Lennox G26 Series User manual

11/00
*2P1100*
504,228M
*P504228M*
Page 1
E 2000 Lennox Industries Inc.
Dallas, Texas, U A
IN TALLATION
IN TRUCTION
G26 SERIES UNITS
GAS UNITS
504,228M
11/2000
upersedes 503,885M
Table of Contents
Unit Dimensions 2. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
G26 Parts Identification 3. . . . . . . . . . . . . . . . . . . . . . . . .
Requirements 4. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
General 4. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Installation - etting Equipment 5. . . . . . . . . . . . . . . . . .
Return Air Opening Guidelines 5. . . . . . . . . . . . . . . . . . .
Filters & Optional Filter Assembly 6. . . . . . . . . . . . . . . .
Duct ystem 7. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Pipe & Fittings pecifications 7. . . . . . . . . . . . . . . . . . . .
Vent Piping Guidelines 8. . . . . . . . . . . . . . . . . . . . . . . . . .
Joint Cementing Procedure 8. . . . . . . . . . . . . . . . . . . . . .
Venting Practices 9. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Gas Piping 15. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Electrical 16. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Unit tart-Up 20. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Gas Pressure Adjustment 21. . . . . . . . . . . . . . . . . . . . . .
High Altitude Information 22. . . . . . . . . . . . . . . . . . . . . . .
Other Unit Adjustments 22. . . . . . . . . . . . . . . . . . . . . . . .
ervice 23. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Repair Parts 26. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Troubleshooting 26. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
tart-Up & Performance Check List 31. . . . . . . . . . . . . .
RETAIN THESE INSTRUCTIONS
FOR FUTURE REFERENCE
WHAT TO DO IF YOU SMELL GAS:
Do not sto e o use gasoline o othe
flammable vapo s and liquids in the viĆ
cinity of this o any othe appliance.
Installation and se vice must be pe -
fo med by a qualified installe , se vice
agency o the gas supplie .
DDo not t y to light any appliance.
DDo not touch any elect ical switch; do not use
any phone in you building.
DImmediately call you gas supplie f om a
neighbo 's phone. Follow the gas supplie 's
inst uctions.
DIf you cannot each you gas supplie , call the
fi e depa tment.
DExtinguish any open flames.
If the info mation in this manual is not
followed exactly, a fi e o explosion
may esult causing p ope ty damage,
pe sonal inju y o death.
WARNING
Litho U. .A.
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Page 2
G26 Unit Dimensions - inches (mm)
AIR FLOW
SUPPLY
AIR
OPENING
4 (102)
1 1/16
(41)
A
B
E
Retu n Ai
Knockout (Bottom)
GAS PIPING
INLET
(Both Sides)
18 7/8
(479)
ELECTRICAL
INLETS
(Both Sides)
RETURN AIR
KNOCKOUT
(Eithe Side)
28 1/2
(724)
C
23 (584)
1Ć15/16 (49)
F
TOP VIEW
FRONT VIEWSIDE VIEW
1 1/16
(41)
46
(1168)
2 1/2 (64)
2
(51)
3 5/8
(92)
23
(584)
4 1/2
(114)
CONDENSATE
DRAIN
(Both Sides)
EXHAUST
AIR OUTLET
COMBUSTION
AIR INTAKE
21 3/4
(552)
7 3/8
(187)
23 3/4 (603)
25 (635)
5/8
(16)
H
G
5/8 (16)
EXTERNAL
SIDE RETURN
AIR FILTER KIT
(Eithe Side)
(Optional)
23 (584) D
Retu n Ai
Knockout (Bottom)
4 (102)
Model No
A B C D E F G H
Model No. in. mm in. mm in. mm in. mm in. mm in. mm in. mm in. mm
G26Q2-50
G26Q3Ć50
G26Q3Ć75
16Ć1/4 413 14Ć1/8 359 12 305 12 305 2Ć1/8 54 7Ć5/8 194 14 356 12Ć3/4 324
G26Q3/4Ć100
G26Q4/5-75
G26Q4/5Ć100
21Ć1/4 540 19Ć1/8 486 18 457 18 457 1Ć5/8 41 10Ć1/8 257 20 508 18Ć3/4 476
G26Q3/4-125
G26Q4/5Ć125 26Ć1/4 667 24Ć1/8 613 18 457 18 457 4Ć1/8 105 12Ć5/8 321 20 508 18Ć3/4 476
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Page 3
G26 Pa ts A angement
G26 PARTS IDENTIFICATION
FIGURE 1
TOP CAP
CABINET
GLA FIBER GA KET
FRE H AIR
INTAKE FITTING
BURNER BOX
A EMBLY
PATCH
PLATE
PATCH PLATE WITH
BARBED FITTING
AND FLAME
ROLL-OUT WITCH
GA VALVE AND
MANIFOLD
BURNER
BOX
COVER
FLAME IGHT
GLA
DuralokPlusTM
HEAT EXCHANGER
A EMBLY
CONDEN ER COIL
CONTROL TRAN FORMER
CONTROL BOX COVER
DOOR INTERLOCK WITCH
CONTROL VOLTAGE
CIRCUIT BREAKER
WARM
HEADER
(COLLECTOR)
BOX
COLD HEADER
(COLLECTOR)
BOX
COMBU TION AIR
INDUCER
COMBU TION AIR
ORIFICE
BLOWER
ACCE
DOOR
BURNER
ACCE
PANEL
FLUE
TRAN ITION
COMBU TION AIR
PROVE
(PRE URE)
WITCH
UPPLY
AIR
BLOWER
PRIMARY LIMIT
(ALTERNATE TYLE )
FLUE COLLAR
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Page 4
Requi ements
All G26 units are C A International certified to AN I
Z21.47 and C A 2.3 standards.
In the U A, installation of Lennox gas central furnaces must
conform with local building codes. In the absence of local
codes, units must be installed according to the current NaĆ
tional Fuel Gas Code (AN I-Z223.1) in the United tates.
The National Fuel Gas Code is available from the following
address:
American National tandards Institute, Inc.
11 West 42nd treet
New York, NY 10036
In Canada, installation must conform with current National
tandard of Canada CAN/CGA-B149.1 Installation Code
for Natural Gas Burning Appliances and Equipment" and
CAN/CGA-B149.2 Installation Code for Propane Gas
Burning Appliances and Equipment," local plumbing or
waste water codes and other applicable local codes.
Adequate clearance must be made around the air openĆ
ings into the vestibule area. Provisions must be made for
proper operation and for combustion air and ventilation air
supply according to the current National Fuel Gas Code or
CAN/CGA-B149 standards.
This furnace is C A International certified for installation
clearances to combustible material as listed on the unit rating
plate and in table 1.
TABLE 1
Clea ances Location Inches (mm)
Front 24 (610)
ervice access Condensate side 3 (76)
(from side of unit)
Top 1 (25)
To combustible Exhaust 0
To
combustible
materials ide, rear, and front 0
Floor 0*
*Appliance shall not be installed directly on carpeting, tile or other combustible mateĆ
rial other than wood flooring.
NOTE- ervice access clearance must be maintained.
NOTE - For installation on combustible floors, the furnace shall
not be installed directly on carpeting, tile, or other combustible
material other than wood flooring.
Accessibility and service clearances must take preceĆ
dence over fire protection clearances.
For installation in a residential garage, the furnace must be
installed so that the burner(s) and the ignition source are loĆ
cated no less than 18 inches (457 mm) above the floor. The
furnace must be located or protected to avoid physical dam-
age by vehicles. When a furnace is installed in a public garage,
hangar, or other building that has a hazardous atmosphere,
the furnace must be installed according to recommended
good practice requirements and current National Fuel Gas
Code or CAN/CGA B149.1 and B149.2 standards.
The furnace must be adjusted to obtain a temperature rise
within the range specified on the unit rating plate.
