LG LFC20760SW User manual

CAUTION
BEFORE SERVICING THE UNIT,
READ THE SAFETY PRECAUTIONS IN THIS MANUAL.
REFRIGERATOR
SERVICE MANUAL
MODELS:
LFC20760SW /04
LFC20760SB /04
LFC20760ST /04

ECN (Engineering Change Number)
Rev.01
SVC Improvement opening door freezer (change design of rails)
Rev.02
Change Cover Lower, Case PCB and Rail
Rev.03
Change compressor & base compressor
Rev.04
Valve inclined in order to improve water house connection

CONTENTS
- 2 -
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.
SAFETY PRECAUTIONS
SAFETY PRECAUTIONS ..................................................................................................................
1. SPECIFICATIONS .........................................................................................................................
2. PARTS IDENTIFICATION ..............................................................................................................
3. DISASSEMBLY ..............................................................................................................................
3.1 Remove Refrigerator Door .......................................................................................................
3.2 Replace Refrigerator Door........................................................................................................
3.3 Remove Door Handle................................................................................................................
3.4 Door Gasket Removal...............................................................................................................
3.5 Door Gasker Replacement........................................................................................................
3.6 Door Alignment..........................................................................................................................
3.7 Pull Out Drawer.........................................................................................................................
3.8 Fan and fan motor ....................................................................................................................
3.9 Defrost control assembly...........................................................................................................
3.10 Lamp.......................................................................................................................................
3.11 Control Box Refrigerator.........................................................................................................
3.12 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 .........................................................................................................................
2
3
4
5
5
5
6
6
7
7
8
10
10
10
10
10
11
11
11
12
12
13
14
14
15
16
18
18
20
20
21
22
23
23
27
36
37
39
41
43

1. SPECIFICATIONS
- 3 -
LFC20760SW LFC20760SB LFC20760ST
Super White Black Stainless
PCM VCM Stainless
Yes (Plastic)
Yes (2) 40W/Blue
Yes
4 fix
Embo (normal)
Vista
ICE PLUS
3 left + 3 right
Anti-freezing Heater
Drier
Full Automatic
Heater Defrost
Cyclo, Pentane
MC57LAUM PTC Starting Type
4 Hours
7 - 40 Hours
Heater, Sheath
Water Tank Heater
FREEZER
Basket, Quantity
Tray meat
Lamp
Tray Drawer-F/U Yes (Full Width)
Tray Drawer-F/L Yes (Plastic)
No
No
Yes (1) 40W/Blue
Egg Bank
REFRIGERATOR
Case Material
Door Material
Handle Type
Display Graphic
Tray Drawer-F/L
Lamp
Shelf
Ice Tray & Bank
Basket, Quantity
Condenser
Lubricanting Oil
ID Ø0.75
Compressor
Fin Tube Type
Wire Condenser
Polyol Ester ISO 10 220 ± 10 cc
Cooling System
Rated Rating
Climate class
1B/(1EA)
MOLECULAR SIEVE XH-7
Defrost Cycle
Desfrosting Device
Evaporator
Capillary Tube
First Defrost
Temperature Control
Defrosting System
Insulation
MODELS
SPECIFICATIONS
Capacity
Refrigerant
Net Weight
Dimensions
GENERAL FEATURES
Color
R134a
Temperatel (T)
115V~ / 60Hz
MICOM control
29.8 (W) x 32.2 (D) x 68.4 (H) in
111 Kg
20 cuft
Fan Cooling

- 4 -
2. PARTS IDENTIFICATION
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.
*on some models
A
B
C
G
H
I
J
E
F
K
D
L
M
N
O
P
A
L
Digital Sensor Control Filter (Inside)*
Durabase
Divider
Egg Box *
Refrigerator Door Rack
Freezer Light
Pull out Drawer
B
C
D
F
E
G
H
I
J
K
M
N
O
P
Ice Tray *
Optibin Crisper
Keeps fruits and vegetable fresh and crisper
Chef Fresh / Snack Pan
Can Dispenser *
Shelves
Refrigerator Light
Custom cube Icemaker *
Dairy Bin
*

3-1 REMOVING REFRIGERATOR DOOR
3. DISASSEMBLY
- 5 -
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.
the inside up.
Right 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
Loosen ground screw (6).
Disconnect wire harness (5).
Left
Right
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).
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.

- 6 -
3-3 REMOVE DOOR HANDLE
Frame Cover
Handle
3-4 DOOR GASKET REMOVAL
1. Remove door frame cover
Starting at top of cover and working down, snap cover
out and away from door.
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.
3. Remove gasket
Pull gasket free from gasket channel on the three
remaining sides of door.
Gasket
Door Bracket Clip
Frame
Flat Tip
Screwdriver
Gasket
Bracket
Loosen the set screws with the 3/32” allen
wrench and remove the handle.
NOTE: If the handle mounting fasteners
need to be tightened or removes, use a 1/4”
allen wrench.

