LG GR-359, GR-399 Service Manual

CAUTION

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

MODEL: GR-359/399

REFRIGERATOR

SERVICE MANUAL

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

DEF' CONTROL ASM .......................................................................................................................................................... 8

LAMP.................................................................................................................................................................................... 8

ADJUSTMENT................................................................................................................................................................... 9-10

COMPRESSOR.................................................................................................................................................................... 9

PTC-STARTER..................................................................................................................................................................... 9

OLP (OVER LOAD PROTECTOR)..................................................................................................................................... 10

CIRCUIT DIAGRAM.............................................................................................................................................................. 10

TROUBLESHOOTING..................................................................................................................................................... 11-16

COMPRESSOR AND ELECTRIC COMPONENTS ........................................................................................................... 11

PTC AND OLP.................................................................................................................................................................... 12

ANOTHER ELECTRIC COMPONENT............................................................................................................................... 13

SERVICE DIAGNOSIS CHART.......................................................................................................................................... 14

REFRIGERATING CYCLE............................................................................................................................................ 15-16

MICOM FUNCTION & PCB CIRCUIT EXPLANATION................................................................................................... 17-34

EXPLODED VIEW .......................................................................................................................................................... 35-38

REPLACEMENT PARTS LIST............................................................................................................................................ 39-

Please read the following instructions before servicing your
refrigerator.

1. Check the set for electric losses.

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 following 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.

11. When you discharge the refrigerant, wear the
protective safety glasses or goggle for eye safety.

12. When you repair the cycle system in refrigerator, the
work area is well ventilated.
Especially if the refrigerant is R600a, there are no fire
or heat sources. (No smoking)

SAFETY PRECAUTIONS

CONTENTS

- 2 -

- 17 -

ASSEMBLY JAWS

BOLT

TOOL

TUBE

LOKRING

LOKRING

JOINT

Figure 23. LOKRING

Figure 24. LOKRING TOOL

Features of refrigerant (R600a)

• Achromatic and odor less gas.

• Flammable gas and the ignition (explosion) at 494°C.

• Upper/lower explosion limit: 1.8%~8.4%/Vol.

Features of the R600a refrigerator

•

Charging of 60% refrigerant compared with a R134a model

•

The suction pressure is below 1bar (abs) during the operation.

• Because of its low suction pressure, the external air may
flow in the cycle system when the refrigerant leak, and it
causes malfunction in the compressor.

• The displacement of compressor using R600a must be at
least 1.7 times larger than that of R134a.

• Any type of dryer is applicable (XH-5, 7, 9).

• The EVAPORATOR or any other cycle part that has
welding joint is hidden in the foam. (If not hidden inside,
the whole electric parts must be tested with the
LEAKAGE TEST according to the IEC Standard.)

• The compressor has label of the refrigerant R600a.

• Only the SVC man must have an access to the system.

Installation place

• Must be well ventilated.

• Must be 20 m

3

or larger.

• Must be no-smoking area.

• No ignitable factors must be present.

Utilities

• Refrigerant cylinder (MAX NET 300g)

• Manometer

• Vacuum pump (600L/min)

• Piercing Clamp

• Quick coupler

• Hoses (5m-1EA, 1m-3EA)

• LOKRING

• Portable Leakage detector (3g/year

↓)

• Nitrogen cylinder (for leakage test)

• Concentration gauge

Make sure before Servicing

• Refrigerant
Confirm the refrigerant by checking Name Plate and the label
on the compressor, after opening the COVER ASSY,
BACK-M/C.

• If the refrigerant is R600a, you must not weld or apply a
heat source.

Air Recharging in Compressor

Before refilling the refrigerant, you must perform the test according
to Chapter 5 (TROUBLESHOOTING CHAR T). When the defects
are found, you must discharge the residual refrigerant (R600a) in
the outdoor. For discharging the refrigerant R600a, break the
narrow portion of tube extension by hand or with a pipe cutter as
shown in Figure 1. Leave it f or 30min in outside to stabilize the
pressure with ambient. Then, check the pressure by piercing the
dryer part with piercing pliers. If the refrigerant is not completely
discharged, let the refrigerator alone for more 30min in outside.

Attach the service tube installed with a Schrader valve (one-way
valve) by using the LOKRING (Figure 2). Then, connect the
Schrader valve (one-wa y v alv e) to the pump that is connected to
the discharging hose leading to the outside. When discharging the
residual refrigerant, repeat 3 cycle that includes 3min of the pump
running->pump off->30sec of the compressor running.

