LG LRBP1031W User manual

CAUTION
BEFORE SERVICING THE UNIT,
READ THE SAFETY PRECAUTIONS IN THIS MANUAL.
MODEL: LRBP1031W
LRBP1031NI
REFRIGERATOR
SERVICE MANUAL
COLOR: EURO WHITE
Ref. No.
GR-349SQF
GR-349STQ
http://Biz.lgservice.com

SAFETY PRECAUTIONS....................................................................................................................................................... 2
SERVICING PRECAUTIONS.................................................................................................................................................. 3
SPECIFICATIONS................................................................................................................................................................... 4
PARTS IDENTIFICATION....................................................................................................................................................... 5
REPLACEMENT OF DOOR OPENING TYPE ....................................................................................................................... 6
DISASSEMBLY.................................................................................................................................................................... 7-8
DOOR................................................................................................................................................................................... 7
DOOR SWITCH.................................................................................................................................................................... 7
FAN AND FAN MOTOR........................................................................................................................................................ 7
DEFROST CONTROL ASSEMBLY...................................................................................................................................... 8
LAMP.................................................................................................................................................................................... 8
ADJUSTMENT................................................................................................................................................................... 9-10
COMPRESSOR.................................................................................................................................................................... 9
PTC-STARTER..................................................................................................................................................................... 9
OLP (OVERLOAD PROTECTOR) ..................................................................................................................................... 10
CIRCUIT DIAGRAM.............................................................................................................................................................. 10
TROUBLESHOOTING..................................................................................................................................................... 11-16
COMPRESSOR AND ELECTRIC COMPONENTS............................................................................................................ 11
PTC AND OLP.................................................................................................................................................................... 12
OTHER ELECTRIC COMPONENT.................................................................................................................................... 13
SERVICE DIAGNOSIS CHART.......................................................................................................................................... 14
REFRIGERATING CYCLE............................................................................................................................................ 15-16
MICOM FUNCTION & PCB CIRCUIT EXPLANATION................................................................................................... 17-33
EXPLODED VIEW .......................................................................................................................................................... 34-35
REPLACEMENT PARTS LIST............................................................................................................................................ 36-
Please read the following instructions before servicing your
refrigerator.
1. Check the set for electric leakage.
2. Unplug prior to servcing to prevent electric shock.
3. Whenever testing with power on, wear rubber gloves to
prevent electric shock.
4. If you use any kind of appliance, check regular current,
voltage, and capacity.
5. Don't touch metal products in the freezer with wet
hands. This may cause frostbite.
6. Prevent water from flowing onto electric elements in the
mechanical parts.
7. When standing up after having checked the lower
section of the refrigerator with the upper door open,
move with care to avoid hitting the upper door.
8. When tilting the set, remove any materials on the set,
especially the thin plates (ex. glass shelf or books.)
9. When servicing the evaporator, wear cotton gloves.
This is to prevent injuries from the sharp evaporator
fins.
10. Leave the disassembly of the refrigerating cycle to a
specialized service center. The gas inside the circuit
may pollute the environment.
SAFETY PRECAUTIONS
CONTENTS
- 2 -

Air Recharging in Compressor
Test the refrigeration by connecting it electrically before
refilling operation. It is necessary to ascertain the function
of the motor-compressor and identify the defects
immediately. If defects have been found, empty the old
system of possible R134a residue by breaking off the end
of the extension piece at its narrow point. (Figure 1)
Replace the filter and any damaged components. Unsolder
and pull off the piece remaining inside the service tube and
then attach an complete extension with male Hansen, and
solder it to the same tube again. (Figure 2)
It is necessary to execute the soldering operation with
valve open so that the fumes caused by oil residue can
come out freely without blowholes between two tubes
during the heating of the point to be soldered.
The extension fitted with the male Hansen is connected to
the female fitting of the vacuum pump tube. (Figure 3)
Air evacuating from the system begins as soon as the
pump starts. The refrigeration system must be kept under
vacuum until the reading on the low-pressure gauge
indicates vacuum (0 absolute, -1 atm., -760 mm hg) in any
case it is advisable to keep the pump running for about 30
minutes. (Figure 3)
In case that a considerable leakage occurs it will be
necessary to stop the vaccum pump and to add a small
quantity of Freon to the system, if vacuum should not be
obtained (pressure gauge can't fall to 1 atmosphere), start
the refrigeration unit and find the leakage with the special
leak-finder. When the defective soldering point is visible,
re-do it after opening the extension tube valve and
reestablishing the normal outside pressure inside the
group.
Because the melted alloy is sucked into the tubes and
blocks them, the pressure must be rebalanced when
vacuum is in the system in soldering. As soon as the
vacuum operation is over, add the quantity in grams of
R134a to the refrigeration system. Remember that every
system has an exact quantity of R134a with a tolerance of
±5 grams that can be added. (Figure 4)
Before performing this operation (if the vacuum pump and
refilling cylinder are connected), make sure that the valve
placed between the vacuum pump and the refilling tube are
closed in order to keep the Freon for addition to the system.
(Figure 5)
In addition, check the graduated scale on the cylinder for
the quantity of R134a to be added, for example, if we have
750 grams of Freon in the cylinder and must add 165
grams to the group, this amount will be reached when R-
134a has dropped to 585 grams, remembering that the
indicator shows a lower limit of meniscus. Do this after
choosing the scale corresponding to the gas pressure
different scales reported as the same gas pressure
indicated by the pressure gauge on the top of the column.
To make R134a flow into the system, open the valve
placed at the base of the cylinder and connected to the
filling tube. The amount of Freon cannot be added to the
system all at once because it may cause a blocking of
the motor-compressor. Therefore, proceed by adding the
original quantity of about 20-30 grams and close the valve
immediately.
The pressure rises and the motor compressor must start
sucking the gas and lowering the pressure again.
Regulate the valve again, in the safe way until reaching the
quantity of R134a established for the system being
charged. When the system is running, the suction pressure
must be stabilized between 0.30 to 0.6 atmosphere.
POINT TO BE
BROKEN CHARGE TUBE
EXTENSION
FEMALE
HANSEN
MALE HANSEN
SOLDERING POINTSERVICE TUBE EXTENSION
Figure 1 Figure 2
TO THE VACUUM
PUMP
PRESSURE
GAUGE
Figure 3
TO THE R134a CYLINDER
TO THE REFRIGERATION
SYSTEM
Figure 4
FILLING OR
CHARGE TUBE VALVE TO BE OPENED
WHEN REFILLING
VALVE TO BE CLOSED
AFTER VACUUM
TO THE VACUUM PUMP
TO THE REFRIGERATION
SYSTEM TO THE CHARGE
CYLINDER
Figure 5
SERVICING PRECAUTIONS
- 3 -

