Lennox 10GCS Series User manual

08/03
*2P0803*
504,245M
*P504245M*
Page 1
RETAIN THESE INSTRUCTIONS
FOR FUTURE REFERENCE
10GCS
12GCS
E2000 Lennox Industries Inc.
Dallas, Texas, USA
INSTALLATION
INSTRUCTIONS
10GCS & 12GCS
SERIES UNITS
GAS PACKAGED UNITS (2−5 TONS)
Armstrong # 38152A058
504,245M
08/03
Supersedes 05/00
Table of Contents
Unit Dimensions 2. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Parts Arrangement 4. . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Shipping & Packing List 4. . . . . . . . . . . . . . . . . . . . . . . . .
General 4. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Requirements 4. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Clearances 5. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Rigging & Setting Unit 5. . . . . . . . . . . . . . . . . . . . . . . . . . .
Condensate Drain 6. . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Filters 6. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Supply & Return Connections 6. . . . . . . . . . . . . . . . . . . .
Installing Vent Hood 6. . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Combustion Discharge 6. . . . . . . . . . . . . . . . . . . . . . . . . .
Compressors 7. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Gas Piping 7. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
LPG/Propane Units, Tanks, & Piping 8. . . . . . . . . . . . . .
Electrical 8. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Sequence of Operation 11. . . . . . . . . . . . . . . . . . . . . . . . .
Condenser Fan Clearances 12. . . . . . . . . . . . . . . . . . . . .
Start−up Check List 13. . . . . . . . . . . . . . . . . . . . . . . . . . . .
Heating Start−up 13. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Burner Adjustments 14. . . . . . . . . . . . . . . . . . . . . . . . . . . .
Manifold Gas Pressure Adjustment 14. . . . . . . . . . . . . . .
High Altitude Information 14. . . . . . . . . . . . . . . . . . . . . . .
Unit Controls 14. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Maintenance 15. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Troubleshooting 15. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Led Codes & Flash Rates 16. . . . . . . . . . . . . . . . . . . . . . .
Repair Parts & Accessories 16. . . . . . . . . . . . . . . . . . . . .
WHAT TO DO IF YOU SMELL GAS:
If the information in this manual is not
followed exactly, a fire or explosion
may result causing property damage,
personal injury or loss of life.
WARNING
Do not store or use gasoline or other
flammable vapors and liquids in the
vicinity of this or any other ap
pliance.
Installation and service must be
performed by a qualified installer,
service agency or the gas supplier.
DDo not try to light any appliance.
DDo not touch any electrical switch; do not
use any phone in your building.
DImmediately call your gas supplier from a
neighbor’s phone. Follow the gas supplier’s
instructions.
DIf you cannot reach your gas supplier, call
the fire department.
DExtinguish any open flames.
Litho U.S.A.
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Page 2
10GCS Unit Dimensions − inches (mm)
Corner Weights  lbs. (kg)
M
ode
lAA BB CC DD
Model
Number lbs. kg lbs. kg lbs. kg lbs. kg
10GCS−024 75 34 67 30 68 31 91 41
10GCS−030 77 35 69 31 70 32 95 43
10GCS−036 84 38 76 34 77 35 103 47
10GCS−042 92 42 83 38 83 38 112 51
10GCS−048 112 51 101 46 101 46 136 62
10GCS−060 116 53 106 48 106 48 142 64
Center of Gravity  inches (mm)
Model EE FF
Model
Number inch mm inch mm
10GCS−024 211/2 546 25 635
10GCS−030 211/2 546 25 635
10GCS−036 211/2 546 25 635
10GCS−042 211/2 546 25 635
10GCS−048 233/8 594 301/8 511
10GCS−060 233/8 594 301/8 511
FRONT VIEW
TOP VIEW TOP VIEW BASE SECTION
BACK VIEW
LEFT SIDE
CONDENSER
COIL
INTAKE
AIR
CONDENSATE
DRAIN
FLUE
OUTLET
COMPRESSOR
DOWNFLOW
SUPPLY AIR
OPENING
CONDENSER COIL
EXHAUST AIR
CONDENSER
COIL FAN
DOWNFLOW
RETURN AIR
OPENING
HORIZONTAL
SUPPLY AIR
OPENING
HORIZONTAL
RETURN AIR
OPENING
AA
D
BB
CC
DD
CONDENSER COIL
INTAKE AIR
CONDENSER
COIL
CONDENSER COIL
EXHAUST AIR
A
C
BB
RIGHT SIDE
ELECTRICAL
INLETS
GAS
INLET
COMBUSTION AIR
INDUCER
BLOWER
C
HORIZONTAL
RETURN AIR
OPENING
(048/060)
A
PE
F
G
H
G
2 (51)
J
FF
EE
FILTER
RACK
BASE RAIL
47/8
(124)
27/16
(62)
45/8
(117)
CENTER
OF
GRAVITY
M
MM
M
L
LL
L
E
K
Q
FORKLIFT
SLOTS
(Front and
Back Only)
BASE RAIL
BASE RAIL
R
N
BASE RAIL
BASE RAIL
EVAPORATOR
COIL
BLOWER
HEAT
EXCHANGER
REFRIGERANT
SERVICE
PORTS
M
ode
lA B C D E F G H
Model
Number inch mm inch mm inch mm inch mm inch mm inch mm inch mm inch mm
10GCS−024, 30, 36 2711/16 703 455/8 1159 455/8 1159 251/4 641 113/16 46 4 102 17/8 48 1715/16 456
10GCS−042 3111/16 805 455/8 1159 455/8 1159 291/4 743 113/16 46 4 102 17/8 48 1915/16 506
10GCS−048, 060 3311/16 856 5411/16 1389 495/8 1260 317/16 799 11/8 29 61/8 159 21/4 57 1915/16 506
Model
J K L M N P Q R
M
o
d
e
l
Number inch mm inch mm inch mm inch mm inch mm inch mm inch mm inch mm
10GCS−024, 30, 36 21/4 57 155/8 397 11−1/2 292 17−1/2 445 5 127 4 102 463/8 1179 463/8 1179
