reference only.
These conditions are not recommended.
** Factory Set Cooling Speed
** Factory Set Heating Speed
- Not Recommended

8
Table 3. Furnace Dimensions and Shipping Weights
Table 4. Minimum Clearances to Combustible Materials
* 24 inches is the minimum clearance for servicing.
36 inches is the recommended clearance for service.
CLEARANCES TO COMBUSTIBLE MATERIALS
This furnace is Designed Certified by AGA/CGA Laboratories for the minimum clearances to
combustible material listed in Table 4. See the furnace name plate, located inside the furnace
cabinet, for specific model number and clearance information.
MINIMUM CLEARANCES TO COMBUSTIBLE MATERIAL
Furnace Cabinet Minimum Clearances (Inches)
Input Width
(Btuh) (Inches) Side Vent Back Top Front
40,000 14 1/4 0 0 0 1 1*
60,000 14 1/4 0 0 0 1 1*
80,000 14 1/4 0 0 0 1 1*
100,000 19 3/4 0 0 0 1 1*
120,000 22 1/2 0 0 0 1 1*
INSTALLATION REQUIREMENTS
Requirements and Codes
This furnace must be installed in accordance
withtheseinstructions,allapplicablelocalbuild-
ing codes, and the current revision of the Na-
tionalFuelGasCode(ANSI-Z223.1,NFPA-54).
The current revision of the National Fuel Gas
Code is available from:
American National Standards Institute, Inc.
1430 Broadway
New York, New York 10018
Canada installations shall comply with CAN/
CGA-B149installation codes,local plumbing or
waste water codes and other applicable codes.
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 in-
stallation in mobile homes. Installa-
tion in a mobile home could cause
fire,propertydamage,and/orpersonal
injury.
G6R(C,D)040C 40,000 14 1/4 12 3/4 5 1/8 11 3/4 133
G6R(C,D)060C 60,000 14 1/4 12 3/4 5 1/8 11 3/4 140
G6R(C,D)080C 80,000 19 3/4 18 1/4 7 7/8 17 1/4 172
G6R(C,D)100C 100,000 19 3/4 18 1/4 7 7/8 17 1/4 180
G6R(C,D)120C 120,000 22 1/2 21 9 1/4 20 204
G6RL040C 40,000 14 1/4 12 3/4 4 5/8 12 3/4 135
G6RL060C 60,000 14 1/4 12 3/4 4 5/8 12 3/4 135
G6RL080C 80,000 19 3/4 18 1/4 10 18 1/4 174
G6RL100C 100,000 19 3/4 18 1/4 10 18 1/4 185
AB
Dimensions (inches)
Furnace
Btuh CD
Shipping
Weight
(
lbs
)
Model
Number

9
Location
Thefurnacemustbeinstalledonalevelsurface,
and as close to the center of the air distribution
system as possible. See Table 3 for overall
dimensions to determine the required clear-
ancesinhallways,doorways,stairs,etc.toallow
thefurnaceto bemovedtothe installationpoint.
The furnace must be installed so that all electri-
cal components are protected from water.
Minimum clearances to combustible materials
are listed in Table 4. Access for positioning and
servicing must be considered when locating the
unit. 24 inches is the minimum required clear-
ance for servicing the unit. 30 inches is the
minimum required clearance for positioning the
unit. 36 inches is the recommended clearance
from the front of the unit. Please note that a
panel or door can be located such that the
minimum clearance on the rating plate is satis-
fied, but that panel or door must be removable
and allow the appropriate clearance for your
installation.
Thisfurnaceiscertifiedforuseonwoodflooring.
Thefurnace mustbe installedona solidsurface
and must be level front to back and side to side.
This furnace must not be installed directly on
carpeting,tile,oranycombustiblematerialother
than wood flooring.
DOWNFLOW WARNING
(G6RL Models):
The design of the downflow furnace is certified
fornaturalor propanegasandfor installationon
non-combustible flooring. A special combus-
tible floor sub-base is required when installing
onacombustiblefloor. Failuretoinstallthesub-
base may result in fire, property damage and
personalinjury.Thespecialdownflowsub-bases
are factory supplied accessories, part numbers
902677 and 902974. When the furnace is in-
stalled on a factory or site-built cased air condi-
tioning coil, the sub-base is not necessary.