When installed, the furnace must be electrically grounded
according to local codes. In addition, in the United tates,
installation must conform with the current National Electric
Code, AN I/NFPA No. 70. The National Electric Code
(AN I/NFPA No. 70) is available from the following ad-
dress:
National Fire Protection Association
1 Battery March Park
Quincy, MA 02269
Wiring to be done in the field, between the furnace and deĆ
vices not attached to the furnace or between separate deĆ
vices which are field-installed and located, shall conform
with the temperature limitation for type T wire [63°F (17°C)
rise] when installed in accordance with these instructions.
G26 unit must be installed so that electrical components
are protected from water.
When the furnace is installed so that supply ducts carry air
circulated by the furnace to areas outside of the space conĆ
taining the furnace, return air shall be handled by a duct(s)
sealed to the furnace casing and terminating out-side
space containing furnace.
WARNING
P oduct contains fibe glass wool.
Distu bing the insulation in this p oduct du ing
installation, maintenance, o epai will expose you
to fibe glass wool dust. B eathing this may cause
lung cance . (Fibe glass wool is known to the State
of Califo nia to cause cance .)
Fibe glass wool may also cause espi ato y, skin,
and eye i itation.
To educe exposu e to this substance o fo fu the
info mation, consult mate ial safety data sheets
available f om add ess shown below, o contact you
supe viso .
Lennox Indust ies Inc.
P.O. Box 799900
Dallas, TX 75379-9900
NOTE - G26 series units must not be used as a construcĆ
tion heater during any phase of construction. Very low re-
turn air temperatures, harmful vapors and misplacement of
the filters will damage the unit and lower its efficiency.
Gene al
These instructions are intended as a general guide and do not
supersede local codes in any way. Consult authorities having
jurisdiction before installation.
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Page 5
Shipping and Packing List
1 - Assembled G26 furnace
1 - Bag assembly containing
1 - Electrical make-up box
1 - Wiring harness
1 - nap bushing
2 - Filter clips
1 - 3 inch x 2 inch vent transition piece (-100, -125 units
only)
1 - Adapter
1 - Condensate plug
1 - Nipple
1 - Brown accessory wire
1 - Green ground wire
3 - Wire nuts
2 - tar washers
Shipping Damage
Check equipment for shipping damage. If you find any
damage, immediately contact the last carrier.
WARNING
Imp ope installation, adjustment, alte ation, se vice
o maintenance can cause p ope ty damage, pe sonĆ
al inju y o loss of life. Installation and se vice must
be pe fo med by a qualified installe , se vice agency
o the gas supplie .
CAUTION
As with any mechanical equipment, pe sonal inju y
can esult f om contact with sha p sheet metal
edges. Be ca eful when you handle this equipment.
Installation - Setting Equipment
elect a location that allows for required clearances
listed on the unit rating plate. Also consider gas supply
connections, electrical supply, vent connection and
installation and service clearances [24 inches (610 mm)
at unit front]. The furnace must be level.
NOTE - 1/3 and 1/2 hp blower motors are equipped with eiĆ
ther four flexible mounting legs or three flexible legs and
one rigid leg. The rigid leg is equipped with a shipping bolt
and a flat white plastic washer (rather than the rubber
mounting grommet used with a flexible mounting leg). This
shipping bolt and flat washer must be removed before the
furnace is put into operation. Once the shipping bolt and
washer are removed, the rigid leg will not touch the blower
housing.
CAUTION
G26 unit should not be installed in a eas no mally
subject to f eezing tempe atu es.
Retu n Ai Opening Guidelines
WARNING
Blowe doo must be secu ely in place when blowe
and bu ne s a e ope ating. Gas fumes, which could
contain ca bon monoxide, can be d awn into living
space esulting in pe sonal inju y o death.
WARNING
Imp ope installation of unit can esult in pe sonal inĆ
ju y o death. Combustion and flue p oducts must
neve be allowed to ente the etu n ai system o ai
in the living space. Use sheet metal sc ews and joint
tape to seal etu n ai system to fu nace.
In platfo m installations with fu nace etu n, the fu Ć
nace should be sealed ai tight to the etu n ai pleĆ
num. A doo must neve be used as a po tion of the
etu n ai duct system. The base must p ovide a
stable suppo t and an ai tight seal to the fu nace. AlĆ
low absolutely no sagging, c acks, gaps, etc.
Fo no eason should etu n and supply ai duct sysĆ
tems eve be connected to o f om othe heat-ing deĆ
vices such as a fi eplace o stove, etc. Fi e, exploĆ
sion, ca bon monoxide poisoning, pe sonal inju y
and/o p ope ty damage could esult.
Return air can be brought in either side or at the bottom of
the unit. cribe lines show the outline of each side and the
bottom return air opening.
Bottom Retu n Ai Applications
If cold air return is to terminate through the floor under the
furnace, a direct, airtight and sealed connection must be
made to the bottom of the furnace.
1 - Cut opening in floor or platform. Using knockouts proĆ
vided, cut bottom of base panel. ee figure 2.
FIGURE 2
KNOCKOUT PATTERN FOR BOTTOM
RETURN AIR APPLICATION
2 - Bend a flange on return air plenum and lower into floor
or platform opening. ee figure 3.
3 - Position unit over return air opening. eal unit air tight
with return air plenum.
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Page 6
FIGURE 3
G26 UNIT
SUPPLY AIR
PLENUM
PROPERLY
SIZED FLOOR
OPENING
BOTTOM RETURN AIR APPLICATION
NOTE - Be careful not to damage glass fiber insulation.
Check for tight seal.
Side Retu n Ai Applications
For installations where the return air is taken from a return
air drop, unit may be installed using either the left or right
side of furnace.
For side return air applications, cut furnace cabinet at the
dimensions given on page 2. Embossed corners are proĆ
vided on both cabinet sides for return air opening location.
Filte s & Optional Filte Assembly
This unit is not equipped with a filter. Filter racks and re-
usable foam filters are available from Lennox in single
kits (44J20 for 14 x 25 filters; 44J21 for 20 x 25 filters) or
10-pack kits (66K61 for 14 x 25 filters; 66K62 for 20 x 25
filters). A filter must be in place anytime the unit is in opĆ
eration.
Bottom Retu n Ai Applications
1 - Remove blower access panel.
2 - Install filter clips, provided with unit, by slipping folded
section of clip on edge of bottom opening. ee figure 4.
3 - Place filter in bottom of blower compartment beneath
rear filter clip. Press down on filter sides. Filter clips flex
allowing filter to snap into place.
4 - To remove filter, press clip and pull filter up and out.
FIGURE 4
BOTTOM RETURN FILTER INSTALLATION
FURNACE
BASE BOTTOM
REAR FILTER CLIP
RETURN AIR OPENING
SIDE FILTER CLIPS (2)
FURNACE
FRONT
FURNACE
BACK
Side Retu n Ai Applications
An external filter rack, ordered separately, is available from
Lennox.
NOTE - The filter door may be shipped in the rack behind
the filter. If necessary, remove the filter, retrieve the door
and continue with the installation of the rack.
1 - Align filter rack opening with the inside edge of the side
return opening. Bottom of rack should be approxiĆ
mately 1 inches (25mm) from the bottom and 3 inch-es
(76mm) from the front of the unit.
2 - crew filter rack into place with the eight self-drilling,
self-tapping screws provided. ee figure 5.
3 - Push filter door pins through the two holes in filter door
from the inside of the u-channel. ee figure 6.
4 - Position filter door on end of filter so that the thumb tab
side of the filter door is away from the furnace. queeze
thumb tabs to secure filter to door.
FIGURE 5
SIDE RETURN FILTER INSTALLATION
RETURN
AIR
OPENING
12 in. (305) fo
14 in. (356) Filte
18 in. (457) fo
20 in. (508) Filte
1-15/16 in.
