LG GM-B208SS, GM-B208SW, LFC20760SW/04, LFC20760SW, LFC20760SB Service Manual
...
CAUTION
BEFORE SERVICING THE UNIT,
READ THE SAFETY PRECAUTIONS IN THIS MANUAL.
REFRIGERATOR
SERVICE MANUAL
MODELS:
GM-B208SS
GM-B208SW
CONTENTS
SAFETY PRECAUTIONS .....................................................................................................
1. SPECIFICATIONS ............................................................................................................
2. PARTS IDENTIFICATION .................................................................................................
3. DISASSEMBLY ................................................................................................................
3.1 Door ...........................................................................................................................
3.2 Replacing Refrigerator Room.......................................................................................
3.3 Door Gasket Removal..................................................................................................
3.4 Door Gasker Replacement...........................................................................................
3.5 Door Alignment............................................................................................................
3.6 Fan and fan motor .......................................................................................................
3.7 Defrost control assembly..............................................................................................
3.8 Lamp............................................................................................................................
3.9 Control Box Refrigerator..............................................................................................
3.10 Multi duct...................................................................................................................
4. ADJUSTMENT .................................................................................................................
4.1 Compressor .................................................................................................................
4.2 PTC-Starter .................................................................................................................
4.3 OLP (overload protector) .............................................................................................
4.4 To remove the cover PTC ...........................................................................................
5. CIRCUIT DIAGRAM .........................................................................................................
6. TROUBLESHOOTING ......................................................................................................
6.1 Compressor and electric components .........................................................................
6.2 PTC and OLP ..............................................................................................................
6.3 Other electrical components .......................................................................................
6.4 Service diagnosis chart ...............................................................................................
6.5 Refrigeration cycle ......................................................................................................
7. OPERATION PRINCIPLE AND REPAIR METHOD OF ICEMAKER ...............................
7.1 Operation principle ......................................................................................................
7.2 Ice maker functions .....................................................................................................
7.3 Defect diagnosis function ............................................................................................
8. DESCRIPTION OF FUNCTION & CIRCUIT OF MICOM .................................................
8.1 Function ......................................................................................................................
8.2 PCB function ...............................................................................................................
8.3 Resistance specification of sensor ..............................................................................
8.4 Troubleshooting ...........................................................................................................
8.5 Main PWB assembly and parts list ..............................................................................
8.6 PWB diagram ..............................................................................................................
9. EXPLODED VIEW AND REPLACEMENT PART LIST.....................................................
2
3
4
5
5
5
6
6
7
8
8
8
8
8
9
9
9
10
10
11
12
12
13
14
15
16
18
18
19
20
21
21
25
33
34
36
39
41
SAFETY PRECAUTIONS
Please read the following instructions before servicing your
refrigerator.
1.Check the refrigerator for current leakage.
2.To preven telectric shock,unplug before servicing.
3.Always check line voltage and amperage.
4.Use standard electrical components.
5.Don't touch metal products in the freezer with wet
Hands.This may cause frost bite.
6.Prevent water from spiling on to electric elements or the
Machine parts.
7.Before tilting the refrigerator,remove all materials from
On or in the refrigerator.
8.When servicing the evaporator,wear gloves to prevent
Injuries from the sharp evaporator fins.
9.Service on the refrigerator should be performed by a
Qualified technician.Sealed system repair must be
Performed by a CFC certified technician.
- 2 -
1. SPECIFICATIONS
MODELS
SPECIFICATIONS
Color WHITE STAINLESS
Dimensions
Net Weight
Capacity
Refrigerant
Climate Class
Rated Rating
Cooling System
Temperature Control
Defrosting System
Insulation
Compressor
Evaporator
GENERAL FEATURES
Condenser
Lubricanting Oil
Drier
Capillary Tube
First Defrost
Defrost Cycle
Defrosting Device
Anti-freezing Heater
Case Material
Door material PCM STAINLESS
Handle Type
Basket, Quantity
Ice Tray & Bank
Cover , T/V
Lamp
REFRIGERATOR
Shelf
Tray, meat
Egg Bank
Basket, Quantity
Lamp
Shelf
FREEZER
GM-B208SW GM-B208SS
759 (W) x 818 (D) x 1739 (H) mm
111 kg
20 cu.ft.