However,theplenumattachedtothecoilcasing
must be installed such that its surfaces are at
least 1" from combustible construction.
A gas-fired furnace installed in a residential
garage must be installed so that the bottom of
thefurnaceislocatedaminimumof15"fromthe
floor. The furnace must be located or protected
to avoid physical damage by vehicles.
HORIZONTAL INSTALLATIONS
The G6RC model furnaces are approved for
horizontal installation. Installation Kit #903568
is required for horizontal applications. Follow
the installation instructions in the kit for proper
conversion. NOTE: The G6RD and G6RL mod-
elsareNOTapprovedforhorizontalinstallation.
SUPPLY AIR PLENUM INSTALLATION
A. Installation on a concrete slab - G6RL
1. Construct a hole in the floor per the
dimensions in Figure 3.
2. Place the plenum and the furnace as
shown in Figure 4.
B. Installationonacombustiblefloor-G6RL
1. Cut and frame the hole in the floor per
the dimensions in Figure 5.
2. Place the sub-base for combustible floors
over the hole with its duct collar extended
downward.Attachthesupplyairplenumto
the base in a manner which will ensure 1"
clearancetotheflooringorothercombustible
material.Placefurnaceonthecombustible
base as shown in Figure 6.
3. Whenthefurnaceisinstalledonafactory
or site-built cased air conditioning coil,
thesub-baseisnotnecessary.However,
the plenum attached to the coil casing
must be installed such that its surfaces
areatleast1"fromcombustiblematerial.
Hole in
Floor
19.25"
18.75"
Hole in
Floor
19.25"
13.25"
G6RL 080/100 G6RL 040/060
Figure 3. Opening for Concrete Slab

10
19.63"
18.75"
19.63"
13.25"
Hole in
Floor Hole in Floor
Downflow Wood
Sub-base Floor
Furnace
Sheet
Metal
Plenum
Figure 5. Opening in Wood Floor
G6RL 080/100 G6RL 040/060
Figure 6. Furnace on a Wood Floor
1 inch thick fiberglass 3 lb density
28.38"
9.25"
19.63"
3"
19.75"
or 14.25"*
2.0"
1.58"
1.50"
16.75"
or 11.25"*
18.75"
or 13.25"*
Concrete
Floor Furnace
Sheet
Metal
Plenum
Figure 4. Furnace on a Concrete Slab
CIRCULATING AIR SUPPLY
Plenums and air ducts must be installed in
accordance with the Standard for the Installa-
tionof AirConditioning andVentilating Systems
(NFPANo.90A) ortheStandard fortheInstalla-
tion of Warm Air Heating and Air Conditioning
Systems (NFPA No. 90B).
* Smaller
dimensions for
G6RL 040/060
Figure 7. Downflow Sub-Base Dimensions
Ifoutside airisutilized asreturn airtothe furnace
forventilation or toimprove indoor airquality, the
systemmust be designedso thatthe return airto
the furnace is not less than 50°F (10°C) during
heating operation. If a combination of indoor and
outdoorairisused,theductsanddampersystem
must be designed so that the return air supply to
thefurnaceis equaltothereturn airsupplyunder
normal, indoor return air applications.
When a cooling system is installed which uses
the furnace blower to provide airflow over the
indoor coil, the coil must be installed down-
stream (on the outlet side) or in parallel with the
furnace.
Ifacoolingsystemisinstalledinparallelwiththe
furnace, a damper must be installed to prevent
chilled air from entering the furnace and con-
densing on the heat exchanger. If a manually
operated damper is installed, it must be de-
signed so that operation of the furnace is pre-
vented when the damper is in the cooling posi-
tion and operation of the cooling system is
prevented when the damper is in the heating
position.

11
!WARNING:
Products of combustion must not be
allowedtoenterthereturnairductwork
orthecirculatingairsupply. Failureto
prevent products of combustion from
being circulated into the living space
cancreatepotentially hazardouscon-
ditions including carbon monoxide
poisoning that could result in per-
sonal injury or death.
