background image

6-4 SERVICE DIAGNOSIS CHART

- 14-

COMPLAINT

POINTS TO BE CHECKED

REMEDY

•Other possible problems:

Check if frost forms in
the freezer.

Check Components
of the defrosting
circuit.

Check the
refrigeration system.

Check the 
Thermistor.

Not
defrosting

The system
is faulty.

Perform sealed
system repair.

Replace the
Thermistor.

The operation of
the Thermistor is
incorrect.

No Cooling.

Cools poorly.

Food in the
Refrigerator
is frozen.

Condensation or ice
forms inside
the unit.

Condensation forms
in the Exterior Case.

There is abnormal
noise.

Door does not
close well.

Ice and foods
smell unpleasant.

• Is the power cord unplugged from the outlet?

 Check if the power switch is set to OFF.
 Check if the fuse of the power switch is shorted.
 Measure the voltage of the power outlet.

 Check if the unit is placed too close to the wall.
 Check if the unit is placed too close to the stove, 

gas cooker, or in direct sunlight.

 Is the ambient temperature too high or 

the room door closed?

 Check if food put in the refrigerator is hot.
 Did you open the door of the unit too often 

or check if the door is sealed properly?

 Check if the Control is set to 

Warm position

.

 Is food placed in the cooling air outlet?

 Check if the control is set to 

colder position

.

 Is the ambient temperature below 5ºC?

 Is liquid food sealed?
 Check if food put in the refrigerator is hot.
 Did you open the door of the unit too  

often or check if the door is sealed properly?

 Check if the ambient temperature and humidity

of the surrounding air are high.

 Is there a gap in the door gasket?

 Is the unit positioned in a firm and even place?

 Are any unnecessary objects placed 

in the back side of the unit?

 Check if the Drip Tray is not firmly fixed.
 Check if the cover of the compressor enclosure 

in the lower front side is taken out.

 Check if the door gasket is dirty with 

an item like juice.

 Is the refrigerator level?

 Is there too much food in the refrigerator?

 Check if the inside of the unit is dirty.
 Are foods with a strong odor unwrapped?
 The unit smells of plastic.

 Plug into the outlet.
 Set the switch to ON.
 Replace the fuse.
 If the voltage is low, correct the wiring.

 Place the unit about 4 inches (10 cm) from the wall.
 Place the unit away from these heat sources.

 Lower the ambient temperature.

 Put in foods after they have cooled down. 
 Don't open the door too often and close

it firmly.

 Set the control to 

Recommended position

.

 Place foods in the high-temperature section.

(front part)

 Set the control to 

Recommended position

.

 Set the control to 

Warm position

.

 Seal liquid foods with wrap.
 Put in foods after they have cooled down.
 Don't open the door too often and close

it firmly.

 Wipe moisture with a dry cloth. It will disappear

in low temperature and humidity.

 Fill up the gap.

 Adjust the Leveling Screw, and position the 

refrigerator in a firm place.

 Remove the objects.

 Fix the Drip Tray firmly in the original position.
 Place the cover in its original position.

 Clean the door gasket.

 Position in a firm place and level the

Leveling Screw.

 Make sure food stored in shelves does not prevent 

the door from closing.

 Clean the inside of the unit.
 Wrap foods that have a strong odor.
 New products smell of plastic, but this 

will go away after 1-2 weeks.






















Summary of Contents for LFC20740 Series

Page 1: ...CAUTION BEFORE SERVICING THE UNIT READ THE SAFETY PRECAUTIONS IN THIS MANUAL REFRIGERATOR SERVICE MANUAL MODELS LFC20740 ...

Page 2: ...efrigerator should be performed by a Qualified technician Sealed system repair must be Performed by a CFC certified technician SAFETYPRECAUTIONS SAFETY PRECAUTIONS 1 SPECIFICATIONS 2 PARTS IDENTIFICATION 3 DISASSEMBLY 3 1 DOOR 3 2 DOOR ALIGNMENT 3 3 FAN AND FAN MOTOR 3 4 DEFROST CONTROL ASSEMBLY 3 5 LAMP 3 6 REFRIGERATOR CONTROL BOX 3 7 MULTI DUCT 4 ADJUSTMENT 4 1 COMPRESSOR 4 2 PTC STARTER 4 3 OL...

