58GFA
Induced Combustion Furnaces
Service and Maintenance Instructions
For Sizes 065-150 Series 130
NOTE: Read the entire instruction manual before starting the
installation.
These procedures are for sizes 65,000 through 150,000 Btuh units.
CANADIAN GAS ASSOCIATION
Index
Page
ama
®
A PPROVED
R
SAFETY CONSIDERATIONS.....................................................1
CARE AND MAINTENANCE..................................................1-4
Air Filter Arrangement.............................................................2
Blower Motor and Wheel......................................................2-3
Cleaning Heat Exchanger......................................................3-4
Electrical Controls and Wiring.................................................4
Pilot ...........................................................................................4
Troubleshooting ........................................................................4
Unit Wiring Diagram ............................................................5-6
Troubleshooting Chart ..............................................................7
SAFETY CONSIDERATIONS
Installing and servicing heating equipment can be hazardous due to
gas and electrical components. Only trained and qualified person-
nel should install, repair, or service heating equipment.
Untrained personnel can perform basic maintenance functions
such as cleaning and replacing air filters. All other operations must
be performed by trained service personnel. When working on
heating equipment, observe precautions in the literature, on tags,
and on labels attached to or shipped with the unit and other safety
precautions that may apply.
Follow all safety codes. In the United States, follow all safety
codes including the National Fuel Gas Code NFPA No. 54-
1992/ANSI Z223.1-1992 (NFGC). In Canada, refer to the current
edition of the National Standard of Canada CAN/CGA-B149.1-
and .2-M95 Natural Gas and Propane Gas Installation Codes
(NSCNGPIC). Wear safety glasses and work gloves. Have fire
extinguisher available during start-up and adjustment procedures
and service calls.
A92057
Fig. 1—Model 58GFA Upflow
The ability to properly perform maintenance on this equip-
ment requires certain expertise, mechanical skills, tools and
equipment. If you do not possess these, do not attempt to
perform any maintenance on this equipment other than those
procedures recommended in the User’s Manual. FAILURE
TO FOLLOW THIS WARNING COULD RESULT IN
POSSIBLE DAMAGE TO THIS EQUIPMENT, SERIOUS
PERSONAL INJURY, OR DEATH.
Recognize safety information. This is the safety-alert symbol
.
When you see this symbol on the furnace and in instructions or
manuals, be alert to the potential for personal injury.
Understand the signal word DANGER, WARNING, or CAU-
TION. These words are used with the safety-alert symbol. DAN-
GER identifies the most serious hazards which will result in severe
personal injury or death. WARNING signifies a hazard that could
result in personal injury or death. CAUTION is used to identify
unsafe practices which would result in minor personal injury or
product and property damage. NOTE is used to highlight sugges-
tions that will result in enhanced installation, reliability, or
operation.
CARE AND MAINTENANCE
For continuing high performance and to minimize possible equip-
ment failure, it is essential that periodic maintenance be performed
on this equipment. Consult your local dealer as to the proper
frequency of maintenance and the availability of a maintenance
contract.
Manufacturer reserves the right to discontinue, or change at any time, specifications or designs without notice and without incurring obligations.
Book
Tab 6a 8a
1
4
PC 101
Catalog No. 535-821
Printed in U.S.A.
Form 58GFA-1SM
Pg 1
10-95
Replaces: 58D, G-3SM
6. Mark blower wheel, motor, and motor support in relation to
blower housing before disassembly to ensure proper reassem-
bly.
e. Gas valve
f. Edge connector leading to control box
4. Remove 8 screws that secure flue collector box to center
panel. Be careful not to damage sealant.
7. Loosen setscrew holding blower wheel on motor shaft.
8. Remove bolts holding motor mount to blower housing and
slide motor and mount out of housing. Disconnect ground wire
attached to blower housing before removing motor.
5. Remove complete inducer assembly from furnace, exposing
flue openings.
6. Clean cells using field-provided small wire brush, steel spring
cable, reversible electric drill, and vacuum cleaner.
9. Lubricate motor (when oil ports are provided).
a. Remove dust caps or plugs from oil ports located at each
end of motor.
a. Assemble wire brush and steel spring cable.
