LG LMX28983ST Installation guide

TRAINING MANUAL LMX28983ST
LMX28983ST Page 1 FOUR DOOR REFRIGERATOR
IMPORTANT SAFETY NOTICE
The information in this training manual is intended for use by persons possessing an adequate background in
electrical equipment, electronic devices, and mechanical systems. In any attempt to repair a major appliance,
personal injury and property damage can result. The manufacturer or seller maintains no liability for the
interpretation of this information, nor can it assume any liability in conjunction with its use. When servicing this
product, under no circumstances should the original design be modified or altered without permission from LG
Electronics. Unauthorized modifications will not only void the warranty, but may lead to property damage or user
injury. If wires, screws, clips, straps, nuts, or washers used to complete a ground path are removed for service, they
must be returned to their original positions and properly fastened.
CAUTION
To avoid personal injury, disconnect the power before servicing this product. If electrical power is required for
diagnosis or test purposes, disconnect the power immediately after performing the necessary checks. Also be aware
that many household appliances present a weight hazard. At least two people should be involved in the installation
or servicing of such devices. Failure to consider the weight of an appliance could result in physical injury.
ESD NOTICE
Some of the electronic components in appliances are electrostatic discharge (ESD) sensitive. ESD can weaken or
damage the electronics in these appliances in a manner that renders them inoperative or reduces the time until their
next failure. Connect an ESD wrist strap to a ground connection point or unpainted metal in the appliance.
Alternatively, you can touch your finger repeatedly to a ground connection point or unpainted metal in the
appliance. Before removing a replacement part from its package, touch the anti-static bag to a ground connection
point or unpainted metal in the appliance. Handle the electronic control assembly by its edges only. When
repackaging a failed electronic control assembly in an anti-static bag, observe these same precautions.
REGULATORY INFORMATION
This equipment has been tested and found to comply with the limits for a Class B digital device, pursuant to Part
15 of the FCC Rules. These limits are designed to provide reasonable protection against harmful interference when
the equipment is operated in a residential installation. This equipment generates, uses, and can radiate radio
frequency energy, and, if not installed and used in accordance with the instruction manual, may cause harmful
interference to radio communications. However, there is no guarantee that interference will not occur in a particular
installation. If this equipment does cause harmful interference to radio or television reception, which can be
determined by turning the equipment off and on, the user is encouraged to try to correct the interference by one or
more of the following measures: Reorient or relocate the receiving antenna; Increase the separation between the
equipment and the receiver; Connect the equipment to an outlet on a different circuit than that to which the
receiver is connected; or consult the dealer or an experienced radio/TV technician for help.
DISCLAIMER
The information in this training manual was accurate at the time of publication. Every effort has been made to
ensure accuracy. Updates, changes, etc. are available via GCSC and LGCSacademy. The information in this manual is
intended for persons with adequate backgrounds in electronics, mechanical, and electronic servicing. The
manufacturer and seller are not to be held responsible for any liability incurred from its use.
COMPLIANCE
The responsible party for this device’s compliance is LG Electronics Alabama, Inc.; P O BOX 240007, Huntsville, AL,
35813.

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Contents
Important Notices (The Small Print Page) 1
Contents 2
Specifications 5
Dimensions 5
Parts Identification 6
Installation 7
Water Line Connection 8
Connecting the Water Line 9
Flooring Requirements 10
Handle Removal 10
Water Tube Connection 11
Door Removal 11
Door Heater Assembly 14
Refrigerator Door Switch 15
Freezer Door Switch 15
Door Gasket Removal 17
Door Gasket Replacement 18
Door Self-Closing Mechanism 19
Pullout Freezer Drawe
r
20
Defrost Control, Evapo
r
ator, and Fan Motor (Freezer) 23
Multi-Duct (Refrigerator) 27
Lamp (LED Array) 28
Damper (Air duct from freezer) and Moto
r
28
Pantry Damper (Meat, Deli, and Produce) 30
Icemake
r
31
Icemaker Compartment and Door 32
Water Filte
r
34
Icemaker (Test) 35
Cube Size Setting 36
Test Mode 36
Malfunction Indicato
r
36
Dispense
r
37
Auger Motor and Solenoid 39
Low-voltage Board (Dispenser) 39
High-voltage board (Dispenser) 39
Water Valves 40
Compresso
r
41
PTC (Positive Temperature Coefficient) 41
OLP (Overload Protector) 41
continued on next page Æ