All return ductwork must be ad-
equately sealed, all joints must be
taped, and the ductwork must be
securedtothefurnacewithsheetmetal
screws. When return air is provided
throughthebottomofthefurnace,the
joint between the furnace and the re-
turn air plenum must be sealed.
The floor or platform on which the
furnace is mounted must provide
soundphysicalsupportofthefurnace
with no gaps, cracks, or sagging be-
tween the furnace and the floor or
platform.
Returnairandcirculatingairductwork
must not be connected to any other
heat producing device such as a fire-
place insert, stove, etc.
Return Air
The return air ductwork may be connected to
any or all of the following: left side return, right
side return, or bottom return. Tables 1 and 2
show the airflow data for each furnace model.
Where maximum airflow is 1800 CFM or
more two openings must be used.
VENTING AND COMBUSTION AIR
REQUIREMENTS
NORDYNE condensing furnaces may be in-
stalled with outdoor combustion air piped di-
rectly to the furnace, or without such special
piping. Codesrefertotheformeras"directvent"
or "two pipe" installation. Installation with air
taken from around the furnace is sometimes
referred to as "one pipe" installation - i.e. only
the vent (exhaust) pipe is provided. Figure 8. Protective Screen for One Pipe
Installations
ProtectiveScreen
G6RC/G6RD
G6RL
An important consideration in selecting one or
twopipeinstallationisthequalityofthecombus-
tion air. Indoor air is sometimes contaminated
with various household chemicals which can
cause severe corrosion in the furnace combus-
tion system. Some common sources of these
chemicals are detergents, bleaches, aerosol
sprays,andcleaningsolvents.Unlessindoorair
is known to be free of these materials, two pipe
installation is recommended.
Provisionsmustbemadeforadequatesupplyof
air for combustion and ventilation. For United
States installations, the adequacy of air provi-
sions can be determined by consulting the cur-
rent version of the National Fuel Gas Code
(ANSIZ223.1/NPFA-54).ForCanadianinstalla-
tions,requirementsare specifiedintheNational
Standard of Canada (CAN/CGA B149.1 & .2).
Consult local codes for special requirements.
NOTE: If the furnace is operated without ad-
equateairforcombustion andventilation,itmay
notperformproperly.Furnacecomponentsmay
be strained by high temperature and could fail
prematurely.
!WARNING:
Furnace installation using methods
other than those described in the fol-
lowingsections mustcomply withthe
National Fuel Gas Code and all appli-
cablelocalcodestoprovidesufficient
combustion air for the furnace.

12
Each opening
to outside must
be at least
1 sq. in. per
4000 Btuh of
total input
rating.
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
12"
Max
Figure 11. Equipment in a Confined Space
with all Combustion Air drawn from
Outdoors through Vertical Ducts – from
Ventilated Attic
Air Duct must be
at least 1 sq. in.
per 4,000 Btuh of
total input rating.
Ducts must
extend above
attic insulation.
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
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
Figure 10. Equipment in a Confined Space
with all Combustion Air drawn from
Outdoors through Exterior Wall
,,,,,
,,,,,
Water
Heater
Vent or
Chimney
- - - - - - - - -
- - - - - - - - -
Furnace
Ventilation Louvers For
Unheated Crawl Space
- - - - - - - - -
Inlet Air
Ventilation Louvers
(each end of attic)
NOTE: Air open-
ings shall each
have a free area
of not less than
one square inch
per 4,000 Btuh of
the total input rat-
ing of all equipment
in the enclosure.
- - - - - - - - -
Alternate
Air Inlet
Outlet
Air
Total Input
Rating (Btuh)
40,000
60,000
80,000
Round Duct
Diameter
12"
12"
12"
Minimum
Free Area
(Each Opening)
100 sq. in.
100 sq. in.
1
00
sq
. in.
Furnace
12" Max.
12" Max.
Water Heater
Vent or
Chimney 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.