(1.) Use 48 in. of 1/4-in. diameter high-grade steel spring
cable (commonly known as drain clean-out or Roto-
Rooter cable).
b. Use a good grade of SAE 20 nondetergent motor oil and
put 1 teaspoon, 5 cc, 3/16 oz, or 16 to 25 drops in each oil
port. Do not over-oil.
(2.) Use 1/4-in. diameter wire brush (commonly known as
25-caliber rifle cleaning brush).
c. Allow time for total quantity of oil to be absorbed by each
bearing.
NOTE: The items needed in steps (1.) and (2.) can usually be
purchased at local hardware stores.
d. Wipe excess oil from motor housing.
e. Replace dust caps or plugs on oil ports.
10. Remove blower wheel from housing.
a. Mark cutoff location to ensure proper reassembly.
(3.) Insert twisted wire end of brush into end of steel spring
cable, and crimp tight with crimping tool or strike with
ball-peen hammer. TIGHTNESS is very important.
b. Remove screws holding cutoff plate and remove cutoff
plate from housing.
(4.) Remove metal screw fitting from wire brush to allow
insertion into cable.
c. Lift blower wheel from housing through opening.
b. Clean each heat exchanger cell.
11. Clean blower wheel and motor using a vacuum cleaner with
soft brush attachment. Do not remove or disturb balance
weights (clips) on blower wheel blades. The blower wheel
should not be dropped or bent as balance will be affected.
(1.) Attach variable-speed, reversible drill to end of steel
spring cable (end opposite brush).
(2.) Insert brush end of cable into upper opening of cell
and slowly rotate with drill. DO NOT force cable.
Gradually insert at least 36 in. of cable into 2 upper
passes of cell. (See Fig. 3.)
12. Reinstall blower wheel by reversing steps 9 a. through c. Be
sure wheel is positioned for proper rotation.
13. Reassemble motor and blower by reversing steps 2 through 7.
If motor has ground wire, be sure it is connected as before.
Be sure the motor is properly positioned in the blower
housing. The motor oil ports must be at a minimum of 45°
above the horizontal centerline of the motor after the blower
assembly has been reinstalled in the furnace.
14. Reinstall blower assembly in furnace. Connect blower leads to
blower speed selector.
15. Reinstall control assembly.
16. Turn on electrical power and check for proper rotation and
speed changes between heating and cooling.
A91252
17. Replace blower access door.
CLEANING HEAT EXCHANGER
Fig. 3—Cleaning Heat Exchanger Cell
The following steps should be performed by a qualified service
technician:
(3.) Work cable in and out of cell 3 or 4 times to obtain
sufficient cleaning. DO NOT pull cable with great
force. Reverse drill and gradually work cable out.
NOTE: Deposits of soot and carbon indicate the existence of a
problem which needs to be corrected. Take action to correct the
problem.
(4.) Remove burner assembly and cell inlet plates.
(5.) Replace screws in center panel and cells before
cleaning.
If it becomes necessary to clean the heat exchanger because of
carbon deposits, soot, etc., proceed as follows:
(6.) Insert brush end of cable in lower opening of cell, and
proceed to clean 2 lower passes of cell in same manner
as 2 upper passes.
1. Turn off gas and electrical power to furnace.
2. Remove 2 screws that secure relief box. (See Fig. 3.)
3. Disconnect wires to the following components:
a. Draft safeguard switch
(7.) Repeat foregoing procedures until each cell in furnace
has been cleaned.
b. Inducer motor
(8.) Remove residue from each cell using vacuum cleaner.
c. Pressure switch
(9.) Clean burner assembly using vacuum cleaner with soft
brush attachment.
d. Limit overtemperature switch
3
(10.) Reinstall cell inlet plates and burner assembly. Care
must be exercised to center the burners in the cell
openings.
PILOT HEAD V–NOTCH FALLS
DIRECTLY BELOW FRONT EDGE
OF BURNER CARRYOVER.
7. After cleaning flue openings, check sealant on flue collector to
ensure that it has not been damaged. If new sealant is needed,
contact your dealer or distributor.
8. Clean and replace flue collector assembly, making sure all 8
screws are secure.
