TECHNICAL MANUAL
GMS8 33-3/8" Gas Furnace Units
80%AFUE, Single Stage,
Multi-Speed, Upflow Horizontal
Refer to Service Manual RS6612006 for troubleshooting information.
Refer to the appropriate Parts Catalog for part number information.
Model numbers listed on page 3.
•
•
•
This manual is to be used by qualified, professionally trained HVAC technicians
only. Goodman does not assume any responsibility for property damage or
personal injury due to improper service procedures performed by an unqualified
person.
RT6621031r2
November 2013
Copyright © 2013 Goodman Manufacturing Company, L.P.
PRODUCT IDENTIFICATION
The model and manufacturing number are used for positive identification of component parts used in manufacturing.
Please use these numbers when requesting service or parts information.
GMS81405DNCC
GMS80403A*BB
GMS80603A*BB
GMS80604B*BB
GMS80804B*BB
GMS80805C*BB
GMS81005C*BB
GMS81205D*BA
*These models available in Natural Gas and Low NOx.
The United States Environmental Protection Agency (“EPA”) has issued various regulations re-
garding the introduction and disposal of refrigerants introduced into this unit. Failure to follow
these regulations may harm the environment and can lead to the imposition of substantial fines.
These regulations may vary by jurisdiction. Should questions arise, contact your local EPA office.
WARNING
WARNING
Do not connect or use any device
To prevent the risk of property
WARNING
thatisnotdesigncertifiedbyGood-
damage, personal injury, or death,
man for use with this unit. Serious
do not store combustible materials or use gasoline or
property damage, personal injury, reduced unit perfor-
mance and/or hazardous conditions may result from the
use of such non-approved devices.
other flammable liquids or vapors in the vicinity of this
appliance.
3
PRODUCT DESIGN
General Operation
NFPA 54/ANSI Z223.1 - latest edition. In Canada, the fur-
naces must be vented in accordance with the National Stan-
dard of Canada, CAN/CSA B149.1 and CAN/CSA B149.2 -
latest editions and amendments.
The GMS8 furnaces are equipped with an electronic ignition
device used to light the burners and an induced draft blower
to exhaust combustion products.
An interlock switch prevents furnace operation if the inner
blower door is not in place. Keep the blower access door in
place except for inspection and maintenance. (See illustra-
tion on pages 5 and 6.)
NOTE: The vertical height of the Category I venting system
must be at least as great as the horizontal length of the
venting system.
This furnace is also equipped with a self-diagnosing elec-
tronic control module. In the event a furnace component is
not operating properly, the control module LED will flash on
and off in a factory-programmed sequence, depending on
the problem encountered. This light can be viewed through
the observation window in the blower access door. Refer to
the Troubleshooting Chart for further explanation of the LED
codes and Abnormal Operation - Integrated Ignition Control
section in the Service Instructions for an explanation of the
possible problem.
Accessibility Clearances (Minimum)
Unobstructed front clearanace of 24" for servicing is rec-
ommended.
MINIMUM CLEARANCE TO COMBUSTIBLE MATERIALS - INCHES
Vent
Sides
1
Rear
0
Front*
3
Top
1
SW
6
B
1
*
24" clearnace for serviceability recommended.
** Single Wall Vent (SW) to be used only as a conncetor.
Refer to the venting tables outlined in the Installation Manual for
additional venting requirements.
The rated heating capacity of the furnace should be greater
than or equal to the total heat loss of the area to be heated.
The total heat loss should be calculated by an approved
method or in accordance with “ASHRAE Guide” or “Manual
J-Load Calculations” published by the Air Conditioning Con-
tractors of America.
Note: In all cases accessibility clearance shall take prece-
dence over clearances from the enclosure where accessibil-
ity clearances are greater. All dimensions are given in inches.