R134A(120 g)
TROPICAL (T)
240 V/50Hz
FAN COOLING
MICOM CONTROL
FULL AUTOMATIC
HEATER DEFROST
CYCLO PENTANANE
MQ53LAUM PTC STARTING TYPE
FIN TUBE TYPE
WIRE CONDENSER
10CST@10G 310ml
MOLECULAR SIEVE XH-7
ID Ø 0.75
4 HOURS
7-40 HOURS
SHEATH HEATER
WATER TRANK HEATER
EMBO
08 VISTA
3 LEFT+2 RIGHT
I/B(1EA)
OPTIBIN CRISPER+HUMIDITY CTL 05
YES(2) 40W/BLUE
[1Fix(Full)+2Fix](non S/Proof)
YES
NO
1 PLASTIC
YES(1) 40W/BLUE
1FULL+2FIXED
- 3 -
2. PARTS IDENTIFICATION
A
B
C
D
F
G
H
K
L
M
E
N
O
P
I
J
Use this section to become more familiar with the parts and features.
NOTE: This guide covers several different models. The refrigerator you have purchased may have some
or all of the items listed below. The locations of the features shown below may not match your model.
K
A
Digital Sensor Control
B
Refrigerator Light
C
Shelves
D
Chef Fresh / Snack Pan
E
Can Dispenser *
Optibin Crisper
F
Keeps fruits and vegetable fresh and crisper
G
Custom cube Icemaker *
Ice Tray *
H
I
Durabase
Divider
J
*
Filter (Inside)*
L
Dairy Bin
M
Egg Box *
N
Refrigerator Door Rack
O
Freezer Light
P
Pull out Drawer
*on some models
- 4 -
3. DISASSEMBLY
3-1 DOOR
Left Door
Loosen the cover screw (1).
Disconnect door switch wire (2).
Loosen hinge bolts (3).
Lift off the top hinge (4).
Place the door on a non-scratching surface with
the inside up.
Right Door
Loosen the cover screw (1).
Disconnect door switch wire (2).
Disconnect wire harness (5).
Loosen hinge bolts (3).
Loosen ground screw (6).
Lift off the top hinge (4).
Place the door on a non-scratching surface with
the inside up.
Left Door
Lower the door onto the middle hinge pin (5).
Make sure the door is aligned with the cabinet.
Replace the top hinge (4) installing hinge
screws (3) to secure it.
Make sure the gasket on the door is flush
against the cabinet and is not folded.
Support the door on the handle side while
securing. And make sure the door is straight
and the gap between the doors is even across
the front.
Connect the door switch wire (2).
Tighten the cover screw (1).
Note: To use like reference the previous image.
Left
Figure 1
3-2 REPLACING REFRIGERATOR DOOR
Right Door
Lower the door onto the middle hinge pin (7).
Make sure the door is aligned with the cabinet.
Replace the top hinge (4) installing hinge
screws (3) to secure it.
Make sure the gasket on the door is flush
against the cabinet and is not folded.
Support the door on the handle side while
securing. And make sure the door is straight
and the gap between the doors is even across
the front.
Install the ground screw (6).
Connect the door switch wire (2).
Tighten the cover screw (1).
Right
- 5 -
3-3 DOOR GASKET REMOVAL
1. Remove door frame cover
Starting at top of cover and working down, snap cover
out and away from door.
3-4 DOOR GASKET REPLACEMENT
1. Insert gasket bracket clips
1) Insert gasket bracket edge beneath door frame edge.
2) Turn upper gasket bracket spring so that both spring
ends are in the door channel.
3) Push in clip until you hear it snap securely into place.
Frame Cover
Handle
Figure 2
2. Remove gasket bracket clips
There are two clips on each door. Start bracket removal
near one of the middle clips.