1
/ ″
8
9. Reinstall 2 screws in relief box.
10. Reconnect wires to the following components:
a. Draft safeguard switch
b. Inducer motor
c. Pressure switch
A91249
d. Limit overtemperature switch
e. Gas valve
Fig. 4—Position of Pilot to Burner
securely. Electrical controls are difficult to check without proper
instrumentation; therefore, reconnect electrical power to unit and
observe unit through 1 complete operating cycle.
f. Edge connector leading to control box
11. Replace blower access doors.
12. Turn on electrical power and gas.
13. Set thermostat and check furnace for proper operation.
The 24-v circuit contains an automotive-type, 3-amp fuse located
on the main control board. Any direct shorts during installation,
service, or maintenance could cause this fuse to blow. If fuse
replacement is required, use ONLY a 3-amp fuse of identical size.
PILOT
Never use a match or other open flame to check for gas leaks.
Use a soap-and-water solution. A failure to follow this
warning could result in fire, personal injury or death.
Check the pilot and clean if necessary at the beginning of each
heating season. The pilot flame should be high enough for proper
impingement of the flame sensing element (or thermocouple) and
to light the burners. Remove the accumulation of soot and carbon
from the flame sensing element (or thermocouple). Refer to Fig. 4
for proper location of pilot on burner assembly.
14. Check for gas leaks.
15. Replace control access door.
ELECTRICAL CONTROLS AND WIRING
TROUBLESHOOTING
NOTE: There may be more than 1 electrical supply to unit.
Page 7 contains a troubleshooting chart. This chart can be a useful
tool in isolating furnace operation problems. Beginning with the
word "Start," answer each question and follow the appropriate
arrow to the next item.
The electrical ground for 115-v wiring must be maintained
properly. Refer to Fig. 5 for field wiring information and to Fig. 6
for unit wiring information.
With power disconnected to unit, check all electrical connections
for tightness. Tighten all screws on electrical connections. If any
smoky or burned connections are noticed, disassemble the connec-
tion, clean all parts and stripped wire, and reassemble properly and
The chart will help identify the problem or failed component. After
replacing any component, verify correct operating sequence as
indicated by bold arrows.
4
FIELD 24-VOLT WIRING
FIELD 115-, 208/230-, 460-VOLT WIRING
FACTORY 24-VOLT WIRING
FACTORY 115-VOLT WIRING
NOTE 2
THERMOSTAT
TERMINALS
W
C
R
G
Y
FIVE
WIRE
FIELD-SUPPLIED
FUSED DISCONNECT
THREE-WIRE
HEATING-
ONLY
208/230- OR
460-VOLT
THREE
PHASE
W
R
BLK
BLK
WHT
WHT
208/230-
VOLT
SINGLE
PHASE
GND
GND
G
AUXILIARY
J-BOX
115-VOLT FIELD-
SUPPLIED
FUSED
DISCONNECT
C
Y
GND
NOTE 1
CONTROL
CONDENSING
UNIT
BOX
TWO
WIRE
24-VOLT
TERMINAL
BLOCK
NOTES: 1. Connect Y-terminal as shown for proper operation.
2. Some thermostats require a "C" terminal connection as shown.
3. If any of the original wire, as supplied, must be replaced, use
same type or equivalent wire.
