http://biz.lgservice.

com

REFRIGERATOR
SERVICE MANUAL
CAUTION
BEFORE SERVICING THE UNIT, READ THE "SAFETY
PRECAUTIONS" IN THIS MANUAL.

Ref. No.
GN-U262RLC/K
GN-U292RLC/K
GN-U262RVC/K
GN-U292RVC/K

MODEL: GN-U262
GN-U292
CONTENTS

SAFETY PRECAUTIONS ....................................................................................................................................................... 2

SERVICING PRECAUTIONS.................................................................................................................................................. 3
SPECIFICATIONS................................................................................................................................................................... 4
PARTS IDENTIFICATION ....................................................................................................................................................... 5
DISASSEMBLY.................................................................................................................................................................... 6-7
DOOR................................................................................................................................................................................... 6
DOOR SWITCH.................................................................................................................................................................... 6
FAN AND FAN MOTOR........................................................................................................................................................ 6
DEF' CONTROL ASM .......................................................................................................................................................... 7
REFRIGERATOR ROOM LAMP .......................................................................................................................................... 7
CONTROL BOX-R................................................................................................................................................................ 7
REPLACEMENT OF DOOR OPENING TYPE...................................................................................................................8-9
ADJUSTMENT................................................................................................................................................................. 10-11
COMPRESSOR.................................................................................................................................................................. 10
PTC-STARTER................................................................................................................................................................... 10
OLP (OVER LOAD PROTECTOR)..................................................................................................................................... 11
CIRCUIT DIAGRAM.............................................................................................................................................................. 11
TROUBLESHOOTING..................................................................................................................................................... 12-17
COMPRESSOR AND ELECTRIC COMPONENTS ........................................................................................................... 12
PTC AND OLP.................................................................................................................................................................... 13
ANOTHER ELECTRIC COMPONENT............................................................................................................................... 14
SERVICE DIAGNOSIS CHART.......................................................................................................................................... 15
REFRIGERATING CYCLE ............................................................................................................................................ 16-17
DESCRIPTION OF FUNCTION & CIRCUIT OF MICOM .................................................................................................18-34
EXPLODED VIEW ........................................................................................................................................................... 35-37
REPLACEMENT PARTS LIST ......................................................................................................................................... 38-41

SAFETY PRECAUTIONS
Please read the followings before servicing your refrigerator.
1. Check if an electric leakage occurs in the set. 7. When you stand up during observing the lower part
2. To prevent electric shock, unplug prior to servicing. with the upper door open, move with care to prevent
head wound which may happen by hitting the upper
3. In case of testing with power on, wear rubber gloves to
door.
prevent electric shock.
8. When sloping the set, remove any materials on the set,
4. If you use any appliances, check regular current, voltage
especially thin plate type. (ex.: glass shelf or books.)
and capacity.
9. When servicing evaporator part, wear cotton gloves
5. Don't touch metal products in cold freezer with wet hand.
without fail. It is to prevent wound by sharp fin of
It may cause frostbite.
evaporator.
6. Prevent water flowing to electric elements in mechanical
10. Leave a breakage of refrigerating cycle to a heavy
parts.
service center. The gas in cycle inside may soil
ambient air.

-2-
SERVICING PRECAUTIONS
Air Recharging in Compressor vacuum operation is over, add the quantity in grams of R-
Test the refrigeration by connecting it electrically before 134a to the refrigerant system. Remember that every
refilling operation. It is necessary to ascertain the function system has an exact quantity of R-134a with a tolerance of
of the motor-compressor and identify the defects ±5 grams that can be added. (Figure 4)
immediately. If the defects have been found, empty the old
system of eventual R-134a 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 extension completely with male Hansen and
last, solder it to the same tube again. (Figure 2)

CHARGE TUBE FEMALE TO THE R-134a CYLINDER

POINT TO BE BROKEN
EXTENSION HANSEN

MALE HANSEN TO THE REFRIGERATION

SYSTEM
Figure 4

SERVICE TUBE EXTENSION SOLDERING POINT

Figure 1 Figure 2 Before performing this operation (if the vacuum pump and
refilling cylinder are connected), make sure that the valve
placed between the vacuum pump and refilling tube are
It is necessary to execute the soldering operation with closed to keep the Freon for adding to the system. (Figure 5)
valve open so that the fumes caused by oil residue can
come out freely without blowholes between two tubes FILLING OR VALVE TO BE OPENED
during heating the point to be soldered. CHARGE TUBE WHEN REFILLING
The extension fitted with the male Hansen is connected to
the female fitting of the vacuum pump tube. (Figure 3)
TO THE REFRIGERATION TO THE CHARGE
SYSTEM CYLINDER