Figure 9. Equipment in a Confined Space
with all Combustion Air drawn from Inside
Figure 12. Equipment in a Confined Space
with all Combustion Air drawn from
Outdoors through Ventilated Crawl Space
and Ventilated Attic

13
Total Input
Rating (Btuh)
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
Water Heater
Air Duct
must be
at least
1 sq. in.
per 2000
Btuh of
total input
rating.
Vent or
Chimney
Air Duct
Air Duct
Figure 13. Equipment in a Confined Space
with all Combustion Air Drawn from the
Outside through Horizontal Ducts
Air Requirements For One-Pipe
Installation
When air for combustion is to be taken from
aroundthefurnace, aprotectivescreenmustbe
installed over the combustion air intake open-
ing. This screen is provided with the furnace
installationinstructions andfunctions toprevent
debris from entering the combustion system. It
should be installed on the combustion air intake
collar or inlet PVC. If furnace location is such
that this opening might be unintentionally ob-
structed, a 3" PVC elbow should be installed on
the collar, and the screen placed inside the inlet
of the elbow. See Figure 8.
Installation In An Unconfined Space
!CAUTION:
"Tight" buildings (with weather strip-
ping and caulk to reduce infiltration),
may require special provisions for in-
troduction of outside air to ensure
satisfactory combustion and venting,
even though the furnace is located 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
combustion air from that space. For example, a
space including a water heater rated at 45,000
Btuhanda furnaceratedat 75,000Btuhrequires
a volume of 6,000 cubic feet [50 x (45 + 75) =
6,000]to beconsidered unconfined. Ifthe space
has an 8 foot ceiling, the floor area of the space
must be 750 square feet (6,000 / 8 = 750). In
general, a furnace installed in an unconfined
space will not require outside air for combustion.
!WARNING:
Furnaces installed with combustion
air drawn from a heated space which
includes exhaust fans, fireplaces, or
other devices that may produce a
negative pressure should be consid-
ered confined space installations.
Installation In A Confined Space
Aconfinedspaceisonewhichdoesnotmeetthe
unconfined space volume requirements, and
typicallyinvolvesinstallation inasmallroom. All
such installations must have specific provisions
for introduction of combustion and ventilation
air. Codes require that two openings be pro-
vided for this - one with bottom edge within 12"
of the floor and one with top edge within 12" of
the ceiling.
The size and other criteria for these
openings must be per the following sections.
Combustion air openings must not be restricted
in any manner.
Furnaces installed in a confined space which
supply circulating air to areas outside of the
space must draw return air from outside the
space and must have return air ducts tightly
sealed to the furnace.
Air From Inside
Air for combustion and ventilation may be taken
from inside the building through an interior wall
ifthebuildingisnot"tight" andifthetotalvolume
of the furnace space and the space from which
air is drawn meets the volume requirements for
an unconfined space.
In such cases, the two
openingsinthewallmusteachhavefreeareaof
at least one square inch per 1000 Btuh of
total
appliance input, but not less than 100 square

14
inches of free area. See Figure 9. For example,
ifthecombinedinputrateofallappliancesisless
than or equal to 100,000 Btuh,
each opening
must have a free area of at least 100 square
inches. If the combined input rate of all appli-
ancesis120,000Btuh,
each openingmusthave
a free area of at least 120 square inches.
Air Directly Through An Exterior Wall
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. (See Figure 10.)
OutdoorAirThroughVerticalOpeningsorDucts
If combustion air is provided through vertical
ducts or openings to attics or crawl spaces, the
two openings must each have free area of at
least one square inch per 4000 Btuh of total
appliance input. Ducts must have cross-sec-
tional areas at least as large as the free area of
their respective openings to the furnace space.
Atticsor crawl spacesmust communicatefreely
with the outdoors if they are the source of air for
combustion and ventilation. (See Figures 11
and 12.)
Outdoor Air Through Horizontal
Openings or Ducts
Ifcombustion airis takenfromoutdoors through
horizontal ducts, the openings must
each have
free area of at least one square inch per 2000
Btuh of total appliance input. Ducts must have
cross-sectionalareaat leastaslarge asthefree
area of their respective openings to the furnace
space. (See Figure 13.)