*Obtain from: American National Standards Institute 1430
Broadway New York, NY 10018
High Altitude Derate
IMPORTANT NOTE: The furnace as shipped requires no
change to run between 0 - 5500 feet. Do not attempt to
increase the firing rate by changing orifices or increasing
the manifold pressure below 5500 feet. This can cause poor
combustion and equipment failure.
Location Considerations
•
•
•
The furnace should be as centralized as is practical
with respect to the air distribution system.
High altitude installations above 5500 feet may require both
a pressure switch and an orifice change. These changes
are necessary to compensate for the natural reduction in
the density of both the gas fuel and the combustion air at
higher altitude.
Do not install the furnace directly on carpeting, tile, or
combustible material other than wood flooring.
When installed in a residential garage, the furnace
must be positioned so the burners and ignition source
are located not less than 18 inches (457 mm) above
the floor and protected from physical damage by ve-
hicles.
For installations above 5500 feet, please refer to your dis-
tributor for required kit(s). Contact the distributor for a tabu-
lar listing of appropriate manufacturer’s kits for propane gas
and/or high altitude installations. The indicated kits must be
used to insure safe and proper furnace operation. All conver-
sions must be performed by a qualified installer, or service
agency.
Notes:
WARNING
O PREVENT POSSIBLE PERSONAL INJURY OR DEATH DUE TO ASPHYXIATION,
T
THIS FURNACE MUST BE ATEGORY VENTED.
O NOT VENT USING
D
C
I
ATEGORY
C
VENTING.
III
Category I Venting is venting at a non-positive pressure. A
furnace vented as Category I is considered a fan-assisted
appliance and the vent system does not have to be “gas
tight.” NOTE: Single stage gas furnaces with induced draft
blowers draw products of combustion through a heat ex-
changer allowing, in some instances, common venting with
natural draft appliances (i.e. water heaters). All installations
must be vented in accordance with National Fuel Gas Code
4
COMPONENT IDENTIFICATION
Tubular Heat Exchanger
1
2 Pressure Switch
3
Flue Pipe Connection
Induced Draft Blower
4
?
Gas Line
Entrance
5
6
Gas Valve
7
Rollout Limit
8
Junction Box
Wiring Harness
Grommet
9
Gas Manifold
Inshot Burner
Gas Line Entrance
(Alternate)
Transformer
Circulator Blower
Blower Door
Interlock Switch
Note: Primary Limit Not Shown
Integrated Control Module
Upflow/Horizontal
1
2
3
4
5
6
7
8
Tubular Heat Exchanger
9 Wiring Harness Grommet
Pressure Switch
Flue Pipe Connection
Induced Draft Blower
Gas Line Entrance
Gas Valve
10 Gas Manifold
11 Inshot Burner
12 Transformer
13 Integrated Control Module
14 Blower Door Interlock Swtich
15 Circulator Blower
Rollout Limit
Junction Box
16 Gas Line Entrance (Alternate)
5
PRODUCT DIMENSIONS
GMS8
Alt. Gas Inlet
Alt. Gas Inlet
Alt. High Voltage
Alt. LowVoltage
High Voltage Inlet
Low Voltage
MODEL
A
B
GMS80403A***
GMS80603A***
GMS80604B***
GMS80804B***
GMS80805C***
GMS81005C***
14
12 - 1/2
17 - 1/2
16
21
19 - 1/2
23
GMS81205D***
GMS81405DN**
24 - 1/2
6
GMS8[040-100]BB
GMS81205D*BA
GMS81405DNCC
PRODUCT DIMENSIONS
Pressure Switch Trip Points
Trip Point
ID Blower
Pressure
Sw itch
ID Blower
Pressure
Sw itch
Model
Part #
-0.70
-0.75
-0.75
-0.70
-0.75
-0.70
-0.80
-0.80
B1370158
B1370179
B1370179
B1370158
B1370179
B1370158
0130F00042
0130F00042
GMS80403A*BB
GMS80603A*BB
GMS80604B*BB
GMS80804B*BB
GMS80805C*BB
GMS81005C*BB
GMS81205D*BA
GMS81405DNCC
For installations in Canada, the GMS furnaces are certifed only to 4,500 ft.