After the refrigerant (R600a) is completely discharged, repair any
defective parts and replace the dryer. At any case y ou must use the
LOKRING for connecting or replacing any part in the cycle (No Fire,
No Welding). Connect the Schrader valv e to pump with the coupler .
And then turn the pump on for vacuum state (Figure 3). Let the
pump run until the low-pressure gauge indicates the vacuum (gauge
pressure 0, absolute pressure -1atm or -760mmHg). Recommended
vacuum time is 30 min. Charge the N

2 gas in order to check for

leakage from welding points and the LOKRING. If leakages are
found, repair the defects and repeat the v acuum process.

After the system is completely vacuumed, fill it with the refrigerant
R600a up to what has been specified at your refrigerator Name
Plate. The amount of refrigerant (R600a) must be precisely
measured within the error of ±2g by an electron scale (Figure 4).

If you use the manifold connected with both the refrigerant
(R600a) cylinder and the vacuum pump simultaneously,
make sure the pump valve is closed (Figure 5).

Connect the charging hose (that is connected to the refrigerant
(R600a) cylinder) to the Schrader valve installed on the service
tube. Then, charge the refrigerant (R600a) by controlling the
Throttle valve. When y ou do so , do not fully open the Throttle valve
because it may make damage to the compressor. Gradually charge
the refrigerant (R600a) by changing open and close the Throttle
Valv e (5g at each time). The charging hose m ust use a one-w a y
valve to pre v ent the refrigerant refluence. Close the Schr ader v alv e
cap after the refrigerant (R600a) is completely recharged.

After you completely recharge the refrigerant (R600a), perform the
leakage test by using a portable leakage detector or soapy water.
Test the low pressure (suction) parts in compressor off time and
high pressure parts in compressor on time. If the leakages are
found, restart from the refrigerant (R600a) discharging process and
repairs defects of leaks.

After the leakage test, check the temperature of each parts of the
cycle. Check with hands if the CONDENSER and the case (HO T­LINE pipe) that is contacted to the door gasket are warm. Confirm
that frost is uniform distributed on the surface of the EVAPORAT OR.

TO THE
VACUUM
PUMP

PRESSURE
GAUGE

Figure 3

WEIGH SCALE

THROTTLE
VALVE

COUPLE

REFRIGERANT
(R600a)

CHARGING HOSE

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 -

POINT TO BE
BROKEN

CHARGE TUBE
EXTENSION

SCHRADER VALVE
(ONE-WAY VALVE)

LOKRING

SERVICE TUBE
EXTENSION

Figure 1 Figure 2

1.Ref. No: GR-399

2.Ref. No: GR-359

ITEMS SPECIFICATIONS

DIMENSIONS (mm) 595(W)X626(D)X1880(H)
NET WEIGHT (kg) 74
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 & Heater, Cord-L
REFRIGERANT R600a(54g)
LUBRICATION OIL FREOL S10(280 cc)

TEMPERATURE

CONTROL

ITEMS SPECIFICATIONS

Transparent Shelf(3 EA)
REFRIGERATOR Vegetable Container(2 EA)
COMPARTMENT

Vegetable Container Cover(1 EA)

Chilled Container(1 EA)*

Dairy Pocket Cover(1 EA)

Egg Tray(2 EA)
DOOR POCKET

Little Pocket(5 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

SPECIFICATIONS

- 4 -

* Optional Parts

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 & Heater, Cord-L
REFRIGERANT R600a(54g)
LUBRICATION OIL FREOL S10(280 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

* Optional Parts

or Vinyl Coated Metal

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 or 5)

Utility Corner
(movable)

Bottle Holder

2L Bottle
Door Basket

Leveling Screw

Egg Tray(1 or 2)

Freezer Temperature

Control

Removable

Glass Shelf(2 or 3)

Lamp

Multi-air Flow Duct

Fresh Meat Keeper

(Optional)

Refrigerator

Temperature Control

Vegetable Drawer

Used to keep fruits

and vegetables, etc.

fresh and crisp.

Ice Cube Tray

Freezer

Compartment

Removable

Plinth

1. PRECAUTION

1) Before reversing the door, first of all, you should take
out 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 to get out of order.

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) Seperate screw ➋ and remove lower cover ➊ and move

cap lower cover

➌. And, seperate screw ➍, lower hinge

➎, and remove pin ➏. Separating the freezer door in

opening, and more the position the cap

➐.

Move the position of bracket door

➑ and screw ➒.

2) Separating screw and remove the center hinge
and the refrigerator door . Move the position of cap .
Move the position of bracket door and screw .