(49)
BLOWER DECK
15/16 in.
(24)
CABINET BASE BOTTOM
RETURN AIR
PLENUM SIZE
12-3/4 in. X 23-1/2 in. (324 X 597)
fo 14 in. (356) Filte
18-3/4 in. x 23-1/2 in. (476 x 597)
fo 20 in. (508) Filte
FIGURE 6
FILTER DOOR ASSEMBLY
FILTER DOOR
PINS
FILTER DOOR
FILTER
FILTER DOOR
PIN TAB
TAB
5 - Guide filter and filter door into the filter rack installed on
side of furnace. Push door into filter rack until secure.
6 - To remove filter, pull filter door pins until door is re-
leased from filter rack.
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Page 7
Duct System
Use industry-approved standards to size and install the
supply and return air duct system. This will result in a quiet
and low-static system that has uniform air distribution.
Supply Ai Plenum
Furnaces installed without a cooling coil require the installaĆ
tion of a removable access panel in the supply air duct. The
access panel should be large enough to permit inspection (eiĆ
ther by smoke or reflected light) of the heat exchanger for
leaks after installation. The furnace access panel must al-
ways be in place when the furnace is operating and it must
not allow leaks into the supply air duct system.
Retu n Ai Plenum
ee dimension illustration on page 2 for proper return air
duct size.
NOTE - For bottom return air, return air duct should be seĆ
cured to the unit using rivets or Ćlocks. For side return air,
secure return air duct to filter rack using screws. When usĆ
ing screws, take care to avoid interference with the filter
which may cause improper filtration.
The etu n ai must not be d awn f om a oom whe e
anothe gas appliance (ie., a wate heate ) is installed.
Even though this furnace draws its combustion air from
outside of the structure, other gas appliances that share a
utility room may not. When return air is drawn from a room,
a negative pressure is created in the room. If a gas apĆ
pliance is operating in a room with negative pressure, the
flue products can be pulled back down the vent pipe and
into the room. This reverse flow of the flue gas may result in
incomplete combustion and the formation of carbon monĆ
oxide gas. This toxic gas might then be distributed through
the house by the furnace duct system.
Pipe & Fittings Specifications
CAUTION
Solvent cements fo plastic pipe a e flammable liqĆ
uids and should be kept away f om all sou ces of
ignition. Do not use excessive amounts of solvent
cement when making joints. Good ventilation should
be maintained to educe fi e haza d and to minimize
b eathing of solvent vapo s. Avoid contact of ceĆ
ment with skin and eyes.
All pipe, fittings, primer and solvent cement must conĆ
form with American National tandard Institute and the
American ociety for Testing and Materials (AN I/
A TM) standards. The solvent shall be free flowing and
contain no lumps, undissolved particles or any foreign
matter that adversely affects the joint strength or chemiĆ
cal resistance of the cement. The cement shall show no
gelation, stratification, or separation that cannot be reĆ
moved by stirring. Refer to the table 2 below for approved
piping and fitting materials.
TABLE 2
PIPING AND FITTINGS SPECIFICATIONS
PIPE & FITTING MATERIAL ASTM
SPECIFICATION
chedule 40 PVC (Pipe) D1785
chedule 40 PVC (Cellular Core Pipe) F891
chedule 40 PVC (Fittings) D2466
chedule 40 CPVC (Pipe) F441
chedule 40 CPVC (Fittings) F438
DR-21 PVC (Pipe) or DR-26 PVC (Pipe) D2241
DR-21 CPVC (Pipe) or DR-26 CPVC (Pipe) F442
chedule 40 AB (Pipe) D1527
chedule 40 AB (Fittings) D2468
AB -DWV (Drain Waste & Vent)
(Pipe & Fittings) D2661
PVC-DWV (Drain Waste & Vent -
Pipe & Fittings) D2665
NOTE - When a WTKX termination kit (30G79) is installed
as part of the intake and exhaust piping, add twelve feet to
the equivalent length of the pipe (the two 2 inch diameter
90° elbows and the 27 inch pipe in the kit).
Primers and solvents must meet A TM specifications. PVC
primer is specified in A TM F 656. Use PVC solvent cement
as specified in A TM D 2564 and AB solvent cement as
specified in A TM D 2235. Low temperature solvent cement
is recommended. Metal or plastic strapping may be used for
vent pipe hangers.
Table 3 lists the available exhaust termination kits. All LenĆ
nox vent terminations are PVC.
TABLE 3
TERMINATION KITS
Lennox Pa t No. Kit LB# Desc iption-Inches (mm)
3" (76.2) Wall
Assembly Termination Kit
3" (76.2) Roof
Termination Kit
2" (50.8) Wall Ring Kit
2" (50.8) Wall
Assembly Termination Kit
2" (50.8) Roof
Termination Kit
2" (50.8) Concentric
Termination Kit
2" (50.8) Wall
Termination Extended Vent
2" (50.8) Wall
Termination Extension Riser
60G77
15F75
22G44
15F74
44J41
44J40
30G28
30G79
LB-49107CE
LB-49107CC
LB-49107CD
LB-49107CB
LB-65678A
LB-65701A
WTK
WTKX
2" (50.8) Low Pressure Drop
Concentric Term. Kit
33K97 LB-87942
When making AB joints, pieces can be prepared with a
cleaner. When joining AB to PVC materials, use PVC solĆ
vent cement. Refer to this procedure as specified in A TM
D3138.
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Page 8
Vent Piping Guidelines
Pipe used for exhaust and intake lines should be sized acĆ
cording to table 4. Note that maximum length of vent pipe is
for one run; either intake or exhaust. Maximum vent length
given is not the total length of intake + exhaust vents.
Each 90° elbow is equivalent to 5 feet (1.52m) of vent pipe.
Two 45° elbows are equivalent to one 90° elbow. One
45°elbow is equal to 2.5 feet (.76m) of vent pipe.
If intake and exhaust piping runs are not equal in length and
number of elbows, the larger diameter pipe must be used
for both runs.
TABLE 4
VENT PIPE SIZING TABLE FOR G26 FURNACES
MINIMUM DIAMETER OF INTAKE/EXHAUST PIPE
Vent Pipe
Equivalent Length
Max. Feet (Mete s)
G26-50
50,000
BTU
G26-75
75,000
BTU
G26-100
100,000
BTU
G26-125
125,000
BTU
15 (4.57m) 1-1/2" 2" 2" 2"
20 (6.10m) 2" 2" 2" 3"
25 (7.62m) 2" 2" 2" 3"
30 (9.14m) 2" 2" 3" 3"
40 (12.19m) 2" 2" 3" 3"
50 (15.24m) 2" 2" 3" 3"
55 (16.76m) 2" 2" 3" 3"
60 (18.29m) 3" 3" 3" 3"
70 (21.34m) 3" 3" 3" 3"
80 (24.38m) 3" 3" 3" 3"
90 (27.43m) 3" 3" 3" 3"
100 (30.48m) 3" 3" 3" 3"
110 (33.53m) 3" 3" 3" 3"
120 (36.58m) 3" 3" 3" 3"
130 (39.62m) 3" 3" 3" --
NOTE - M inch pipe for G26-50 is 5 feet and 2 elbows of 1.5 inch diameter
pipe.
NOTE - M inch pipe for G26-75 is 5 feet and 2 elbows of 2 inch diameter
pipe.
NOTE - M inch pipe for G26-100 is 5 feet and 2 elbows of 2 inch diameter
pipe.
NOTE - M inch pipe for G26-125 is 5 feet and 2 elbows of 2 inch diameter
pipe.
NOTE - When a WTKX termination kit is installed as part of
the intake and exhaust piping, the two 2 inch diameter 90°
elbows and the 27 inch pipe (in the kit) should be included
in the maximum vent pipe length for each run.