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Contents, continued
Troubleshooting Chart (with error codes) 42
Schematic 43
Wire / Color / Circuit Scheme 43
Troubleshooting Flow Charts 44
Freezer Sensor Erro
r
44
Refrigerator Sensor Error 45
Defrost Sensor Erro
r
46
Icemaker Compartment Sensor Erro
r
47
Pantry Sensor Erro
r
48
Defrost Heater Erro
r
49
Freezer Fan Erro
r
51
Condenser Fan Erro
r
52
Icemaker Compartment Fan Erro
r
53
Refrigerator Fan Erro
r
54
Communication Erro
r
55
Cube Mode Fails 57
Crush Mode Fails 60
Water Mode Fails 62
Not Enough Ice or No Ice 64
Freezer LED Module Fails 66
Refrigerator LED Module Fails 68
Poor Cooling In Refrigerato
r
70
Overcooling In Refrigerato
r
74
Terminal Protectors (Assembly, Disassembly, and Testing) 75
Test Mode 77
Fan Error Test 78
Master Troubleshooting Chart 79
Exploded Views 84
Parts List 91
Touch-up Paint 97
Temperature Resistance Cha
r
t97
Serial Number Identification 98
Supplementary Materials 99
Ohm’s Law and Watt’s Law 99
Temperature Conversion Information (°C / °F) 100
Service Bulletins 101
Ver. 1.2 090814

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NOTES

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SPECIFICATIONS
ITEM SPECIFICATION ITEM SPECIFICATION
Door Design Rounded Sides Vegetable Tray Clear Drawe
r
Dimensions (in.) 35¾ X 35⅜X 69¾ Compresso
r
Reciprocal
Net Weight 359 lbs. (163 kg) Evaporato
r
Fin Tube Type
Cooling System Fan Forced Ai
r
Condense
r
Wire Type
Insulation Polyurethane Foam Refrigerant R-134a (150 g)
(5.29 oz.)
Door Finish Embossed Stainless Compressor Oil ISO10 (280 ml)
Handle Type Ba
r
Inner Case ABS Resin
Defrost System Full Automatic
Defrost Heater
Defrost System Sheath Heate
r
Temperature
Control
Microprocessor
Controlled
Lamp (Ref.)
(Fr.)
LED module (24)
LED Module (12)
DIMENSIONS
DESCRIPTION LMX28983ST
Depth with handles A 35⅝“
Depth without handles B 32⅞”
Depth without doo
r
C 29”
Depth (total, with door open) D 47⅝”
Height (to top of case) E 68⅜”
Height (to top of door hinge) F 69¾”
Width G 35¾”
Width (door open to 90°without handle) H39¾”
Width (door open to 90°with handle) I44¼”

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PARTS IDENTIFICATION
The 28 cubic foot LMX28983ST fou
r
-
door refrigerator, with a two-drawer
freezer compartment, a two-door
(French door) refrigerator compartment,
and an in-door ice and water dispenser.
nAdjustable Refrigerator Shelving
for flexible storage needs
oGallon Storage Bins
for milk and other refreshments
pRemovable Ice Storage Bin
for storing extra ice and for
serving
qLED Interior Lamps
for bright, even illumination
rSHORT’N’TALL Bin
Flexible storage for handy
storage of often-used items
sFixed Door Bin
Flexible storage for handy
storage of often-used items

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INSTALLATION
WEIGHT HAZARD!
The refrigerator weighs as much as 359 pounds (163 kg). We recommend a minimum of two
people for moving and servicing this refrigerator.
LEVELING
Be sure the floor is level and strong enough to support the refrigerator. Unstable installation or
unleveled flooring may cause vibration, noise, and poor door operation. Be sure to level the
refrigerator at installation using the height adjusting screws (leveling legs.)
If the base grille (kick plate) is installed,
remove it by removing the two screws that
hold it on.
When the refrigerator is in place, adjust
the leveling legs by turning them
counterclockwise to raise or clockwise to
lower the refrigerator.
Use an
11
/
32” (8 mm) wrench to turn the
hex ends of the leveling bolts or stick a flat
screwdriver in the slots to turn them. If you
have a helper to push against the top of
the refrigerator and take the weight off the
leveling legs, you can turn them by hand.
Be sure to lower them enough to contact
the floor and support some of the weight
of the refrigerator. It will keep it from
moving when you pull the doors open and
from tipping forward when the freezer
drawer is pulled out.
Replace the base grille.