Page 3: ... PAN YES 1 SHELF 4fIX MAGIC CRISPER NO LAMP YES 2 TRAY EGG GUIDE BOTTLE YES 2 TRAY VEGETABLE NORMAL NO REFRIGERATOR BASKET DOOR 3 LEFT 3RIGHT REFRIGERANT gr MODELS SPECIFICATIONS LFC20740 180 97 374 23 555 20 29 7 8 68 3 7 34 5 9 111 R134a 120 3gr NO FREEZER ICE TRAY GENERAL FEATURES SHELF CAPACITY litros F R T DIMENSIONS in W H D WEIGHT kg ...

Page 4: ...elow The locations of the features shown below may not match your model on some models A B C G H I J E F K D L M N O P A L Digital Sensor Control Durabase Divider Egg Box Refrigerator Door Rack Freezer Light Pull out Drawer B C D F E G H I J K M N O P Ice Tray Optibin Crisper Keeps fruits and vegetable fresh and crisper Snack Pan Can Dispenser Temperature Control Shelves Refrigerator Light Customc...

Page 5: ...ce 4 Push in remaining two clips until you hear each snap securely into place Note Make sure that no part of gasket bracket edge protrudes from beneath door frame edge 3 DISASSEMBLY 5 Frame Cover Handle Gasket Door Bracket Clip Frame Flat Tip Screwdriver Gasket Bracket Figure 3 Figure 1 Figure 2 Figure 4 Gasket Bracket Clip Spring Door Frame Correct Incorrect Figure 5 Left Door Loosen the cover sc...

Page 6: ... cover and working down snap cover back into door 3 2 DOOR ALIGNMENT If the space between your doors is uneven follow the instructions below to align the doors 1 With one hand lift up the door you want to raise at middle hinge 2 With other hand use pliers to insert snap ring as shown 3 Insert additional snap rings until the doors are aligned Three snap rings are provided with unit 6 Figure 6 Corre...

Page 7: ...ator light figure 14 Max 60 W2EA 3 5 2 Freezer Compartment Lamp figure 15 1 Unplug refrigerator or disconnect power 2 Reach behind light shield to remove bulb 3 Replace bulb with a 60 watt appliance bulb 4 Plug in refrigerator or reconnect power 3 6 CONTROL BOX REFRIGERATOR 1 First remove all shelves in the refrigerator than remove the Refrigerator control Box by loosening 2 screws 2 Remove the Re...

Page 8: ... the start winding and main winding 4 2 3 PTC Applied Circuit Diagram Starting Method for the Motor 4 2 4 Motor Restarting and PTC Cooling 1 It requires approximately 5 minutes for the pressure to equalize before the compressor can restart 2 The PTC device generates heat during operation Therefore it must be allowed to cool before the compressor can restart 4 2 5 Relation of PTC Starter and OLP 1 ...

Page 9: ...e OLP in any way 4 4 TO REMOVE THE COVER PTC 1 Remove the Cover Back M C 2 Disconnect two housing upper side of comp connected in 3 Loosen two screws on comp base 4 Use a L shaped flap tool to pry off the cover 5 Assembly in reverse order of disassembly 9 Part Customer part number Lot code date code 330 FBYY S1 BOX98 12345678 Physical termination part number Electrical characteristics part number ...

Page 10: ...5 CIRCUIT DIAGRAM 10 ...

Page 11: ...ly needs to be checked by an electrician Replace Compressor Supply voltage rating with 10 Applied voltage isn t in acceptable range 115V 10 Remove PTC Starter from Compressor and measure voltage between Terminal C of Compressor and Terminal 5 or 6 of PTC Check resistance between M C S C and M S in Motor Compressor Check resistance of two terminals in PTC Starter Check resistance of two terminals i...