VALVE TO BE CLOSED
AFTER VACUUM

TO THE TO THE
VACUUM VACUUM Figure 5
PUMP PUMP

PRESSURE In addition, check the graduated scale on the cylinder for

GAUGE
the quantity of R-134a to be added, for example, if we have
Figure 3 750 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
Air evacuating from the system begins so soon as the indicator shows a lower limit of meniscus. Do this after
pump starts. The refrigeration system must be kept under choosing the scale corresponding to the gas pressure
vacuum until the reading on the low-pressure gauge different scales reported as the same gas pressure
indicates vacuum (0 absolute, -1 atm., -760 mm hg) in any indicated by the pressure gauge on the top of the column.
case it is advisable to keep the pump running for about 30
To make R-134a flow into the system, open the valve
minutes. (Figure 3)
placed at the base of the cylinder and connected to the
In case that a considerable leakage occurs and to stop the filling tube. The amount of Freon cannot be added to the
vacuum pump will be necessary and add a small quantity system all at once because it may cause a blocking of
of Freon to the system, if vacuum should not be obtained motor-compressor. Therefore, proceed by adding original
(pressure gauge can't fall to 1 atmosphere), start the quantity of about 20-30 grams and close the valve
refrigeration unit and find the leakage with the special leak- immediately.
finder. When the defective soldering point is visible, re-do it The pressure rises and the motor-compressor must start,
after opening the extension tube valve and reestablishing sucking the gas and making the pressure go down again.
the normal outside pressure inside the group. Regulate the valve again, maintaining the same manner
Because the melted alloy is sucked into the tubes and until reaching to the quantity of R-134a established for the
block them, the pressure must be rebalanced when system being charged. When the system is running, the
vacuum is in the system in soldering. As soon as the suction pressure must be stabilized between 0.30 to 0.6
atmosphere.
-3-
1. SPECIFICATIONS
1-1 GR-262/GN-262/GN-U262

ITEMS SPECIFICATIONS ITEMS SPECIFICATIONS

FREEZER 61 FREEZER 1 EA
SHELF
NET CAPACITY REFRIGERATOR 158 REFRIGERATOR 2 EA
( l)
TOTAL 219 VEGETABLE TRAY Drawer Type
GR-262S(V)Q
GN-262S(V)C/K 540(W) x 610(D) x 1530(H) EGG TRAY 1 Piece
DIMENSIONS
(mm) GN-U262RL(V)C/K ICE TRAY 1 Piece (*2)
GR-262Q(V)C 540(W) x 628(D) x 1530(H)
GN-262Q(V)C ICE BANK 1 Piece
NET WEIGHT (kg) 46
COMPRESSOR P.T.C Starting Type
COOLING SYSTEM Fan Cooling
EVAPORATOR Fin Tube Type
TEMPERATURE FREEZER Knob Shutter
CONDENSER Pipe On Sheet Type
CONTROL REFRIERATOR Micom Control
REFRIGERANT R134a (120g)
Full Automatic
DEFROSTING SYSTEM LUBRICATING OIL FREOL α 22G (210cc)
Heater Defrost
DEFROSTING DEVICE L-CORD, PLATE HEATER
OUT CASE Coated Steel Sheet
(*) : OPTION
INNER CASE ABS

INSULATION Polyurethane Foam

1-2 GR-292/GN-292/GN-U292

ITEMS SPECIFICATIONS ITEMS SPECIFICATIONS

FREEZER 61 FREEZER 1 EA
SHELF
NET CAPACITY REFRIGERATOR 176 REFRIGERATOR 2 EA
( l)
TOTAL 237 VEGETABLE TRAY Drawer Type
GR-292S(V)Q
GN-292S(V)C/K 540(W) x 610(D) x 1620(H) EGG TRAY 1 Piece
DIMENSIONS
(mm) GN-U292RL(V)C/K ICE TRAY 1 Piece (*2)
GR-292Q(V)C 540(W) x 628(D) x 1620(H)
GN-292Q(V)C ICE BANK 1 Piece
NET WEIGHT (kg) 49
COMPRESSOR P.T.C Starting Type
COOLING SYSTEM Fan Cooling
EVAPORATOR Fin Tube Type
TEMPERATURE FREEZER Knob Shutter
CONDENSER Pipe On Sheet Type
CONTROL REFRIERATOR Micom Control
REFRIGERANT R134a (120g)
Full Automatic
DEFROSTING SYSTEM LUBRICATING OIL FREOL α 22G (210cc)
Heater Defrost
DEFROSTING DEVICE L-CORD, PLATE HEATER
OUT CASE Coated Steel Sheet
(*) : OPTION
INNER CASE ABS

INSULATION Polyurethane Foam

-4-
2. PARTS IDENTIFICATION

FREEZER
COMPARTMENT Cap Cover
(Optional)
Twisting Ice Serve (Optional)
or General Type Ice Making Upper Hinge

Freezer Temperature Freezer Door Rack

Control Knob
Cap Hinge
(Optional)

REFRIGERATOR
COMPARTMENT
Egg Storage Rack
Chilled Compartment

Refrigerator Temperature
Electronic Control

Lamp (GR-292 only)

Deodorizer
(Optional)
Vitamin Kit
(Optional)
Refrigerator Door Rack
Vegetable Drawer
Used to keep fruits
and vegetables, etc.
fresh and crisp.

Leveling Screws

NOTE: This is a basic model. The shape of refrigerator is subject to change.

-5-
3. DISASSEMBLY
3-1 DOOR 3-2 DOOR SWITCH
 Freezer Door 1. To remove the door switch, pull out it with a 'Ñ' type
1. Remove the hinge upper by loosen the screw driver as shown in (figure 9).
2. Lift the freezer door 2. Disconnect the lead wire from the switch.

Hinge Upper
Screw

Figure 9

Figure 6 3-3 THERMISTOR

1. Remove the Cover Lamp-R by the use of 'ÐÐÐ' type driver
3. Pull out the door gasket to remove from the door foam inserting in the low holes of the cover.
Ass'y. 2. Loose 2 screw.
3. Pull the Control Box-R.
GASKET 4. Disconnect the Housing of lead wire.
5. Separate the INSU'Multi Duct and Control Box-R.
6. Separate the Thermistor and Control Box-R.
7. Separate the Thermistor and Display PCB.