!CAUTION:
Donotsupply combustionairfrom an
atticspacethatisequippedwithpower
ventilation or any other device that
may produce a negative pressure.
VENTING REQUIREMENTS
This section specifies installation requirements
for vent and "2-pipe" combustion air piping. For
"one pipe" installations, install vent piping per
this section and provide air for combustion and
ventilation per the previous section. The capac-
ity table provided in this section applies to the
total of vent and combustion air piping for either
type of installation.
NORDYNE condensing furnaces are classified
as"CategoryIV" appliances,whichrequire spe-
cial venting materials and installation proce-
dures. Category IV appliances operate with
positive vent pressure and therefore require
ventsystemswhicharethoroughlysealed. They
also produce combustion condensate, which is
slightlyacidicandcancauseseverecorrosionof
ordinary venting materials. Furnace operation
canbeadverselyaffectedbyrestrictiveventand
combustionairpiping.Therefore,
ventandcom-
bustion air piping lengths must conform com-
pletely to the requirements of Table 5.
The furnace must be vented to the outdoors. It
must not be vented in common with any other
appliance, even if that appliance is of the con-
densing type. Common venting can result in
severe corrosion of other appliances or their
venting and can allow combustion gases to
escape through such appliances or vents. Do
not vent the furnace to a fireplace chimney or
building chase.
!WARNING:
FURNACE MUST NOT BE COMMON
VENTED WITH OTHER APPLIANCES.
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
Cement and primer must conform to ATSM
Standard D2564 for PVC and Standard D2235
for ABS. When joining PVC piping to ABS, use
PVC solvent cement. (See procedure specified
in ASTM Standard D3138.)
Vent Pipe Length and Diameter
In order for the furnace to operate properly, the
combustionairandventpipingmustnotbeexces-
sivelyrestrictive. ToensurethisuseTable5,which
indicatesthemaximumallowablepipinglengthfor
a furnace of specified input rate, when installed

15
with piping of selected diameter and number of
elbows. This table applies to the length and num-
ber of elbows for each pipe. To use the table, the
furnace input rate, the centerline length and the
number of elbows on each pipe must be known.
Choosethediameterforwhichthetabulatedlength
is equal to or greater than required.
Proper use of the table is illustrated by the
following example:
Example:
An 80,000 Btuh furnace is to be installed in a
"one-pipe" system with 40 feet of vent piping.
There are four elbows, including those exterior
to the building.
Solution:
Consulting Table 5, in the single pipe length
column for an 80,000 Btuh furnace, the maxi-
mum allowable length of 2" is 60 feet with one
elbow. Select 2-1/2 or 3" pipe. For three addi-
tional elbows, deduct 2.5 ft. for each elbow, or
7.5 ft. for a maximum installed vent length of
52.5 ft.
Condensing furnace combustion products have
very little buoyancy, so Table 5 is to be used
without consideration of any vertical rise in the
piping.
NOTE: Always use the same or larger size
piping for combustion air as is used for the
exhaust vent.
Vent Pipe Installation
Pipe Routing and Support
Routepipingasdirectlyaspossiblebetweenthe
furnace and the outdoors and remember that
routing affects pipe size requirements per the
preceding section. If a two pipe system is used,
locate the combustion air intake and the vent
exhaustinthesameatmosphericpressurezone
-i.e.bothmustexitthebuildingthoughthesame
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.
Thisistoensurethatanycondensateflowsback
to the furnace (where it can be disposed of
through the condensate disposal system).
The quality of outdoor air must also be consid-
ered. 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.
!
CAUTION:
Combustion air must not be drawn
from a corrosive atmosphere.
*NOTES
1. Subtract 2.5 ft. for each additional 2" elbow and 3.5 ft. for each additional 3" elbow.
2. Two 45 degree elbows are equivalent to one 90 degree elbow.
3. One short radius elbow is equivalent to two long radius elbows
4. Do not include termination elbows in calculation of vent length
5. This table is applicable for elevations from sea level to 2000 ft. For higher elevations decrease
vent pipe lengths by 8% per 1000 ft. of altitude.
