LG LSC27990TT User manual

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REFRIGERATOR
SERVICEMANUAL
CAUTION
PLEASEREADCAREFULLYTHE SAFETYPRECAUTIONSOF THIS MANUAL
BEFORECHECKINGOR OPERATINGTHE REFRIGERATOR.
MODEL : LSC27990TT COLOR :TITANIUM

CONTENTS
WARNINGS AND PRECAUTIONS FOR SAFETY ................................................................................................................ 3
SPECIFICATIONS ................................................................................................................................................................... 4
PARTS IDENTIFICATION ........................................................................................................................................................ 5
HOW TO INSTALL THE REFRIGERATOR ............................................................................................................................ 6
HOW TO ADJUST DOOR HEIGHT ...................................................................................................................................... 6
FILTER ................................................................................................................................................................................. 7
HOW TO CONTROL THE ICEMAKER WATER SUPPLY .................................................................................................... 8
MICOM FUNCTION ................................................................................................................................................................ 9
EXPLANATION OF MICOM CIRCUIT ................................................................................................................................... 22
EXPLANATION OF PWB CIRCUIT ..................................................................................................................................... 22
PWB PARTS DIAGRAM AND LIST ..................................................................................................................................... 37
PWB CIRCUIT DIAGRAM ................................................................................................................................................... 43
ICEMAKER AND DISPENSER WORKING PRINCIPLES AND REPAIR ............................................................................ 45
WORKING PRINCIPLES .................................................................................................................................................... 45
FUNCTION OF ICEMAKER ............................................................................................................................................... 46
CIRCUIT ................................................................................................................................................................................ 48
TROUBLE DIAGNOSIS ........................................................................................................................................................ 49
TROUBLESHOOTING ....................................................................................................................................................... 49
FAULTS .............................................................................................................................................................................. 59
COOLING CYCLE HEAVY REPAIR ................................................................................................................................... 76
HOW TO DEAL WITH CLAIMS .......................................................................................................................................... 83
TV-RADIO ............................................................................................................................................................................. 88
SAFETY PRECAUTIONS ................................................................................................................................................... 88
FEATURE ........................................................................................................................................................................... 88
CONTROLS ........................................................................................................................................................................ 89
REMOTE CONTROL KEY FUNCTIONS ........................................................................................................................... 90
TROUBLESHOOTING ....................................................................................................................................................... 91
BLOCK DIAGRAM .............................................................................................................................................................. 92
TV PART DISASSEMBLE .................................................................................................................................................. 93
HOW TO DISASSEMBLE AND ASSEMBLE ....................................................................................................................... 94
DOOR ................................................................................................................................................................................. 94
HANDLE ............................................................................................................................................................................. 95
FAN SHROUD GRILLE ...................................................................................................................................................... 95
WATER VALVE DISASSEMBLY METHOD ......................................................................................................................... 96
FAN and FAN MOTOR DISASSEMBLY METHOD .............................................................................................................. 96
DISPENSER ....................................................................................................................................................................... 97
EXPLODED VIEW ................................................................................................................................................................ 99
REPLACE PARTS LIST ....................................................................................................................................................... 106
-2-

WARNINGS AND PRECAUTIONS FOR SAFETY
Please observe the following safety precautions to use the
refrigerator safely and correctly and to prevent accident or
injury when servicing.
1. Be careful of an electric shock. Disconnect the power
cord from wall outlet and wait for more than three
minutes before replacing PWB parts. Shut off the power
whenever replacing and repairing electric components.
2. When connecting the power cord, please wait for more
than five minutes after the power cord was disconnected
from the wall outlet.
3. Check if the power cord is pinched between the
refrigerator and the wall. If the plug or cord is damaged,
it could cause a fire or an electric shock
4. If the wall outlet is overloaded, it may cause a fire. Use a
dedicated circuit for the refrigerator.
5. Make sure the outlet is properly grounded.
Particularly in a wet or damp area.
6. Use standard electrical components.
7.Remove dust and foreign materials from the housing and
connecting parts.
8. Do not fray, damage, run over, kink, bend, pull out, or
twist the power cord.
9. Check for evidence of moisture intrusion in the
electrical components. Replace the parts or mask with
insulation tape if moisture intrusion was confirmed.
10. Do not insert fingers or tools into the icemaker. The
geared motor drive could cause an injury or damage to
tools or the icemaker.
11. De not suggest that customers repair their refrigerator
themselves. This work requires special tools and
knowledge. Non-professionals could cause fire, injury,
or damage to the product.
12. Do not store flammable materials such as ether,
benzene, alcohol, chemicals, or gas.
13. Do not put anything on top of the refrigerator,
especially something containing water, like a vase.
14. Do not put glass bottles with full of water into the
freezer. The contents will freeze and break the glass
bottles.
15. When you scrap or discard the refrigerator, remove the
doors and dispose of it where children are not likely to
play in or around it.
16. This is a consumer grade product. It is not intended for
precise storage of medication.
-3-