10GCS−042 21/4 57 155/8 397 11−1/2 292 17−1/2 445 5 127 4 102 463/8 1179 463/8 1179
10GCS−048, 60 31/2 89 171/8 435 12 305 21−1/2 527 41/8 105 55/8 143 551/4 1403 501/2 1283
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Page 3
12GCS Unit Dimensions − inches (mm)
Corner Weights  lbs. (kg)
Model AA BB CC DD
Model
Number lbs. kg lbs. kg lbs. kg lbs. kg
12GCS024 80 36 69 31 73 33 99 45
12GCS030 82 37 71 32 75 34 103 47
12GCS036 89 40 78 35 82 37 111 50
12GCS042 97 44 89 40 88 40 130 59
12GCS−048, −060 117 53 103 47 106 48 144 65
Center of Gravity  inches (mm)
Model EE FF
Model
Number inch mm inch mm
12GCS024 21 533 251/2 648
12GCS030 21 533 251/2 648
12GCS036 21 533 251/2 648
12GCS042 21 533 251/2 648
12GCS048, −060 223/4 578 301/2 775
FRONT VIEW
TOP VIEW TOP VIEW BASE SECTION
BACK VIEW
LEFT SIDE
CONDENSER
COIL
INTAKE
AIR
CONDENSATE
DRAIN
FLUE
OUTLET
COMPRESSOR
DOWNFLOW
SUPPLY AIR
OPENING
CONDENSER COIL
EXHAUST AIR
CONDENSER
COIL FAN
DOWNFLOW
RETURN AIR
OPENING
HORIZONTAL
SUPPLY AIR
OPENING
HORIZONTAL
RETURN AIR
OPENING
AA
D
BB
CC
DD
CONDENSER COIL
INTAKE AIR
CONDENSER
COIL
CONDENSER COIL
EXHAUST AIR
A
C
B
B
RIGHT SIDE
ELECTRICAL
INLETS
GAS
INLET
COMBUSTION AIR
INDUCER
BLOWER
C
HORIZONTAL
RETURN AIR
OPENING
(048/060)
A
PE
F
G
H
G
2 (51)
J
FF
EE
FILTER
RACK
BASE RAIL
47/8
(124)
27/16
(62)
45/8
(117)
CENTER
OF
GRAVITY
M
MM
M
L
LL
L
E
K
Q
FORKLIFT
SLOTS
(Front and
Back Only)
BASE RAIL
BASE RAIL
R
N
BASE RAIL
BASE RAIL
EVAPORATOR
COIL
BLOWER
HEAT
EXCHANGER
REFRIGERANT
SERVICE
PORTS
M
ode
lA B C D E F G H
Model
Number inch mm inch mm inch mm inch mm inch mm inch mm inch mm inch mm
12GCS024, 30, 36 2711/16 703 455/8 1159 455/8 1159 251/4 641 113/16 46 4 102 17/8 48 1715/16 456
12GCS042 3111/16 805 455/8 1159 455/8 1159 291/4 743 113/16 46 4 102 17/8 48 1915/16 506
12GCS048, 060 3311/16 856 5411/16 1389 495/8 1260 317/16 799 11/8 29 61/8 159 21/4 57 1915/16 506
Model
J K L M N P Q R
M
o
d
e
l
Number inch mm inch mm inch mm inch mm inch mm inch mm inch mm inch mm
12GCS024, 30, 36 21/4 57 155/8 397 11−1/2 292 17−1/2 445 5 127 4 102 463/8 1179 463/8 1179
12GCS042 21/4 57 155/8 397 11−1/2 292 17−1/2 445 5 127 4 102 463/8 1179 463/8 1179
12GCS048, 060 31/2 89 171/8 435 12 305 21−1/2 527 41/8 105 55/8 143 551/4 1403 501/2 1283
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Page 4
Parts Arrangement
condenser coil
BLOWER
compressor
condenser fan
combustion
air inducer
gas valve
gas
manifold burner box
heat exchanger
assembly
blower motor
control box section
pressure switch
Figure 1
Shipping & Packing List
1 − Assembled gas package unit
1 − Vent hood assembly with screen and screws
As soon as the unit is received, it should be inspected for
possible damage during transit. If damage is evident, the
extent of the damage should be noted on the carrier’s
freight bill. A separate request for inspection by the carrier’s
agent should be made in writing.
General
These installation instructions are intended as a general
guide only, for use by an experienced, qualified contractor.
The 10GCS and 12CGS units are single−package air
conditioners with gas heat designed for outdoor installation
on a rooftop or a slab.
The units are completely assembled. All piping, refrigerant
charge, and electrical wiring are factory installed and
tested. The units require only electric power, gas piping,
condensate drain and duct connections plus assembly of
heating rain hood at the point of installation.
Requirements
NOTE − These units must not be used as a construction
heater at any time during any phase of construction.
Very low return air temperatures, harmful vapors, and
misplacement of the filters will damage the unit and its
efficiency.
WARNING
Improper installation, adjustment, alteration, service
or maintenance can cause property damage, personal
injury or loss of life. Installation and service must be
performed by a qualified installer or service agency.
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Page 5
WARNING
Product contains fiberglass wool.
Disturbing the insulation in this product during
installation, maintenance, or repair will expose you
to fiberglass wool dust. Breathing this may cause
lung cancer. (Fiberglass wool is known to the State
of California to cause cancer.)
Fiberglass wool may also cause respiratory, skin,
and eye irritation.
To reduce exposure to this substance or for further
information, consult material safety data sheets
available from address shown below, or contact your
supervisor.
Lennox Industries Inc.
P.O. Box 799900
Dallas, TX 75379−9900
These units are design certified by E.T.L. and E.T.L.
Canada as follows:
1 − For use as a forced air furnace with cooling unit.
2 − For outdoor installation only.
3 − For installation on combustible material.
4 − For use with natural gas or propane gas.
Not suitable for use with conventional venting systems
These units must be installed in accordance with the
following national and local safety codes.
1 − National Electrical Code ANSI/NFPA No. 70 latest edi
tion (U.S.A.).