FURNACE
A95241
Fig. 5—Heating and Cooling Application Wiring Diagram
5
GV
DSS
L2
TO 115V AC FIELD DISCONNECTIONS
NOTE #4
PRS
L1
SCHEMATIC
DIAGRAM
MGV
CONNECTION DIAGRAM
NO
NC
TH
BRN
ILK
TR
C
EQUIPMENT GROUND
PILOT
L1
LO
SPARE-2
L1
MED LO
MED HI
HI
CFR
HFR
HEAT
FL
LS
ALS
START
SPARE-1
COOL
NOTE #9
OL
(WHEN USED)
NOTE #6
CAP
COM
IDM
COM
BLWM
WHT
BLK
EAC-1
EAC-2
IDR
PL1-3
PL1-1
IDM
BLU
TRAN
115V AC
NOTE #4
ILK
FUSED DISCONNECT
SWITCH (WHEN REQ’D)
LS
FL
PR-1
ALS
PR-2
FU1
PL1-4
TRAN
BLK
PL1-7
BLK
FU2
24V AC
3A
SEC-1
SEC-2
FUSE
WHT
NOTE #7
(WHEN USED)
NOTE #6
WHT
GRN
COM
PR2
HFR
PL1
1
2
4
5
6
7
8
9
GRN
PR1
L2
CFR
L1
JB
R
LOGIC
PL1-9
HFR
3
EAC-2
EAC-1
TIME
DELAY
LO
HI
BLWM
GRN
BRN
WHT (COM)
BLK (HI)
GV
TR
MGV
DSS
C
PL1-8
OL
SPARE-1
SPARE-2
Y
TH
PRS
IDR
RED
NOTE #9
YEL (MED HI)
NO
NC
START
PILOT
SEC-2
SEC-1
BLU
BLU (MED LO)
RED (LO)
BRN
PL1-2
PL1-6
IDR
FU1
W
W
Y
R
C
G
GROUND
3AMP
FUSE
SCREW
REQUIRED
IDR
NOTE #7
PCB
CFR
NOTE #8
NOTE #1
G
C
NOTE #9
LEGEND
JUNCTION
ALS
AUXILIARY LIMIT SWITCH, OVERTEMP.
-MANUAL RESET, SPST-(N.C.)
UNMARKED TERMINAL
PCB TERMINAL
BLWM BLOWER MOTOR
NOTES:
CAP
CFR
DSS
CAPACITOR
COOLING FAN RELAY, SPDT
DRAFT SAFEGUARD SWITCH, SPST-(N.C.),
MANUAL RESET
1. Internally connected to equipment ground through mounting screw.
FACTORY POWER WIRING (120 AC)
FACTORY CONTROL WIRING (120 AC)
FIELD POWER WIRING (120 AC)
CONDUCTOR ON PCB
2. If any of the original equipment wire is replaced, use wire rated for 105°C.
3. Blower motor (BLWM) & Inducer motor (IDM) contain auto-reset
thermal overload switch.
EAC-1 ELECTRONIC AIR CLEANER CONNECTION (115 VAC)
EAC-2 ELECTRONIC AIR CLEANER CONNECTION (COMMON)
FL
FUSIBLE LINK
4. Use only copper wire between the disconnect switch and the furnace
junction box (JB).
FU1
FU2
GV
HFR
IDM
IDR
ILK
FUSE, 3 AMP, AUTOMOTIVE BLADE TYPE
FUSE FIELD INSTALLED
GAS VALVE-REDUNDANT OPERATORS
HEATING FAN RELAY, SPST (N.O.)
INDUCED DRAFT MOTOR
INDUCED DRAFT RELAY, SPST-(N.O.)
BLOWER ACCESS PANEL INTERLOCK SWITCH,
SPST-(N.O.)
FIELD WIRING SCREW TERMINAL
FIELD GROUND
5. Symbols are electrical representations only6.
6. Auxiliary limit switch (ALS) used on downflow models only.
7. The transformer 24VAC winding is protected by a 3 AMP automotive
blade type fuse on the control board. A 24VAC short to ground during
installation, checkout, operation, service or maintenance could cause
this fuse to open. Do not replace the 3 AMP fuse with any other size fuse.
8. Blower motor (BLWM) adjustable OFF-DELAY. Factory set: 120 seconds
cut resistor: 180 seconds.
EQUIPMENT GROUND
FIELD SPLICE
PLUG RECEPTACLE
JB
JUNCTION BOX
LS
LIMIT SWITCH, AUTO RESET, SPST(N.C.)
OL
AUTO-RESET INTERNAL MOTOR OVERLOAD TEMP. SW.
PRINTED CIRCUIT BOARD (FURNACE CONTROL)
9-CIRCUIT CONNECTOR (PCB1)
PCB
PL1
PR5
PRESSURE SWITCH, SPDT
TRAN TRANSFORMER (115V AC/24V AC)
9. When CFR relay is energized, HFR relay is also energized.
322876-101 REV. A
A95464
Fig. 6—Unit Wiring Diagram
6
START
Turn on 115-VAC
power to unit.