Page 12: ...ure resistance between No 5 and 6 of PTC Starter with a Tester Figure 19 Separate OLP from Compressor and check resistance value between two terminals of OLP with a Tester Figure 20 Observation value is 115V 60Hz 6 8Ω 30 The resistance value is 0Ω short or open Check another electric component Replace OLP Replace PTC Starter Figure 19 Figure 20 ...

Page 13: ...apacity Replace indicated component Advise customer that the Power supply needs to be checked by an electrician Replace indicated component Cause Check voltage at starting devices Check current flowing in sub coil of Compressor Check rating of OLP Fan motor doesn t run Heavy frost buildup on EVAPORATOR Wire is open or shorted Coil is shorted or open Open Open Replace Defrost Heater Replace indicat...

Page 14: ...igh Is there a gap in the door gasket Is the unit positioned in a firm and even place Are any unnecessary objects placed in the back side of the unit Check if the Drip Tray is not firmly fixed Check if the cover of the compressor enclosure in the lower front side is taken out Check if the door gasket is dirty with an item like juice Is the refrigerator level Is there too much food in the refrigera...

Page 15: ...tor don t in inlet only temperature The capillary tube is faulty cool normally WHOLE Freezer Flowing sound of refrigerant Equal to ambient Normal discharging of the CLOG compartment and is not heard and frost isn t temperature Refrigerant Refrigerator don t cool formed MOISTURE Cooling operation Flowing sound of refrigerant Lower than Cooling operation restarts CLOG stops periodically is not heard...

Page 16: ...ial Very Fast Inefficient Compressor Partial Restriction Complete Restriction Equalization Test Condenser Temperature None Very Fast Very Slow Very Slow Hotter than Normal Air Low Side Leak Loss of Change Compressor Not Pumping Cap Tube Sound Room Temperature Trace of Oil Undercharge Leak Yes No Faint Fast None to Weak The equalization test is trying to restart a compressor using a start kit after...

Page 17: ...e Park Position Fill Test Mode Waits until water becomes cold after starting the Icemaking operation Runs MOTOR to drop ice from the tray into the ICE BIN Performs Icemaking Mode after supplying water by operating the SOLENOID in ICE VALVE To operate LINE and SERVICE press and hold the Cube Size button for 3 seconds The icemaking will run through 3 stages Harvest Fill Icemaking With the detect lev...

Page 18: ...ed if it reaches start position again while Heater Motor are on at the same time A ice bin is full The EJECTOR stops heater off B ice bin is not full The EJECTOR rotates twice to open for ice NOTE If the EJECTOR does not rotate once within 5 minutes in status 2 separate heater control mode starts operating to prevent the EJECTOR from being constrained It is recommended that the user open for ice t...

Page 19: ...r supply control panel ERROR indicators in table can be checked only in TEST mode STAGE ITEMS INDICATOR REMARKS 1 2 3 4 5 6 HEATER MOTOR HALL IC TRAY SOLENOID VALVE HALL IC LEVER Reset Five seconds after heater starts heater will go off if temperature recorded by sensor is 10 C 50 F or lever is in up position Five seconds after heater starts you can confirm that motor is moving You can confirm Hal...

Page 20: ...n again ICE PLUS function will be canceled 4 To activate these function you need to press the ICE PLUS key and the LED will turn ON This function will remain activated for 24 hrs The first three hours the compressor and ICE PLUS will be ON The next 21hours the freezer will be controlled at the lowest temperature After 24 hours or if the ICE PLUS key is pressed again the freezer will return to its ...

Page 21: ...compressor running time reaches 4 hours 4 Defrosting stops if the sensor temperature reaches 46 4 F 8 C or more If the sensor doesn t reach 46 4 F 8 C in 2 hours the defrost mode is malfunctioning Circuit 8 1 9 5 Defrosting won t function if its sensor is defective wires are cut or short circuited 8 1 8 Electrical Parts Are Turned On Sequentially Electrical parts such as COMP defrosting heater fre...

Page 22: ...Connecting wires on each sensor Snapping of defrost heater or Temperature fuse pull out of Connector indicated minimum 2 Hours after failure occurs All off All off All off All off All off LED OFFLED ON 2 hours later after Open or short circuit Visible in LED CHECK MODE starting defrost If sensor doesn t be over 46ºF 8ºC 5 Failure of BLDC fan motor at freezing compartment DISPLAY CHECK MODE Press a...

