LG LMX28994 Series User manual

CAUTION
BEFORE SERVICING THE UNIT,
READ THE SAFETY PRECAUTIONS IN THIS MANUAL.
MODEL : LMX28994** COLOR : STAINLESS(ST)
REFRIGERATOR
SERVICE MANUAL

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CONTENTS
SAFETY PRECAUTIONS ....................................................................................................................................................... 2
1. SPECIFICATIONS ............................................................................................................................................................. 3
2. PARTS IDENTIFICATION ................................................................................................................................................. 4
3. DISASSEMBLY ............................................................................................................................................................ 5-21
REMOVING AND REPLACING REFRIGERATOR DOORS ............................................................................................. 5
DOOR ................................................................................................................................................................................ 6
DOOR ALIGNMENT .......................................................................................................................................................... 7
GRILLE ASSEMBLY .......................................................................................................................................................... 7
FAN AND FAN MOTOR ..................................................................................................................................................... 7
DEFROST CONTROL ASSEMBLY ................................................................................................................................... 8
LAMP ................................................................................................................................................................................. 8
MULTI DUCT ..................................................................................................................................................................... 8
MAIN PWB ......................................................................................................................................................................... 9
DISPENSER ...................................................................................................................................................................... 9
ICE BUTTON ASSEMBLY ................................................................................................................................................. 9
WATER BUTTON ASSMEBLY ........................................................................................................................................ 10
ICE CORNER DOOR REPLACEMENT ........................................................................................................................... 10
ICEMAKER REPLACEMENT .......................................................................................................................................... 10
SUB PWB FOR WORKING DISPENSER ....................................................................................................................... 11
CAP DUCT MOTOR REPLACEMENT ............................................................................................................................ 11
HOW TO REMOVE A ICE BIN ........................................................................................................................................ 12
HOW TO INSERT A ICE BIN ........................................................................................................................................... 12
HOW TO REPLACE THE CONVERTA DISPLAY ........................................................................................................... 13
HOW TO REPLACE THE CONVERTA JOINT ........................................................................................................... 14-15
HOW TO REPLACE THE AUTO DRAWER MOTOR ................................................................................................. 16-17
HOW TO REPLACE THE AUTO DRAWER JOINT..................................................................................................... 17-19
WATER VALVE DISASSEMBLY METHOD .................................................................................................................... 20
FAN AND FAN MOTOR DISASSEMBLY METHOD ........................................................................................................ 20
TOP DRAWER ................................................................................................................................................................. 21
BOTTOM DRAWER ......................................................................................................................................................... 21
4. ADJUSTMENT ........................................................................................................................................................... 22-24
COMPRESSOR ................................................................................................................................................................ 22
INTRODUCTION OF E-LINEAR COMPRESSOR ...................................................................................................... 22-24
5. CIRCUIT DIAGRAM ........................................................................................................................................................ 25
6. TROUBLESHOOTING ............................................................................................................................................... 26-50
7. REFERENCE .............................................................................................................................................................. 51-56
8. COMPONENT TESTING INFORMATION .................................................................................................................. 57-64
9. TROUBLESHOOTING ............................................................................................................................................. 65- 71
10. ICEMAKER OPEARTING AND TROUBLE SHOOTING METHOD ......................................................................... 72-75
11. DESCRIPTION OF FUNCTION & CIRCUIT OF MICOM ........................................................................................... 76-79
12. EXPLODED VIEW & REPLACEMENT PARTS LIST ................................................................................................ 80-86
SAFETY PRECAUTIONS
Please read the following instructions before servicing your refrigerator.
1. Unplug the power before handling any elctrical componets.
2. Check the rated current, voltage, and capacity.
3. Take caution not to get water near any electrical components.
4. Use exact replacement parts.
5. Remove any objects from the top prior to tilting the product.