1) Pull gasket back to expose gasket bracket clip and
door frame.
2) Insert a flat tip screwdriver into seam between gasket
bracket and door frame and pry back until clips snaps
out.
3) Continue prying back along seam until all clips snap
out.
Gasket
Door
Bracket Clip
Frame
Figure 3
Flat Tip
Screwdriver
Gasket
Bracket Clip
Spring
Door
Frame
Correct Incorrect
Figure 5
4) Push in remaining two clips until you hear each snap
securely into place.
Note: Make sure that no part of gasket bracket edge
protrudes from beneath door frame edge.
3. Remove gasket
Pull gasket free from gasket channel on the three
remaining sides of door.
Gasket
Bracket
Figure 4
- 6 -
Insert gasket into channel
1) Snap gasket assembly into the door bracket.
<Inserting the Gasket Assembly into the Bracket Door>
2) Press gasket into channels on the three remaining
sides of door.
3. Replace door frame cover
Starting at top of cover and working down, snap cover
back into door.
3-5 DOOR ALIGNMENT
If the space between your doors is uneven, follow the
instructions below to align the doors:
1. With one hand, lift up the door you want to raise at
middle hinge.
2. With other hand, use pliers to insert snap ring as shown.
3. Insert additional snap rings until the doors are aligned.
(Three snap rings are provided with unit.)
- 7 -
Figure 6
Correct
Incorrect
Figure 7
Figure 8
Figure 9
3-6 FAN AND FAN MOTOR
1. Remove the freezer shelf. (If your refrigerator has an
icemaker, remove the icemaker first)
2. Remove the plastic guide for slides on left side by
unscrewing phillips head screws.
3. Remove the grille by removing one screw and pulling the
grille forward.
4. Remove the Fan Motor assembly by loosening 2 screws
and disassembling the shroud.
5. Pull out the fan and separate the Fan Motor and Bracket.
3-7 DEFROST CONTROL ASSEMBLY
Defrost Control assembly consists of Defrost Sensor and
FUSE–M.
The Defrost Sensor works to defrost automatically. It is
attached to the metal side of the Evaporator and senses its
temperature. At 72°C, it turns the Defrost Heater off.
Fuse-M is a safety device for preventing over-heating of
the Heater when defrosting.
1. Pull out the grille assembly. (Figure 12)
2. Separate the connector with the Defrost Control
assembly and replace the Defrost Control assembly
after cutting the Tie Wrap. (Figure 13)
3-8 LAMP
3-8-1 Refrigerator Compartment Lamp
1. Unplug the power cord from the outlet.
2. Remove refrigerator shelves.
3. Release the hooks on both ends of the lamp shield and
pull the shield downward to remove it.
4. Turn the lamp counterclockwise.
5. Assembly is the reverse of disassembly. Replacement
bulb must be the same specification as the original
(Max. 40 W2EA).
3-8-2 Freezer Compartment Lamp
1. Unplug refrigerator or disconnect power.
2. Reach behind light shield to remove bulb.
3. Replace bulb with a 40-watt appliance bulb.
4. Plug in refrigerator or reconnect power.
3-9 CONTROL BOX-REFRIGERATOR
1. First, remove all shelves in the refrigerator, than remove
the Refrigerator control Box by loosening 2 screws.
2. Remove the Refrigerator Control Box by pulling it
downward.
3. Disconnect the lead wire on the right position and
separate the lamp sockets.
3-10 MULTI DUCT
1. Remove the upper and
lower Caps by using a flat
screwdriver, and remove 2
screws. (Figure 17)
2. Disconnect the lead wire
on the bottom position.
- 8 -
GRILLE ASSEMBLY
Figure 12
DEFROST-CONTROL
ASSEMBLY
Figure 13
Figure 15
CONTROL BOX
COVER LAMP
Figure 16
Figure 17
GRILLE
FAN MOTOR
FAN
BRACKET
MOTOR
Figure 11
4-1 COMPRESSOR
4-1-1 Role
The compressor intakes low temperature and low pressure
gas from the evaporator of the refrigerator and compresses
this gas to high-temperature and high-pressure gas. It then
delivers the gas to the condenser.