* Negative pressure readings are in inches of water column (*w.c.)
PRIMARY LIMIT
Part Number
Open Setting (°F)
GMS80403A*BB
GMS80603A*BB
GMS80604B*BB
GMS80804B*BB
GMS80805C*BB
GMS81005C*BB
20162901
20162904
20162903
210
1
150
---
1
160
---
---
---
---
1
---
---
---
---
---
1
1
---
1
---
GMS81205D*BA
GMS81405DNCC
---
---
---
---
1
1
AUXILIARY LIMIT SWITCHES
ROLLOUT LIMIT SW ITCHES
Part Number
Open Setting (°F)
GMS80403A*BB
GMS80603A*BB
GMS80604B*BB
GMS80804B*BB
GMS80805C*BB
GMS81005C*BB
0130F00038
Part Number
Open Setting (°F)
GMS80403A*BB
GMS80603A*BB
GMS80604B*BB
GMS80804B*BB
GMS80805C*BB
GMS81005C*BB
10123529
120
1
300
2
1
2
1
2
1
2
1
2
1
2
GMS81205D*BA
GMS81405DNCC
1
1
GMS81205D*BA
GMS81405DNCC
2
2
7
PRODUCT DESIGN
Thermostats:
It is recommended that a single-stage heat, non-power robbing thermostat be used. Refer to the product marketing
literature for a complete list of thermostats offered.
THERMOSTATS
Thermostat
Man/Auto
Programmable
Cool Heat Batt. Powered Batt. Bkup
1213406*
1213407
1213411
Man. Or Auto
Man. Changeover
Man. Changeover
Yes
Yes
No
2
2
2
3
2
2
No
Yes
Yes
No
Yes
No
*1213406 is the recommended model for the G*S* furnaces when used with a heat pump in a fossil fuel application.
It is NOT for use with the G*S8 as a sole heating source. 1213406 thermstats are 24V powered with battery
backup.
Filters:
Filters are required with this furnace and must be provided by the installer. The filters used must comply with UL900 or
CAN/ULCS111 standards. Installing this furnace without filters will void the unit warranty
Upflow Filters
SIDE RETURN
Nominal
BOTTOM RETURN
Approx.
Approx.
Cabinet
Width
(in.)
Cabinet
Width
(in.)
Nominal
Filter Size
(in.)
Flow Area
Flow Area
(in2)
Filter Size
(in.)
(in2)
All
16 x 25 x 1
400
17-1/2
21
14 x 25 x 1
16 x 25 x 1
20 x 25 x 1
350
400
24-1/2
500
RefertoMinimumFilterAreatablestodeterminefilterarearequirement.NOTE: Filterscanalsobeinstalledelsewherein
the duct system such as a central return.
MINIMUM FILTER SIZES for DISPOSABLE FILTERS
FURNACE INPUT
FILTER SIZE
320 in2
40M
60M
483 in2
80M
100M
120M
140M
640 in2
800 in2
738 in2
738 in2
DISPOSABLE NOMINAL 300 F.M. FACE VELOCITY
8
GMS8[040-100]BB
GMS81205D*BA
GMS81405DNCC
FURNACE SPECIFICATIONS
MODEL
Btuh Input (US) High Fire
Output (US) High Fire
A.F.U.E.
40,000
32,000
80%
60,000
48,000
80%
60,000
48,000
80%
80,000
64,000
80%
80,000
64,000
80%
100,000
80,000
80%
120,000
96,000
80%
140,000
112,000
80%
Rated External Static (" w.c.)
Temperature Rise (°F)
.20 - .50
25 - 55
.20 - .50
25 -55
.20 - .50
20 - 50
.20 - .50
35 - 65
.20 - .50
35 - 65
.20 - .50
35 - 65
.20 - .50
40 - 70
.20 - .50
40 - 70
High Stage Pressure Switch
Trip Point (" w.c.)