Disconnect all thermostat
wires from board.
Turn off 115-VAC
power to unit.
NO
Are
Is 24VAC
across screws
W & C or
all thermostat
wires to board
disconnected?
Is 24VAC
across screws
R & C?
YES
YES
YES
Is blower
running?
G & C?
NO
NO
NO
YES
Check/Replace:
1. Limit switch
Jumper across
screws R & G.
Replace
board.
2. Limit shield (if used)
3. Fuse link
4. Auxillary limit switch (if used)
5. Wire harness
YES
Is
Is
Is
Is
YES
NO
NO
24VAC
115VAC
across HI &
COM?
115VAC
across L1 &
L2?
blower running
on cooling
speed?
across screws
R & C?
YES
YES
NO
NO
Replace
blower motor
and/or start
capacitor.
Check/Replace:
1. Unit power
2. Door switch
3. Power harness
Check/Replace:
1. 3-amp board
fuse
Is
NO
115VAC
Replace
board.
across EAC-1
& COM?
2. Transformer
Check pressure
tube for leak or
YES
Is
24VAC
NO
crimp; otherwise,
Replace
board.
Remove
R & G jumper.
across PL1-2
& screw C on
board?
replace pressure switch
NO
YES
YES
Is heat
exchanger
pressure drop greater
than 0.35-in.
wc?
Is 24VAC
across pressure
switch N/O contact
& screw C on
board?
Repair wire
harness.
Does
blower turn
off?
YES
NO
NO
NO
YES
Check/Replace:
1. Vent systems
2. Induce wheel
Is 24VAC
across pressure
switch N/O contact
& screw C on
board?
YES
Check/Replace:
1. Draft safeguard switch
2. Wire harness
Jumper across
screws R & W.
3. Flue choke
4. Inducer voltage
5. Inducer motor bearings
NO
Check/Replace:
1. Pilot
Is
inducer motor
on?
YES
Is
YES
YES
NO
Is
24VAC across gas
valve?
unit lit?
2. Thermocouple
3. Gas valve
NO
YES
Is
Is
Is
Replace
blower motor
and/or start
capacitor.
blower running
on heat speed 45
sec after unit
lights?
YES
NO
115VAC across
inducer motor
connector?
115VAC across
inducer motor
connector?
Replace
inducer motor.
NO
NO
YES
Is
Is
Is
24VAC
YES
NO
24VAC across
PL-2 & screw
C on board?
115VAC
across EAC-1
& COM?
NO
across
PL-1 & screw
C on board?
Replace
board.
Check/Repair
wire harness;
otherwise,
replace
NO
YES
YES
Check/Replace
thermostat
Replace
board.
Remove
R & M jumper.
Repair wire
harness.
and/or
pressure
thermostat wiring.
switch.
NO
After
NO
YES
off-delay
does blower
turn off?
Reconnect all
thermostat wires.
Does unit
operate?
NOTE: After replacing any component, verify correct operating
YES
sequence as indicated by bold arrows.
END OF TEST.
A91253
7
SERVICE TRAINING
Packaged Service Training programs are an excellent way to increase your
knowledge of the equipment discussed in this manual, including:
• Unit Familiarization
• Installation Overview
• Maintenance
• Operating Sequence
A large selection of product, theory, and skills programs is available, using popular
video-based formats and materials. All include video and/or slides, plus companion
book.
Classroom Service Training plus "hands-on" the products in our labs can mean
increased confidence that really pays dividends in faster troubleshooting, fewer
callbacks. Course descriptions and schedules are in our catalog.
CALL FOR FREE CATALOG 1-800-962-9212
[ ] Packaged Service Training
[ ] Classroom Service Training
A94328
Copyright 1995 CARRIER Corp. • 7310 W. Morris St. • Indianapolis, IN 46231
58gfa1sm
Manufacturer reserves the right to discontinue, or change at any time, specifications or designs without notice and without incurring obligations.
Book
Tab 6a 8a
1
4
PC 101
Catalog No. 535-821
Printed in U.S.A.
Form 58GFA-1SM
Pg 8
10-95
Replaces: 58D, G-3SM
|