6. Only the above pipe materials are approved for use with G6 Condensing Furnaces.
Table 5. Vent Table
APPLICATION SINGLE PIPE LENGTH (ft.) DIRECT VENT,DUAL PIPE LENGTH (ft.)
with 1 long radius elbows*. with 1 long radius elbows on each pipe.*
PVC,CPVC or ABS Outlet Outlet Inlet/Outlet Inlet/Outlet Inlet/Outlet
SCH. 40 Pipe Size 2" 3" 2" 2" 3" 2" 3" 3"
Models
G6RC,D,L 80 150 40 40 50 50 90 90
040
Models
G6RC,D,L 60 150 30 30 35 35 90 90
060 & 080
Models
G6RC,D,L 30 150 15 15 25 25 90 90
100 & 120

16
G6RL Downflow Furnaces
G6RC & G6RD Upflow Furnaces
5/8" Inlet Exhaust
Combustion
Offset with
Exhaust Pipe
for Adequate
Dimensional
Clearance
PVC or
ABS Pipe
SeeVentTable 4
Straps or Other Suitable
Supports at Minimum of 5 ft. Intervals
Upward Pitch - 1/4" per Foot
Outlet ExhaustVent
First Support Placed
as Close to Furnace
Connection as Possible
ExhaustVent
Wall
Coupling
Seal/Caulk
around Pipe
at Building
90˚ Elbow
12" Min.
Normal Snow Level
7"
Straight Neoprene Coupling
with 2 Hose Clamps*
(Optional - Not Shown)
5/8"
Inlet
Exhaust
Combustion Air
Inlet
Offset with Exhaust
Pipe for Adequate
Dimensional
Clearance
PVC or
ABS Pipe
SeeVentTable 4
Straps or Other Suitable
Supports at Minimum of 5 ft. Intervals
Upward Pitch - 1/4" per Foot
Outlet ExhaustVent
First Support Placed
as Close to Furnace
Connection as Possible
ExhaustVent
Wall
Coupling
Seal/Caulk
around Pipe
at Building
90˚ Elbow
12" Min.
Normal Snow Level Straight Neoprene
Coupling with
2 Hose Clamps
Figure 14. Horizontal Venting
* These couplings are field-supplied and can be used if the installation requires breakable
connections in the piping. Note that a maximum of two couplings per pipe are allowed.

17
Combustion
Air Pipe
Exhaust
Vent
Cabinet
5'
Support System on
Vertical Rise Below Joints
Support System with
first support as close
to furnace as Possible
Upward Pitch
1/4" per Foot
Furnace Front
Straight Neoprene
Rubber Couplings
with 2 Hose Clamps
Combustion
Air Pipe Exhaust Vent
Cabinet
5'
Support System on
Vertical Rise Below Joints
Support System with
first support as close
to furnace as Possible
Upward Pitch
1/4" per Foot
Furnace Front
Straight Neoprene
Couplings with
2 Hose Clamps*
(Optional - Not
Shown)
Combustion Air Inlet
2" PVC on G6RL 040/060 models,
3" PVC on G6RL 080/100 models
2" PVC
ExhaustVent
All Models
FurnaceTop
Combustion Air Inlet Pipe Collar
Diameter 3" for coupling or reducer
FurnaceTop
2" PVC
ExhaustVent
All Models
G6RL Downflow Furnaces
G6RC & G6RD Upflow
Furnaces
G6RL Downflow Furnaces
G6RC & G6RD Upflow
Furnaces
Figure 16. Furnace Pipe Adaptions
Figure 15. Vertical Venting
* These couplings are field-supplied and can be used if the installation requires breakable
connections in the piping. Note that a maximum of two couplings per pipe are allowed.

18
4 ft. min
12 in. min
12 in. min
12 in. min
9 in.
4 ft. min
12 in. min
12 in. min
Mechanical
draft vent
terminal
Direct vent
terminal
50,000 Btuh
or less
Forced
Air Inlet
Direct vent
terminal -
more than
50,000 Btuh
Mechanical
draft vent
terminal
Mechanical
draft vent
terminal
Grade
Less
than 10 ft.