INSU'MULTI DUCT

DISPLAY PCB

THERMISTOR
Figure 7
CONT' BOX-R

‫ﯸ‬ Refrigerator Door

COVER LAMP-R
1. Loosen hexagonal bolts fixing the lower hinge to the
body to remove the refrigerator door only.

Figure 10

3.4 FAN AND FAN MOTOR

LOWER HINGE 1. Remove the freezer shelf.
2. Separate the twist by pulling right.
3. Loose 1 screw.
4. Pull out the Grille Fan and Shroud-F.

Figure 8
BOLT

2. Pull out the door gasket to remove from the door foam
Ass'y.

SCREW

Figure 11

-6-
5. Disconnect the housing of lead wire. 3-6 REFRIGERATOR ROOM LAMP
6. Separate the Fan Assy. 1. Remove the cover lamp-R by pulling with a 'ÐÐÐ'type
7. Loose 2 screw fixed to the Bracket. driver.
8. Pull out Shroud-F remove the Fan Motor Assy. 2. Remove the lamp-R by turning.
9. Separate the Motor Bracket and Rubber.
REFRIGERATOR ROOM LAMP
FAN MOTOR
SHROUD-F

BRACKET

FAN

Figure 17
GRILLE FAN Figure 12

3-7 CONTROL BOX-R

3-5 DEF' CONTROL ASM 1. Remove the Cover Lamp-R.
Def control ASM consists of Defrost Sensor and FUSEÐM.
Defrost Sensor functions to defrost automatically and it is
attached to the Evaporator and the metal side of the case
CONTROL BOX-R
senses Temp.
Fuse-M is a kind of safety device for preventing over-
heating of the Heater when defrosting.
o
At the temperature of 72 C, it stops the emission of TEMP
COVER LAMP
from the Defrost Heater.
1. Pull out the shroud-F after removing the Grille Fan.
(Figure 13)
2. Separate the connectors connected with the Def Control
ASM and replace the Def Control ASM after cutting the
Tie Wrap. (Figure 14)
Figure 18
SHROUD-F
DEF CONTROL ASM

2. Loosen 2 screws.
3. Full the Control Box-R.
4. Separate the lead wire Housing.

Figure 13 Figure 14

-7-
 - Converting Door is Optional
3-8 REPLACEMENT OF DOOR OPENING TYPE
鈸 Precaution
1. Before replacing the door opening type, first of all, you should take out
foodstuffs and accessories like shelves or trays, and so on which are not fixed
in the refrigerator.
2. Use the '+' Driver, Bolt Driver, Torque Wrench or Spanner to fix or remove the
bolt.
3. Be careful not to fall down the refrigerator in disassembling or assembling the
Hinge Lower and the Adjustable Screw Asm. Don't lay the refrigerator down in
working with it, it will cause to get out of order.
4. Be careful not to drop the door in disassembling or assembling the freezer or
the refrigerator door.
5. This refrigerator, according to the install position or user's liking, can be used
as the type of opening from the right or the left.

HOW TO REPLACE THE DOOR OPENING TYPE

1 Remove the hinge upper 2 Remove the Freezer Door

3 Remove the center hinge and the

Refrigerator Door 4 Remove the lower hinge

- 8-
 5 Reverse the position of the
adjustable screw assembly 6 Assemble the lower hinge

7 Move the cap and bracket to the

opposite side of the refrigerator door 8 Move the cap to the opposite side and
assemble the center hinge perpendicularly.

9 Assemble the door stopper for the

correct side of the freezer door 10 Move the Cap Cover to the opposite side
of the freezer door

11 Reverse the pin position of the upper

hinge
12 Assemble the screw to the top table until
it is strong enough to support the freezer
door. ( Torque value is 5 ~ 7 kgf )

-9-
4. ADJUSTMENT
4-1 COMPRESSOR 4-2-3 PTC-Applied Circuit Diagram
4-1-1 Role 펰 According to Starting Method of Motor
The compressor inhales low temperature and low pressure
gas evaporated from Evaporator of the Refrigerator, and
condenses this gas to high temperature and high pressure OVERLOAD PROTECTOR
gas, and then plays delivering role to Condenser.
C
4-1-2 Composition
The Compressor is Composed of Compressor Apparatus PTC COMPRESSOR
5 MOTOR
compressing gas, Compressor Motor moving Compressor
Apparatus and Case protecting Compressor Apparatus S M
S M
and Motor. There are PTC-Starter, and Over Load 3 6
Protector (OLP) in the Compressor outside. On the other
hand, because the Compressor consists of 1/1000mm processing PTC STARTER HERMETIC
precision components and is sealed after producing without dust TERMINAL
or humidity, deal and repair with care. RSIR