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WATER LINE CONNECTION
Read ALL the directions thoroughly before you begin. Be certain you understand all the
requirements for installing and connecting a water connection for this refrigerator.
WARNING! Connect the water supply tube from the refrigerator to a potable water supply only.
The water pressure requirement for this refrigerator is 43 ~121 psi (3 ~8.5 kgf/cm2). If the
existing pressure is insufficient, the customer can purchase a separate pressure pump to provide
normal icemaking and water dispensing operation.
•The total length of the water supply line should not be greater than 26 feet
(8 meters.)
•Use copper tubing or a braided, reinforced nylon supply line.
•Install the water line in an area where the temperature will not drop below freezing.
•It may take up to 24 hours for the icemaker to begin producing ice.
The icemaker water valve includes a flow washer that functions as a water pressure regulator.
TOOLS REQUIRED
Standard screwdriver ¼” nut driver
7/16” open-end wrench ½” open end wrench
¼” drill bit drill (electric drills must be grounded)
WATER LINE INSTALLATION KIT
Some dealers sell an installation kit that includes all the parts necessary to connect the
refrigerator to a water line. Often, these kits include a piercing saddle-type valve that allows
connection to the water line without the need for plumbing skills. LG does not recommend the
use of this type valve because it often fails to provide sufficient water flow for the icemaker and
dispenser to function properly.
continued on next page

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Various connector types are available.
These illustrations show a saddle valve
with the water line connected using a
compression fitting at each end.
LG does not recommend the use of this
type valve because it often fails to provide
sufficient water flow for the icemaker and
dispenser to function properly.
The additional coil of tubing (approx-
imately 7 feet or 2.1 m) is to allow pulling
the refrigerator out for servicing or
cleaning.
We recommend the use of a pre-assembled
braided plastic or nylon line with threaded
couplings on both ends to prevent leakage
and pop offs.
CONNECTING THE WATER LINE
The best solution is to use a braided reinforced nylon supply line with screw-on fittings on both
ends. These allow the simplest and easiest connection with fewer leaks and problems. If you
don’t use this type connection, we recommend using a flare nut wrench to connect the water line
fittings. After the valve has been installed on the water line, it must be flushed before connecting
it to the refrigerator. Remove the plastic cap from the water valve on the back of the refrigerator.
Attach the water supply line to the valve. Open the valve and flush out the supply line before
attaching it to the refrigerator. Attach the supply line to the water valve on the back of the
refrigerator. Tighten all connections. Turn on the water and check for leaks. Press the water
dispenser button and bleed all the air through the system. When water begins coming out, run
another quart to be sure all the air is out of the line. Turn the icemaker on and cycle it manually
until water fills the tray to ensure all the air is out of the line.

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FLOORING REQUIREMENTS
The refrigerator must be installed on a solidly constructed floor to minimize noise and vibration.
The refrigerator must be level. If necessary, adjust the leveling legs under the front of the
refrigerator to compensate for variations in the flooring. This is easier if the refrigerator is tipped
slightly backward to take the weight off the legs. Turn them clockwise to raise the refrigerator or
counterclockwise to lower it.
Never install the refrigerator on a platform or a weakly supported structure.
When moving the refrigerator for cleaning or service, be sure to protect the floor. Pull the
refrigerator straight out. Do not walk or wiggle it; floor damage or side panel damage may occur.
HANDLE REMOVAL
It may be necessary to remove the handles
to get the refrigerator through a door.
Loosen the set screws with a 3/32”
(2.5 mm) Allen wrench.
Remove the handle.
If the mounting bolts require removal or
adjustment, use a ¼” Allen wrench.
Use extreme caution when removing the
handles to avoid scratching the doors.
When you remove or replace a handle,
push (or pull) firmly but do not damage the
handle or the door by using excessive
force.
Replace the handles by placing the handles
on the mounting bolts and tightening the
set screws.

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WATER TUBE CONNECTION
The water tube connections must be properly assembled to avoid leaking.
Insert the tube into the connector until
only one of the printed lines is visible.
Pull on the tube slightly to ensure proper
insertion and retention. Insert the retainer
clip under the release ring.
If you can see both rings, the tube is not
inserted properly. The tube end must be
cut squarely.
DOOR REMOVAL
If the refrigerator is in use, be sure to remove all food and door bins. Unplug the refrigerator and
turn off the water. When the doors are removed, place them on blankets or padded surfaces to
prevent damage.
Do not put your hands, feet, fingers, or metal (conductive) items into the air vents, the base
grille (kick plate), or bottom of the refrigerator. You could be injured or shocked.
If the entrance door is too small to accommodate the refrigerator, you can remove the doors
and pull the refrigerator into the room sideways.

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Follow these steps to remove and replace the refrigerator doors. Refer to the drawings above.
RIGHT DOOR
Open the door to 90°.
Remove the top hinge cover (1) screw.
Lift the cover (2).
Disconnect the wire (3) harness.
Rotate the hinge lever (4) clockwise and
remove it.
Lift the top hinge (5) clear of the hinge
lever latch (6).

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LEFT DOOR
Disconnect the hose at the top right
corner (facing the back) by removing the
release clip and pressing the release ring.
The tube will be pulled out with the door
when it is removed.
Open the door to 90°.
The door must be opened to 90°to be
removed or reattached.
Remove the screw (1) securing the top
hinge cover.
Use a flat screwdriver to pry off (2) the
hinge cover. (Hooks not shown.)
Remove the cover and pull the (3) water
tube through.
Disconnect all the wiring (4) harnesses.
Remove the ground (5) screws.
Turn the hinge lever (6) counter-clockwise
and remove it.
Lift the top hinge (7) free of the latch
lever (8).
Be careful the door does not fall forward.
With the door open to 90°, lift it off the
middle hinge pin.