1-1 LMX28994**
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1. SPECIFICATIONS
DOOR DESIGN
DIMENSIONS (inches)
NET WEIGHT (pounds)
COOLING SYSTEM
TEMPERATURE CONTROL
DEFROSTING SYSTEM
DOOR FINISH
HANDLE TYPE
INNER CASE
INSULATION
ITEMS
Side Rounded
35 3/4 X 35 3/8 X 69 3/4 (WXDXH) 27cu.ft.
175 kg. (386 lb)
Fan Cooling
Micom Control
Full Automatic
Heater Defrost
PCM, VCM, Stainless
Bar
ABS Resin
Polyurethane Foam
SPECIFICATIONS
VEGETABLE TRAY
COMPRESSOR
EVAPORATOR
CONDENSER
REFRIGERANT
LUBRICATING OIL
DEFROSTING DEVICE
ITEMS
Clear Drawer Type
Linear
Fin Tube Type
Spiral Condenser
R-134a (215 g)
ISO10 (280 ml)
SHEATH HEATER
LED Module(24)
LED Module(12)
LED Module(12)
SPECIFICATIONS
LAMP
REFRIGERATOR
CONVERTA
FREEZER
DIMENSIONS
Depth w/ Handles
Depth w/o Handles
Depth w/o Door
Depth (Total with Door Open)
Height to Top of Case
Height to Top of Door Hinge
Width
Width (door open 90 deg. w/o handle)
Width (door open 90 deg. w/ handle)
A
B
C
D
E
F
G
H
I
35 3/8 in
32 7/8 in
29 in
47 5/8 in
68 3/8 in
69 3/4 in
35 3/4 in
39 1/4 in
44 1/4 in
Description LMX28994**
●28 cu.ft.

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2. PARTS IDENTIFICATION
!
#
$
$

"
"
ADJUSTABLE REFRIGERATOR SHELVING
1
The refrigerator compartment shelves are adjustable to
allow flexibility for storage needs.
GALLON STORAGE BINS
2
Two interchangeable bins can be arranged to suit your
storage needs.
REMOVABLE ICE STORAGE BIN
3
The ice storage bin can be removed to fill ice buckets,
coolers, or pitchers.
LED INTERIOR LAMPS
4
Three separate LED arrays light the freezer and
refrigerator interiors.
CAN STORAGE BIN
5
FIXED DOOR BINS
6

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3. DISASSEMBLY
3-1 REMOVING AND REPLACING REFRIGERATOR DOORS
●Removing Refrigerator Door
CAUTION: Before you begin, unplug the refrigerator. Remove food and bins from doors.
▶Left Door -FIG. 2
1. Disconnect water supply tube by pushing back on the disconnect ring (3).-FIG. 1
2. Open door. Loosen top hinge cover screw (1).
Use flat tip screwdriver to pry back hooks on front underside of cover (2). Lift up cover.
3. Disconnect door switch wire harness and remove the cover.
4. Pull out the tube.
5. Disconnect all 3 wiring harnesses (4). Remove the grounding screw (5).
6. Rotate hinge lever (6) counterclockwise. Lift top hinge (7) free of hinge lever latch (8).
7. Lift door from middle hinge pin and remove door.
8. Place the door with the insides facing up, on a not scratch surface.
CAUTION: When lifting hinge free from the latch, be careful that door does not fall forward.
▶Right Door -FIG. 3
1. Open the door, remove 1 screw on the top of the hinge cover. Loosen top hinge cover screw (1). Lift up cover (2).
2. Disconnect wire harnesses and remove the cover.
3. Rotate hinge lever (3) clockwise. Lift top hinge (4) free of hinge lever latch (5).
4. Lift door from middle hinge pin and remove door.
5. Place the door with the insides facing up, on a not scratch surface.
CAUTION: When lifting hinge free from the latch, be careful that the door does not fall forward.
Correct Incorrect
  
! " #
Figure 2 Figure 3
Figure 1
1) Insert the tube until you can see only one of
the lines printed on the tube.
2) After inserting, pull the tube to ascertain that
it is secure.
3) Assemble clip.

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1. Remove gasket
Pull gasket free from gasket channel on the four
remaining sides of door.
3-2 DOOR
●Mullion Removal
1. Remove 2 screws.
●Door Gasket Removal
2. Lift Mullion up carefully.
3. Disconnect wire harness.
●Door Gasket Replacement
1. Insert gasket into channel
Press gasket into channels on the four remaining
sides of door.
2. Insert mullion into the channel.
Insert the cover assembly into bracket, door.
●Mullion Replacement
1. Connect wire harness.
3. Assemble 2 screws.