4-1-3 Note to Use

(1) Be careful not to allow over-voltage and over-current.
(2) No Strike 4-2-4 Motor Restarting and PTC Cooling
If applying forcible power or strike (dropping or careless (1) For restarting after power off during normal
dealing), poor operation and noise may occur. Compressor Motor operation, plug the power cord after
(3) Use proper electric components appropriate to the 5 min. for pressure balance of Refrigerating Cycle and
Compressor. PTC cooling.
(4) Note to Keep Compressor. (2) During normal operation of Compressor Motor, PTC
If Compressor gets wet in the rain and rust in the pin of elements generate heat continuously. Therefore,
Hermetic Terminal, poor operation and poor contact if PTC isn't cooled for a while after power off, Motor
may cause. can't operate again.
(5) Be careful that dust, humidity, and flux due to welding 4-2-5 Relation of PTC-Starter and OLP
don't inflow in Compressor inside in replacing (1) If power off during operation of Compressor and power
Compressor. Dust, humidity, and flux due to welding on before PTC is cooled, (instant shut-off within 2 min.
which inflows to Cylinder may cause lock and noise. or reconnect a power plug due to misconnecting),
PTC isn't cooled and a resistance value grows. As a
result, current can't flow to the sub-coil and Motor can't
4-2 PTC-STARTER operate and OLP operates by flowing over current in
only main-coil.
4-2-1 Composition of PTC-Starter (2) While the OLP repeats on and off operation about 3-5
(1) PTC (Positive Temperature Coefficient) is no-contact times, PTC is cooled and Compressor Motor performs
semiconductor starting device which uses ceramic normal operation.
material and the material consists of BaTiO3. If OLP doesn't operate when PTC is not cooled,
(2) The higher the temperature is, the higher resistance Compressor Motor is worn away and causes circuit-
value becomes . These features are used as starting short and fire. Therefore, use a proper fixed OLP
device of Motor. without fail.
4-2-2 Role of PTC-Starter 4-2-6 Note to Use PTC-Starter
(1) PTC is attached to Hermetic Compressor used for (1) Be careful not to allow over-voltage and over-current.
Refrigerator, Show Case and starts Motor. (2) No Strike
(2) Compressor for household refrigerator applies single- Don't apply a forcible power or strike.
phase induction Motor. (3) Keep apart from any liquid.
For normal operation of single-phase induction motor, in If liquid such as oil or water inflows into PTC,
the starting operation flows in both main coil and sub- PTC materials it may break due to insulation breakdown
coil. After the starting is over, the current is cut off in of material itself.
subcoil. The proper features of PTC play the above all (4) Don't change PTC at your convenience.
roles. So, PTC is used as a starting device of motor.
Don't disassemble PTC and mold. If damaging to
outside of PTC-starter, resistance value alters and poor
starting of compressor motor may cause.
(5) Use a properly fixed PTC.

- 10 -
4-3 OLP (OVER LOAD PROTECTOR) CONTACTING
4-3-1 Definition of OLP POINT
COVER
(1) OLP (OVER LOAD PROTECTOR) is attached to
Hermetic Compressor and protects Motor by cutting off BIMETAL
current in Compressor Motor by Bimetal in the OLP in
case of over-rising temperature.
(2) When over-voltage flows to Compressor motor, Bimetal CONTACTING
works by heating the heater inside OLP, POINT
and OLP protects Motor by cutting off current which HEATER
flows to Compressor Motor.
TERMINALS
4-3-2 Role of OLP
(1) OLP is attached to Hermetic Compressor used to
Refrigerator and Show Case and prevents Motor Coil BIMETAL
from being started in the Compressor.
ADJUST
(2) Do not turn the Adjust Screw of OLP in any way for SCREW
normal operation of OLP.
(Composition and connection Diagram of OLP

Figure 21
HEATER

5. CIRCUIT DIAGRAM

3854JN3003A

NOTE : 1. This is a basic diagram and specifications vary in different localities.

- 11 -
6. TROUBLESHOOTING
6-1 COMPRESSOR AND ELECTRIC COMPONENTS

Power Remove the PTC- (Rating Voltage YES

1 Source. Starter from the ±10%)? 2
Compressor and
measure the voltage
between Terminal C of
Compressor and
Terminals 5 or 6 of PTC.

YES
No Voltage. OLP disconnected? Replace OLP. 5

Check connection
condition.

Applied voltage isn't Advise the customer Reconnect.

in the range of Rating to use a regular
Voltage ±10%. Trans.
5

Check the Check the resistance YES

2 3
resistance of among M-C, S-C and
Motor M-S in Motor NO Replace Compressor.
Compressor. Compressor. 3 4 5

YES
Check the Check the resistance of 4
3 resistance of two terminals in PTC-
NO Replace
PTC-Starter. Starter. PTC-Starter. 5

YES
OLP works within YES
Check if applying 5
4 Check OLP.
a regular OLP. 30 sec. in forcible
OLP operation by NO
Replace OLP.
turning instant power
on and off.

Check Measure minimum Components start in YES

5 starting state. starting voltage after 5 the voltage of Rating O.K.
min. for balancing cycle Voltage ±10% below.
pressure and cooling the
PTC. NO
1

- 12 -
6-2 PTC AND OLP

Normal operation of Separate the PTC-Starter Observation value is Check another

Compressor is ʃ
from Compressor and 220V/50Hz : 22 ±30% electric
impossible or poor. ʃ
measure the resistance 115V/60Hz : 6.8 ±30% components.
ʃ 240V/50Hz : 33 ±30%
between No. 5 and 6 (only
ʃ 127, 220V/60Hz : 22
RSIR type) or No. 4 and 5 of
±30%
PTC-Starter with a Tester or
Whistone Bridge.
(Figure 37)
Replace
The resistance value is 0
PTC-Starter.
ʃor serveral hundreds .

ˆThe value is .

Separate the OLP from the YES Check another

Compressor and check the electric components.
resistance value between
two terminals of OLP with
a Tester. (Figure 38) NO
Replace OLP.