-0.70
-0.75
-0.75
-0.70
-0.75
-0.70
-0.80
-0.80
Blower Wheel (D" x W")
Blower Horsepower
10 X 6
1/3
10 x 6
1/3
10 x 8
1/2
10X8
1/2
10x10
1/2
10X10
1/2
11x10
3/4
11x10
3/4
Blower Speeds
4
4
4
4
4
4
4
4
Max CFM @ 0.5 E.S.P.
Power Supply
1298
1157
1883
1725
1960
1974
2131
2131
115-60-1 115-60-1 115-60-1 115-60-1 115-60-1 115-60-1 115-60-1 115-60-1
Minimum Circuit Ampacity (MCA)(1)
Maximum Overcurrent Device(2)
Transformer (VA)
8.5
15
8.5
15
12.9
15
12.9
15
12.9
15
12.9
15
15.2
15
14.7
15
40
40
40
40
40
40
40
40
Heat Anticipator (Amps)
Primary Limit Setting (°F)
Auxiliary Limit Setting (°F)
Rollout Limit Setting (°F)
0.7
0.7
0.7
0.7
0.7
0.7
0.7
0.7
210°
120°
300°
150°
120°
300°
150°
120°
300°
150°
120°
300°
160°
120°
300°
150°
120°
300°
160°
120°
300°
160°
120°
300°
Gas Supply Pressure
7 / 11
7 / 11
7 / 11
7 / 11
7 / 11
7 / 11
7 / 11
7 / 11
(Natural/Propane) (" w.c.)
Manifold Pressure
3.5 / 10
3.5 / 10
3.5 / 10
3.5 / 10
3.5 / 10
3.5 / 10
3.5 / 10
3.5 / 10
(Natural/Propane) High Stage (" w.c.)
Orifice Size (Natural/Propane)
Number of Burners
#45 / #55 #45 / #55 #45 / #55 #45 / #55 #45 / #55 #45 / #55 #45 / #55 #43 / #55
2
4
3
4
3
4
4
4
4
4
5
4
6
4
6
4
Vent Connector Diameter (inches)(3)
Shipping Weight (lbs.)
84
88
98
106
114
118
130
130
(1) Wire size should be determined in accordance with National Electrical Codes. Extensive wire runs will require larger wire sizes.
(2)
Maximum Overcurrent Protection Device: May use Time Delay Fuse or HACR type Circuit Breaker of the same size as noted.
(3) See Installation Instructions for appropriate vent diameter, length and number of elbows.
1. These furnaces are manufactured for natural gas operation. Optional Kits are available for conversion to propane gas operation.
2. For elevations above 2000 ft. the rating should be reduced by 4% for each 1000 ft. above sea level. The furnace must not be derated, orifice
changes should only be made if necessary for altitude.
3. The total heat loss from the structure as expressed in TOTAL BTU/HR must be calculated by the manufactures method in accordance with the
"A.S.H.R.A.E. GUIDE" or "MANUAL J-LOAD CALCULATIONS" published by the AIR CONDITIONING CONTRACTORS OF AMERICA. The total
heat loss calculated should be equal to or less than the heating capacity. Output based on D.O.E. test procedures, steady state efficiency times
output.
4. Minimum Circuit Ampacity calculated as: (1.25 x Circulator Blower Amps) + I.D. Blower Amps.
Unit specifications are subject to change without notice. ALWAYS refer to the unit's serial plate for the most up-to-date general and electrical information.