For -50 and -75 kBtuh units, connections are provided for 2
inch diameter venting which should satisfy most venting reĆ
quirements. No transition pieces are provided or needed
for 2 inch venting.
For -100 and -125 kBtuh units, the intake connection is
sized for 3 inch diameter pipe. The exhaust connection has
a 2 inch nipple. A pipe transition piece is shipped with the
unit to connect to 3 inch pipe. ee figure 7 for 2 inch and 3
inch venting applications.
Most venting applications will require 3 inch venting for
proper unit operation. Fo no eason should the intake
and exhaust pipe be diffe ent diamete pipes. RegardĆ
less of the diameter of pipe used, the standard roof and wall
terminations described in section Intake and Exhaust PipĆ
ing Terminations should be used. Exhaust piping must terĆ
minate with 1-1/2 inch pipe for 1-1/2 inch or 2 inch venting
and 2 inch pipe for 3 inch venting.
FIGURE 7
G26-100 OR -125 WITH 2 IN. VENTING
G26-100 OR -125 WITH 3 IN. VENTING
3 IN.
IN
2 IN
OUT
3 IN. FIELD
PROVIDED
NIPPLE
2 IN. VENT PIPE
3 IN.
IN
2 IN.
OUT
3 IN. VENT PIPE
3 IN. X 2 IN.
REDUCER
2 IN. FIELD
PROVIDED
NIPPLE
3 IN. X 2 IN.
REDUCER
Joint Cementing P ocedu e
All cementing of joints should be done according to the
specifications outlined in A TM D 2855.
WARNING
DANGER OF EXPLOSION! Fumes f om pvc glue may
ignite du ing system check. Remove spa k plug wi e
f om ignition cont ol befo e 115v powe is applied.
Reconnect wi e afte two minutes.
1 - Measure and cut vent pipe to desired length.
2 - Debur and chamfer end of pipe, removing any ridges
or rough edges. If end is not chamfered, edge of pipe
may remove cement from fitting socket and result in a
leaking joint.
3 - Clean and dry surfaces to be joined.
4 - Test fit joint and mark depth of fitting on outside of pipe.
5 - Uniformly apply liberal coat of PVC primer for PVC or
AB cleaner for AB to inside socket surface of fitting
and male end of pipe to depth of fitting socket.
6 - Promptly apply solvent cement to end of pipe and in-
side socket surface of fitting. Cement should be ap-
plied lightly but uniformly to inside of socket. Take care
to keep excess cement out of socket. Apply second
coat to end of pipe.
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Page 9
NOTE - Time is critical at this stage. Do not allow primĆ
er to dry before applying cement.
7 - Immediately after applying last coat of cement to pipe,
and while both inside socket surface and end of pipe
are wet with cement, forcefully insert end of pipe into
socket until it bottoms out. Turn pipe 1/4 turn during asĆ
sembly (but not after pipe is fully inserted) to distribute
cement evenly.
NOTE-Assembly should be completed within 20 secĆ
onds after last application of cement. Hammer blows
should not be used when inserting pipe.
8 - After assembly, wipe excess cement from pipe at end
of fitting socket. A properly made joint will show a
bead around its entire perimeter. Any gaps may indiĆ
cate a defective assembly due to insufficient solvent.
9 - Handle joints carefully until completely set.
Venting P actices
The thickness of construction through which vent/air intake
pipes may be installed is a minimum of 3 inches (610 mm),
and a maximum of 24 inches (610mm). If a G26 furnace re-
places a furnace which was commonly vented with another
gas appliance, the size of the existing vent pipe for that gas
appliance must be checked. Without the heat of the original
furnace flue products, the existing vent pipe is probably
oversized for the single water heater or other appliance.
The vent should be checked for proper draw with the reĆ
maining appliance.
WARNING
Insufficient combustion ai can cause headaches,
nausea, dizziness o asphyxiation. It will also cause
excess wate in the heat exchange esulting in ustĆ
ing and p ematu e heat exchange failu e. Excessive
exposu e to contaminated combustion ai will esult
in safety and pe fo mance elated p oblems. Avoid
exposu e to the following substances in the comĆ
bustion ai supply:
Pe manent wave solutions
Chlo inated waxes and cleane s
Chlo ine base swimming pool chemicals
Wate softening chemicals
De-icing salts o chemicals
Ca bon tet achlo ide
Halogen type ef ige ants
Cleaning solvents (such as pe chlo oethylene)
P inting inks, paint emove s, va nishes, etc.
Hyd ochlo ic acid
Cements and glues
Antistatic fab ic softene s fo clothes d ye s
Mason y acid washing mate ials
Intake Piping
1 - Cement intake piping in slip connector located at top
of unit.
2 - Route piping to outside of structure. Continue with
installation following instructions given in exhaust and
intake piping termination section.
Exhaust Piping
1 - Cement exhaust piping into flue collar socket located
on the left side of the top cap.
2 - All horizontal runs of exhaust pipe must slope back to-
ward unit. A minimum of a 1/4 inch (6mm) drop for each
12 inches (305mm) of horizontal run is mandatory for
drainage. Horizontal runs of exhaust piping must be
supported every 5 feet (1.52m) using hangers.
NOTE - Exhaust piping should be checked carefully to
make sure there are no sags or low spots.
NOTE - Exhaust piping must be insulated with 1/2 inch
(13mm) Armaflex or equivalent when run through unĆ
heated space. Do not leave any area of exhaust pipe
open to outside air; exterior exhaust must be insulated
with 1/2 inch (13mm) Armaflex or equivalent.
CAUTION
Do not discha ge exhaust into an existing stack o
stack that also se ves anothe gas appliance. If ve tiĆ
cal discha ge th ough an existing unused stack is eĆ
qui ed, inse t PVC pipe inside the stack until the end
is even with the top o outlet end of the metal stack.
CAUTION
The exhaust vent pipe ope ates unde positive p esĆ
su e and must be completely sealed to p event leakĆ
age of combustion p oducts into the living space.
Removal of Unit f om Common Venting System
In the event that an existing furnace is removed from a
venting system commonly run with separate gas apĆ
pliances, the venting system is likely to be too large to propĆ
erly vent the remaining attached appliances. The following
test should be conducted while all appliances (both in opĆ
eration and those not in operation) are connected to the
common venting system. If the venting system has been
installed improperly, corrections must be made as outlined
in the previous section.
1 - eal any unused openings in the common venting sysĆ
tem.
2 - Visually inspect the venting system from proper size
and horizontal pitch and determine there is no block-
age or restriction, leakage, corrosion and other defiĆ
ciencies which could cause an unsafe condition.
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Page 10
3 - Close all building doors and windows and all doors beĆ
tween the space in which the appliances remaining
connected to the common venting system are located
and other spaces of the building. Turn on clothes dryĆ
ers and any appliances not connected to the common
venting system. Turn on any exhaust fans, such as
range hoods and bathroom exhausts, so they will opĆ
erate at maximum speed. Do not operate a summer
exhaust fan. Close fireplace dampers.
4 - Follow the lighting instruction. Place the appliance beĆ
ing inspected in operation. Adjust thermostat so apĆ
pliance will operate continuously.
5 - Test for spillage at the draft hood relief opening after 5
minutes of main burner operation. Use the flame of a
match or candle, or smoke from a cigarette, or a cigar.
6 - After you have determined that each appliance reĆ
maining connected to the common venting system
properly vents when tested as outlined above, return
doors, windows, exhaust fans, fireplace dampers and
any other gas-burning appliance to their previous conĆ
dition of use.
7 - If improper venting is observed during any of the
above tests, the common venting system must be corĆ
rected. The common venting system should be re-
sized to approach the minimum size as determined by
using the appropriate tables in appendix G in the cur-
rent standards of the National Fuel Gas Code AN I
Z223-1 in the U. .A., and the appropriate Category 1
Natural Gas and Propane appliances venting sizing
tables in the current standards of the CAN/
CGA-B149.1 and .2 in the Natural Gas and Propane
Installation Code in Canada.