4
6 5
3

Figure 37 Figure 38

- 13 -
6-3 ANOTHER ELECTRIC COMPONENTS
Cooling is impossible

Compressor Check if current flows to

doesn't run. the following Cause.
components.

a. Thermistor Poor contacting.

b. Starting devices Shorted or broken.

c. OLP Poor contacting
or shorted.
d. Compressor coil Coil shorted.
Poor contacting Replace
e. Circuit Parts
or shorted. each component.

Running state of Check a starting

Low voltage. Raise the voltage.
Compressor is poor. voltage.

Check if current flows Poor contacting Replace

to starting devices. and broken. each component.

Check current flowing

Shorted.
in sub-coil of
Compressor.

Check capacity of OLP. Lack of capacity.

The items described Coil of motor Replace

above are normal. Compressor. the compressor.

Cooling ability is poor

Fan motor Check current flowing

Poor contacting.
doesn't run. in door S/W.
Replace
each component.
Check current flowing
Coil is shorted.
in the Fan Motor.

Much frost are sticked Check current flowing Shorted. Replace

to the EVAPORATOR. of the following each component.
components.
¥ Def. Sensor
¥ FUSE-M

Check current flowing

Replace
of the following
each component.
components.
¥ L-Cord
¥ Plate Heater

- 14 -
6-4 SERVICE DIAGNOSIS CHART

COMPLAINT POINTS TO BE CHECKED REMEDY

Cooling is ¥ Is the power cord unplugged from the outlet? ¥ Plug to the outlet.
impossible. ¥ Check if the power S/W is set to OFF. ¥ Set the switch to ON.
¥ Check if the fuse of power S/W 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 putting in hot foods. ¥ Put in foods after they get cold.
¥ 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 Control is set to "Min". ¥ Set the control to mid-position.

Foods in the ¥ Are foods placed in cooling air outlet? ¥ Place foods in high temperature section.
Refrigerator ¥ (Front Part)
are frozen. ¥ Check if the Display LED is set to "Max". ¥ Set the Display LED to "Mid".
¥ Is the ambient temperature below 5¡C? ¥ Set the Display LED to "Min".

Dew or ice ¥ Is watery foods kept? ¥ Seal up watery foods with wrap.
forms in the ¥ Check if putting in hot foods. ¥ Put in foods after they get cold.
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 up. ¥ it firmly.

Dew forms ¥ Check if ambient temperature and humidity ¥ Wipe dew with a dry cloth. This happening
in the Out Case. of surroumcling air are high. ¥ is solved in low temperature and humidity
¥ naturally.
¥ Is the gap in the door packed? ¥ Fill up the gap.

Abnormal ¥ Is the set positioned in a firm and even place? ¥ Adjust the Adjust Screw, and position
noise generates. ¥ in the firm place.
¥ Does any unnecessary objects exist ¥ Remove the objects.
¥ in the back side of the set?
¥ Check if the Drip Tray is not firmly fixed. ¥ Fix it firmly on an original position.
¥ Check if the cover of mechanical room ¥ Place the cover at an original position.
¥ in below and front side is taken out.

To close the door ¥ Check if the door packing becomes dirty ¥ Clean the door packing.
is not handy. ¥ by filth such as juice.
¥ Is the set positioned in a firm and even place? ¥ Position in the firm place and adjust the
¥ Adjust Screw.
¥ Is too much food putted in the set? ¥ Keep foods not to reach the door.

Ice and foods ¥ Check if the inside of the set becomes dirty. ¥ Clean the inside of the set.
smell unpleasant. ¥ Did you keep smelly foods without wraping? ¥ Wrap smelly foods.
¥ It smells plastic. ¥ The new products smell plastic, but it is
¥ removed after 1-2 weeks.

 In addition to the items described left, refer to the followings to solve the complaint.

Replace the
Check if dew forms in Defrosting
Components of
the Freezer. is poor.
defrosting circuit.

Check Refrigerating The cycle

Repair the cycle.
Cycle. is faulty.

The operation of
Check the Replace the
the Thermistor is
Thermistor Thermistor.
poor.

- 15 -
 6-5 REFRIGERATING CYCLE
Troubleshooting Chart

TEMPERATURE
STATE OF STATE OF THE
CAUSE OF THE REMARKS
THE SET EVAPORATOR
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 get cold frost forms in inlet only ambient ¥ Normal cooling is possible
LEAKAGE

normally. temperature. ¥ when injecting Refrigerant

¥ of regular amount.

WHOLE Freezer room 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 get cold formed. ¥ when injecting Refrigerant
normally. ¥ of regular amount.

PARTIAL Freeze room and Flowing sound of Refrigerant A little high ¥ Normal discharging of
CLOGGED BY DUST

CLOG Refrigerator is heard and frost forms more than ¥ refrigerant.

don't get cold in inlet only. ambient ¥ The capillary tube is faulty.
normally. temperature.

WHOLE Freezer room and Flowing sound of Refrigerant Equal to ambient ¥ Normal discharging of
CLOG Refrigerator is not heard and frost isn't temperature. ¥ Refrigerant.
don't get cold. formed.

MOISTURE Cooling operation Flowing sound of Refrigerant Low than ¥ Cooling operation restarts
CLOG stops periodically. is not heard and frost melts. ambient ¥ when heating the inlet of
temperature ¥ capillary tube.
COMPRESSION

COMP- Freezer and Low flowing sound of A little high ¥ The pressure of high
DEFECTIVE

RESSION Refrigerator Refrigerant is heard and than ambient ¥ pressure part in

don't get cold. 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 compressor.