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DOOR HEATER ASSEMBLY
The doors have heaters on the opening
edge; that is, the edges that face each
other in the center of the refrigerator.
These small, 2-watt heating elements keep
condensation from forming along the
opening where cold air escapes when the
doors are open.
The heater is foamed into the door
assembly, so the only way to replace the
heater is to replace the entire door.
To check the continuity of the door heater
circuit, unplug the 6-pin connector at the
top of the door hinge.
Pins 2 and 3 have no connection.
Pins 1 and 4 – Infinity
(Brown and yellow)
Pins 1 and 5 – Infinity
(Brown and red)
Pins 1 and 6 – 1.8 kΩ
(Brown and white)
NC – No Connection

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REFRIGERATOR DOOR SWITCH
Remove the switch from its housing by
pressing the tabs on either end of the
switch and pulling it out. Disconnect it
from the wiring harness.
The door switches determine whether the
doors are opened or closed. When a door
is opened, the appropriate interior lighting
is switched on by the microprocessor,
which also operates various fans and
dampers.
Check the resistance between terminals
1 and 2, and between terminals 3 and 4.
With the switch plunger pushed in, there
should be infinite resistance. With the
plunger released, there should be 0 Ω
resistance.
FREEZER DOOR SWITCH
Remove the switch from its housing by
pressing the tabs on either end of the
switch and pulling it out. Disconnect it
from the wiring harness.
The door switches determine whether the
doors are opened or closed. When a door
is opened, the appropriate interior lighting
is switched on by the microprocessor,
which also operates various fans and
dampers.
Check the resistance between terminals
1 and 2, and between terminals 3 and 4.
With the switch plunger pushed in, there
should be infinite resistance. With the
plunger released, there should be 0 Ω
resistance. It is simply two single pole
single throw switches.

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The normally closed (NC) Upper Freezer
Door Monitor 5v Orange to Orange
Connects to black and sky blue (BK and
SB) at CON 6 Pins 5 and 6 on the main
board.
With the switch pressed, orange to orange
should show infinite resistance. (Door
closed, switch open, light off.)
With the switch pressed, white/blue tracer
to yellow should show infinite resistance.
(Door closed, switch open, light off.)
The normally closed upper freezer door
switch should read infinite resistance
across blue/white tracer (12 VDC) and the
yellow wire connects to the red (Freezer
LED module.)

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DOOR GASKET REMOVAL
Remove the door frame cover. Starting at
the top of the cover and working down,
snap the cover out and away from the
door.
Remove the gasket bracket clips. There are
two clips per door. Start the bracket
removal near one of the clips.
Pull the gasket back to expose the clip and
the door frame.
Insert a flat-tipped screwdriver into the
seam between the gasket and the door
frame and pry back until the clip snaps
back.
Continue prying back along the seam until
all the clips snap out.
Pull the gasket free from the channel along
the edge of the door. Don’t pull at the
corners to avoid tearing the seams.

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DOOR GASKET REPLACEMENT
Insert the gasket bracket clips beneath the
door frame edge.
Turn the upper gasket bracket spring so
the spring ends are in the door channel.
Push the clip until you hear it snap securely
into place.
Push the remaining clip until you hear it
snap securely into place.
Snap the gasket into the door bracket.
Be sure it is aligned properly. The
alignment is incorrect in this drawing.
DOOR ALIGNMENT
If the space between the doors in uneven,
remove the kick plate and adjust the
leveling legs. Turn the legs with a
screwdriver or an 11/32” wrench.
Use the small wrench (included with the
instruction manual) to adjust the bolt in
the door hinge.

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DOOR CLOSER
The refrigerator doors have automatic
closing mechanisms built into the hinge.
To remove it, remove the two screws on
the base plate of the hinge.
(The right hinge is shown; the left is
similar.)
Remove the end screw that holds the hinge
in the door.
Pull the closing mechanism out of the door.
Replacement is the opposite of these
steps.

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PULLOUT FREEZER DRAWER
Open the drawers (one at a time) and
remove the bins or baskets.
Remove the two screws from the guide rails
(one from each side.)
Lift the freezer door up to unhook it from
the rail support and remove.
Pull both rails to full extension.
Remove the gear from the left side first by
releasing the tab behind the gear, place a
screwdriver between the gear and the tab
and pull up on the gear.
Remove the center rail.
Remove the gear from the right side by
following the same steps for the left side.
NOTE: THIS TAB MUST BE PUSHED IN
TO RELEASE THE GEAR.