2 − Local gas utility requirements. In the absence of local
gas codes the National Fuel Gas Code ANSI Z223.1
latest edition should be used. (U.S.A.)
3 − Canadian Electrical Code C22.1 Part 1 (latest edition).
4 − Canadian Installation Codes CAN/CGA−B149.1 & .2
(latest edition).
If components are to be added to a unit to meet local codes,
they are to be installed at the dealer’s and/or customer’s
expense.
Clearances
All units require certain clearances for proper operation
and service. Refer to figure 2 for the clearances required
for combustible construction, servicing, and proper unit
operation.
When installed at ground level, this unit must be used with
the 4−inch lift kit or other applicable means to raise the
bottom of the flue hood to 12 inches above ground to meet
the snow requirements. See Combustion Discharge
section. Clearance to combustibles below unit is 10 inches
since the flue points down.
NOTE − Do not permit overhanging structures or shrubs to
obstruct condenser air discharge outlet, combustion air in
let or vent outlet.
ÉÉ
ÉÉ
ÉÉ
ÉÉ
ÉÉ
ÉÉ
ÉÉÉÉÉÉÉÉ
ÉÉÉÉÉÉÉÉ
ÉÉÉÉÉÉÉÉ
ÉÉÉÉÉÉÉÉ
ÉÉÉÉÉÉÉÉ
Figure 2
ÉÉÉÉÉÉÉÉ
ÉÉÉÉÉÉÉÉ
ÉÉÉÉÉÉÉÉ
ÉÉÉÉÉÉÉÉ
12 in.
24 in.
36 in.*
Service Clearances for Units
Top Clearance Unobstructed
Bottom Clearance Is 10 In.
RETURN SUPPLY
front
rear
left
*Rear clearance is 36 in. with or 2 in. without an economizer.
ÉÉÉ
ÉÉÉ
ÉÉÉ
ÉÉÉ
ÉÉÉ
ÉÉÉ
12 in.
right
In the U.S. units may be installed on combustible floors
made from wood or class A, B, or C roof covering material.
In Canada, units may be installed on combustible floors.
Units must be installed outdoors. Overhanging structures
or shrubs should not obstruct condenser air discharge
outlet.
Use the following guidelines to select a suitable location for
these units.
Rigging & Setting Unit
Exercise care when moving the unit. Do not remove any
packaging until the unit is near the place of installation. A
sling assembly may be used to lift unit. Spreaders whose
length exceeds the largest dimension across the unit
MUST be used across the top of the unit.
CAUTION
Before lifting a unit, make sure that the weight is dis
tributed equally on the cables so that it will lift evenly.
Units may also be moved or lifted with a forklift while still in
the factory supplied packaging.
NOTE − Length of forks must be a minimum of 42 inches.
1 − Unit is designed for outdoor installation only. Unit must
be installed so all electrical components are protected
from water.
2 − Condenser coils must have an unlimited supply of air.
3 − For ground level installation, use a level pre−fabricated
pad or use a level concrete slab with a minimum thick
ness of 4 inches. The length and width should be at
least 6 inches greater than the unit base. Do not tie the
slab to the building foundation.
4 − Maintain level within a tolerance of 1/4 inch maximum
across the entire length or width of the unit.
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Page 6
Condensate Drain
The packaged unit is equipped with a 3/4 inch fpt coupling
for condensate line connection. Plumbing must conform to
local codes. Use a sealing compound on male pipe
threads.
The drain line must be properly trapped and routed to a
suitable drain. See figure 3 for proper drain arrangement.
The drain line must pitch to an open drain or pump a
minimum of 1 inch per 10 feet to prevent clogging of the
line. Seal around drain connection with suitable material to
prevent air leakage into return air system.
Drain piping should not be smaller than drain connection at
coil. An open vent in drain line will some times be required
due to line length, friction and static pressure. Drains
should be constructed in a manner to facilitate future clean
ing.
NOTE − The condensate drain line MUST be trapped to
provide proper drainage.
Á
Á
Á
Á
Á
Á
Á
Á
Á
Á
Á
unit
Minimum Pitch
1 in. (25 mm) per
10’ (3 m) of line
mounting
frame
Figure 3
open
vent
Trap must be deep enough to offset maximum
static difference (Generally, 3 inches minimum).
Typical Condensate Drain
Filters
No filters are supplied with the unit. Filters must always be
installed ahead of evaporator coil and must be kept clean or
replaced. Dirty filters will reduce the airflow of the unit.
Filters sizes are shown in table 1.
Unit is equipped with an internal filter clip which is located in
indoor coil compartment attached to side of the unit drain
pan.
Table 1
Unit Filter Size
Unit Model Filter Size
−024, −030, −036 24 in. X 25 in.
−042 28 in. X 25 in.
−048 −060 30 in. X 30 in.
Supply & Return Connections
Duct system should be designed and sized according to
the methods in Manual Q of the Air Conditioning
Contractors of America (ACCA).
A closed return duct system shall be used. This shall not
preclude use of economizers or outdoor fresh air intake. It
is recommended that supply and return duct connections
at the unit be made with flexible joints.
The supply and return air duct systems should be designed
for the CFM and static requirements of the job. They
should NOT be sized to match the dimensions of the
duct connections on the unit.
CAUTION
When fastening duct system to side duct flanges on
unit, insert screws through duct flanges only. Do not
insert screws through casing. Outdoor duct must be
insulated and waterproofed.
Installing Vent Hood
The vent hood is installed by placing screen in hood and
securing with four #8 x 3/8 large blunt sheet metal screws
and four #8 flat speed nuts as shown in figure 4. Place hood
with screen in position and attach with three #8 x 1/2 sheet
metal screws using holes provided.
Vent Hood Installation
Figure 4
HOOD
screen
Combustion Discharge
The products of combustion are discharged horizontally
through a screened opening on the gas heat side panel.
The horizontal vent system shall terminate at least 4 feet
below, 4 feet horizontally from, or 1 foot above any door,
window, or gravity air inlet into the building. The vent
system shall terminate at least 3 feet above any forced air
inlet located within 10 feet. The bottom of the vent
terminal shall be located at least 12 inches above grade.