4-1-2 Composition
The compressor includes overload protection. The PTC
starter and OLP (overload protector) are attached to the
outside of the compressor. Since the compressor is
manufactured to tolerances of 1 micron and is hermetically
sealed in a dust and moisture-free environment, use
extreme caution when repairing it.
4-1-3 Note for Usage
(1) Be careful not to allow over-voltage and over-current.
(2) If compressor is dropped or handled carelessly, poor
operation and noise may result.
(3) Use proper electric components appropriate to the
Particular Compressor in your product.
(4) Keep Compressor dry.
If the Compressor gets wet (in the rain or a damp
environment) and rust forms in the pin of the Hermetic
Terminal, poor operation and contact may result.
(5) When replacing the Compressor, be careful that dust,
humidity, and soldering flux don’t contaminate the inside
of the compressor. Contamination in the cylinder may
cause noise, improper operation or even cause it to
lock up.
4-2 PTC-STARTER
4-2-1 Composition of PTC-Starter
(1) PTC (Positive Temperature Coefficient) is a no-contact
semiconductor starting device which uses ceramic
material consisting of BaTiO
3.
(2) The higher the temperature is, the higher the resistance
value. These features are used as a starting device for
the Motor.
4-2-2 Role of PTC-Starter
(1) The PTC is attached to the Sealed Compressor and is
used for starting the Motor.
(2) The compressor is a single-phase induction motor.
Durign the starting operation, the PTC allows current
flow to both the start winding and main winding.
4-2-3 PTC-Applied Circuit Diagram
• Starting Method for the Motor
4-2-4 Motor Restarting and PTC Cooling
(1) It requires approximately 5 minutes for the pressure to
equalize before the compressor can restart.
(2) The PTC device generates heat during operation.
Therefore, it must be allowed to cool before the
compressor can restart.
4-2-5 Relation of PTC-Starter and OLP
(1) If the compressor attempts to restart before the PTC
device is cooled, the PTC device will allow current to
flow only to the main winding.
(2) The OLP will open because of the over current
condition. This same process will continue (3 to 5
times) when the compressor attempts to restart until
the PTC device has cooled. The correct OLP must be
properly attached to prevent damage to the
compressor.
Parts may appear physically identical but could have
different electrical ratings. Replace parts by part
number and model number. Using an incorrect part
could result in damage to the product, fire, injury, or
possibly death.
4-2-6 Note for Using the PTC-Starter
(1) Be careful not to allow over-voltage and over-current.
(2) Do not drop or handle carelessly.
(3) Keep away from any liquid.
If liquid such as oil or water enters the PTC,
PTC materials may fail due to breakdown of their
insulating capabilities.
(4) If the exterior of the PTC is damaged, the resistance
value may be altered. This can cause damage to the
compressor and result in a no-start or hard-to-start
condition.
(5) Always use the PTC designed for the compressor and
make sure it is properly attached to the compressor.
Parts may appear physically identical but could have
different electrical ratings. Replace parts by part
number and model number. Using an incorrect part
could result in damage to the product, fire, injury, or
possibly death.
4. ADJUSTMENT
- 9 -
PTC STARTER
SEALED
TERMINAL
COMPRESSOR
MOTOR
C
M
S
M
3
6
5
2
S
PTC
N
L1
OVERLOAD PROTECTOR
Resistance Starter Capacitor Running
Figure 17
4-3 OLP (OVERLOAD PROTECTOR)
4-3-1 Definition of OLP
(1) OLP (OVERLOAD PROTECTOR) is attached to the
Compressor and protects the Motor by opening the
circuit to the Motor if the temperature rises and
activating the bimetal spring in the OLP.
(2) When high current flows to the Compressor motor, the
Bimetal works by heating the heater inside the OLP,
and the OLP protects the Motor by cutting off the
current flowing to the Compressor Motor.