9
GMS8[040-100]BB
GMS81205D*BA
GMS81405DNCC
BLOWER PERFORMANCE SPECIFICATIONS
(CFM & Temperature Rise vs. External Static Pressure)
Model
EXTERNAL STATIC PRESSURE (Inches Water Colum n)
0.2 0.3 0.4 0.5
Tons AC
at 0.5"
ESP
3.0
2.5
2.0
1.5
3.0
2.5
2.0
1.5
4.0
3.5
3.0
2.5
4.0
3.5
3.0
2.5
5.0
4.0
3.5
3.0
5.0
4.0
3.5
3.0
5.0
4.0
3.5
3.0
5.0
4.0
3.5
3.0
Motor
Speed
0.1
0.6
0.7
0.8
Heating Speed
As Shipped
CFM RISE CFM RISE CFM RISE CFM RISE CFM RISE CFM CFM CFM
1521 ---- 1466 ---- 1414 ---- 1373 ---- 1298 ---- 1243 1164 1075
1160 26 1160 26 1132 26 1121 26 1082 27 1042 997 925
HIGH
MED
*MS80403A*BB
(MEDIUM)
MED-LO
LOW
961
781
31
38
955
785
31
38
948
781
31
38
932
773
32
38
913
761
33
32
882 821 803
745 716 668
HIGH
MED
1422 31 1352 33 1307 34 1197 37 1157 38 1092 1075 983
*MS80603A*BB
(MEDIUM)
1098 40 1081 41 1051 42 1039 43 1021 44
983 924 868
818 792 728
677 649 626
MED-LO
LOW
919
758
48
913
741
49
892
741
50
847
733
----
----
829
699
----
----
----
----
----
HIGH
MED
2134 21 2100 21 2042 22 1975 23 1883 24 1786 1700 1601
1668 27 1663 27 1656 27 1645 27 1616 28 1549 1492 1391
1419 31 1426 31 1426 31 1432 31 1419 31 1378 1328 1261
1134 39 1145 39 1166 38 1171 38 1160 38 1144 1111 1071
2051 ---- 1983 ---- 1895 ---- 1812 ---- 1725 ---- 1627 1530 1439
1736 ---- 1708 35 1652 36 1611 37 1540 38 1475 1394 1307
1693 35 1668 36 1459 41 1429 41 1389 43 1339 1274 1204
1200 49 1185 50 1180 50 1173 51 1158 51 1125 1125 1080
2290 ---- 2229 ---- 2155 ---- 2047 ---- 1960 ---- 1837 1712 1584
1852 ---- 1820 ---- 1777 ---- 1719 --- 1641 36 1567 1469 1382
1615 37 1592 37 1556 38 1516 39 1470 40 1405 1346 1235
1290 46 1285 46 1265 47 1235 48 1214 49 1174 1044 904
2323 ---- 2225 ---- 2120 35 2040 36 1974 38 1801 1688 1577
1858 40 1847 40 1799 41 1744 42 1674 44 1577 1493 1399
1596 46 1587 47 1571 47 1552 48 1493 50 1397 1326 1217
1291 57 1272 58 1261 59 1257 59 1205 61 1168 1118 1060
2469 ---- 2389 ---- 2300 ---- 2223 40 2131 42 2027 1902 1786
1575 56 1558 57 1545 58 1513 59 1500 59 1419 1354 1271
1402 63 1380 64 1343 66 1319 67 1296 69 1245 1183 1106
1200 ---- 1186 ---- 1161 ---- 1127 ---- 1082 ---- 1042 995 926
2469 42 2389 43 2300 45 2223 47 2131 49 2027 1902 1786
1575 66 1558 67 1545 67 1513 69 1500 69 1419 1354 1271
1402 ---- 1380 ---- 1343 ---- 1319 ---- 1296 ---- 1245 1183 1106
1200 ---- 1186 ---- 1161 ---- 1127 ---- 1082 ---- 1042 995 926
*MS80604B*BB
(MEDIUM)
MED-LO
LOW
HIGH
*MS80804B*BB
(MEDIUM)
MED
MED-LO
LOW
HIGH
*MS80805C*BB
(MEDIUM)
MED
MED-LO
LOW
HIGH
MED
*MS81005C*BB
(MEDIUM)
MED-LO
LOW
HIGH
*MS81205D*BA
(MEDIUM)
MED
MED-LO
LOW
HIGH
MED
GMS81405DNCC
(MEDIUM)
MED-LO
LOW
NOTES:
•
•
•
•
•
CFM in chart is without filter(s). Filters do not ship with this furnace, but must be provided by the installer.