Minimum horizontal clearance of 4 feet from electric
meters, gas meters, regulators, and relief equipment is
required.
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Page 7
The vent outlet must be installed in a location that prevents
building degradation and must be consistent with the
National Fuel Gas Code, Z223.1 or CAN/CGA−B149.1 & .2.
In addition to the above requirements, consideration must
be given to prevent unwanted ice buildup from the vent
condensate. The vent should not be located on the side of a
building where the prevailing winter winds could trap the
moisture causing it to freeze on the walls or on overhangs
(under eaves). The vent location should not discharge over
a sidewalk, patio or other walkway, where the condensate
could cause the surface to become slippery.
The products of combustion must not be allowed to
accumulate within a confined space and recirculate.
Compressors
Units are shipped with the compressor mountings
factory−adjusted and ready for operation.
CAUTION
Do not loosen compressor mounting bolts.
Gas Piping
Proper sizing of gas piping depends on the cubic feet per
hour of gas flow required, specific gravity of the gas and
length of run. The current National Fuel Gas Code Z223.1
should be followed in all cases unless superseded by local
codes or gas company requirements. Refer to tables 2 and
3. In Canada see CAN/CGA B.149.1 & .2 (latest edition).
Table 2
Gas Heat Application Data
Input Rating
(Btu)
Output Rating
(Btu)
Gas Capacity
(FT3/ HR)
50,000 40,000 47
75,000 60,000 70
100,000 80,000 93
125,000 100,000 116
Before connecting piping, check with gas company or
authorities having jurisdiction for local codes or require
ments. When installing gas supply piping, length of run
from gas meter must be considered in determining pipe
size for 0.5 inch w.c. maximum pressure drop. Do not
use supply pipe smaller than unit gas connection. For
natural gas unit, operating pressure at the unit gas con
nection must be a minimum of 4.5 inch w.c. and a maxi
mum of 13.5 w.c. For propane/LP gas units, operating
pressure at the unit gas connection must be a minimum
of 11 inches w.c. and a maximum of 13.5 inches w.c.
Table 3
Gas Pipe Capacity−FT3/ HR
Length in Feet
Nominal Iron Pipe Size (inches)
L
engt
h
i
n
F
eet 1/2 in. 3/4 in. 1 in. 1−1/4 in.
10 132 278 520 1050
20 92 190 350 730
30 73 152 285 590
40 63 130 245 500
50 56 115 215 440
60 50 105 195 400
70 46 96 180 370
80 43 90 170 350
90 40 84 160 320
100 38 79 150 305
When making piping connections, a drip leg should be
installed on vertical runs to serve as a trap for sediment or
condensate. A 1/8 inch N.P.T. tap accessible for test gauge
connection must be provided in field piping upstream from
gas supply connection to unit. Install a ground joint union
between gas control manifold and the manual main shut−
off valve. See figure 5.
Compounds used on threaded joints of gas piping shall be
resistant to the action of propane/LP gases.
Figure 5
base of unit
ground joint
union
field provided
1/8 in. pressure tap
manual main
shut−off valve
drip
leg
gas piping
support
unit
support
Drip Leg Installation
Pressure Test Gas Piping
When pressure testing gas lines, the gas valve must be dis
connected and isolated. Gas valve can be damaged if sub
jected to more than 0.5 psig (14 inch w.c.). See figure 6.
If test pressure is equal to or less than 0.5 psig (14 inch
w.c.) shutoff the manual main shutoff valve before pres
sure testing to isolate unit from gas supply system.
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Page 8
gas valve cap
Manual Main Shut−off Valve Will Not Hold Test
Pressures in Excess of 0.5 PSIG (14 in. w.c.)
Fi
g
ure 6
unit
Isolate Gas Valve To Pressure Test
NOTE − Codes may require that manual main shut off valve
and union (furnished by installer) be installed in gas line exter
nal to unit. Union must be of the ground joint type.
Danger of explosion. Can cause injury or
product or property damage. Do not use
matches, candles, flame or other sources
of ignition to check for leaks.
WARNING
!
After gas piping is complete, carefully check all piping con
nections (factory and field) for gas leaks. Use soap solution
or other preferred means.
NOTE − In case of emergency shutdown, shut off main
manual gas valve and disconnect main power to unit.
These devices should be properly labeled by installer.
The heating value of the gas may differ with locality. The
value should be checked with the local gas utility.
NOTE − Units are shipped equipped for natural gas, but can
be converted to LPG/propane with a conversion kit.
NOTE − There may be a local gas utility requirement speci
fying a minimum diameter for gas piping. All units require a
1/2 inch pipe connection at the gas valve.
Gas piping recommendations:
1 − A drip leg and a ground joint union must be installed in
the gas piping.
A ground joint union is recommended by the man
ifold/valve.
2 − When required by local codes, a manual shutoff valve
may have to be installed outside of the unit.
3 − Use pipe thread sealing compound resistant to pro
pane gas sparingly on male threads.
4 − The gas supply should be a separate line and installed
in accordance with all safety codes. After the gas con
nections have been completed, open the main shutoff
valve admitting normal gas pressure to the mains.
Check all joints for leaks with soap solution or other
material suitable for the purpose.
CAUTION
Some soaps used for leak detection are corrosive to
certain metals. Carefully rinse piping thoroughly af
ter leak test has been completed. Do not use
matches, candles, flame or other sources of ignition
to check for gas leaks.
5 − The furnace and its individual manual shutoff valve
must be disconnected from the gas supply piping sys
tem during any pressure testing of that system at test
pressures in excess of 1/2 PSIG (3.48kPa).
IMPORTANT
The furnace must be isolated from the gas supply
piping system by closing its individual manual shut−
off valve during any pressure testing of the gas sup
ply piping system at test pressures equal to or less
than 1/2 psig. See figure 6.
The furnace and its individual shut−off valve must be
disconnected from the gas supply piping system
during any pressure testing of the system at test
pressures greater than 1/2 psig.