4-3-2 Role of the OLP
(1) The OLP is attached to the Sealed Compressor used
for the Refrigerator. It prevents the Motor Coil from
being started in the Compressor.
(2) For normal operation of the OLP, do not turn the Adjust
Screw of the OLP in any way.
4-4 TO REMOVE THE COVER PTC
1) Remove the Cover Back M/C.
(2) Disconnect two housing upper side of comp connected
in.
(3) Loosen two screws on comp base.
(4) Use a L-shaped flap tool to pry off the cover.
(5) Assembly in reverse order of disassembly.
- 10 -
Part
Customer part
number
Lot code/
date code
330 FBYY -S1 BOX98
12345678
Physical
termination
part number
Electrical
characteristics
part number
No. Name
Base, phenolic
(UL 94 V-0 rated)
Movable arm support, plated steel
Stationary contact support,
plated steel
Heater support, plated steel
Heater, resistance alloy
Disc, thermostatic alloy
Movable arm, spring temper
copper alloy
Contact, movable, silver on copper
Contact, stationary, silver on copper
Slug, plated steel
Cover, polyester
(UL 94 V-0 rated)
Pin connector, plated copper alloy
(To engage 2.33/2.66 mm dia. pin)
(OVERLOAD PROTECTOR cross section)
Figure 18
2
3
1
5. CIRCUIT DIAGRAM
LG Electronics
CIRCUIT DIAGRAM
PWB(PCB) ASSEMBLY,DISPLAY
BK
PR
GN
BL
4
3
5
6
F-FAN
STEPPING
MOTOR
RD
BO
1
2
PK
WH
YL
9
8
7
R-DOOR
PERCEPTION S/W
C
D
RT-SENSOR
PR
1
CON4
POWER
SUPPLY
CORD
CON1
SB
N
L
GN/YL
(GN)
MAIN FUSE
ICE MAKER PART
GN/YL
(GN)
SHEATH
WH
1
WH
1
HEATER,
CON3
WH
2
CON5
ICE SENSOR
WH
1
CON4
PWB (PCB) ASSEMBLY, ICE MAKER
* ICE MAKER CONFIGURATION
115-127V/50,60Hz
CON1
BL
2
BK
1
FUSE-M
POWER
(98 C)
S/W
220-240V/50,60Hz
FUSE-M
(98 C)
BK
BL
1
2
CON1
POWER
GY
2
11
SB
CON2
S/W
WH
BK
2
10
3
BN
WH
BL
BN
M
1
BK
YL
4
6
5
7
9
8
YL
YL
MOTOR
ICE MAKER
BL
2
CON1
* P.T.C START OPTION
LC COMP'
4
3
RD
BL
GN
RD
BO
12
13 6
10
8
11
9
7
1
CON5
2
3
PR
WH
PK
BK
5
7
4
PWB(PCB) ASSEMBLY, MAIN
4
3
1
(98 C)
S/W
RD
1
BL
BL
V
EG COMP'
4
2
2
BK
BK
I/MAKER
3
6
5
W/VALVE
5
6
7
RD
BN
CON2
RD
BN
CAPACITOR PART
PK
Cr
2
RD
Cs
4
5
3
6
BL
P.T.C STARTER
4
SB
3
SB
S
M
BL
2
SB
BK
COMP' EARTH
PART
6
BL
FUSE-M
BK
BK
1
2
BL
POWER
CON6
5
6
SB
8
1
OLP
YL
GY
GY
12
10
11
9
CON3
M
C-FAN
BK
GN
/YL
(GN)
*PLUG TYPE,ICE MAKER PART,CAPACITOR PART, P.T.C START OPTION
HEATER AND FUSE CONFIGURATION, ICE MAKER CONFIGURATION AND
COMP' EARTH PART ON CIRCUIT DIAGRAM ARE SUBJECT TO CHANGE
IN DIFFERENT LOCALITIES AND MODEL TYPE.