1. Ref. No: GR-349****
SPECIFICATIONS
- 4 -
ITEMS SPECIFICATIONS
DIMENSIONS (mm) 595(W)
X
626(D)
X
1710(H)
NET WEIGHT (kg) 69
COOLING SYSTEM Fan Cooling
REFRIGERATOR Knob Dial
FREEZER Button
Full Automatic
DEFROSTING SYSTEM Heater Defrost
DOOR FINISH Pre-Coated Metal
OUT CASE Painted Steel Sheet
INNER CASE ABS
INSULATION Polyurethane Foam
DEFROSTING DEVICE Heater, Sheath
REFRIGERANT R134a (150 g)
LUBRICATION OIL FREOL @ 22G (210 cc)
TEMPERATURE
CONTROL
ITEMS SPECIFICATIONS
Transparent Shelf (2 EA)
REFRIGERATOR Vegetable Container (2 EA)
COMPARTMENT
Vegetable Container Cover (1 EA)
Chilled Container (1 EA)
Dairy Pocket Cover (1 EA)
Egg Tray (1 EA)
DOOR POCKET Little Pocket (3 EA)
Bottle Pocket (1 EA)
FREEZER Tray Drawer (4 EA)
COMPARTMENT Ice Tray (1 EA)
COMPRESSOR PTC Starting Type
EVAPORATOR Fin Tube Type
CONDENSER Side & Wire Condenser
or Vinyl Coated Metal

NOTE : This is a basic model. The shape of refrigerator is subject to change.
PARTS IDENTIFICATION
- 5 -
Rotatable
Door Basket
(3)
Utility Corner
(movable)
Bottle Holder
2-liter Bottle
Door Basket
Leveling Screw
Egg Tray (1)
Freezer Temperature
Control
Removable
Glass Shelf (2)
Lamp
Multi-air Flow Duct
Fresh Meat Keeper
Refrigerator
Temperature Control
Vegetable Drawer
Used to keep fruits
and vegetables, etc.
fresh and crisp.
Ice Cube Tray
Freezer
Compartment
Removable
Base

1. PRECAUTION
1) Before reversing the door, you should remove food and
accessories like shelves or trays which are not fixed in
the refrigerator.
2) Use Torque Wrench or Spanner to fix or remove the
bolt.
3) Don't lay the refrigerator down in working with it, it will
cause a malfunction.
4) Be careful not to drop the door in disassembling or
assembling the freezer or the refrigerator door.
2. HOW TO REVERSE THE DOORS
1) Remove screw 2and remove Cover 1and move Cap
Cover 3. And, remove screw 4, Hinge-L 5, and
remove pin 6. Remove the Freezer Door , and move
the position of the cap 7. Move the position of bracket
door 8and screw 9.
2) Remove bolt Jand remove the Hinge-C
Kand the Fridge Door L. Move the
position of the cap M. Move the position of bracket
door Pand screw Q.
3) Move the position of Hinge-U pin N, and Cap, Top cover
OAssemble the Fridge Door L. Assemble Hinge-C K
and bolt J. Assemble F-Door . Assemble the Hinge-L
5and bolt 4. Assemble Low Cover 1and screw 2.
REPLACEMENT OF DOOR OPENING TYPE
- 6 -
7
2
3
1
21 4
6
5
8
9
14
15
12
11
5
4
21
10
2
1
12
13
10
11
16
17
21
21