6 − A 1/8 inch N.P.T. plugged tapping, accessible for test
gage connections, must be installed immediately up
stream of the gas supply connection to the furnace.
LPG/Propane Units, Tanks, & Piping
Check the unit rating plate for type of gas that unit is
equipped for. If conversion is required use the approved
conversion kit. The unit may be converted in the field for
use with LPG/propane gas with accessory kit by an
approved licensed pipe fitter or technician.
All LPG/propane gas equipment must conform to the safety
standards of the National Fire Protection Association.
For satisfactory operation, LPG/propane gas pressure must
be a minimum of 11 inches W.C. at the unit under full load.
Complete information regarding tank sizing for
vaporization, recommended regulator settings, and pipe
sizing is available from most regulator manufacturers and
LPG/propane gas suppliers.
Check all connection for leaks when piping is completed,
using a soapy solution.
Electrical
ALL WIRING SHOULD BE DONE IN ACCORDANCE
WITH NATIONAL ELECTRIC CODE, ANSI/NFPA No. 70
(LATEST EDITION), IN CANADA CSA C22.2 Part 1
(LATEST EDITION), OR WITH LOCAL CODES, WHERE
THEY PREVAIL.
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Figure 7
10GCS Series Gas Packaged Units
Typical Wiring Diagram
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Figure 8
12GCS Series Gas Packaged Units
Typical Wiring Diagram
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Use wiring with a temperature limitation of 75_C min.; run
the 208 or 230 volt, 60 hertz electric power supply through a
fused disconnect switch to control box of unit and connect
as shown in the wiring diagram located on the inside of the
control access panel.
Unit must be electrically grounded in accordance with local
codes or in the absence of local codes with the National
Electric Code, ANSI/NFPA No. 70 (latest edition) or CSA
C22.2 Part 1 (latest edition).
Power supply to the unit must be N.E.C. Class 1, and must
comply with all applicable codes. A fused disconnect
switch should be field provided for the unit. The switch must
be separate from all other circuits. If any of the wire
supplied with the unit must be replaced, replacement wire
must be of the type shown on the wiring diagram.
Electrical wiring must be sized to carry minimum circuit
ampacity marked on the unit. USE COPPER
CONDUCTORS ONLY. Each unit must be wired with a
separate branch circuit and be properly fused.
CAUTION
When connecting electrical power and control wir
ing to the unit, waterproof type connectors MUST be
used so that water or moisture cannot be drawn into
the unit during normal operation.
See figure 9 for field connection of line voltage wiring. See
figure 7 for typical wiring diagram.
208/230 Line Voltage Wiring
NOTE − If 208 voltage is supplied, transformer
connections must be made.
L1
ground
lug
L2
Figure 9
contactor
fused disconnect switch
(furnished by installer)
Thermostat
The room thermostat should be located on an inside wall
where it will not be subject to drafts, sun exposure or heat
from electrical fixtures or appliances. Follow
manufacturer’s instructions enclosed with thermostat for
general installation procedure. Color coded insulated wires
(# 18 AWG) should be used to connect thermostat to unit.
Four wires are required for cooling.
Heat Anticipator Setting
It is important that the anticipator setpoint be correct. Too
high of a setting will result in longer heat cycles and a
greater temperature swing in the conditioned space.
Reducing the value below the correct setpoint will give
shorter ON" cycles and may result in the lowering of the
temperature within the conditioned space. Heat
Anticipator Settings: 0.75 AMP
Sequence of Operation
Cooling System
The cooling section is a complete factory package utilizing
an air−cooled condenser. The system is factory−charged
with HCFC−22. The compressor is hermetically sealed,
internally sprung and base mounted with rubber−insolated
hold−down bolts.
Unit compressors have internal protection. In the event
there is an abnormal rise in temperature of the compressor,
the protector will open and cause the compressor to stop.
After the initial installation, the compressor should be
given three false starts (energized just long enough to
make a few revolutions), with 5−7 minutes between
each start, before being put into full time service.
Cooling Sequence of Operation
When the thermostat calls for cooling, R" is closed to G"
and Y" (wiring schematic) which completes the low voltage
control circuit, energizing the compressor, condenser fan
motor and blower motor.
NOTE − At the start of the each cooling demand, the
combustion air blower (draft motor) will operate for 10
seconds.
Blower Delays − Cooling
Blower is controlled by a timing relay delaying blower on 5
seconds and blower off 90 seconds. This feature is
intended to deter insect nesting.
System Performance
For maximum performance of this cooling system, the
operating temperatures and pressure should be checked
and superheat determined at Standard ARI test conditions
of 82_F outdoor temperature minus ( − ) 80_F indoor dry
bulb / 67_F indoor wet bulb. If superheat measured
deviates from values in table 4 below, refrigerant charge
should be adjusted accordingly for maximum performance.
Table 4
Suction Superheat Values
Unit Model No.
Suction Superheat
82_F OD minus 80_F IDDB
/ 67_F IDWB
10GCS−024 18 − 20_
10GCS−030, −036 17 − 19_
10GCS−042 18 − 20_
10GCS−048, −060 16 − 18_
12GCS−024, −030 18 − 20_
12GCS−036, −042 13 − 15_
12GCS−048, −060 14 − 16_
NOTE − With the proper thermostat and subbase, continu
ous blower operation is possible by closing the R to G cir
cuit. Cooling blower delay is also functional in this mode.
Verify system performance using table 5 as a general guide.
Table should not be used for charging unit. Minor variations
in these pressures may be expected due to differences in
installations. Significant differences could mean that the
system is not properly charged or that a problem exists with
some component in the system.