All furnaces ship as hig-speed cooling. Installer must adjust blower cooling speed as needed.
For most jobs, about 400 CFM per ton when cooling is desirable
INSTALLATION IS TO BE ADJUSTED TO OBTAIN TEMPERATURE RISE WITHIN THE RANGE SPECIFIED ON THE RATING PLATE.
The chart is for information only. For satisfactory operation, external static pressure must not exceed values shown on the rating plate. The shaded area insicated
ranges in excess of maximum static pressure allowed when heating.
•
•
The dashed (---) areas indicate a temperature rise not recommended for this model.
At higher altitudes, a properly de-rated unit will have approximatley the same temperature rise at a particular CFM, while ESP at the CFM will be lower.
10
BLOWER PERFORMANCE SPECIFICATIONS
E I S E T U P E T E
11
WIRING DIAGRAMS
GMS8
INTEGRATED
CONTROLMODULE
HUMIDIFIER
XFMR (6)
WARNING:DISCONNECT POWER BEFORE
SERVICING.WIRING TO UNIT MUST BE
PROPERLY POLARIZED AND GROUNDED.
GND
24 VAC
HUMIDIFIER
GND (8)
MVC (9)
GAS
VALVE
C2
W
C
G
R
Y
M1
MV (12)
C
DIAGNOSTIC
LED
ID BLOWER
PRESSURE
SWITCH
AUXILIARY
LIMITCONTROLS
FUSE
OR
G
Y
NO
PS (10)
PSO (4)
HLI (7)
C
3
2
1
4
TO
MICRO
6
9
5
8
YL
W
HLO (1)
7
RD
AUTO RESET
PRIMARY
LIMIT
12
10
11
YL
R
RO2 (11)
RO1 (5)
BR
CONTROL
AUXILI ARY
LIMITS
INTEGRATED
CONTROLMODULE
MANUAL RES ET ROLLOUT
LIMITCONTROL(S)
(SINGLE CONTROL ON SOME MODELS)
24 VAC
XFMR (3)
40VA
TRANSFORMER
2
BR
1
XFMR-H
FP (2)
115 VAC
XFMR-N
FLAME SENSOR
HOT SURFACE
IGNITER
IGN
IGN-N
115 VAC HOT AND PARK TERMINALS
LINE-H XFMR-H HEAT-H COOL-H
ID
BLWR
IND
IND-N
CIR-N
COOL-H
24V
BK
BK
CIRCULATOR
BLWR
115V
XFMR
WH
HEAT-H
15 PIN PLUG
ON SOME MODELS
BLOWER COMPARTMENT
LINE-N
LINE-H
DOOR
JUNCTIONBOX
BURNER COMPARTMENT
24 VAC
HUMIDIFIER
DOOR SWITCH
SWITCH
SWITCH LOCATED INBLOWER
COMPARTMENT ON SOME MODELS
NO
C
YL
WARNING:
RD
RD
DISCONNECT POWER
BEFORE SERVICING.
WIRING TO UNIT
MUST BE
DISCONNECT
PRESSURE
SWITCH
YL
PRIMARY LIMIT
PROPERLY
POLARIZED
AND GROUNDED.
WH
BK
L
GND
N
TO 115VAC/
1
BR
Ø /60 HZ POWER SUPPLY WITH
BL
OVERCURRENT PROTECTION DEVICE
OR
BK
JUNCTION
BOX
C2
HOT
SURFACE
IGNITER
M1
FLAME
SENSOR
LINE-N
GND
GAS VALVE
LINE H
PU
INDUCED DRAFT
BLOWER
TO 115 VAC/ 1/60HZ
POWERSUPPLY WITH
OVERCURRENT PROTECTION
DEVICE
PU
PU
ROLLOUT LIMITS
(SINGLE CO NTROL ON SOME MODELS)
0
STEADY ON
= NORMAL OPERATION
= CONTROL FAILURE
LOW VOLTAGE (24V)
LOW VOLTAGE FIELD
HI VOLTAGE (115V)
HI VOLTAGE FIELD
JUNCTION
EQUIPMENT GND
FIELD GND
OFF
1
2
3
4
5
6
7
C
1 FLASH
= SYSTEM LOCKOUT (RETRIES/RECYCLES EXCEEDED)
= PRESSURE SWITCH STUCK CLOSED
2 FLASHES
FIELD SPLICE
SWITCH (TEMP.)