Intake and Exhaust Piping Te minations
Intake and exhaust pipes may be routed either horizontally
through an outside wall or vertically through the roof. In at-
tic or closet installations, vertical termination through the
roof is preferred. Figures 8 through 20 show typical terĆ
minations.
1 - Use recommended piping materials for both intake
and exhaust piping.
2 - ecure all joints, including drain leg, gas tight using
approved cement.
3 - Piping diameters should be determined according to
length of pipe run. ee table 4. Locate intake piping
upwind (prevailing wind) from exhaust piping. To avoid
re-circulation of exhaust gas on roof terminations, end
of exhaust pipe must be higher than intake pipe.
Exhaust and intake exits must be in same pressure
zone. Do not exit one through the roof and one on the
side. Also, do not exit the intake on one side and the
exhaust on another side of the house or structure.
4 - Intake and exhaust pipes should be placed as close
together as possible at termination end (refer to ilĆ
lustrations). Maximum separation is 3 inches (76mm)
on roof terminations and 6 inches (152mm) on side
wall terminations.
5 - Exhaust piping must terminate straight out or up as
shown. In rooftop applications, a 2 inch X 1-1/2 inch reĆ
ducer for 2 inch venting, 3 inch x 2 inch reducer for 3
inch venting must be used on the exhaust piping at the
point where it exits the structure to improve the velocity
of exhaust away from the intake piping.
On roof terminations, the intake piping should termiĆ
nate straight down using two 90° elbows ( ee figure 8).
IMPORTANT
Do not use sc eens o pe fo ated metal in intake and
exhaust te minations. Doing so will cause f eeze-
ups and may block the te minations.
NOTE - If winter design temperature is below 32°F (0°C),
exhaust piping must be insulated with 1/2 inch (13mm),
Armaflex or equivalent when run through unheated
space. Do not leave any surface area of exhaust pipe
open to out-side air; exterior exhaust pipe must be insuĆ
lated with 1/2 inch (13mm) Armaflex or equivalent. In exĆ
treme cold climate areas, 3/4 inch (19mm) Armaflex or
equivalent is recommended. Insulation on outside runs of
exhaust pipe must be painted or wrapped to protect inĆ
sulation from deterioration.
FIGURE 8
ROOF TERMINATION KIT
(15F75) LB-49107CC fo 2 (51) Venting
(44J41) LB-65678A fo 3 (76) Venting
UNCONDITIONED
ATTIC SPACE
1/2 (13) FOAM
INSULATION IN
UNCONDITIONED
SPACE
3 x 2 (76 x 51) OR
2 x 1-1/2 (51 x 38)
PVC REDUCER
3(76) MAX.
12 (305) ABOVE
AVERAGE SNOW
ACCUMULATION
3 (76) OR
2 (51) PVC
PROVIDE SUPPORT
FOR INTAKE AND
EXHAUST LINES
8 (203) MIN
Inches(mm)
NOTE - During extremely cold temperatures, below
approximately 20°F (6.67°C), units with long runs of vent
pipe through unconditioned space, even when insulated,
may form ice in the exhaust termination that prevents the
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Page 11
unit from operating properly. Longer run times of at least 5
minutes will alleviate most icing problems. Also, a heating
cable may be installed on exhaust piping and termination to
prevent freeze-ups. Heating cable installation kit is avail-
able from Lennox. ee Condensate Piping section for part
numbers.
NOTE - Care must be taken to avoid recirculation of exĆ
haust back into intake pipe.
6 - On field supplied terminations for side wall exits, exĆ
haust piping should extend a maximum of 12 inches
(305mm) beyond the outside wall. Intake piping
should be as short as possible. ee figure 9.
FIGURE 9
1/2 (13) ARMAFLEX
INSULATION IN
UNCONDITIONED SPACE
2 (51) PVC 1-1/2 (38) PVC
12 (305) MIN.
2 X 1-1/2
(51 x 38)
PVC REDUCER
1/2 (13) ARMAFLEX
INSULATION
6 (152)
MAXIMUM
2 (51) PVC
COUPLING
8 (203)
MINIMUM
OUTSIDE
WALL
Inches (mm) TOP VIEW
WALL RING KIT
(15J74) LB-49107CB fo 2 (50.8) Venting
7 - On field supplied terminations, a minimum separation
distance between the end of the exhaust pipe and the
end of the intake pipe is 8 inches (203mm).
8 - If intake and exhaust piping must be run up a side wall
to position above snow accumulation or other obĆ
structions. Piping must be supported every 3 feet
(.91m) as shown in figure 15. Refer to figures 13 and
14 for proper piping method. WTK wall termination kit
must be extended for use in this application. ee figĆ
ure 18 or use kit WTKX shown in figure 19. When exĆ
haust and intake piping must be run up an outside
wall, the exhaust piping is reduced to 1-1/2 inches
(38mm) after the final elbow. The intake piping may
be equipped with a 90° elbow turndown. Using turnĆ
down will add 5 feet (1.5m) to the equivalent length of
the pipe.
FIGURE 10
TOP VIEW
WALL TERMINATION
(22G44) LB-49107CD fo 2 (50.8) Venting
(44J40) LB-65701A fo 3 (76.2) Venting
Inches(mm)
OUTSIDE WALL
1/2 (12.7) FOAM INSULATION
IN UNCONDITIONED SPACE
Optional Tu ndown
Shown
(Intake Only)
FIGURE 11
12 (305) ABOVE
AVERAGE SNOW
ACCUMULATION
EXHAUST
EXHAUST
TERMINATION
INTAKE
TERMINATION
INTAKE
Inches (mm)
CONCENTRIC ROOFTOP TERMINATION
(60G77) LB-49107CE fo G26-50 & -75 Units Only
(33K97) LB-87942 fo G26-100 & -125 Units Only
FIGURE 12
EXHAUST
EXHAUST
TERMINATION
INTAKE
TERMINATION
INTAKE 12 (305) Min.
above g ade.
CONCENTRIC WALL TERMINATION
(60G77) LB-49107CE fo G26-50 & -75 Units Only
(33K97) LB-87942 fo G26-100 & -125 Units Only
Inches (mm)
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Page 12
FIGURE 13
*This educe is not necessa y fo G26-50 units using 1-1/2 in. venting.
See venting table 4 fo maximum venting lengths with this a angement.
12 (305) ABOVE
AVERAGE SNOW
ACCUMULATION
UNCONDITIONED
SPACE
12 (305) MIN. for 2 (51)
20 (508) MAX. for 3 (76)
8 (203)
MIN.
1/2 (13) FOAM
INSULATION
1/2 (13) FOAM
INSULATION IN
UNCONDITIONED
SPACE
PROVIDE SUPPORT
FOR INTAKE AND
EXHAUST LINES EVERY
36 (914)
OUTSIDE WALL
Inches(mm)
SIDE VIEW
WALL RING TERMINATION
(15F74) LB-49107CB fo 2 in. (51) Venting
9 - Position termination ends so they are free from any obĆ
structions and above the level of snow accumulation
(where applicable). Termination ends must be a mini-
mum of 12 inches (305mm) above grade level. Do not
point into window wells, stairwells, alcoves, courtyard
areas or other recessed areas. Do not position terminaĆ
tion ends directly below roof eaves or above a walkway.
ince the G26 is a certified direct vent, Category IV gas
furnace, the location of the termination is limited by loĆ
cal building codes. In the absence of local codes, refer
to the current National Fuel Gas Code AN I Z223-1 in
U. .A., and current standards CAN/CGA-B149.1 /.2 of
the Natural Gas and Propane Installation Instructions in
Canada for details. The termination should be at least
12 inches (305mm) from any opening through which
flue products could enter the building.