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Table 5
Normal Operating Pressures
80°F db / 87°F wb RETURN AIR Air Temperature Entering Outdoor Coil (°F)
Model Pressure 65°70°75°80°82°85°90°95°100°105°110°115°
10GCS−024 72 75 79 81 82 83 85 87 88 89 91 92
10GCS−030 67 70 73 75 77 78 81 83 84 84 85 85
10GCS−036
Suction
72 75 77 80 81 82 84 86 88 89 91 92
10GCS−042 Suction 72 75 78 82 83 84 86 88 89 90 92 93
10GCS−048 75 79 80 81 83 84 85 86 87 88 89 90
10GCS−060 79 79 80 81 81 82 83 84 85 86 87 88
10GCS−024 171 185 199 213 219 229 244 260 267 275 301 327
10GCS−030 186 192 198 215 221 231 247 263 282 300 312 323
10GCS−036
Liquid
175 191 207 224 230 239 255 271 288 305 320 335
10GCS−042 Liquid 181 197 213 229 235 245 261 277 294 310 328 345
10GCS−048 172 184 197 212 220 235 251 262 279 297 321 335
10GCS−060 192 205 222 236 249 263 277 293 313 331 348 360
12GCS−024 75 77 80 82 83 84 87 88 90 90 91 92
12GCS−030 67 70 73 76 80 78 82 85 86 86 87 88
12GCS−036
Suction
73 75 78 80 82 82 85 87 88 89 91 92
12GCS−042 Suction 77 78 80 81 81 82 84 85 87 88 89 90
12GCS−048 71 74 75 79 81 81 84 88 87 87 88 89
12GCS−060 74 77 80 81 82 84 85 88 96 96 87 88
12GCS−024 149 164 178 193 195 208 222 237 254 271 289 306
12GCS−030 145 161 178 192 195 207 223 238 254 270 288 305
12GCS−036
Liquid
156 172 187 203 207 219 234 260 267 284 303 322
12GCS−042 Liquid 159 175 190 208 209 222 237 253 270 298 306 326
12GCS−048 152 168 185 198 209 215 230 246 254 281 298 316
12GCS−060 155 190 205 211 215 230 244 269 276 293 311 332
Used carefully, this table could serve as a useful service
guide. Data is based on 80°F dry bulb / 87°F wet bulb return
air. Allow unit operation to stabilize before taking pressure
readings.
Heating System − Sequence of Operation
When thermostat is calling for heat the draft motor is
energized by the 24 volt relay in the blower ignition control
which closes the 240V contact to the draft motor. When the
speed of the draft motor reaches the proper rpm the
pressure switch closes to power the ignition control.
When PSW on blower/ignition control is energized, a
pre−purge time is initiated (30 seconds nominal). When
pre−purge has expired the main gas valve is energized for
direct ignition. The blower/ignition control will energize the
main gas valve and spark electrode/flame sensor for a
period of 10 seconds. The blower/ignition control will spark
for the full 10 seconds regardless of establishing flame and
then look for a signal from the electrode/flame sensor that a
flame has been established. Forty−five (45) seconds
nominal after the initial trial for ignition, the circulating air
blower will start. If the electrode/flame sensor does not
sense that a flame has been established in the 10 second
interval, then the blower/ignition control will open the 24
volt contacts to the main gas valve. The blower/ignition
control is designed to repeat this trial for ignition a total of
three times. If, at the end of the third trial, a flame still has
not been established, then the blower/ignition control will
try to light again one hour later. The one hour retry is
indefinite. The blower/ignition control can be reset by
interrupting the unit power or the thermostat circuit. When
the thermostat is satisfied the draft motor gas valve is
de−energized. The blower motor will continue to run for 120
seconds after the furnace is shut down.
Condenser Fan Clearances
Figure 10 illustrates the critical measurements of the out
door fan system. This dimension should be checked and
fan adjusted accordingly anytime servicing of the outdoor
fan system is required.
Condenser Fan Clearances
Figure 10
A
Unit Model No. A
−024
−030,−036,−042,−048,−060 3−1/2 in.
3 in.
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Start−Up Check List
Complete the following checks before starting the unit.
1 − Check the type of gas being supplied. Be sure it is the
same as listed on the unit nameplate.
2 − Make sure that the vent hood has been properly installed.
Heating Start−Up
FOR YOUR SAFETY READ BEFORE LIGHTING
BEFORE LIGHTING 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.
Electric shock hazard. Can cause injury
or death. Do not use this unit if any part
has been under water. Immediately call a
qualified service technician to inspect
the unit and to replace any part of the con
trol system and any gas control which
has been under water.
WARNING
!
Danger of explosion. Can cause injury or
product or property damage. If overheating
occurs or if gas supply fails to shut off, shut
off the manual gas valve to the appliance
before shutting off electrical supply.
WARNING
!
WARNING
Danger of explosion and fire. Can cause
injury or product or property damage. You
must follow these instructions exactly.
!
Electric shock hazard. Can cause injury or
death. Before attempting to perform any
service or maintenance, turn the electrical
power to unit OFF at disconnect switch(es).
Unit may have multiple power supplies.
WARNING
!
Use only your hand to push in or turn the gas control knob.
Never use tools. If the knob will not push in or turn by hand,
do not try to repair it, call a qualified service technician.
Force or attempted repair may result in a fire or explosion.
This furnace is equipped with a direct ignition control. Do
not attempt to manually light the burners.
1 − Turn off electrical power to unit.
2 − Set thermostat to lowest setting.
3 − Turn gas valve knob or push gas valve lever to ON
position. Refer to figures 11 and 12.
4 − Turn on electrical power to unit.
5 − Set room thermostat to desired temperature. (If ther
mostat setpoint temperature is above room tempera
ture after the pre−purge time expires, main burners will
light).
ON
OFF
Figure 11
Honeywell VR8205 Series Gas Valve
Gas Valve Shown In Off Position
Figure 12
Robertshaw 7200 Gas Valve
gas valve
selector arm
in off position
To Shut Down:
1 − Turn off electric power to unit.
2 − Depress and turn knob or pull lever to OFF position.
Post Start−up Check List (Gas)
After the entire control circuit has been energized and the
heating section is operating, make the following checks:
1 − Check for gas leaks using soap solution in the unit pip
ing as well as the supply piping.
2 − Check for correct manifold gas pressures. See Man
ifold Gas Pressure Adjustment."