IGNITER
3 FLASHES
4 FLASHES
5 FLASHES
= PRESSURE SWITCH STUCK OPEN
= OPEN HIGH LIMIT
= FLAME SENSE WITHOUT GAS VALVE
TERMINAL
6 FLASHES
7 FLASHES
= OPEN ROLLOUT
SWITCH (PRESS.)
INTERNAL TO
INTEGRATED CONTROL
= LOW FLAME SIGNAL
OVERCURRENT
PROT. DEVICE
RAPID FLASHES = REVERSED 115 VAC POLARITY/VERIFY GND
PLUG CONNECTION
NOTES:
PK PINK
COLOR CODES:
YL YELLOW
OR ORANGE
PU PURPLE
GR GREEN
1. SET HEAT ANTICIPATOR ON ROOM THERMOSTAT AT 0.7 AMPS.
BR BROWN
WH WHITE
BL BLUE
2. MANUFACTURER'S SPECIFIED REPLACEMENT PARTS MUST BE USED WHEN SERVICING.
3. IF ANY OF THE ORIGINAL WIRE AS SUPPLIED WITH THE FURNACE MUST BE
REPLACED, IT MUST BE REPLACED WITH WIRING MATERIAL HAVING A TEMPERATURE
RATING OF AT LEAST 105 C. USE COPPER CONDUCTORS ONLY.
4. BLOWER SPEEDS MUST BEADJUSTED BY INSTALLER TO MATCH THE INSTALLATION
REQUIREMENTS SOAS TO PROVIDE THE CORRECT HEATING TEMPERATURE RISE AND THE
CORRECT COOLING CFM. (SEE SPEC SHEET FOR AIR FLOW CHART)
GY GRAY
RD RED
BK BLACK
5. UNIT MUST BE PERMANENTLY GROUNDED AND CONFORM TO N.E.C. AND LOCAL CODES.
0140F00119-C
Wiring is subject to change, always refer to the wiring diagram on the unit for the most up-to-date wiring.
12
SCHEMATICS
GMS8
HIGH VOLTAGE!
DISCONNECT ALL POWER BEFORE SERVICING OR INSTALLING THIS
UNIT. MULTIPLE POWER SOURCES MAY BE PRESENT. FAILURE TO
DO SO MAY CAUSE PROPERTY DAMAGE, PERSONAL INJURY OR DEATH.
CIRCULATOR
BLOWER
INDUCER
CIR
NEU
HEAT COOL
K2
PARK PARK
IND
R
RO2
RO1
UT
ROLLO
SWITCH
K3
TH
K1
XFMR
HOT
24 VAC
XFMR
NEU
.0005
3M
COMPRESSOR
CONTACTOR
COIL
TR
C
FACTORY
JUMPER
K8
R
K5
FACTORY
JUMPER
Y
G
W
Y
G
W
GND
IGN
PS
MV MV
HLI
HLO
FP
PSO
THERMOSTAT
FLAME
SENSOR
PROBE
AUX
LIMIT
HIGH
LIMIT
GAS
VALVE
IGNITOR
PRESSURE
SWITCH
TYPICAL SCHEMATIC
GMS8 * MODEL FURNACES
WR 50T55-289 INTEGRATED IGNITION CONTROL
This schematic is for reference only. Not all wiring is as shown above. Always refer to the appropriate wiring diagram for the unit being serviced.
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