- 7 -
3-5 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.
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.
Gasket
Bracket Clip
Spring
Door
Frame Correct Incorrect
2. 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.
Correct
Incorrect
3) Replace door frame cover
Starting at top of cover and working down, snap cover
back into door.
3-6 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.)

3-7 PULL OUT DRAWER
(a) HOW TO REMOVE PULL OUT DRAWER
IMPORTANT: To avoid possible injury, product or
property damage, you will need two people to perform
the following instructions.
•Pull the drawer open to full lower extension. Remove
durabase by lifting it from rail system.
•Press both hangers with yours thumbs to lift it up.
Durabase
•Separate the left and right rail cover
screw
•Remove the screws of the rail on both sides.
•With both hands, hold both sides of the door and pull it
up to separate it from the rails.
•
CAUTION:When laying down the drawer, be careful
not to damage the floor or hurt your feet with the sharp
edges on hinge side.
CAUTION:
When removing drawer door, do not hold it
by the handle. Door could fall down and you may be
injured grasp door with both hands as pictured below
When removing.
Rail tabes
Door
supports
Push rails back into drawe cavity. With both hands, hold the
center of the bar and push it in so that both rails go back
simultaneously.
- 8 -

(b) HOW TO INSTALL PULL OUT DRAWER
IMPORTANT: To avoid possible injury, product or
property damage, you will need two people to perform
the following instructions.
•With both hands, hold the center of the bar and pull it
out to let both rails out to full extension simultaneously.
•Hook door supports into rail tabs.
•Lower door into final position and tighten the screws.
Rail tabes
Door Supports
Screws
Make sure you have a right rail cover for each side.
Right
Rail cover
Left
Rail cover
•Align the top holes of the rail cover with the top holes of
the door supports to assemble the rail cover.
Verify the hole’s assembly
•With the rails pulled out to full extension, insert the
durabase in the rail assembly.
Durabase
WARNING:To prevent accidental child and pet
entrapment or suffocation risk. DO NOT allow them to
play inside of drawer.
WARNING:DO NOT step or sit down on Freezer Door.
•
•
- 9 -

3-8 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.
3-9 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 1)
2. Separate the connector with the Defrost Control
assembly and replace the Defrost Control assembly
after cutting the Tie Wrap. (Figure 2)
3-10 LAMP
3-10-1 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).
3-10-2 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.
3-11 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.
3-12 MULTI DUCT
1. Remove the upper and
lower Caps by using a flat
screwdriver, and remove 2
screws. (Fig. 3)
2. Disconnect the lead wire
on the bottom position.
- 10 -
GRILLE ASSEMBLY
Fig. 1
DEFROST-CONTROL
ASSEMBLY
Fig. 2
CONTROL BOX
COVER LAMP
Fig. 3
GRILLE
FAN MOTOR
FAN
BRACKET
MOTOR

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 BaTiO3.
(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
- 11 -
PTC STARTER SEALED
TERMINAL
COMPRESSOR
MOTOR
C
M
SM
36
5
2
S
PTC
N
L1
OVERLOAD PROTECTOR
Resistance Starter Capacitor Running
C

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.
- 12 -
Part
Customer part
number
Lot code/
date code
330 FBYY -S1 BOX98
12345678
termination
part number
Electrical
characteristics
part number
No. Name
Base, phenolic
(UL 94 V-0 rated)
Movable arm support,
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)
2
3
1
Physical
plated steel.