3 − Check the supply gas pressure. It must be within the
limits shown on rating nameplate. Supply pressure
should be checked with all gas appliances in the build
ing at full fire. At no time should the standby gas pres
sure exceed 13 inches W.C., nor the operating pres
sure drop below 5.0 inches W.C. for natural gas units,
11 inches W.C. for propane gas. If gas pressure is out
side these limits, contact your gas supplier for correc
tive action.
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4 − Adjust temperature rise to the range specified on the
rating plate.
Burner Adjustments
To check or change burners or orifices, CLOSE MAIN
MANUAL SHUTOFF VALVE AND SHUT OFF ALL
POWER TO THE UNIT.
1 − Open the union fitting in the gas supply line just up
stream of the unit gas valve and downstream from the
manual shutoff valve.
2 − Remove Burner Access Panel.
3 − Remove the four (4) screws, two (2) on the side and
two (2) on bottom that mount the burner rack assembly
to the burner plate.
4 − Disconnect wiring to the gas valve and the elec
trode/flame sensor. Remove burner rack assembly
from the unit by pulling back. Burners are now ac
cessible to service.
5 − Reverse the above procedure to replace the assem
bly. Make sure that burners are level and centered into
each burner’s corresponding heat exchanger tube.
Manifold Gas Pressure Adjustment
For Natural Gas Applications
The minimum permissible gas supply pressure is 5.0
inches W.C. for purpose of input adjustment.
Gas input must never exceed the input capacity shown on
the rating plate. The furnace is equipped for rated inputs
with manifold pressures as follows:
Natural Gas 3.5 inches W.C.
The manifold pressure can be measured by removing the
pipe plug in the downstream side of the gas valve and
connecting water manometer or gauge.
In no case should the final manifold pressure vary more
than 0.3 inch W.C. from the above specified pressures.
See figures 11 and 12. To adjust the regulator, turn the
adjusting screw on the regulator, turn the adjusting screw
on the regulator clockwise to increase pressure and input;
counterclockwise to decrease pressure and input.
Check the furnace rate by observing gas meter, making
sure all other gas appliances are turned off. The test hand
on the meter should be timed for at least one revolution.
Note the number of seconds for one revolution.
BTU/HR = Cubic Feet Per Revolution X 3600 X Heating Value
INPUT No. Seconds Per Revolution
The heating value of your gas can be obtained from your
local utility.
Example: By actual measurement, it takes 38 seconds for
the hand on the 1−cubic foot dial to make a revolution with a
100,000 Btuh furnace running. The result is 99,750 Btuh,
which is close to the 100,000 Btuh rating of the furnace.
For LPG / Propane Gas Applications
L.P.G./Propane units require a regulator, and a regulator on
the L.P.G./Propane tank is also required.
The minimum permissible gas supply pressure is 11 inches
W.C. for purpose of input adjustment.
If at any time ignition is slow and burner does not seem to
be operating correctly, check manifold pressure. It should
be 10.0 inches to 10.5 inches W.C. PRESSURE FOR
LPG/PROPANE.
Furnace is designed to obtain rated input at 10.0 inches
W.C. To check this pressure:
1 − Turn off gas valve.
2 − Remove plug on valve marked OUTLET PRES
SURE"
3 − Install water manometer.
Turn gas valve ON. If manifold pressure must be adjusted,
remove cap from pressure regulator and turn adjustment
screws clockwise to increase pressure, counterclockwise
to reduce pressure. After checking pressure, turn gas off,
remove manometer fitting and replace pipe plug and
regulator cap. Put furnace in operation and leak check plug
for leaks using soapy solution.
High Altitude Information
Ratings shown on the rating plate for elevations up to 4,500
feet. For elevations above 4,500 feet, ratings should be
reduced at a rate of four (4) percent for each 1,000 feet
above sea level. See National Fuel Gas Code Z223.1
(latest edition) or the requirements of the
CAN/CGA−B149.1 or B149.2 Installation Code.
Unit Controls
Limit Control
This control is located inside the heating compartment and
is designed to open at abnormally high air temperatures. It
resets automatically. The limit switch operates when a high
temperature condition, caused by inadequate blower
supply airflow, occurs, thus shutting down the
blower/ignition control and closing the main gas valve. The
circulating air blower will continue to operate.
Pressure Switch
If the draft motor should fail, the pressure switch prevents the
blower/ignition control and gas valve from being energized.
Spark Electrode and Flame Sensor Rod
The spark electrode and flame sensor rod are part of the
burner assembly. The burner position of the spark
electrode varies by model. The flame sensor rod is always
adjacent to the spark electrode. If the blower/ignition
control does not receive a signal from the flame sensor
indicating that the burners have established flame, the
main gas valve will close after the 10 second ignition trial
period built into the ignition control.
Rollout Switch
The switch is located above the main burners which in the
event of a sustained main burner rollout shuts off the
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blower/ignition control and closes the main gas valve. To
reset, push the button on top of the switch.
Auxiliary Limit
This control is located in the side of the circulating air blower
housing. The switch will open and shut off the blower/ignition
control and close the main gas valve should the circulating
blower fail to operate. This control resets automatically.
Maintenance
Normal Maintenance
Periodic inspection and maintenance normally consists of
changing or cleaning filters and (under some conditions)
cleaning the main burners.
Filters
Not supplied. Inspect once a month. Replace disposable or
clean permanent type as necessary. DO NOT replace per
manent type with disposable.
Motors
Indoor, outdoor fan and vent motors are permanently
lubricated and require no maintenance.
Outdoor Coil
Dirt and debris should not be allowed to accumulate on the
outdoor coil surface or other parts in the air circuit. Cleaning
should be as often as necessary to keep the coil clean. Use
a brush, vacuum cleaner attachment, or other suitable
means. If water is used to clean the coil, be sure the power
to unit is shut off prior to cleaning.
NOTE − Care should be used when cleaning the coil so that
the coil fins are not damaged.
Do not permit the hot condenser air discharge to be ob
structed by overhanging structures or shrubs.
To Clean Burners
Remove them from the furnace as explained in Burner In
structions." Vacuum and/or brush as required.