When horizontally vented, minimum clearance for terĆ
mination from electric meters, gas meters, regulators
and relief equipment is 4 feet (1.2m) for U installaĆ
tions. Refer to the current CAN/CGA-B149.1 and .2 for
installations in Canada or with authorities having local
jurisdiction.
At vent termination, care must be taken to maintain
protective coatings over building materials (proĆ
longed exposure to exhaust condensate can destroy
protective coatings). It is recommended that the exĆ
haust outlet not be located within 6 feet (1.8m) of a
condensing unit because the condensate can damĆ
age the painted coating.
IMPORTANT
Combustion ai intake inlet and exhaust outlet should
not be located within 6 feet (1.8m) of d ye vent o comĆ
bustion ai inlet o outlet of anothe appliance. Piping
should not exit less than 3 feet (.91m) f om opening
into anothe building.
IMPORTANT
Fo Canadian Installations Only:
In acco dance to CAN/CGA-B149.1 and .2, the miniĆ
mum allowed distance between the combustion ai
intake inlet and the exhaust outlet of othe apĆ
pliances shall not be less than 12 inches (305mm).
FIGURE 14
Inches (mm)
FRONT VIEW
WALL TERMINATION
(22G44) LB-49107CD fo 2(51) Venting
(44J40) LB-65701A fo 3(76) Venting
3 (76) OR
2 (51) 90° ELBOW
1/2 (13)
FOAM
INSULATION
Inches(mm)
3 (76) OR
2 (51) 90° ELBOW
3 x 2 (76 x 51) OR
2 x 1-1/2 (51 x 38)
REDUCER BUSHING LOCATION
FOR OFFSET TERMINATION
Optional Tu ndown
(Not Shown)
May Be Used on
Intake Only
FIGURE 15
METAL OR PLASTIC
STRAPPING
OR LARGE WIRE TIES
10 - uspend piping using hangers at a minimum of every
5 feet (1.52m) for schedule 40 PVC and every 3 feet
(.91m) for AB -DWV, PVC-DWV, PR-21 PVC, and
DR-26 PVC piping. A suitable hanger can be fabriĆ
cated by using metal or plastic strapping or a large
wire tie.
11 - In areas where piping penetrates joists or interior
walls, hole must be large enough to allow clearance on
all sides of pipe through center of hole using a hanger.
12 - Isolate piping at the point where it exits the outside wall
or roof.
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Page 13
13 - When furnace is installed in a residence where unit is
shut down for an extended period of time, such as a
vacation home, make provisions for draining condenĆ
sate collection trap and lines.
14 - Based on the recommendation of the manufacturer, a
multiple furnace installation may use a group of up to
four termination kits WTK assembled together horizon-
tally, as shown in figure 17.
FIGURE 16
12
(305)
5
(127)
1/2 (13) Foam
Insulation in
Unconditioned Space
EXHAUST VENT
INTAKE VENT
OUTSIDE WALL
EXHAUST VENT
INTAKE
VENT
F ont View
Side View
VENT TERMINATIONS
WALL TERMINATION KIT (30G28) WTK
Inches (mm)
FIGURE 17
EXHAUST
VENT
INTAKE VENT 5-1/2
(140)
F ont View
12
(305)
5
(127)
18 MAX.
(457)
EXHAUST VENT
INTAKE
VENT
Side View
OPTIONAL VENT TERMINATION FOR
MULTIPLE UNIT INSTALLATION
WALL TERMINATION KIT WTK
Inches (mm)
FIGURE 18
12 MIN.
(305)
Above Grade
COVER EXHAUST
VENT WITH
1/2 (13)
FOAM
INSULATION
F ont View
Side View
VENT TERMINATIONS
MODEL WTK WALL TERMINATION KIT (30G28)
EXTENDED VENT FOR GRADE CLEARANCE
Inches (mm)
ÉÉÉÉÉÉÉÉÉ
5
(127)
5Ć1/2
(140)
EXHAUST
AIR
INTAKE
AIR
GRADE
12
(305)
ÉÉÉÉÉÉÉÉÉÉÉ
8 (203)
Minimum
12 (305)
Minimum
ABOVE GRADE
INTAKE
AIR
EXHAUST
AIR
GRADE
FIGURE 19
VENT TERMINATIONS
MODEL WTKX (30G79)
EXTENSION RISER FOR GRADE CLEARANCE
4
(102)
8 MIN.
(203)
EXHAUST VENT
INTAKE
VENT
GRADE
GRADE
EXHAUST
VENT
INTAKE
VENT
34
(864)
12
(305)
9
(229)
NOTE-Enclosed exhaust pipe
is insulated with 1/2 in. (13mm)
foam insulation. If intake and
exhaust pipes are reversed, slit
and remove foam insulation
and reapply to other vent. ExĆ
haust vent must be insulated.
F ont View
Side View
OUTSIDE WALL
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Page 14
G26 VENTING IN EXISTING CHIMNEY
NOTE-Do not discharge exhaust gases directly into any chimney or vent stack. If vertiĆ
cal discharge through an existing unused chimney or stack is required, insert piping
inside chimney until the pipe open end is above top of chimney and terminate as illusĆ
trated. In any exterior portion of chimney, the exhaust vent must be insulated. An alterĆ
nate method is to fill the chimney with vermiculite or equal to take advantage of its
acoustic and thermal properties.
FIGURE 20
8 in. - 12 in.
(203mm - 305mm)
3 in. - 8 in.
(76mm-
203mm)
3 in. - 8 in.
(76mm-
203mm)
Condensate Piping
This unit is designed for either right- or left-side exit of conĆ
densate piping. Condensate drain line should be routed
only within the conditioned space to avoid freezing of conĆ
densate and blockage of drain line. An electric heat cable
should be used where condition is exposed to uncondiĆ
tioned areas.
CAUTION
Do not use coppe tubing o existing coppe condenĆ
sate lines fo d ain line.
1 - Determine which side condensate will exit the unit.
2 - Connect a 1/2 inch (13mm) plastic pipe plug (provided)
in the unused end of the condensate trap. Install plug so
that it is sealed water tight yet able to be removed. Do
not permanently seal the connection. Teflon tape is recĆ
ommended to seal joint. ee figure 21.
CONDENSATE ASSEMBLY
(Fo left o ight installation)
FIGURE 21
COLD HEADER
BOX
NIPPLE
ADAPTER
ADAPTER
NIPPLE PLUG BOOT OR CAP
COMBUSTION AIR
INDUCER BRACKET
CONDENSATE TRAP
3 - Use the provided adapter (1/2 inch PVC x 1/2 inch
MPT) and the nipple (1/2 inch PVC) to carry drainage
outside the cabinet. If a field substitute is needed, 1/2
inch CPVC x 1/2 inch MPT adapter and 1/2 inch CPVC
is acceptable for use.
4 - Glue nipple to the adapter using the procedures out-
lined in the Joint Cementing Procedures" section.
The nipple/adapter assembly should be connected in
a non-permanent manner and must be water tight.
Teflon tape is recommended to seal the joint.
Fo Right-Hand Side Condensate Exit:
Install the nipple/adapter assembly from the outside
of the cabinet and insert the adapter into the threaded
opening in the condensate trap.
Fo Left-Hand Side Condensate Exit:
Insert nipple/adapter assembly from the left hand
side of the cabinet and through the combustion air
inducer mounting structure into the threaded openĆ
ing in the condensate trap.
5 - Connect field supplied plumbing to nipple and route to
open drain. Plumbing should be vented to a point higher
than the condensing coil. ee figure 22.
FIGURE 22
CONDENSATE PLUMBING
(Plumbing must be vented highe than coil.)