5. CIRCUIT DIAGRAM
- 13 -
4
CON101
BK
MOTOR
1 9
C-FAN
BL
PK
STEPPING
6
BO
3
SB
5
RD
2 8
WH
F-FAN
PR
7
YL
PWB(PCB) ASSEMBLY,DISPLAY
1
BL
L1
BK
CON6
10
5
11
BL
FUSE1
RD
L
4
7
68
CON2
RD
CON1
CORD
GN/YL
BK
7
5
(GN)
POWER
YL
BN
PR
YL
8
BN
CON5
PK
WH
BO
96
BK
3 1 2
66
5
BN
YL
2
4
10
1
BL
11
BN
2 4
RD
5
9
BL
SB
N
7
SB
SUPPLY
3
SB
3
BL
SB
10
BN
BL
6
CON4
BK
YL
21
WH
8 9
PR
743
RD
CON7
GY
CON8
5
BO
1
1
R-DOOR
DEF-SENSOR
BPERCEPTION S/W
GY
F-DOOR
4
PERCEPTION S/W
PK
GY
4
A
RT-SENSOR
2
D
BO
3
BN
C
3
2PK
BN
BL
1
BL
SBSB
BN
2
13
CON3
32
SB
BN
7
BL
F-SENSOR
6
BL
WH
R-SENSOR
8
WH
5
CON4
GN/YL
CON2
M
HEATER,
BK
WH
ICE SENSOR
1
WH
ICE MAKER
ICE MAKER PART
2
2
WH
WH
MOTOR
1
SHEATH
CON1
1
CON5
CON3
(GN)
WH
1
(98 C)
FUSE-M
I/MAKER
W/VALVE
BK
V
S/W
Cr
RD
PK
22
CAPACITOR PARTCAPACITOR PART
CON6
1
BL
2
1
RD
BK
55
66
44
33
PTC STARTER
Cs
BL
COMP' ACCESSORIES
POWER
PK:PINKYL:YELLOW
BK:BLACK
GN:GREEN
BN:BROWN
PWB (PCB) ASSEMBLY, ICE MAKER
WH:WHITE
BL
FUSE-M
BL
BA
HEATER,SHEATH
BO
RD
(72 C)
nc
BK
OLP
/YL
SGN
PARTPART
SGN
/YL
M
COMP' EARTHCOMP' EARTH
(GN)(GN)
BL
PR
F-LAMP
nc
R-LAMPS
DC
nc
PR:PURPLE
BO:BRIGHT ORANGE
MEZ48108408
BL:BLUE
RD:RED
nc
SB:SKY BLUE
GY:GREY
SB
com
4
com
DOOR S/W-R
DOOR S/W-F
com
PWB(PCB) ASSEMBLY, MAIN
com
4
EG COMP'
46
3
2
5
MC,MQ COMP'
* P.T.C START OPTION
3256
COMP' ACCESSORIES ON CIRCUIT DIAGRAM ARE SUBJECT
*PLUG TYPE, ICE MAKER PART, CAPACITOR PART, P.T.C
START OPTION, DOOR HEATER, RT-SENSOR, THERMOSTAT,
DOOR S/W-R QTY. (1 OR 2), COMP' EARTH PART AND
TO CHANGE IN DIFFERENT LOCALITIES AND MODEL TYPE.
N
BL
Cr
PTC
COMBO KIT(PTC+OLP)
BK
L
OLP
* ALTERNATIVE COMP' ACCESSORIES
THERMOSTAT
FRENCH DOOR HEATER
CIRCUIT DIAGRAM

6. TROUBLESHOOTING
- 14 -
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
Did
compressor Compressor
is OK
Replace the
compressor
Check connection
condition.
Advise customer that
power supply needs to
be checked by an
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 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
PTC-Starter.
Check OLP.
Check
starting state.
Check resistance
of motor
compressor.
Check the resistance
between M-C, S-C and
M-S in motor compressor. Replace
compressor
Check
resistance of
motor
compressor.
electrician.
At normal temperature
6.8 +20: OK?
If power conducts: OK
If not: NG
Reconnect.
Replace OLP.

- 15 -
6-2 PTC AND OLP
65
Shows continuity
Open
Separate PTC-Starter
from Compressor and
measure resistance
between No. 5 and 6
of PTC-Starter with a
Tester.
(Figure 1)
Observation value is
115V/60Hz : 6.8?±20%
The resistance value
is 0 ?(short) or
(open).
Check another
electric component.
Replace OLP.
Replace PTC-
Starter.
Figure 1 Figure 2
Normal operation of
compressor is impossible
or poor.
Separate OLP from
compressor and check
resistance value between
two terminals of OLP whit a
tester.
(Figure 2)
?