BN
BN
FUSE-M
(72 C)
RD
BN
FUSE-M
(72 C)
BL
1
BN
153
CON7
3
2
BL
BL
BN
HEATER,SHEATH
2
CON6
DOOR S/W-F
PK
1
2
PK
BO
3
4
BO
WH
5
6
WH
BL
7
BL
8
com
com
nc
nc
B
A
BO
com
nc
DOOR S/W-R
D
C
PR
F-LAMP
BL
BL
3854JK1007H
A
F-DOOR
PERCEPTION S/W
B
DEF-SENSOR
R-SENSOR
F-SENSOR
com
nc
R-LAMPS
DOOR HEATER
BL
BK:BLACK BN:BROWN RD:RED BO:BRIGHT ORANGE YL:YELLOW GN:GREEN BL:BLUE
WH:WHITE PK:PINK GY:GREY PR:PURPLE SB:SKY BLUE
- 11 -
6. TROUBLESHOOTING
- 12 -
6-1 COMPRESSOR AND ELECTRIC COMPONENTS
1
2
3
4
5
2
5
5
3
5
1
43
YES
NO
YES
The range of resistance is between 1~50? (ok)
Open or short
YES
YES
NO
NO
Power Source.
No Voltage.
(Rated Voltage
±10%)?
Replace OLP.
Reconnect.
Reference Page13.
Reference Page13.
Did
compressor
start?
Compressor
is OK
Replace the
compressor
Check connection
condition.
OLP disconnected?
Advise customer that
power supply needs to be
checked by an electrician.
Replace
Compressor.
Supply
voltage rating
with ±10%.
Applied voltage isn't
in acceptable range.
(115V ±10%)
Remove PTC-Starter
from Compressor and
measure voltage
between Terminal C of
Compressor and
Terminal 5 or 6 of PTC.
Check resistance
between M-C, S-C and
M-S in Motor
Compressor.
Check resistance of
two terminals in
PTC-Starter.
Check resistance of two
terminals in OLP.
Check the power supply
under load.
(Compressor attempting
to re-start after being off
for 5 minutes).
Check
resistance of
Motor
Compressor.
Check
resistance of
PTC-Starter.
Check OLP.
Check
starting state.
- 13 -
6-2 PTC AND OLP
65
Shows continuity
Open
Normal operation of
Compressor is
impossible or poor.
Separate PTC-Starter
from Compressor and
measure resistance
between No. 5 and 6
of PTC-Starter with a
Tester.
(Figure 19)
Separate OLP from
Compressor and check
resistance value
between two terminals
of OLP with a Tester.
(Figure 20)
Observation value is
115V/60Hz : 6.8 ±30%
The resistance value
is 0 (short) or
(open).
Check another
electric component.
Replace OLP.
Replace PTCStarter.
Figure 19
Figure 20
- 14 -
• Not cooling at all
•Poor cooling performance
Compressor
doesn't run.
Compressor runs
poorly.
Check starting
voltage.
Check for open short or
incorrect resistance readings
in the following components
a. Starting devices
b. OLP
c. Compressor coil
d.Wiring harness
Low voltage.
Short, open, or broken.
Poor contact
or shorted.
Coil open or shorted.
Poor contact
or shorted.
Poor or broken or
open contact.
Shorted.
Lack of capacity.
Replace
indicated component.
Advise customer that
the Power supply
needs to be checked
by an electrician.
Replace
indicated component.
Cause
Check voltage at
starting devices.
Check current flowing
in sub-coil of
Compressor.
Check rating of OLP.
Fan motor
doesn't run.
Heavy frost buildup on
EVAPORATOR.
Wire is open or
shorted.
Coil is shorted
or open.
Open.
Open.
Replace
Defrost Heater.
Replace
indicated component.
Replace
indicated component.
Check wiring circuit.
Check Fan Motor.
Check current flow in
the following
components:
Sensor
Fuse-M
Check current flow in
the Defrost Heater.
6-3 OTHER ELECTRICAL COMPONENTS
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