SPECIFICATIONS
1. Ref No. : GR-G277STSA(LSC27990TT)
ITEMS
DIMENSIONS
WxDxH
NET WEIGHT
COOLING SYSTEM
TEMPERATURE CONTROL
DEFROSTING SYSTEM
INSULATION
COMPRESSOR
EVAPORATOR
CONDENSER
REFRIGERANT
LUBRICATING OIL
SPECIFICATIONS
908x 896 x 1771mm
(3511/16x355h6x69W16in.)
145kg (319.7 Ibs.)
Fan Cooling
Micom Control
Full Automatic
Heater Defrost
Cyclo-Pentane
PTC Starting Type
Fin Tube Type
Wire Condenser
R134a (185g) (61/2oz.)
FREOL @10G (320 cc)
ITEMS
DRIER
CAPILLARY TUBE
FIRST DEFROST
DEFROST CYCLE
DEFROSTING DEVICE
ANTI-SWEAT HEATER
ANTI-FREEZING HEATER
FREEZER LAMP
REFRIGERATOR LAMP
DISPENSER LAMP
SPECIFICATIONS
MOLECULAR SIEVE XH-7
ID a0.83
4 - 5 Hours
13 - 15 Hours
Heater, Sheath
Dispenser DuctDoor Heater
Dispenser Heater
Water Tank Heater
Damper Heater
40W (1 EA)
40W (4 EA)
15W (1 EA)
t-
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Ob
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E
F--
I,,.,.
I
t- t-
_o _o
E E
E E
i.q i.q
•r- ,r-
_c
k
,r-
1004 mm (391/2 in.) .
908 mm (3911/16 in.)
co
LO LO
o oJ
CO CO
v v
E E
E E
Ob Ob
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I',--. (3o
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LO CO
Lo Ob
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Front View Top View
-4-

PARTS IDENTIFICATION
1. Ref No. : GR-G277STSA(LSC27990TT)
PWB Cover
\\\,_
Frame Display
Dis
Ice &
Dispenser Button
L_ ............. '}i!l]J!iili
c? _ ===
Water Tubes
/.- /
Automatic
Icemaker
Freezer
Compartment Refrigerator Compartment Dairy Product Corner
Water Filter
Lamp
Shelf
Lamp
Shelf
Drawer
Door Rack
Drawer
Door Rack
Shelf
Snack Drawer
-- Door Rack
Lamp
Bottle Guide
Vegetable Drawer
OptiFresh
Door Rack
Lower Cover ...............................................................-// OptiFresh Display Humidity Switch
-5-

HOW TO INSTALL REFRIGERATOR
1. How to Adjust Door Height of Refrigerator
• Make the refrigerator level first. (If the refrigerator is not installed on a flat floor, the height of freezer and refrigerator
door may not be the same.)
1) If the freezer door is lower than the refrigerator
door: 2) If the freezer door is higher than the refrigerator door:
i I
I
t
IScrew
I
\\ Driver
Insert a driver _ into the groove Oof the adjusting
screw and turn in the direction of the arrow (clockwise)
until the refrigerator is level.
Insert a driver _ into the groove O if the adjusting screw
and turn in the direction of the arrow (clockwise) until the
refrigerator is level.
3) When the refrigerator door is lower than the freezer door
Adjust the level when the refrigerator door is lower than the
freezer door during
the use of the refrigerator.
(1) Using the wide side of the tool for adjustment O, turn the
keeper nut O('_'_) clockwise to loosen the keeper nut.
(2) Using the narrow side of the tool for adjustment, turn the
adjustment hinge pin _ (,_,_) clockwise or (_V')
counterclockwise to level the refrigerator and freezer door.
(3) After setting the level of the door, turn the keeper nut (_v)
counterclockwise to tighten.
Caution : Do not force too hard to level the height. The hinge
pin can be pulled out (Adjustable range of height:
Maximum of 2/10 " (5 mm)).
i O Keeper nut
(2_Adjustment
hi_ _ge pin
,'a)Tool for
adjustment
Up
!>J
-6-