1 DOOR
● Freezer Door
1) Loosen 2 screws and pull the Lower Cover.
2) Loosen hexagonal bolts fixing the lower hinge to the
body to remove the freezer door only.
3) Pull out the Door Gasket to remover from the
Door Foam Assembly, F.
●Refrigerator Door
1) Loosen hexagonal bolts fixing the center hinge
(Hinge,C) to the body to remove the refrigerator door
only.
2) Pull out the Door Gasket to remove from the
Door Foam Assembly, R.
2 DOOR SWITCH
1) Loosen four screws in upper part and disconnect top
cover.
2) Disconnect Lead Wire from switch.
3) Disengage hook behind the switch by pressing it with
hands.
3 REFRIGERATOR LAMP
1) Remove the Cover Lamp by pulling with a slotted type
driver.
2) Remove the lamp by turning.
Bolt
Lower Hinge
Figure 6
GASKET
Figure 7
Hinge, C
Bolt
Figure 8
Figure 9
DISASSEMBLY
- 7 -
Figure 10

4 FAN AND FAN MOTOR
1) Remove freezer drawers.
2) Remove two cap screws and loosen two screws in Grille Fan.
3) Pull out the Grille Fan and Shroud.
4) Disconnect the housing of lead wire.
5) Separate the Fan Assembly.
6) Losse 2 screw fixed to the Bracket.
7) Pull out Shroud to remove the Fan Motor Assembly.
8) Separate the Motor Bracket and Rubber.
5 DEFROST CONTROL ASSEMBLY
Defrost Control Assembly consists of Thermistor and Melting
Fuse. Thermistor functions to defrost automatically and it is
attached to metal side of the Evaporator and senses temperature.
Melting Fuse is a kind of safety device for preventing overheating
of the Heater when defrosting.
At the temperature of 72°C, it stops the emission of heat from the
Heater.
1) Pull out the Shroud after removing the Grille.
2) Separate the connector connected with the Defrost Control
Assembly and replace new one.
6 DAMPER CONTROL
1) Remove the Cover Lamp and loosen 2 screw.
2) Pull the Control Box and separate the lead wire housing.
3) Remove the Cover Lamp.
4) Separate the Insulation Multi Duct and Control Box.
5) Disassemble the Knob.
6) Separate the Damper Control and Control Box.
7) Separate the Damper Control and Resistor.
8) Disconnect the lead wire.
7 HEATER, SHEATH
In this refrigerator, Heater, Sheath is used for defrosting
heater. During heating, the temperature of heater rises
about 300~500°C. Therefore, be careful not to burn
yourself while servicing.
1) After removing the Grille and Shroud, separate the
Heater Sheath by disconnecting the connectors.
2) Exchanged Heater Sheath and connect the housing.
REFRIGERATOR ROOM LAMP
Heater Sheath
GUIDE FANFAN
SHROUD FAN MOTOR
GRILLE
Melting Fuse
Thermistor
Figure 13
Figure 14
Figure 11
Figure 12
- 8 -

1 COMPRESSOR
1) Role
The compressor intakes low temperature and low pressure
gas evaporated from evaporator of the refrigerator, and
condenses this gas to high temperature and high pressure
gas, and then plays delivering role to Condenser.
2) Composition
The Compressor is composed of compressor
apparatus compressing gas, compressor motor
moving compressor apparatus, and case protecting
compressor apparatus and motor. There are PTC-
Starter, and Over Load Protector (OLP) in the
Compressor outside. On the other hand, because the
Compressor consists of 1/1000mm processing
precision components and is sealed after production
in absence of dust or humidity, deal and repair with
care.
3) Note for Usage
(1) Be careful not to allow over-voltage and over-current.
(2) Do no strike.
If applying forcible power or strike (dropping or careless
dealing), poor operation and noise may occur.
(3) Use proper electric components appropriate to the
compressor.
(4) Note to Keep Compressor dry.
If compressor gets wet in the rain and rusts in the pin of
hermetic terminal, the result may be poor operation
from poor contact.
(5) Be careful that dust, humidity, and welding flux don't
flow in the compressor inside in replacing the
compressor. Dust, humidity, and flux due to welding
which inflows to cylinder may cause lockage and noise.
2 PTC-STARTER
1) Composition of PTC-Starter
(1) PTC (Positive Temperature Coefficient) is a no-contact
semiconductor starting device which uses ceramic
material. This material consists of BaTiO3.
(2) The higher the temperature is, the higher becomes the
resistance value. These features are used as the
starting device for the Motor.
2) Role of PTC-Starter
(1) PTC is attached to hermetic compressor used for
refrigerator, show case and starts motor.
(2) Compressor for household refrigerator applies to
single-phase induction Motor.
For normal operation of the single-phase induction
motor, in the starting operation current flows in both
main coil and sub-coil. After the starting is over, the
current in subcoil is cut off. The proper features of PTC
play all the above roles. So, PTC is used as a motor
starting device.
3) PTC-Applied Circuit Diagram
● According to Starting Method for the Motor
4) Motor Restarting and PTC Cooling
(1) For restarting after power off during normal compressor
motor operation, plug the power cord after 5 min. for
pressure balance of refrigerating cycle and PTC
cooling.
(2) During normal operation of the Compressor Motor, PTC
elements generate heat continuously. Therefore,
if PTC isn't cooled for a while after the power has been
shut off, the motor can't operate again.
5) Relation of PTC-Starter and OLP
(1) If the power is off during operation of compressor and
the power is on before the PTC is cooled, (instant shut-
off within 2 min. or reconnect a power plug due to
misconnecting), the PTC isn't cooled and a resistance
value grows. As a result, current can't flow to the sub-
coil and the motor can't operate and the OLP operates
by flowing over current in only in the main-coil.
(2) While the OLP repeats on and off operation about 3-5
times, PTC is cooled and compressor motor performs
normal operation.
If OLP doesn't operate when PTC is not cooled,
compressor motor is worn away and causes a short
curcuit and fire. Therefore, use a properly fixed OLP
without fail.
6) Note to Use PTC-Starter
(1) Be careful not to allow over-voltage and over-current.
(2) Do no strike.
Don't apply a forcible power or strike.
(3) Keep apart from any liquid.
If liquid such as oil or water enters the PTC,
PTC materials may break due to insulation breakdown
of the material itself.
(4) Don't change PTC at your convenience.
Don't disassemble PTC and mold. If the exterior of the
PTC-starter is damaged, resistance value is altered and
it may cause poor starting of the compressor motor.
(5) Use a properly repaired PTC.
PTC STARTER HERMETIC
TERMINAL
COMPRESSOR
MOTOR
C
M
SM
36
5
S
PTC
OVERLOAD PROTECTOR(O.L.P)
RSIR
Figure 19
ADJUSTMENT
- 9 -