Leakage Detection
콀 Observe discharging point of refrigerant which may be in oil discharging part in compressor and hole of evaporator.

Whether frost
Whether Compressor YES forms or not in Whether oil
runs or not. Evaporator. No frost leaks or not.
or forms
in inlet only
Frost formed normally
Observe the discharging
Normal amount amount of Refrigerant.

No or much amount YES

Faulty Inject Refrigerant to Compressor

Moisture Clog. and check cooling operation.
Compressor.

Check Compressor Clogged by dust. Gas leakage.

Normal frost formed in
Evaporator (Check the leakage point)

- 16 -
General Control of Refrigerating Cycle

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
(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 a day. (1)
(1) ¥¥Borax 30% ¥ Holding period: 1 day
(1) ¥¥Borax 35% ¥ Close the cover of container to prevent dust
2 (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 in a outdoor because
ASM (1) after unpacking. ¥ humidity damages to it.
3 (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 of 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
4 (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.

DRY AND (1) The pressure of dry air must be more

AIR than 12~16Kg/cm2
NITROGEN (2) Temperature must be more than
5
GAS -20_ 70¡C.
(3) Keep the pressure to 12~6Kg/cm2 also
(3) when substituting dry air for Nitrogen Gas.

NIPPLE (1) Check if gas leaks with soapy water. ¥ Check if gas leaks from connecting part of
6 AND (2) Replace Quick Coupler in case of leakage. ¥ Coupler.
COUPLER

PIPE (1)¥ Put all Joint Pipe in a clean box and

7 (1)¥ cover tightly with the lid so that dust or
(1)¥ humidity is not inserted.

- 17 -
7. DESCRIPTION OF FUNCTION & CIRCUIT OF MICOM
The following description is basically for GR-262/GR-292. For the other models, refer to the diagram of the entire PCB
Circuit.

7-1 FUNCTION
7-1-1 FUNCTION
1. When the appliance is plugged in, it is set to ‘Medium’. Each time the button is pushed, it is set to
‘Medium’Õ‘Medium/High’Õ‘High’Õ‘Low’Õ‘Medium/Low’Õ‘Medium’in order.
2. When the power is initially applied or restored after a power failure, it is automatically set to ‘Medium’.

Medium\ Medium\
Low Medium High High
Low
Temp
Control

TEMP(ºC) 6 4.5 3 1 -1
ROOM REFRIGERATOR

Ref
. Temp Control

- 18 -
7-1-2 DEFROSTING
1. The defrosting is performed each time when the total running time of the compressor reaches 7 hours.
2. After the power is turned on (or restored after a power failure), the defrosting starts when the total running time of the
compressor reaches 4 hours.
3. When the temperature of the defrosting sensor reaches 13 °C or above, the defrosting stops. If the temperature does not
reach 13 °C in 2 hours after the defrosting starts, the defrosting error code is displayed.
(Refer to 7-1-4 Error Diagnostic Mode.)
4. With the defective defrosting sensor (cut or short-circuited wire), the defrosting will not be performed.

7-1-3 SEQUENTIAL OPERATION OF ELECTRIC COMPONENTS

The electric components, such as the comp, defrosting heater, and cooling fan, start sequentially to avoid the noise and
damage to the part, which may result from the simultaneous start of various components on turning the power on or after
the completion of a test.

Condition of Operation Operating Sequence

If the temp of the defrosting

When the power is turned on

sensor is 25 °C or above POWER in 0.5 sec COMP & COOLING FAN

(For the initial use after the ON ON
purchase or grounding)

POWER in 0.5 sec DEFROSTING in 10 sec DEFROSTING

If the temp of the defrosting ON HEATER ON HEATER OFF
sensor is below 25 °C
(After a power failure or SVC)
in 0.5 sec COMP & COOLING FAN
ON

- 19 -
7-1-4 ERROR DIAGNOSTIC MODE
1. The error diagnostic mode allows the SVC when a fault that may affect the performance of the product occurs while
operating the product.
2. Even if the function control button is pushed when an error occurs, the function will not be performed.
3. When the error is cleared while the error code is displayed due to a fault, the appliance returns to the normal condition
(Reset).
4. The error code is displayed by the refrigerator temp indication LED on the display of the refrigerator while the remaining
LEDs are off.

R1 R2 R3

Ref
. Temp Control

: ON : OFF

Error Code Display State of Operation with Error

NO Error Cause
R1 R2 R3 Comp / Cooling fan Defrosting heater

Faulty refrigerator(R) Cut or short-circuited wire of 15 min ON/

1. sensor (on the control refrigerator sensor 15 min OFF
box of the refrigerator)

2. Faulty defrosting sensor Cut or short-circuited wire of No defrosting

defrosting sensor

Cut or disconnected wire of

3. Defrosting failure defrosting heater or temperature
fuse(indicated at least 2 hours
later after the error occurs)

- 20 -
7-2 PCB FUNCTION
7-2-1 POWER CIRCUIT

The secondary part of the TRANS is composed of the power supply for the display and relay drive (12Vdc) and that for the
MICOM and IC (5Vdc).
The voltage for each part is as follows.

PART VA 1 CE 2 CE3

VOLTAGE 220 Vac 12 Vdc 5 Vdc

VA1 is a part for preventing the over voltage and noise. When 385V or higher power is applied, the inside elements are
short-circuited and broken, resulting in the blowout of the fuse in order to protect the elements of the secondary part of the
TRANS.