HOW TO INSTALL REFRIGERATOR
2. Filter
Replace the filter when the indicator light comes on or the
performance of the icemker or water dispenser decreases
noticeably.
2) Replace with a new cartridge.
Take the new cartridge out of its packaging and remove
protective cover from the o-rings.
With cartridge knob in the vertical position, push the new
filter cartridge into the cover until it stops.
After changing the water filter cartridge, reset the water
filter status display and indicator light by pressing and
holding the FILTER Button for 3 seconds. (page 13)
1) Remove the old cartridge.
Twist the knob of the cartridge counterclockwise.
If you can't turn the filter from side to side, it isn't fully
inserted. Push it in firmly and twist it into place. You will
hear the snap when it clicks into place.
Using the handle, twist the cartridge clockwise about 1/4
turn. /
When the cartridge is removed, you will feel it click.
Pull out the cartridge.
NOTE: There will be some water (25cc) in the filter
cartridge. Some spilling may occur. Catch it in a
bowl or towel.
3) Flush the Water System After Replacing Filter
Dispense water through the water dispenser for 3
minutes to purge the system.
There may be a little air in the line, causing noise or
hissing. Run the water at the dispenser until the hissing
stops to purge the air from the system.
NOTE: - To purchase replacement water filter cartridges,
visit your local appliance dealer or part distributor.
-You can also visit our website :
www.lgappliances.com or call 1-877-714-7481.
LG MDL PART NO MAKER
GR-G277STSA 5231JA2006A CUNO
(LSC27990TT)
-7-

HOW TO INSTALL REFRIGERATOR
3. How to Control the Amount of Water Supplied to Icemaker.
3-1. Confirm the amount of water supplied to the icemaker.
1) Confirm the amount of water supplied to the icemaker
(1) Press the button (Figure 1) to selsct the level of water (Optimum level --* Large -=, Small.)
2) Icemaker Operation Test (Test mode)
(1) Press the button (Figure 1) for more than 3 seconds and It will start the Test mode.
(2) Test the operation of the operating part of the icemaker.
(3) If there is no problem with the operation, water is supplied through the water tube (up to the
selected lebel of water).
(4) The test mode is completed after the water is supplied.
Note : When using the test mode more than twice consecutively, water can overflow.
When the water overflows, wipe the ice storage bin.
Check water level
Water Amount
Indicator Light
_po Feeler
wer Arm
1.........// Water Amount Switch
Selection Button
Figure 1.
* It is acceptable if the adjusted level of water is a bit smaller than optimum level.
-8-

MICOM FUNCTION
1. Monitor Panel
1-1. GR-G277STSA(LSC27990TT)
Temperature Adjust Button -Calendar &
oe OSe,ect,oo u, ooJ/ Dispenser Selection Button ' I'
Lock Button Door Alarm Button
Dispenser Light Button
-9-

MICOM FUNCTION
1-2. Display Second Function
LCD Check Mode
Demo Mode
ICommunication Data Check Mode Door Alarm Buzzer
Mute Mode
1. Door Alarm Buzzer Mute Mode
Press _))) _ button to the buzzer on or off.
2. Demo Mode
Demo mode is available for displaying the refrigerator in a sales setting or similar condition.
It allows the display, dispenser, lights, and fan to operate without running the compressor.
To enter the DEMO mode, press and hold the TEMPERATURE and _ I_ button simultaneously for 5 seconds until the
Ding- sounds in the lock status.
To exit the DEMO mode and return to normal operation, press and hold the TEMPERATURE and _ I_1 button
simultaneously for 5 seconds until the Ding- sounds again in the lock status.
The refrigerator will default to the NORMAL mode (DEMO mode OFF) if the power fails.
2. LCD Check Mode
Press TEMPERATURE and I_)))_, button simultaneously for 1 second in the lock status.
4. Communication Data Check Mode
Press MENU and -',0_ button simultaneously for 6 seconds in the lock status.
-10-