3) Move the position of upper hinge pin , and cap .
Assemble the refrigerator door . Assemble center
hinge and bolt . Assemble freezer door .
Assemble the lower hinge

➎, bolt ➍ and lower cover ➊.

REPLACEMENT OF DOOR OPENING TYPE

- 6 -

21

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

1110

12

16 17

13

15

12

11 10

21

14

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 Assy, 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 Assy, 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 ROOM LAMP

1) Remove the Cover Lamp, R by pulling with a '–' type
driver.

2) Remove the Lamp by turning.

3) After removing the lamp, you must check
the O-RING, which is made by rubber and prevent
electric spark, in the socket.

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, F.

4) Disconnect the housing of lead wire.

5) Separate the Fan Assy.

6) Losse 2 screw fixed to the Bracket.

7) Pull out Shroud, F remove the Fan Motor Assy.

8) Separate the Motor Bracket and Rubber.

5 DEFROST CONTROL ASSY

Defrost Control Assy consists of Thermistor and Fuse, Melting.
Thermistor functions to defrost automatically and it is attached to
metal side of the Evaporator and senses temperature.

Fuse, Melting 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, F after removing the Grille.

2) Separate the connector connected with the Defrost Control
Assy and replace new one.

6 DAMPER CONTROL

1) Remove the Cover Lamp, R and loosen 2 screw.

2) Pull the Control Box, R and separate the lead wire
housing.

3) Remove the Cover Lamp, R.

4) Separate the Insulation Multi Duct and Control Box, R.

5) Disassemble the Knob.

6) Separate the Damper Control and Control Box, R.

7) Separate the Damper Control and Resistor.

8) Disconnect the lead wire.

7 HEATER, SHEATH & HEATER, CORD-L

In this refrigerator, Heater, Sheath & Heater, Cord-L are
used for defrosting heater. During heating, the temperature
of heater rises about 300~350°C. Therefore, be careful not
to burn while servicing.

1) After removing the Grille and Shroud, separate the
Heater, Sheath by disconnecting the connectors.

2) Exchanged Heater, Sheath and connected the housing.

3) If the Heater, Cord-L is defected, disconnect the
connectors, and separate the Heater, Cord-L with
Long Nose.

4) Replace and assembly the Heater, Cord-L and connect
the connectors.

REFRIGERATOR ROOM LAMP

Heater, Sheath

Heater, Cord-L

GUIDE FAN

FAN

SHROUD

FAN MOTOR

GRILLE

Thermister

Fuse, Melting

Figure 13

Figure 14

Figure 11

Figure 12

- 8 -

ADJUSTMENT

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 is Relay Assy (one set of PTC-Starter
and Over Load Protector (OLP)) in Compressor. 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) 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.

If Compressor gets wet in the rain and rust in the pin of
Hermetic Terminal, the result may be poor operation
and poor contact may cause.

(5) Be careful that dust, humidity, and flux welding don't

inflow 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 and this material consists of BaTiO

3.

(2) The higher the temperature is, the higher becomes the

resistance value. These features are used as 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 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, 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 circuit­short 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) No Strike

Don't apply a forcible power or strike.

(3) Keep apart from any liquid.

If liquid such as oil or water away enter the PTC,
PTC materials it 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 to the
PTC-starter is damaged, resistance value is altered and
it may cause poor starting of the compressor motor may
cause.

(5) Use a properly fixed PTC.

PTC STARTER

HERMETIC

TERMINAL

COMPRESSOR
MOTOR

C

M

S

M

3

M

S

S

PTC

OVERLOAD

PROTECTOR(O.L.P)

RSIR

RELAY ASSY

Figure 19

- 9 -

CIRCUIT DIAGRAM

- 10 -

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

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

NO

YES

YES

NO

NO

5

YES

NO

YES

Power
Source.

Remove the Relay Assy
from the Compressor
and measure the voltage
between Terminal C of
Compressor and
Terminals M or S of
Relay Assy

No Voltage.

(Rating Voltage
±10%)?

Replace
Relay Assy

Replace
Relay Assy

O.K.

Advise the customer
to use a regular
Trans.

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.

2 RELAY ASSY (PTC AND OLP)

- 12 -

LN

T

32

2

MCSMCS

YES

NO

Normal operation of
Compressor is
impossible or poor.

Separate the Relay Assy
from Compressor and
measure the resistance
between M and S with a
Tester or Whistone Bridge.
(Figure 21)

Separate the Relay Assy
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 Relay Assy.

Check another
electric
components.

Replace
Relay Assy.

Figure 21 Figure 22