- 21 -
7-2-2 OSCILLATION CIRCUIT

This circuit is to generate the base clock for calculating time and the synchro clock for transmitting data from and to the
inside logic elements of the IC1(MICOM). Be sure to use the authentic parts since the calculating time by the IC1 may be
changed or it will not work if the OSC1 SPEC is changed.

7-2-3 RESET CIRCUIT

The RESET circuit is for allowing all the functions to start at the initial conditions by initializing various parts including the
RAM inside the MICOM (IC1) when the power is initially supplied or the power supply to the MICOM is restored after a
momentary power failure. For the initial 10ms of power supply, ‘LOW’ voltage is applied to the MICOM RESET terminal.
During a normal operation, 5V is applied to the RESET terminal. (If a trouble occurs in the RESET IC, the MICOM will not
work.)

- 22 -
7-2-4 LOAD DRIVE CIRCUIT
1. Load Drive Condition Check

Comp,
Load Type Defrosting Heater
Freezer Fan Motor

Measurement Location A B
ON 1V or below
Condition
OFF 12V

- 23 -
7-2-5 TEMPERATURE SENSOR CIRCUIT

The upper CIRCUIT reads REFRIGERATOR temperature and DEF-SENSOR temperature for defrosting into MICOM.
OPENING or SHORT state of each TEMPERATURE SENSOR are as follows.

SENSOR CHECK POINT NORMAL(-30 °C ~ 50 °C) SHORT-CIRCUITED OPEN

Refrigerator Sensor POINT A Voltage

0.5 V ~ 4.5 V 0V 5V
Defrosting Sensor POINT B Voltage

- 24 -
7-2-6 TEMPERATURE COMPENSATION & OVERCOOLING/UNDERCOOLING COMPENSATION CIRCUIT
1. Refrigerator Temperature Compensation

Refrigerator
Resistance Temperature Remark
(RCR1) Compensation
180 KΩ +5.0 ¡C Compensation by
raising the
56 KΩ +4.0 ¡C
temperature
33 KΩ +3.0 ¡C
18 KΩ +2.0 ¡C
12 KΩ +1.0 ¡C
10 KΩ 0 ¡C Standard Temperature
8.2 KΩ -1.0 ¡C Compensation by
lowering the
5.6 KΩ -2.0 ¡C
temperature
3.3 KΩ -3.0 ¡C
2 KΩ -4.0 ¡C
470 Ω -5.0 ¡C

➧ Table of Temperature Compensation by adjusting the resistance (Difference with the current temperature)
E.g.) If the refrigerator compensation resistance (RCR1) is changed from 10K (the current resistance) to 18K
(the adjustment resistance), the temperature of the refrigerator rises +2 ¡C.

- 25 -
7-2-7 KEY BUTTON INPUT & DISPLAY LIGHT ON CIRCUIT

➧ The circuit shown above is to determine whether a function control key on the operation display is pushed and to turn on
the corresponding function indication LED. The drive type is the scan type.

- 26 -
7-3. RESISTANCE SPECIFICATION OF SENSOR

TEMPERATURE SENSOR RESISTANCE OF REFRIGERATOR

(DEFROST) SENSOR

- 20 ºC 77 KΩ

- 15 ûC 60 KΩ

- 10 ûC 47.3 KΩ

- 5 ûC 38.4 KΩ

0 ûC 30 KΩ

+ 5 ûC 24.1 KΩ

+ 10 ûC 19.5 KΩ

+ 15 ûC 15.9 KΩ

+ 20 ûC 13 KΩ

+ 25 ûC 11 KΩ

+ 30 ûC 8.9 KΩ

+ 40 ûC 6.2 KΩ

+ 50 ûC 4.3 KΩ

• The resistance of SENSOR has ±5% common difference.

• Measure the resistance of SENSOR after leaving it over 3 minutes in measuring temperature.
This postponing is necessary because of perceiving speed.
• Measure the F-SENSOR, SUPER FROST SENSOR, R1, R2-SENSOR after disconnect CON5 of PWB ASSY, MAIN.

- 27 -
7-4. TROUBLE SHOOTING
¥ Replace PCB when no trouble after checking the contents of trouble.
CLASSIFICATION STATE OF TROUBLE POINT BE CHECKED CHECKING METHOD CONTENT REMEDY
POWER SOURCE 1. All the DISPLAY 1. FREEZER/ FREEZER/REFRIGERATOR POWER SOURCE is poor Certify Fuse.
is poor LED OFF REFRIGERATOR DOOR OPEN Certify outlet Voltage.
2. DISPLAY LED 2. LAMP is dim. CHECK with the naked. Applied voltage mistake Use boosting TRANS.
represents abnormal 3. The connection of Certify connection of CONNECTOR connection Reconnect CONNECTOR.
operation. CONNECTOR of MAIN PWB. CONNECTOR. is poor.
TRANS FUSE open. Replace TRANS.
COOLING is poor NO COOLING 1. COMPRESSOR operates? Check the MAIN PCB. COMPRESSOR lock or Replace COMPRESSOR.
blocked.
OLP, PTC is poor. Replace OLP, PTC.
COMPRESSOR RELAY is Replace MAIN PWB RY1
poor
THE CONNECTING WIRE Certify the black wire of MAIN