3 OLP (OVER LOAD PROTECTOR)
1) Definition of OLP
(1) OLP (OVER LOAD PROTECTOR) is attached to the
hermetic compressor and protects the motor by cutting
off current in compressor motor in case of over-rising
temperature by Bimetal in the OLP.
(2) When over-voltage flows to Compressor motor, the
bimetal works by heating the heater inside the OLP,
and the OLP protects motor by cutting off current which
flows to the compressor motor.
2) Role of the OLP
(1) The OLP is attached to the hermetic compressor used
for the refrigerator and show case and prevents the
motor coil from being started in the compressor.
(2) Do not turn the adjust screw of the OLP in any way for
normal operation of the OLP.
(Composition and connection Diagram of OLP)
CIRCUIT DIAGRAM
CONTACTING
POINT COVER
BIMETAL
CONTACTING
POINT
HEATER
TERMINALS
ADJUST
SCREW
HEATER
BIMETAL
Figure 20
NOTE : This is a basic diagram and specifications vary in different localities.
- 10 -
C
N
L
3
4
6
5
2
S
BK
PK
RD
BLBLBL
BK
BL
RUNNING
fonctionnement
BL BLBL
RD
GY
BL
BK
PR
GN/YL
RT-SENSOR
RT-capteur
YL
YLBL
F-SENSOR
F-capteur
DOOR OPEN/ouverture portière
PERCEPTION/réception
DEF-SENSOR
DEF-capteur
BO
BO
BL
BL
GY
RD
1
2
3
4
5
6
GY PR BL YL RD BN
WH WHBO
BK GY BN
BK
STARTING
mise en route
SHEATH HEATER
manchon chauffage
M
C
PWB ASSY, MAIN
GROUPE PRINCIPAL PWB
DISPLAY CONTROL P.W.B
affichage de contrôle P.W.B
123456789
• THE PLUG TYPE,
CAPACITOR PART,
COMPRESSOR EARTH
PART ON CIRCUIT
DIAGRAM ARE SUBJECT
TO CHANGE IN DIFFERENT
LOCALITIES AND ACCORDANCE
WITH MODEL TYPE
• WHEN STARTING CAPACITOR
IS NOT USED, NO.3,4 OF PTC
START IS CONNECTED
INTERNALLY
BK:BLACK
YL:YELLOW
SB:SKY BLUE
BN:BROWN
GN:GREEN
PK:PINK
RD:RED
BL :BLUE
GN/YL:GREEN/YELLOW
BO:BRIGHT ORANGE
PR:PURPLE GY:GRAY
WH/BK:WHITE/BLACK
WH:WHITE
BL YL GY BN
BK
987654321
GY PR BL YL RD BN
WH WHBO
123456789
B
A
B
A
MM
•
Le type de prise, les pièces du
condensateur, les pièces de mise
à terre du compresseur sur le
diagramme de circuit sont sujets à
des changements dans différentes
localités et selon le type de modèle.
•
Quand le condensateur de mise
en route n'est pas utilisé, le n˚3.4
de mise en route PTC est branché
internement.
BK:noir
YL:jaune
SB:bleu ciel
BN:marron
GN:vert
PK:rose
RD:rouge
BL :bleu
GN/YL:vert/jaune
BO:orange brillant
PR:pourpre GY:gris
WH/BK:noir/blanc
WH:blanc
3854JD1040E
CIRCUIT DIAGRAM/DIAGRAMME DE CIRCUITCIRCUIT DIAGRAM/DIAGRAMME DE CIRCUIT
COMPRESSOR
compresseur
CAPACITOR PART
pièce condensateur P.T.C STARTER
starter P.T.C
COMP' EARTH
terre compresseur
OVER LOAD PROTECTOR
protection contre surcharge
DOOR S/W-R
portière S/W-R
LAMP-R
lampe-R
FUSE-M(72˚C)
fusible-M(72˚C)
FAN MOTOR
moteur ventilateur
COOLING FAN MOTOR
moteur ventilateur de
refroidissement
POWER SUPPLY CORD
Câble d'alimentation