- 16 -
• 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

6-4 SERVICE DIAGNOSIS CHART
- 17 -
COMPLAINT POINTS TO BE CHECKED REMEDY
•Other possible problems:
Check if frost forms in
the freezer.
Check Components
of the defrosting
circuit.
Check the
refrigeration system.
Check the
Thermistor.
Not
defrosting
The system
is faulty. Perform sealed
system repair.
Replace the
Thermistor.
The operation of
the Thermistor is
incorrect.
No Cooling.
Cools poorly.
Food in the
Refrigerator
is frozen.
Condensation or ice
forms inside
the unit.
Condensation forms
in the Exterior Case.
There is abnormal
noise.
Door does not
close well.
Ice and foods
smell unpleasant.
•
• Check if the power switch is set to OFF.
•
Check if the fuse of the power switch is shorted.
• Measure the voltage of the power outlet.
• Check if the unit is placed too close to the wall.
• Check if the unit is placed too close to the stove,
gas cooker, or in direct sunlight.
• Is the ambient temperature too high or
• Check if food put in the refrigerator is hot.
• Did you open the door of the unit too often
• Check if the Control is set to Warm position.
•
• Check if the control is set to colder position.
• Is the ambient temperature below 5º
•
• Check if food put in the refrigerator is hot.
• Did you open the door of the unit too
• Check if the ambient temperature and humidity
of the surrounding air are high.
•
•
• Are any unnecessary objects placed
• Check if the Drip Tray is not firmly fixed.
• Check if the cover of the compressor enclosure
in the lower front side is taken out.
• Check if the door gasket is dirty with
an item like juice.
•
•
• Check if the inside of the unit is dirty.
•
• The unit smells of plastic.
• Plug into the outlet.
• Set the switch to ON.
• Replace the fuse.
• If the voltage is low, correct the wiring.
• Place the unit about 4 inches (10 cm) from the wall.
• Place the unit away from these heat sources.
• Lower the ambient temperature.
• Put in foods after they have cooled down.
• Don't open the door too often and close
it firmly.
• Set the control to Recommended position.
• Place foods in the high-temperature section.
(front part)
• Set the control to Recommended position.
• Set the control to Warm position.
• Seal liquid foods with wrap.
• Put in foods after they have cooled down.
• Don't open the door too often and close
it firmly.
• Wipe moisture with a dry cloth. It will disappear
in low temperature and humidity.
• Fill up the gap.
• Adjust the Leveling Screw, and position the
refrigerator in a firm place.
• Remove the objects.
• Fix the Drip Tray firmly in the original position.
• Place the cover in its original position.
• Clean the door gasket.
• Position in a firm place and level the
Leveling Screw.
• Make sure food stored in shelves does not prevent
the door from closing.
• Clean the inside of the unit.
• Wrap foods that have a strong odor.
• New products smell of plastic, but this
will go away after 1-2 weeks.

6-5 REFRIGERATION CYCLE
- 18 -
•Troubleshooting Chart
PARTIAL Freezer Low flowing sound of A little higher • Refrigerant level is low due
LEAKAGE compartment and Refrigerant is heard and than ambient to a leak.
Refrigerator don't frost forms in inlet only. temperature. • Normal cooling is possible by
cool normally. restoring the normal amount of
refrigerant and repairing the leak.
COMPLETE Freezer Flowing sound of refrigerant Equal to ambient • No discharging of Refrigerant.
LEAKAGE compartment and is not heard and frost isn't temperature. • Normal cooling is possible by
Refrigerator don't formed. restoring the normal amount of
cool normally.
refrigerant and repairing the leak.
PARTIAL Freezer Flowing sound of refrigerant A little higher • Normal discharging of the
CLOG compartment and is heard and frost forms than ambient refrigerant.
Refrigerator don't in inlet only. temperature. • The capillary tube is faulty.
cool normally.
WHOLE
Freezer
Flowing sound of refrigerant Equal to ambient • Normal discharging of the
CLOG
compartment and
is not heard and frost isn't temperature. Refrigerant.
formed.
MOISTURE Cooling operation Flowing sound of refrigerant Lower than • Cooling operation restarts
CLOG stops periodically. is not heard and frost melts. ambient when heating the inlet of the
temperature. capillary tube.
COMP- Freezer and Low flowing sound of A little higher • Low pressure at high side
RESSION Refrigerator refrigerant is heard and than ambient of compressor due to low
don't cool. frost forms in inlet only. temperature. refrigerant level.
NO COMP- No compressing Flowing sound of refrigerant Equal to ambient • No pressure in the high
RESSION operation. is not heard and there is temperature. pressure part of the
no frost. compressor.
CAUSE
TEMPERATURE
OF THE
COMPRESSOR
REMARKS
STATE OF
THE UNIT
STATE OF THE
EVAPORATOR
LEAKAGE
CLOGGED BY DUST
DEFECTIVE
COMPRESSION
Refrigerator don t
cool.
'

6-5-1 Sealed System Diagnosis
- 19 -
“Not Cooling” Complaint
All components operating, No airflow problems, Not frosted up as a defrost problem
problem has been isolated to sealed system area
Frost
Pattern?
Equalization
Test
Partial
Very Fast
Inefficient
Compressor
Partial
Restriction
Complete
Restriction
Equalization
Test
Condenser
Temperature
None
Very Fast
Very SlowVery Slow
Hotter than Normal
Air/Low Side
Leak Loss of Change
Compressor Not
Pumping
Cap Tube
Sound
Room Temperature
Trace of Oil
Undercharge
Leak
Yes
No
Faint
Fast
None to Weak
(The equalization test is trying to restart a compressor using a start kit after it has been operating.)
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