LG LRBP1031xx Service 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 R134a 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)X626(D)X1710(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 2 and remove Cover 1 and 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 8 and screw 9.

2) Remove bolt J and remove the Hinge-C K and the Fridge Door L. Move the position of the cap M. Move the position of bracket door P and screw Q.

3) Move the position of Hinge-U pin N, and Cap, Top cover O Assemble the Fridge Door L. Assemble Hinge-C K and bolt J. Assemble F-Door . Assemble the Hinge-L 5 and bolt 4. Assemble Low Cover 1 and screw 2.

REPLACEMENT OF DOOR OPENING TYPE

- 6 -

8 9

16 17

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

Figure 13

Figure 14

Figure 11

Figure 12

- 8 -

SHROUD

FAN MOTOR

GUIDE FAN

FAN

GRILLE

Melting Fuse

Thermistor

Heater Sheath

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 PTCStarter, 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 BaTiO

(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 shutoff 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 subcoil 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

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

BLBLBL

RUNNING

fonctionnement

BL BLBL

GN/YL

RT-SENSOR RT-capteur

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

STARTING

mise en route

SHEATH HEATER

manchon chauffage

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

987654321

GY PR BL YL RD BN

WH WHBO

123456789

A B

•

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

fusible-M(72

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 -

4 5

YES

Power Source.

Remove the PTCStarter 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 PTCStarter.

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.

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