1 COMPRESSOR AND ELECTRIC COMPONENTS
TROUBLESHOOTING (Mechanical Part)
- 11 -
1
2
3
4
5
2
5
5
3
4
5
5
1
43
YES
YES
YES
NO
YES
YES
NO
NO
5
YES
NO
YES
Power
Source. Remove the PTC-
Starter from the
Compressor and
measure the voltage
between Terminal C of
Compressor and
Terminals 5 or 6 of PTC.
No Voltage.
(Rating Voltage
±10%)?
Replace OLP.
Reconnect.
Replace
PTC-Starter.
Replace OLP.
O.K.
Check connection
condition.
OLP disconnected?
Advise the customer
to use a regular
Transformer.
Replace Compressor.
OLP works within
30 sec. in forcible
OLP operation by
turning instant power
on and off.
Components start in
the voltage of Rating
Voltage ±10% below.
Applied voltage isn't
in the range of Rating
Voltage ±10%.
Check the resistance
among M-C, S-C and
M-S in Motor
Compressor.
Check the resistance of
two terminals in PTC-
Starter.
Check if applying
a regular OLP.
Measure minimum
starting voltage after 5
min. for balancing cycle
pressure and cooling the
PTC.
Check the
resistance of
Motor
Compressor.
Check the
resistance of
PTC-Starter.
Check OLP.
Check
starting state.

2 PTC AND OLP
- 12 -
YES
NO
65
4
3
Normal operation of
Compressor is
impossible or poor.
Separate the PTC-Starter
from Compressor and
measure the resistance
between No. 5 and 6 (only
RSIR type) or No. 4 and 5 of
PTC-Starter with a Tester or
Whistone Bridge.
(Figure 21)
Separate the OLP from the
Compressor and check the
resistance value between
two terminals of OLP with
a Tester. (Figure 22)
Observation value is
220V/50Hz : 22Ω±30%
115V/60Hz : 6.8Ω±30%
240V/50Hz : 33Ω±30%
127, 220V/60Hz : 22Ω
±30%
The resistance value is 0
or serveral hundreds Ω.
The value is ∞.
Check another
electric components.
Replace OLP.
Check another
electric
components.
Replace
PTC-Starter.
Figure 21 Figure 22

3 OTHER ELECTRIC COMPONENTS
- 13 -
▼No Cooling.
Compressor
doesn't run.
Running state of
compressor is poor. Check starting
voltage.
Check if current flows to
the following
components.
a. Thermistor
b. Starting devices
c. OLP
d. Compressor coil
e. Circuit Parts
Low voltage.
Poor contacting.
Shorted or broken.
Poor contacting
or shorted.
Coil shorted.
Poor contacting
or shorted.
Poor contacting
and broken.
Shorted.
Lack of capacity.
Coil of motor
Compressor. Replace
the compressor.
Replace
each component.
Raise the voltage.
Replace
each component.
Cause.
Check if current flows
to starting devices.
Check current flowing
in sub-coil of
Compressor.
Check capacity of OLP.
The items described
above are normal.
▼ Cooling ability is poor
Fan motor
doesn't run.
Much frost are sticked
to the EVAPORATOR.
Poor contacting.
Coil is shorted.
Shorted.
Replace
the Heater Sheath
Replace
each component.
Replace
each component.
Check current flowing
in DOOR SWITCH.
Check current flowing in the
FAN MOTOR is stuck.
Check current flowing
of the following
components.
• THERMISTOR
• MELTING FUSE
Check current flowing
of the following
components.
• HEATER, SHEATH