Vent Outlet
Visually inspect vent outlet periodically to make sure that the
buildup of soot and dirt is not excessive. If necessary, clean
to maintain adequate opening to discharge flue products.
Cleaning Flue Passages & Heating Elements
With proper combustion adjustment the heat exchanger of a
gasfired furnace will seldom need cleaning. If the heat ex
changer should become sooted, it can be cleaned as follows:
1 − Remove the burner assembly as outlined in BURNER
INSTRUCTIONS."
2 − Remove the combustion air inducer.
3 − At the bottom of the heat section, remove the screws
holding the flue collector box. Carefully remove the
flue collector box without ripping the adjacent insula
tion.
4 − Using a wire brush on a flexible wand, brush out the
inside of each heat exchanger from the burner inlet
and flue outlet ends.
5 − Brush out the inside of the flue collector box.
6 − Run the wire brush down the heat exchanger tubes
from the flue collector end.
7 − If soot buildup is excessive, remove the vent motor
and clean the wheel and housing. Run the wire brush
down the flue extension at the outlet of the vent hous
ing.
8 − After brushing is complete, blow all brushed areas with
air. Vacuum as needed.
9 − Replace parts in the reverse order they were removed
in steps 1 to 3.
10 − When replacing the flue collector box, be careful not to
tear the adjoining insulation.
11 − Assure that all joints on the vent side of the combustion
system are air tight. Apply a high temperature
(+500_F) sealing compound where needed.
Troubleshooting
Draft motor operates and furnace lights but circulating air
blower does not start after the time delay circuit expires
with room thermostat fan switch set to AUTO.
a − Set fan switch to on." If blower motor runs, go to step f.
If it does not, check to see if line voltage is being sup
plied to the high voltage side of the blower time delay
relay (TDR) contacts.
b − If TDR" is closed, touch the supply air blower motor
housing. If it is hot, the motor may be off on internal
protection. Allow time for the internal overload to reset.
Disconnect power to the unit and check the blower
motor capacitor. If it is defective, replace it with one of
the equal capacitance and voltage.
c −If TDR" is closed and the blower motor still does not
run, replace the blower motor.
d −If TDR" is not closed check for 24 volts at W on the
TDR." If 24 volts are present, replace the blower/igni
tion control board.
e −If the blower motor runs with the fan switch in the on"
position but does not run soon after the furnace has ig
nited with the fan switch in the Auto" position, check
for loose 24 volt wires between TDR" and the trans
former.
Thermostat calls for heat but the draft motor does not
come on.
a −The draft motor has internal protection. If the motor
shell is hot to the touch, allow time for the internal over
load to reset.
b −If the motor shell is cold with the room thermostat call
ing for heat, check to see that there is 208/230 volts
between L1 blower/ignition control and black line wire
to draft motor. If no voltage present, check all connec
tions. If the draft motor still does not operate, then
check for 208/230 volts between combustion blower/
ignition control and black line wire to draft motor. If volt
age is not present and there is voltage between L1 on
blower/ignition control and black line wire and 24 volts
present at TS, then replace the blower/ignition control.
Draft motor runs but the furnace does not light.
a −Check all connections on the PSW circuit of blower/
ignition control and make sure the rollout switch and
high limit switch are all closed circuits.
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b −If electrode/flame sensor sparks but has 0" voltage at
the valve during tries for ignition, check the wiring be
tween valve and blower/ignition control, check valve
ground.
c −If electrode/flame sensor sparks 24 volts to valve,
flame is established but does not hold in, check
ground between module and burner, make sure that
the electrode/flame sensor is properly located in the
middle of the flame stream, check system ground.
Check to see if electrode/flame sensor is located in the
flame stream properly.
d) If electrode/flame sensor sparks 24 volts to valve but
system fails to ignite, check to make sure that the gas
supply and gas valve are on, check to see if orifice
plugged, and make sure electrode/flame sensor are
properly located.
Furnace lights and flame rollout occurs or burners have
delayed ignition.
a) Make sure that the carryovers on adjoining burners
are screwed fast and are level with respect to one
another.
b) Make sure electrode/flame sensor is properly located.
c) Make sure all air is purged from gas lines.
Main burners light, but exhibit erratic flame characteristics.
Check the main burner orifices for obstruction and align
ment. Removal procedure is described in Burner Instruc
tions." Clean or replace burner orifices and burners as
needed.
LED Codes & Flash Rates
The following blower/ignition control board (DS1) LED
codes will indicate normal or abnormal operations:
Slow Flash
Normal operation, no call for heat
One flash per second
Fast Flash
Normal operation, call for heat
Two flashes per second.
2 Flash
System lockout − failed to detect or sustain flame
Two flashes in one second with a one second pause.
3 Flash
Pressure switch open or closed
Three flashes in one and one−half seconds with a one sec
ond pause.
4 Flash
High limit /or rollout switch open
Four flash in two seconds with a one second pause.
5 Flash
Flame sensed and gas valve not energized
Five flashes in two and one−half seconds with a one second
pause.
Steady
Internal failure (micro−controller failure; self−check)
Repair Parts & Accessories
The following repair parts are available from your local dealer. When ordering parts, include the complete model number
and serial number which are printed on the unit rating plate.
Control Group Blower Group Heating Group
Rollout Switch Blower Housing Assembly Gas Manifold
Transformer Blower Wheel Main Burner Orifices
Limit Control Blower Motor Main Burners
Gas Valve Blower Motor Mount Heat Exchanger
Blower/Ignition Control Blower Motor Capacitor (if used) Cooling Group
Electrode Combustion Air Inducer Compressor
Flame Sensor Fan Blade Evaporator Coil
Auxiliary Limit Fan Motor Drier
Pressure Switch Fan Motor Capacitor Cap. Tube or Expansion Valve
Contactor
Capacitor
Condenser Coil
Accessories
Description Kit Number LENNOX Cat.
Number
Low Ambient Control ALOAM111−1 42K88
High Pressure Cut−out Kit AHPSW436−1 42K89
Timed Off Control ATIMR446−1 42K90
LP Gas Conversion ALPKTS533−1 42K91
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