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(1) (2)
(3) (4)
3-3 Door Alignment
If the space between the door are uneven,
follow the instructions to align them.
Remove the Base Grillie. Turn the leveling legs counter
clock wise to raise or clock wise to lower the height of the
front of the refrigerator by using flat blade screw driver or
11/32" wrench. Use the wrench (Included with the User
Manual) to adjust the bolt in the door hinge to adjust the
height. (CCW to raise or CW to lower the height.)
3-4 GRILLE ASSEMBLY
1. Remove the converta drawer. (See p. 14)
2. Remove the center plate by removing 2 screws and pull
the center plate.(1),(2)
3. Lift the front of the barrier up and remove the
harness.(3),(4)
4. Remove the freezer drawer. (See p.16)
5. Remove the guide rail of the converta drawer.
(Each guide rail has one harness.) (5),(6)
6. Remove the guide rail of the freezer drawer.
(Each guide rail has one harness.) (7),(8)
7. Using the tool like the thick wrench pull on the grille
assembly to remove.(9),(10)
8. Disconnect the wiring harnesses.
(5) (6)
(7) (8)
(9) (10)
3-5 FAN AND FAN MOTOR
1. Remove the Fan Motor assembly by loosening 3 screws.
2. Pull out the fan and separate the FAN Motor and
Bracket.
FAN MOTOR
BRACKET
MOTOR
Shroud

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1. Unplug refrigerator power cord form outlet.
2. Remove screw with driver.
3. Grasp the cover Lamp, pull the cover downward.
3-7-2 Converta and Freezer Compartment Lamp
3-8 MULTI DUCT
1. Romove the upper and
lower caps with a flat
screwdriver and remove
2 screws.
(Figure 3)
2. Disconnect the lead wire
on the bottom position.
Figure 3
3-7 LAMP
Unplug, or disconnect power at the circuit breaker.
If necessary, remove top shelf or shelves.
1) Release 2 screws.
2) Hold both ends and pull down to remove.
3-7-1 Refrigerator Compartment Lamp
4) Use a flat tool as shown below to remove the lamp
cover.
5) To remove the LED assembly, pull apart the cover.
Cover, lamp
Case, lamp
LED, Assembly
3) To remove the lamp case and cover, release 2 screws
as shown.
3-6 DEFROST CONTROL ASSEMBLY
Defrost Control assembly consists of Defrost Sensor and
FUSE-M.
The Defrost Sensor works to defrost automatically. It is
attached to the metal side of the Evaporator and senses its
temperature. At 46F(8°C), it turns the Defrost Heater off.
Fuse-M is a safety device for preventing over-heating of
the Heater when defrosting.
1. Pull out the grille assembly. (Figure 1)
2. Separate the connector with the Defrost Control
assembly and replace the Defrost Control assembly after
cutting the Tie Wrap. (Figure 2)
Figure 1 Figure 2
GRILLE ASSEMBLY DEFROST-CONTROL
ASSEMBLY

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3-9 MAIN PWB
1) Loosen 3 screws on the PWB cover.
3-10 DISPENSER
1) Pull out the drain 2) Use these 2 holes to pull
out the bottom
4) Holding the inner side of
the dispenser pull
forward to remove.
2) Remove the PWB cover
3) Disconnect wire harness and replace the main PWB in
the reverse order of removal.
3-11 ICE BUTTON ASSEMBLY
1) Remove the 1 screw holding the lever.
2) Remove the spring from the hook.
3) Push and pull on the tab to remove.
CAUTION: When replacing the dispenser cover make
sure the lead wire does NOT come off and the water line
is not pinched by the dispenser.
Button Lever
5) Remove the
lead wire.
3) If nozzle is interfered with button, push and pull out the
bottom of button and then pull out the right side.

- 10 -- 10 -
3-13 ICE CORNER DOOR REPLACEMENT
1) Loosen the front screw as shown in the picture.
2) Lift up the hinge with one hand.
3) Pull out the Ice Corner Door with the other hand.
3-12 WATER BUTTON ASSMEBLY
1) Remove screws.
2) Grasp the Button assembly and lift.
Button Lever
hinge
3-14 ICEMAKER REPLACEMENT
1) Remove 4 screws as shown.
2) Grasp the bottom of motor cover assembly and pull
slowly.
3) Disconnect wire harness from wall of compartment.
In-door
motor

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3-16 CAP DUCT MOTOR REPLACEMENT
1) Separate the Housing of the Cap Duct Motor.
3) When replacing the motor, check the position of the door
duct and the link for proper fit.
Link
Duct Door
Cap Duct Motor
NG Position
2) Unscrew 3 screws to disassemble the motor.
4) Insert 2 screws.
5) Push housing aside.
3-15 SUB PWB FOR WORKING DISPENSER
1) Disconnect the wire harness.
2) Remove 1 screw from PWB and replace with new PWB.
CAUTION: Make sure that the motor housing is taped to
the mold, if not positioned correctly the cover will not fit
properly.