4 SERVICE DIAGNOSIS CHART
COMPLAINT POINTS TO BE CHECKED REMEDY
Cooling is • Is the power cord unplugged from the outlet? • Plug in to the outlet.
impossible. • Check if the power switch is set to OFF. • Set the switch to ON.
• Check if the fuse of power switch is shorted. • Replace a regular fuse.
• Measure the voltage of power outlet. • If voltage is low, wire newly.
Cooling ability • Check if the set is placed close to wall. • Place the set with the space of about 10cm.
is poor. • Check if the set is placed close to stove, gas • Place the set apart from these heat
• cooker and direct rays. • appliances.
• Is the ambient temperature high or • Make the ambient temperature below.
• the room door closed?
• Check if put in is hot. • Put in foods after cooled down.
• Did you open the door of the set too often • Don't open the door too often and close
• or check if the door is closed up? • it firmly.
• Check if the Damper Control is set to cold-position. • Set the control to mid-position.
Foods in the • Is foods placed in cooling air outlet? • Place foods in high temperature section.
Refrigerator • (Front Part)
are frozen. • Check if the control is set to cold-position. • Set the control to mid-position.
• Is the ambient temperature below 5°C? • Set the control to warm-position.
Dew or ice • Is liquid food stored? • Seal up liquid foods with wrap.
forms in the • Check if put in is hot. • Put in foods after cooled down.
chamber of • Did you open the door of the set too • Don't open the door too often and close
the set. • often or check if the door is closed. • it firmly.
Dew forms • Check if ambient temperature and humidity • Wipe dew with a dry cloth. This occurrence
in the Exterior Case. of surroumcling air are high. • is solved naturally in low temperature and humidity.
• Is something in the door holding it open? • Rearrange items to close door.
Abnormal • Are the set positioned in a firm and even place? • Adjust the adjust screw and position
noise generates. • in the firm place.
• Are any unnecessary objects set • Remove the objects.
• in the back side of the set?
• Check if the Tray Drip is not firmly fixed. • Fix it firmly on the original position.
• Check if the cover of mechanical room • Place the cover at the original position.
• in below and front side is taken out.
To close the door • Check if the door packing is has something • Clean the door packing.
is not handy. • spilled on it.
• Is the set positioned in a firm and even place? • Position in the firm place and adjust the
• adjust screw.
• Is the refrigerator overloaded? • Keep foods not to reach the door.
Ice and foods • Check if the inside of the set is dirty. • Clean the inside of the set.
smell unpleasant. • Did you keep aromatic foods without wrapping? • Wrap aromatic foods.
• It smells of plastic. • The new products smells of plastic, but it is
• eliminated after 1-2 weeks.
●In addition to the items described left, refer to the followings to solve the complaint.
Check if dew forms in
the freezer.
Replace the
components of
defrosting circuit.
Check refrigerating
cycle.
Check the
damper control
Defrosting
is poor.
The cycle
is faulty. Repair the cycle.
Replace the
damper control
The operation of
the damper
control is poor.
- 14 -

5 REFRIGERATING CYCLE
▼Troubleshooting Chart
▼Leakage Detection
● Observe discharging point of refrigerant which may be in the oil discharging part in the compressor and hole of evaporator.
- 15 -
YES
YES
Whether compressor
runs or not.
Whether frost
forms or not in
evaporator.
Observe the discharged
amount of refrigerant.
Inject refrigerant to compressor
and check cooling operation.
Clogged by dust. Gas leakage.
Faulty
compressor.
Moisture clog.
Whether oil
leaks or not.
Frost formed normally
Normal amount
No or much amount
(Check the leakage point)
Frost formed normally
No frost
or forms
in inlet only
Check compressor
PARTIAL Freezer room and Low flowing sound of A little high • A little refrigerant
LEAKAGE refrigerator refrigerant is heard and more than • discharges.
don't cool frost forms in inlet only ambient • Normal cooling is possible
normally. temperature. • when injecting of refrigerant
• the regular amount.
WHOLE Freezer and Flowing sound of refrigerant Equal to ambient • No discharging of refrigerant.
LEAKAGE refrigerator is not heard and frost isn't temperature. • Normal cooling is possible
don't cool formed. • when injecting of refrigerant
normally. • the regular amount.
PARTIAL Freeze room and Flowing sound of refrigerant A little high • Normal discharging of
CLOG refrigerator is heard and frost forms more than • refrigerant.
don't cool in inlet only. ambient • The capillary tube is faulty.
normally. temperature.
WHOLE Freezer and Flowing sound of refrigerant Equal to ambient • Normal discharging of
CLOG refrigerator is not heard and frost isn't temperature. • Refrigerant.
don't cool. 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
temperature • capillary tube.
COMP- Freezer and Low flowing sound of A little higher • The pressure of high
RESSION refrigerator refrigerant is heard and than ambient • pressure part in
don't cool. frost forms in inlet only. temperature. • compressor is low.
NO COMP- No compressing Flowing sound of refrigerant Equal to ambient • No pressure of high pressure
RESSION operation. is not heard and no frost. temperature. • part in the compressor.
CAUSE TEMPERATURE
OF THE
COMPRESSOR REMARKS
STATE OF
THE SET STATE OF THE
EVAPORATOR
LEAKAGE
CLOGGED BY DUST
DEFECTIVE
COMPRESSION