6 - Connect condensate drain line (1/2 inch [13mm] DR
11 plastic pipe or tubing) to condensate connection on
drip leg assembly and route to open drain. Conden-
sate line must be sloped downward away from drip leg
to drain. If drain level is above drip leg, condensate
pump must be used to condensate line. Condensate
drain line should be routed within the conditioned
space to avoid freezing of condensate and blockage of
drain line. If this is not possible, a heat cable kit may be
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Page 15
used on the condensate drip leg and line. Heating
cable kit is available from Lennox in various lengths;
6feet (1.8m) - kit no. 18K48; 24 feet (7.3m) - kit no.
18K49; and 50 feet (15.2m) - kit no. 18K50.
Gas Piping
1 - Gas piping may be routed into the unit through either
the left- or right-hand side. upply piping enters into
the gas valve from the bottom of the valve as shown in
figure 23.
FIGURE 23
GAS VALVE
LEFT SIDE PIPING
MANUAL
MAIN SHUT-
OFF
VALVE
RIGHT SIDE PIPING
(STANDARD)
GAS VALVE
1/8 IN. NPT
PLUGGED
TAP
MANUAL
MAIN SHUT-
OFF
VALVE
1/8 IN. NPT
PLUGGED
TAP
2 - When connecting the gas supply, factors such as
length of run, number of fittings and furnace rating
must be considered to avoid excessive pressure drop
Table 5 lists recommended pipe sizes for typical ap-
plications.
NOTE - Use two wrenches when connecting gas pipĆ
ing to avoid transferring torque to the manifold.
3 - The gas piping must not run in or through air ducts,
clothes chutes, gas vents or chimneys, dumb waiters
or elevator shafts. Center gas line through piping hole.
Gas line should not touch side of unit.
When left-hand gas plumbing is required, gas line
should be installed in the lower half of knockout so that
piping will clear combustion air inducer. ee figure 23.
4 - The piping should be sloped 1/4 inch (6.4 mm) per 15
feet (4.57 m) upward toward the meter from the furĆ
nace. The piping must be supported at proper interĆ
vals [every 8 to 10 feet (2.44 to 3.01 m)] using suitable
hangers or straps. A drip leg should be installed in verĆ
tical pipe runs to the unit.
5 - In some localities, codes may require installation of a
manual main shut-off valve and union (furnished by inĆ
staller) external to the unit. Union must be of the
ground joint type.
IMPORTANT
Compounds used on th eaded joints of gas piping
must be esistant to the actions of liquified pet oĆ
leum gases.
FIGURE 24
MANUAL MAIN SHUT-OFF
VALVE WILL NOT HOLD
NORMAL TEST PRESSURE
CAP
FURNACE
ISOLATE
GAS VALVE
1/8 IN. (3.2mm) N.P.T.
PLUGGED TAP
NOTE - Install a 1/8 inch NPT plugged tap in the field pipĆ
ing upstream of the gas supply connection to the unit.
The tap must be accessible for test gauge connection.
ee figure 24.
Leak Check
After gas piping has been completed, carefully check all
piping connections (factory and field) for gas leaks. Use a
leak detecting solution or other preferred means.
CAUTION
Some soaps used fo leak detection a e co osive to
ce tain metals. Ca efully inse piping tho oughly afĆ
te leak test has been completed. Do not use
matches, candles, flame o othe sou ces of ignition
to check fo gas leaks.
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Page 16
TABLE 5
GAS PIPE CAPACITY - FT3/HR (kL/HR)
Nominal Inte nal Length of Pipe-Feet(m)
Nominal
I on Pipe Size
-Inches(mm)
Inte nal
Diamete
-Inches(mm) 10
(3.048)
20
(6.096)
30
(9.144)
40
(12.192)
50
(15.240)
60
(18.288)
70
(21.336)
80
(24.384)
90
(27.432)
100
(30.480)
1/4
(6.35)
.364
(9.246)
43
(1.13)
29
(.82)
24
(.68)
20
(.57)
18
(.51)
16
(.45)
15
(.42)
14
(.40)
13
(.37)
12
(.34)
3/8
(9.53)
.493
(12.522)
95
(2.69)
65
(1.84)
52
(1.47)
45
(1.27)
40
(1.13)
36
(1.02)
33
(.73)
31
(.88)
29
(.82)
27
(.76)
1/2
(12.7)
.622
(17.799)
175
(4.96)
120
(3.40)
97
(2.75)
82
(2.32)
73
(2.07)
66
(1.87)
61
(1.73)
57
(1.61)
53
(1.50)
50
(1.42)
3/4
(19.05)
.824
(20.930)
360
(10.19)
250
(7.08)
200
(5.66)
170
(4.81)
151
(4.28)
138
(3.91)
125
(3.54)
118
(3.34)
110
(3.11)
103
(2.92)
1
(25.4)
1.049
(26.645)
680
(19.25)
465
(13.17)
375
(10.62)
320
(9.06)
285
(8.07)
260
(7.36)
240
(6.80)
220
(6.23)
205
(5.80)
195
(5.52)
1-1/4
(31.75)
1.380
(35.052)
1400
(39.64)
950
(26.90)
770
(21.80)
660
(18.69)
580
(16.42)
530
(15.01)
490
(13.87)
460
(13.03)
430
(12.18)
400
(11.33)
1-1/2
(38.1)
1.610
(40.894)
2100
(59.46)
460
(41.34)
1180
(33.41)
990
(28.03)
900
(25.48)
810
(22.94)
750
(21.24)
690
(19.54)
650
(18.41)
620
(17.56)
2
(50.8)
2.067
(52.502)
3950
(111.85)
2750
(77.87)
2200
(62.30)
1900
(53.80)
1680
(47.57)
1520
(43.04)
1400
(39.64)
1300
(36.81)
1220
(34.55)
1150
(32.56)
2-1/2
(63.5)
2.469
(67.713)
6300
(178.39)
4350
(123.17)
3520
(99.67)
3000
(84.95)
2650
(75.04)
2400
(67.96)
2250
(63.71)
2050
(58.05)
1950
(55.22)
1850
(52.38)
3
(76.2)
3.068
(77.927)
11000
(311.48)
7700
(218.03)
6250
(176.98)
5300
(150.07)
4750
(134.50)
4300
(121.76)
3900
(110.43)
3700
(104.77)
3450
(97.69)
3250
(92.03)
4
(101.6)
4.026
(102.260)
23000
(651.27)
15800
(447.39)
12800
(362.44)
10900
(308.64)
9700
(274.67)
8800
(249.18)
8100
(229.36)
7500
(212.37)
7200
(203.88)
6700
(189.72)
NOTE-Capacity given in cubic feet of gas per hour (kilo liters of gas per hour) and based on 0.60 specific gravity gas.
The furnace must be isolated from the gas supply system
by closing its individual manual shutĆoff valve during any
pressure testing of the gas supply system at pressures less
than or equal to 1/2 psig (3.48 kPa, 14 inches w.c.).
IMPORTANT
When testing p essu e of gas lines, gas valve must
be disconnected and isolated. See figu e 24. Gas
valves can be damaged if subjected to p essu es
g eate than 1/2 psig (3.48 kPa).
Elect ical
A field make-up box is provided for line voltage wiring. Line
voltage wiring to unit is done through the J69 jack from the
field make-up box to plug P69 from the control box. ee figĆ
ures 25 and 26 for make-up box installation.
Figure 28 shows thermostat designations for identificaĆ
tion purposes. Refer to figure 29 for control box arrangeĆ
ment, figure 30 for a detail of the urelightt integrated
control, figure 31 for schematic wiring diagram and trouĆ
bleshooting, and figure 32 for point to point field wiring.
ELECTROSTATIC DISCHARGE (ESD)
P ecautions and P ocedu es
CAUTION
Elect ostatic discha ge can affect elect onic comĆ
ponents. Take p ecautions du ing fu nace installaĆ
tion and se vice to p otect the fu nace's elect onic
cont ols. P ecautions will help to avoid cont ol exĆ
posu e to elect ostatic discha ge by putting the fu Ć
nace, the cont ol and the technician at the same
elect ostatic potential. Neut alize elect ostatic
cha ge by touching hand and all tools on an unĆ
painted unit su face, such as the gas valve o blowĆ
e deck, befo e pe fo ming any se vice p ocedu e.