3 ft. min.
Piping must be mechanically supported so that
its weight does not bear on the furnace. Sup-
ports must be at intervals no greater than five
feet, and at smaller intervals if necessary to
ensurethattherearenosaggingsectionstotrap
water. (See Figures 14 and 15.)
Figure 16 illustrates vent and combustion air
pipe sizes exiting the furnace. Transition to the
correct pipe size must be done close to the
furnaceso thatthe fulllengthof pipeis ofproper
size.
Straight neoprene couplings are supplied with
the downflow furnaces only. These couplings
are to be installed in the combustion air inlet (if
present) and exhaust vent piping at the furnace
as shown in Figures 13 and 14. For an upflow
furnace installation, if breakable connections
arerequiredinthecombustionairinlet(ifpresent)
andexhaustvent piping,thenstraightneoprene
couplings for 2” or 3” piping with hose clamps
can be used. These couplings can be ordered
through your local furnace distributor.
To install a coupling, slide the rubber coupling
over the end of the pipe that is attached to the
furnace and secure it with one of the hose
clamps. Then slide the other end of the rubber
coupling onto the other pipe from the vent and
securethecouplingwiththesecondhoseclamp.
Ensurethattheconnectionistightandleakfree.
NORDYNE condensing furnaces have been
certified for installation with zero clearance be-
Figure 17. Vent Termination Clearances
tween vent piping and combustible surfaces.
However, it is good practice to allow space for
convenience in installation and service.
Location of Outdoor Terminations
Vent and combustion air intake terminations
mustbelocatedtoensureproperfurnaceopera-
tion and to conform to applicable codes. Figure
16 illustratesnecessarydistancesfromthevent
termination to windows and building air intakes.
In Canada, the Canadian Fuel Gas Code
takes precedence over these instructions.
Specifically, all minimum distance require-
mentswithrespect toterminationofthe vent
piping listed below (items 1 through 8).
The following list is a summary of vent terminal
location requirements:
1. The termination must be 12 inches above
snowlevelorgradelevelwhicheverishigher.
See Figure 18 for alternate method to
achieve 12" above snow level.
2. The minimum distance for a (1-pipe instal-
lation) from any door, (openable) window,
orgravityairinletis4ft.below,4ft.horizon-
tally, or 1 ft. above.
3. The minimum distance for a direct vent (2-
pipe)installation)fromanydoor,(openable)
window,orairgravityinletis1ft.below,1ft.
horizontally, or 1 ft. above.
4. Forone-pipeinstallationstherecommended
minimum distance from an inside corner
formed by two exterior walls is 6 feet, but is
not required.

19
5. The vent termination for a 1-pipe installa-
tion shall be a minimum of 3 ft. above any
forced air inlet within 10 ft.
6. The vent termination shall be located at
least 4 ft. horizontally from any electric
meter, gas meter, regulator and any relief
equipment.ThesedistancesapplyONLYto
U.S.installations.InCanada,theCanadian
Fuel Gas Code takes precedence.
7. Avoid areas where condensate drainage
may cause problems by dropping on plant-
ersor patios, etc. Alsoensure thatexhaust
gaseswill notimpingeon windowsor build-
ing surfaces, which may be compromised
ordamagedbycondensation. Donotinstall
the vent terminal such that exhaust is di-
rected into window wells, stairwells, under
decks or into alcoves or similar recessed
areas, and do not terminate above any
public walkways.
8. Select the point of wall penetration where
the minimum 1/4 inch per foot of slope up
can be maintained.
!CAUTION:
For optimum performance, vent fur-
nace through wall which experiences
the least exposure to winter winds.
Horizontal Venting
Vent and combustion air intake terminations
must be as shown in Figure 19.
!WARNING:
Ensure that the combustion air vent
andtheexhaustventareconfiguredas
shown in Figure 19. Improper vent
termination can cause recirculation of
the flue gases. This may result in fur-
nace vibration. In severe cases, the
furnace will cycle due to the intermit-
tentcontactbetweentheflameand the
flame sensor. If you note oscillations
occurring, check the vent configura-
tion. Make sure that the exhaust vent
doesnothavea90degreetermination.