NO. ITEMS CONTENTS AND SPECIFICATIONS REMARKS
WELDING (1) H 30
ROD (1) • Chemical Ingredients • Recommend H34 containing 34% Ag in the
(1) • Ag: 30%, Cu: 27%, Zn: 23%, Cd: 20% • Service Center.
(1) • Brazing Temperature: 710~840°C
(2) Bcup-2
(1) • Chemical Ingredients
(1) • Cu: About 93%
(1) • P: 6.8~7.5%
(1) • The rest: within 0.2%
(1) • Brazing Temperature: 735~840°C
FLUX (1) • Ingredients and how to make • Make amount for only one day. (1)
(1) ••Borax 30% • Holding period: 1 day
(1) ••Borax 35% • Close the cover of container to prevent dust
(1) • Fluoridation kalium: 35% • putting in the FLUX.
(1) • Water: 4% • Keep it in a stainless steel container.
(1) • Mix the above ingredients and boil until
(1) • they are transformed into liquid.
DRIER (1) Assemble the drier within 30min. • Don't keep the drier outdoors because
ASSEMBLY (1) after unpacking. • humidity damages to it.
(2) Keep the unpacked drier at the temperature
of 80~100°C.
VACUUM (1) When measuring with pirant Vacuum • Apply M/C Vacuum Gauge without fail.
(1 )gauge the charging M/C, vacuum • Perform vacuum operation until a proper
(1 )degree is within 1 Torr. • vacuum degree is built up.
(2) If the vacuum degree of the cycle inside is • If a proper vacuum degree isn't built up,•
(2) 10 Torr. below for low pressure and 20 Torr. • check the leakage from
(2) for high pressure, it says no vacuum • the Cycle Pipe line part and
(2) leakage state. • Quick Coupler Connecting part.
(3) Vacuum degree of vacuum pump must be
(3) 0.05 Torr. below after 5 min.
(4) Vacuum degree must be same to the
value described item (2) above for more than
20 min.
(1) The pressure of dry air must be more
than 12~16kg/cm2
(2) Temperature must be between
-20~and 70°C.
(3) Keep the pressure at 12~6kg/cm2also
(3) when substituting dry air for Nitrogen Gas.
NIPPLE (1) Check if gas leaks with soapy water. • Check if gas leaks from joint of the
AND (2) Replace Quick Coupler in case of leakage. • Coupler.
COUPLER
PIPE (1)• Put all Joint Pipes in a clean box and
(1)• cover tightly with the lid so that dust or
(1)• humidity is not inserted.
1
2
3
4
5
6
7
DRY AND
AIR
NITROGEN
GAS
▼General Control of Refrigerating Cycle
- 16 -

NOTCH
TEMP(˚C)
ROOM
Min Min/
Mid Mid Mid/
Max Max
-15 -16.5 -18 -19.5
FREEZER
VACATION FREEZE TEMP QUICK FREEZE
-22
This description is made for GR-349 & 389. Please refer to overall PCB circuits for other models.
1 FUNCTION EXPOSITION
1) FUNCTION
(1) The refrigerator starts from optimum condition when electric power is first on. The operation condition changes
Mid ➝Mid/Max ➝Max ➝Min ➝Min/Mid ➝Mid whenever you press the FREEZE TEMP button.
(2) It returns to Mid conditions if power off and on again.
MICOM FUNCTION & PCB CIRCUIT EXPLANATION
- 17 -
2) QUICK FREEZER
(1) This raises the freezing speed by operating the compressor continuously. Press the QUICK FREEZE button and
the QUICK FREEZE LED is displayed. Then after 3 hours' successive operation of compressor operation, the QUICK
FREEZING function will be released.
(2) Defrosting during the QUICK FREEZING operates as follows!
When the QUICK FREEZING time is below 90 minutes, defrost and then operate the QUICK FREEZING for the
remaining time. When the QUICK FREEZING time is over 90 minutes, defrost and then operate the QUICK FREEZING
for 2 hours
(3) If QUICK FREEZE button is pressed during defrosting, the QUICK FREEZE LED is lit. The QUICK FREEZING operates
for 3 hours after 7 minutes from the end of defrosting.
(4) If VACATION button is pressed during the QUICK FREEZING, the QUICK FREEZING LED function is released.
(5) If power is interrupted during QUICK FREEZING, the QUICK FREEZING function is released.
3) VACATION FUNCTION
(1) Function for Energy Saving. Press the VACATION button, and the VACATION LED is displayed and this function is
operated.
(2) Freezer Compartment is not kept by compressor at the notch displayed but at -13°C± differential.
(3) Defrosting and fan control are same as normal operation.
(4) If QUICK FREEZE button is pressed during the VACATION FUNCTION, VACATION FUNCTION is released.
(5) If power is interrupted during VACATION FUNCTION, the VACATION FUNCTION is released.