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3-17 HOW TO REMOVE A ICE BIN
1) Grip the handles, as shown.
2) Tilt and lift slightly as shown.
3-18 HOW TO INSERT A ICE BIN
1) Insert the Ice Bin, slightly tilting to avoid touching the
Icemaker. (Especially, Ice-Detecting Sensor)

3) Remove ice bin slowly.

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3-19 HOW TO REPLACE THE CONVERTA DISPLAY
3-19-1 Disassembly
1) Attach tape PETP on the door.
(Lower part of display. To protect Scratch)
3-19-2 Assembly
1) Connect lead wire from display
2) Pre-Assemble display’s top portion department
3) Assembly display;s side portion department
4) Detach tape PETP
3) Disconnect lead wire from display.
2) Disassemble display’s lower portion to using tool.

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3-20 HOW TO REPLACE THE CONVERTA JOINT
1) Open the Converta drawer.
2) Remove the drawer.
4) Remove the Auto Drawer Joint Housing
5) Remove screws of Guide rail(each one in the both side).
6) Lift the door to disassemble.
3) Remove the motor cover.
8) Pull out rail to disassemble in pressing the rail stopper.
7) Using any sharp things such as drill, take out the gear in
pressing the right rail clip.
Clip

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9) Take it out after disassembling the Holder rail screws
(3 pcs).
10) Take it out by pressing the hook of auto drawer joint
housing by hands.
14) Pull out the auto drawer joint to the outside by using the
rear hole.
15) For reassembly, perform the disassembly procedures
in reverse.
11) Pull out the Holder rail inner link by hands.
13) Pull out the support holder to the rear hole.
- Pull out the stopper part strongly.
12) Take off the Holder rail fix connector.
Supporter Holder Hole
Stopper

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3-21
HOW TO REPLACE THE AUTO DRAWER MOTOR
1) Open the door of F room.
2) Remove the Drawer.
3) Remove screws of Guide rail.(Each one in the both side)
4) Lift the door to disassemble.
5) Remove the motor cover.
6) Remove the Auto Drawer Joint Housing, then separate
holder lever.
7) Using any sharp things such as drill, take out the gear in
pressing the right rail clip.
Clip

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9) Remove the Auto Drawer Motor screws (2 pcs).
10) For reassembly, perform the disassembly procedures
in reverse.
8) Take out the gear in the bar, and then bar in the motor. 3-22
HOW TO REPLACE THE AUTO DRAWER JOINT
1) Remove the Converta drawer(See p.)
2) Remove the center plate and barrier.(See p.)
3) Open the F door.
4) Remove the drawer.
5) Remove screws of guide rail. (each one in the both side)
6) Lift the door to disassemble.
7) Remove the motor cover.

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8) Remove the auto drawer joint housing, then separate
holder lever.
9) Using any sharp things such as drill, take out the gear in
pressing the right rail clip.
Clip
10) Pull out rail to disassemble in pressing the rail stopper.
11) Remove the guide rail screws
(each guide rail has 5 screws.)
12) Remove the harness.

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16) Pull out the auto drawer joint to the outside by using the
rear hole.
17) For reassembly, perform the disassembly procedures
in reverse.
13) Pull out the Holder rail inner link by hands. 15) Pull out the support holder to the rear hole.
- Pull out the stopper part strongly.
Supporter Holder Hole
Stopper
14) Take off the Holder rail fix connector.

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3-23 WATER VALVE DISASSEMBLY METHOD
1) Turn off the water to unit. Remove the waterline from the
valve.
3-24 FAN AND FAN MOTOR DISASSEMBLY
METHOD
1) Remove screws for the Drain Pipe Assembly and the 1
connected to the Motor Cover.
2) Remove cover and 1 screw from the valve.
3) Separate the housing and remove the valve.
4) Remove the clip, and press the collet to separate the
tube from the connector. Note: there maybe some water
in the line.
Mechanical Cover
Housing
MOTOR COVER
2) Separate the Fan Assembly and Motor, turn counter
clockwise to remove from the motor shaft.
FAN ASSEMBLY MOTOR
Assemble in reverse order. Taking care to avoid.
1. Do not to bend the tube during assembly.
2. Press the Water Dispenser button letting water pour out,
this checks for any leaks in the tube connection, this may
vary depending on the water pressure
( about 2 minutes.).
Figure 59
Figure 60
Figure 61
Figure 62
Figure 63
Figure 64