Figure 18. Alternate Horizontal Vent
Installation
,Q¢
Outside
Wall Support
Pipe
Coupling
Vent Configuration to
Provide 12" Minimum
height above
Snow Level.
1/2"
Armaflex
Insulation or
Equivalent
12" Above
Normally
Expected
Snow
Level
12" Min.
19" Max.
For horizontal venting, one of the following kits
is recommended:
2" PVC 3" PVC
Through-the-Wall
Exterior Vent
Mountin
g
Kit 9023730 9023750
Neutralizer Kit - All
Models 9023730 9023730
For Canadian installations please refer to the
Canadian Installation Code (CAN/CGA-B149.1
or 2) and/or local codes.
The kit consists of two face plates and an
insulating gasket to seal the exterior surface. A
holesizedclosely tothepipediameter mustfirst
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
sidesofthewallbythecouplings,andthegasket
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 appro-
priate 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 exterior
wall.Insurethattheholediameterislessthan
the diameter of the couplings to be used.
2. Extend the vent pipe through the wall ap-
proximately 1" and seal the area between
the wall and pipe.

20
3. Apply couplings to the vent pipe on the
interior and exterior sides of the wall to
insure the pipe can not be pushed or pulled
through the wall.
4. Insure the combustion air inlet pipe (for a 2
pipe installation) has a 90 degree termina-
tion elbow as shown in Figures 19 and 20.
Note that a combustion air intake must be
provided with an elbow opening downward.
The screen provided with the furnace must be
installed in the elbow to prevent entry of debris
or creatures.
When the vent pipe must exit an exterior wall
closetothegradeorexpectedsnowlevel,ariser
should be provided as shown in Figure 18.
Insulation is required to prevent freezing of this
section of pipe.
Vertical Venting
Figure 20 shows the proper installation and clear-
ancesforverticalventtermination. Theroofpenetra-
tionmustbeproperlyflashedandwaterproofedwith
a plumbing roof boot or equivalent flashing. Termi-
nationspacingrequirementsfromtheroofandfrom
each other must be per Figure 20.
Ventandcombustionairpipingmay beinstalled
in an existing chimney which is not in use
provided that:
a. Both the exhaust vent and air intake run
the length of the chimney.
b. The top of the chimney is sealed and
weatherproofed.
c. The termination clearances shown in
Figure 20 are maintained.
d. Noothergasfiredappliancesarevented
through the chimney.
Vent Freezing Protection
When the vent pipe is exposed to temperatures
below freezing, i.e., when it passes through
unheatedspaces, chimneys,etc.,thepipe must
be insulated with 1/2 inch thick sponge rubber
insulation, Armaflex-type insulation or equiva-
lent. Insulating pipe is important to avoid con-
densate icing.
For extremely cold climates or for conditions of
short furnace cycles (i.e. set back thermostat
conditions)thelastthreefeetofventpipecanbe
reducedonenominalpipesizeprovidedthatthe
total vent length is at least 15 feet in length and
the vent is sized in accordance with the venting
requirements (Table 5) before this reduction is
applied. (Example: 3" to 2-1/2" or 2" to 1-1/2")
Smallerventpipesare lesssusceptibletofreez-
ing, but must not be excessively restrictive.
Concentric Vent Termination
A concentric vent termination is approved for
use with these furnaces. The kit part number is
903578. Forproperinstallationoftheconcentric
vent termination, follow the installation instruc-
tions provided with that kit.
36" max.
18" min.
ExhaustVent
Option B
ExhaustVent
Option A
ExhaustVent
Option C
Mounting Kit
Faceplate Secured
toWall with Screws
18" Min.
36" Max.
7" Min.
8" Min.
12" Min. to
Normal Snow Level
Combustion
Air Inlet
Grade
Level
or Normal
Snow
Inlet Exhaust
18" Min.
36" Max.
Figure 19. Exhaust and Combustion Air Pipe Clearances