4) DOOR OPENING ALARM
(1) When the REFRIGERATOR DOOR is opened and isn't closed after 1 minute, the BUZZER sounds.
(2) At frist, BUZZER sounds three times at each intervals of 0.5 second, then makes a 0.5 second ON/OFF alarm three
times at intervals of 30 seconds.
(3) If the REFRIGERATOR door closed during ALARM, the ALARM cancels.
5) DISPLAY BUTTON RING
(1) If display function button (FREEZE TEMP, QUICK FREEZE, VACATION) of the front of the TOP COVER is pushed,
BUZZER rings with DING~ DONG~ (See the BUZZER OPERATION CHECK p.22)
6) DEFROSTING
(1) If the accumulated time for the operation of the COMPRESSOR is 7 hours, the DEFROSTING HEATER is started.
(2) The first defrosting is performed 4 hours (compressor ON) later since the power is on.
(3) If DEFROST SENSOR is over 7 °C during DEFROSTING, end the operation of DEFROSTING with DEFROSTING
HEATER paused, and after 7 minutes, the operation for the freezing is started.
If DEFROST SENSOR is not reach to 7 °C after 2 hours' operation of the defrosting heater, it indicates a defrosting
trouble. (See the TROUBLE REPRESENTING FUNCTION)
(4) If DEFROST SENSOR is short or open, defrosting is not performed.
7) ORDERLY OPERATION OF ELECTRIC PARTS
To avoid NOISE and DAMAGE, the items containing an electric parts such as compressor, DEFROSTING HEATER, and
FAN MOTOR operate in order as follows.
- 18 -
CLOSE OPEN CLOSE OPEN CLOSE
BUZZER
within
1 minute 1 minute 30
seconds 30
seconds
three
times three
times three
times
FREEZER
DOOR
OPERATION STATE OPERATION ORDER
WHEN DEFROST SENSOR
TEMPERATURE IS OVER
7°C. (WHEN PURCHASING
OR MOVING)
WHEN DEFROST SENSOR
TEMPERATURE IS BELOW
7°C. (WHEN POWER
FAILURE OR SERVICING)
WHEN RETURNING TO NORMAL
STATE FROM TEST MODE
POWER COMP FAN
ON ON ON
after 0.5 sec. after 0.5 sec.
All Elec. Parts COMP FAN
OFF ON ON
after 7 min . after 0.5 sec.
POWER DEFROSTING DEFROSTING
ON HEATER ON HEATER ON
after 0.5 sec. after 10 sec.
COMP FAN
ON ON
after 0.5 sec. after 0.5 sec.
WHEN PLUGGED AT FIRST

8) SELF-TEST
(1) Function to make service easy in case of occuring a trouble in the product.
(2) When a trouble occurs, the button is pushed, but the function doesn't operate.
(3) If a problem releases during the representation of trouble, a refrigerator performs the normal function (RESET).
(4) Error codes are displayed by FREEZE TEMP LEDs on TOP COVER. If ERROR occurs, the other LEDs except ERROR
CODE LEDs are all off.
ERROR CODE LEDs
THIS IS WHAT HAPPENS!
NO. ITEMS F1 F2 F3 F4 DESCRIPTION COMP FAN
DEFROST HEATER
1 FREEZER
FREEZER SENSOR open
SENSOR abnormal or short.
OO
2 DEFROST
DEFROST SENSOR open
SENSOR abnormal or short.
O O No defrosting
3
DEFROSTING
DEFROST HEATER,
FUNCTION TEMP. FUSE open or
is abnormal disconnection (Displayed
after at least 4 hours OOO
from the trouble's
occurring.)
4
RT-SENSOR NOTE 1)
Room Temperature
abnormal
SENSOR open or short OOO
- 19 -
VACATION FREEZE TEMP QUICK FREEZE
F1
ERROR CODE LEDs
F2 F3 F4
15 minutes On/
15 minutes Off
* NOTE 1) Press the QUICK FREEZE and FREEZE TEMP buttons together in normal operation,
get this result. If normal, LEDs on the TOP COVER is all on.
If abnormal, LEDs are all on except VACATION LED.
RT-SENSOR
:ON
O : OPERATE NORMAL :OFF

9) FUNCTION TEST
(1) Function to check the testing function of PCB and refrigerator and to find where the trouble.
(2) The test switch is on the MAIN PCB of refrigerator.
TEST FUNCTION is released and RESET after MAX. 2 hours, regardless of TEST MODE.
(3) If the buttons on TOP COVER is pushed during TEST MODE, Function is not operated and only BUZZER ring with
DING~ DONG~
(4) After the end of TEST MODE, pull out the power cord and plug it in again (RESET).
(5) If a ERROR occurs during the TEST MODE, TEST FUNCTION is released and DISPLAY LEDs represent ERROR
CODE.
(6) If the TEST swithch is pushed during ERROR CODE, TEST FUNCTION is not operated.
MODE OPERATION CONTENTS REMARKS
TEST 1 Press TEST button 1. COMPRESSOR OPERATES CONTINOUSLY.
once. 2. FAN OPERATES CONTINOUSLY.
3. DEFROSTING HEATER OFF
4. ALL DISPLAY LEDS ON.
TEST 2 Press TEST button 1. COMPRESSOR OFF. If DEFROST HEATER
once in the state of 2. FAN OFF. is over 7°C, it returns
TEST MODE 1. 3. DEFROST HEATER ON. to the NORMAL STATE.
4. ALL THE DISPLAY LEDS OFF EXCEPT
QUICK FREEZE AND VACATION LEDS.
NORMAL Press TEST button Return to the initial condition. Compressor starts
STATE once in the state of (RESET) after 7 minutes.
TEST MODE 2.
- 20 -
• LED Check Function : Press the QUICK FREEZE and FREEZE TEMP buttons at the same time. After 1 sec., all the
LEDs of the DISPLAY are ON simultaneously. Release the BUTTON to return to the previous
condition.
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