- 28 -
is poor. PWB CONNECTOR (CON1)
2. Whether refrigerant leaks or Measure the amount of frost Refrigerant leakage. Remedy the leaking part
leaks or not. sticking on EVA and the and reaching Refrigerant.
surface temperature of
condenser pipe.
FREEZER 1. Whether FAN MOTOR Check the MAIN PCB. FAN MOTOR is poor Replace FAN MOTOR.
TEMPERATURE is poor operates or not. DOOR LINE contact. Replace DOOR LINER.
CONETTING WIRE is poor. Certify MOTOR and the
connection of the black wire
of MAIN PWB CONNECTOR.
(CON1)
2. DEFROSTING normal? Certify the amount of frost DEFROSTING is poor. See the DEFROSTING
sticking on EVA. trouble.
3. SENSOR normal? Check resistance the SENSOR RESISTANCE is Replace SENSOR
SENSOR in the poor.
Refrigerator
CLASSIFICATION STATE OF TROUBLE POINT BE CHECKED CHECKING METHOD CONTENT REMEDY
COOLING is poor. REFRIGERATOR 1. FREEZER TEMPERATURE See "FREEZER Certify the attaching state
TEMPERATURE is is normal? TEMPERATURE is poor". of DOOR.
poor. 2. Cool air of FAN MOTOR is Certify the amount of cool air FAN MOTOR is poor. Replace FAN MOTOR.
is sufficient? and its speed touching check Passage of cool air blocking. Remove impurities.
supplied into
REFRIGERATOR EVA frozen. See "DEFROSTING is poor".

- 29 -
DEFROSTING is NO DEFROSTING. 1. HEATER emit heat? Check the MAIN PCB. HEATER disconnection. Replace HEATER.
poor.
TEMPERATURE FUSE Replace TEMPERATURE
disconnection. FUSE.
Connection is poor. Certify EVA connection and
wire of MAIN PWB
CONNECTOR (CON1)
DEF-SENSOR is poor. Replace DEF-SENSOR.
HEATER RELAY is poor. Replace RY2 of MAIN PWB.
2. DRAIN PIPE blocking? Certify DRAIN PIPE. DRAIN PIPE blocking. Remove ice and impurities.
Certify HEATER PLATE
resistance.
3. Remain ice at Certify the attaching Attaching is poor. Reassemble DEF-SENSOR.
DEFROSTING? of DEF-SENSOR.
Certify the attaching DOOR sticking is poor. Reassemble DOOR.
state(gap) of FREEZER/ Replace GASKET.
REFRIGERATOR DOOR.
7-4 MAIN PWB ASS'Y AND PARTS LIST
7-4-1 MAIN PWB ASS'Y
1. R-B52DZ/R-B55DZ

- 30 -
7-4-2 REPLACEMENT PARTS LIST

- 31 -
7-4-3 PWB ASS'Y, DISPLAY AND PARTS LIST

No P/No Description Spec Maker Bigo

1 6870JB2061A PWB(PCB),DISPLAY R-B29 (HM-PJT) DOO SAN -
2 6600JB8005A SWITCH KPT-1105A KYUNG IN SW101
3 0DL500329AA LED SV50-R032BF569GG SEOUL SEMI. L101~L103
4 0DD414809AA DIODE, SWITCHING 1N4148 26MM - -
5 - LEAD WIRE UL1007 AWG24 (VSF 0.18/12/0.3MM2) -
6 - LEAD WIRE UL1007 AWG24 (VSF 0.18/12/0.3MM )
2
-
7 - LEAD WIRE UL1007 AWG24 (VSF 0.18/12/0.3MM2) -
8 - LEAD WIRE UL1007 AWG24 (VSF 0.18/12/0.3MM )
2
-
9 - LEAD WIRE UL1007 AWG24 (VSF 0.18/12/0.3MM2) -
14 - HOUSING #316092-1 AMP 8P
15 - TAP. #917764-1 AMP -
16 - DOUBLE LOCK PLATE #917704-1 AMP 8P
17 - HOUSING #35022-0006 MOLEX (WHITE)
18 - CONTACT #35021-1101(PBT) MOLEX -
19 - TAPE, VINYL (W19xL60MM=1) -
22 6500JB1001S SENSOR, TEMPERATURE K43 PVC R-SENSOR - (200MM)
26 49111001 SOLDER, SOLDERING ALMIT KR-19RMA )&&46/( -
27 49111004 SOLDER, LEAD BAR S63S-B20 %"&+*/ SOLD’
28 59333105 FLUX JS71 KOKI -

- 32 -
7-5 PWB DIAGRAM

- 33 -
- 34 -
7. EXPLODED VIEW
The parts of refrigerator and the shape of each part are subject to change in different localities.

*: optional parts
301A
103A

281A

281B
103B

281E * 401A
303A

418A
303A
501F
411A
501A
125L * 282B
*
410G
410H *

406B
120A
109A *
501K
105A
318A
317A 158C
314A

310A
327A

409B
283B
308A 309A
106A
307A 604E*
312A
125L 103C * 604F*
106B
319A
109B

407A

315A

- 35 -
*: optional parts
405C
405A
330B 332A

404A

329A

110B *
125A * 131A *
125H *
149A

125A *
131A *

149B

140A

149C

* 605A 149C

154A

* 6 05 B

151A

- 36 -
 200A

203A 201A

212G *

109B *

212A

212C
212C

212G
205A

212A 212C

235A
230A
233A

210A
210A
231A

241B

* 231A

241D
212A

212C

212A
212C

243A

- 37 -
P/No. 3828JP8010B