1 - Install field make-up box on either side, inside or out of
the cabinet. Knockouts are provided in box and cabiĆ
net to run wiring. ee figures 25 and 26.
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Page 17
FIGURE 25
INTERIOR MAKE-UP BOX INSTALLATION
P69 f om
Cont ol Box
J69
MAKE-UP
BOX
BUSHING
FIGURE 26
EXTERIOR MAKE-UP BOX INSTALLATION
P69 f om
Cont ol Box
J69
(Shown with
accesso y
wi e connected)
MAKE-UP
BOX
BUSHING
2 - Remove cap from knockout in blower deck on the
same side as the installed make-up box.
IMPORTANT
Ignition cont ol will not ope ate unless unit is p ope Ć
ly g ounded. 120V supply must be installed with co Ć
ect pola ity.
3 - Electrically ground unit in accordance with local codes
or, in the absence of local codes, in accordance with
the current National Electric Code (AN I/NFPA No.
70) and in Canada with the current Canadian Electric
Code part 1 (C A standard C22.1). The ground wire is
pro-vided in the field make-up box.
To ensure proper grounding of the furnace, two star
washers are included in the electrical make-up box
bag assembly. Place the star washer on securing
screw before installing the make-up box. Make sure
the star washer breaks the paint on the cabinet so
that the washer is touching metal. Unit is not prop-
erly grounded if paint has not been removed by star
washer.
4 - An optional 120 volt accessory wire is provided with
G26 units. Install brown accessory wire into J69 jack
plug by inserting the pin of the brown wire into the open
socket of the jack. ee fig-
ure 27. Any accessory rated
up to 4 amps can be con-
nected to this wire. Connect
the neutral leg of the accesĆ
sory to the neutral white wire
in the make-up box. The acĆ
cessory terminal is enerĆ
gized whenever the blower
is in operation.
5 - Insert the three-pin (P69)
plug from the control box
into the knockout provided in the blower deck.
6 - Connect jack (J69) from make-up box to jack plug in
blower deck.
7 - elect wire size according to the blower motor amps.
8 - naphole bushing is provided for the wiring entry hole
in the cabinet. A snaphole plug is provided to seal the
unused wire entry hole.
9 - Install room thermostat according to instructions pro-
vided with thermostat. ee figure 28 for thermostat desĆ
ignations. If furnace is being used with heat pump refer
to FM21 installation instruction.
10 - Install a separate fused disconnect switch near the
unit so power can be turned off for servicing.
FIGURE 28
COMPRE ORā
COMMON
POWER
HEAT
INDOOR BLOWER
Y
C
R
G
C
R
W
G
COMMON
H UNIT
COMMON
H UNIT
COMPRE OR
Y
C
R
G
C
R
W
G
G26
Fu nace
Condensing UnitThe mostat
G26 and CONDENSING UNIT
THERMOSTAT DESIGNATIONS
(Refe to specific the mostat and outdoo unit.)
COOLING
11 - Complete wiring connections to equipment using wirĆ
ing diagrams provided with unit and in figures 31 and
32. Use 18-gauge wire or larger for thermostat conĆ
nections.
BLACK
WHITE
NEUTRAL
BROWN
J69
INSTALLING BROWN
ACCESSORY WIRE TO J69
FIGURE 27
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Page 18
Indoo Blowe Speeds (Refe to Figu e 31)
1 - When the thermostat is set to FAN ON," the indoor
blower will run continuously on low speed when there
is no cooling or heating demand.
2 - When there is a cooling demand, the indoor blower will
run on the cooling speed.
3 - When there is a heating demand, the indoor blower
will run on the heating speed.
G26 CONTROL BOX
FIGURE 29
CIRCUIT
BREAKER
SURELIGHT
CONTROL
DOOR
INTERLOCK
SWITCH
TRANSFORMER
DETACHABLE
TERMINAL STRIP
SURELIGHT INTEGRATED CONTROL BOARD
FIGURE 30
TERMINAL DESIGNATIONS
ACB COOL
ACB HEAT
PARK
ACB LOW
ACC
TX
HOT
HTG ACC
NEUTRAL
24VAC HOT
24VAC RTN
FLAME EN E
Blower - Cooling peed (Line Volt)
Blower - Heating peed (Line Volt)
Alternate Blower peeds (Dead)
Continuous Low peed Blower
Accessory Terminal (Line Volt)
120VAC Hot to Transformer
120VAC Hot Input
Heat Only Accessory (Line Volt)
120VAC Neutrals
24VAC Hot from Transformer
24VAC Return from Transformer
Flame ense Terminal
2
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Page 19
FIGURE 31
TYPICAL G26 WIRING DIAGRAM
OUTDOOR
UNIT
OUTDOOR
UNIT
B6
COMBU TION
AIR INDUCER
MOTOR
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Page 20
FIGURE 32
GWYCR
SURELIGHT CONTROL
CONTROL
BOX
THERMOSTAT
IGNITION
CONTROL
GAS
VALVE
LIMIT
BLACK
BROWN
TO COMPRESSOR
CONTACTOR
FIELD INSTALLED CLASS II 24V VOLTAGE
FIELD INSTALLED LINE VOLTAGE
TYPICAL G26 FIELD WIRING DIAGRAM L1 N
FUSED DISCONNECT SWITCH
(FURNISHED BY INSTALLER)
TRANSFORMER
DOOR
INTERLOCK
SWITCH
COMBUSTION
AIR INDUCER
COMBUSTION
AIR PROVE
SWITCH
FIELD
MAKE-UP
BOX
GND
J69 WHITE
TO ACCESSORY IF USED.
(ELECTRONIC AIR CLEANER)
IF NOT NEEDED, DO NOT INSTALL
ACCESSORY WIRE IN J69.
GWRY
FLAME
ROLLOUT
SWITCH
Unit Sta t-Up
FOR YOUR AFETY READ BEFORE LIGHTING
WARNING
Do not use this fu nace if any pa t has been unde waĆ
te . Immediately call a qualified se vice technician to
inspect the fu nace and to eplace any pa t of the
cont ol system and any gas cont ol which has been
unde wate .
WARNING
If ove heating occu s, o if gas supply fails to shut
off, shut off the manual gas valve to the appliance beĆ
fo e shutting off elect ical supply.
CAUTION
Befo e attempting to pe fo m any se vice o mainteĆ
nance, tu n the elect ical powe to unit OFF at disĆ
connect switch.
BEFORE OPERATING smell all around the appliance area
for gas. Be sure to smell next to the floor because some gas
is heavier than air and will settle on the floor.
Gas valve may be equipped with either a gas control knob
or lever. Use only your hand to push in or turn the gas conĆ
trol knob or move the gas control lever. Never use tools. If
the knob will not push in or turn or if lever will not move by
hand, do not try to repair it, call a qualified service techniĆ
cian. Force or attempted repair may result in a fire or exploĆ
sion.
G26 units are equipped with a ureLightt ignition sysĆ
tem. Do not attempt to manually light burners on this furĆ
nace. Each time the thermostat calls for heat, the burners
will automatically light. The ignitor does not get hot when
there is no call for heat on units with ureLightt ignition
system.
Gas Valve Ope ation (Figu e 33)
WARNING
If you do not follow these inst uctions exactly, a fi e
o explosion may esult causing p ope ty damage,
pe sonal inju y o death.
1 - STOP! Read the safety information at the beginning of
this section.
2 - et thermostat to lowest setting.
3 - Turn off all electrical power to furnace.
4 - This furnace is equipped with an ignition device
which automatically lights the burner. Do not try to
light the burners by hand.
5 - Remove the unit access panel.
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