Page 23: ... key and ADJUST key of refrigerator temperature control are pressed for more than 3 seconds at the same time temperature s it converts to demostration mode 2 In this status each LED is rotated with 1 second interval 3 In this status all Loads are off Compressor Fan Damper Heater Even is Demonstration Mode the refrigerator Lamp automatic off function works normally and can be demostrated 4 It reset...

Page 24: ... TRANSFORMER PART VA 1 CE 3 CE 4 CE 5 VOLTAGE 115 Vac 12 Vdc 15 5 Vdc 5 V 680J 470nF TEST 16V FB1 9 56KJ R5 CE1 R6 RL2 R8 D3SBA60 1J 1W 220 240V KIA431 8 5 50V CC4 1 2J 1W 115V 12 RL1 IC5 R7 22uF CC5 CM2 R3 221 4 CON1 Rocp CE2 D2 D3 CE5 BD1 15 5V 22 VA1 473 INR14D621 220 240V L2 IC4 560KJ 12V 17 IC3 FR107 G6351 4 R4 IC3 1 6 8KJ 1 2W 330KJ 1W 115V Vss 25V 150KJ 1W 220 240V 33J RL2 CC3 9 1KF 3 42 CM...

Page 25: ...ows 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 malfu...

Page 26: ...5 5 9 3 KID65003AP STARTING CAPACITOR 3 IC6 CON2 com FRENCH DOOR P04 G5NB 1A RY3 HEATER CON1 5 11 15 1N4004 LAMP R 1 VA1 1 5 RY1 INR14D621 220 240V 3 7 A COOLING FAN CON3 DOOR S W R1 R2 C RY4 M CM1 B D7 P07 RUNNING CAPACITOR G5SB 1A POWER ALE15B12 2 LAMP F com G5NB 1A 9 8 275VAC 60W 2 12 PTC START 1 nc 470nF DOOR S W F DEF HEATER P06 L1 13 nc 12 FUSE M 11 ICE MAKER D 60W 14 RY2 nc 9 5mH 4A COMP co...

Page 27: ...e up to 7 5V 16V to motor 3 This circuit prevents over driving the fan motor by cutting off power applied to the fan motor in the lock of fan motor by sensing the operation RPM of the fan motor R16 10KJ 2 FR107 R20 4 7KJ CC9 R17 D5 CC8 1mH P70 PDO PWM 2KJ Q2 KTB1151 4 1 R18 1 R19 P72 3 1 2W 220uF KTC3198 3 9KJ D6 25V INT3 TC3 R15 6 FR107 F FAN CE7 L3 R14 CON4 223 3 8 2 Q3 330J 1 5KJ 102 4 7KJ MICO...

Page 28: ...63 kz Beep OFF 0 05 s 0 1 s 0 2 s 2 s 0 V 5 V 0 V 5 V 2 63 kz Ding 2 21 kz Dong A B Tone Ding Dong when the button on the display is pushed Alarm for open door beep beep beep Pin No 11 12 Refrigerator Door Pin No 1 2 Freezer Door Closed 5 V Open 0 V Freezer Refrigerator Door Measurement Location 12 D 27 223 CC16 AIN4 R43 11 1 2 223 C 30 REFRIGERATOR DOOR SWITCH CON6 2KJ B R37 FREEZER DOOR SWITCH A...

Page 29: ...FREEZER SENSOR MICOM A B C The upper CIRCUIT reads REFRIGERATOR temperature FREEZER Temperature and DEFROST SENSOR temperature for defrosting and the indoor temperature for compensating for the surrounding temperature into MICOM OPENING or SHORT state of each TEMPERATURE SENSOR are as follows SENSOR CHECK POINT NORMAL 30 C 50 C SHORT CIRCUITED OPEN Freezer Sensor POINT Voltage Refrigerator Sensor ...

Page 30: ...mper Circuit The circuit shown below is the damper circuit to regulate the refrigerator temperature CE12 10 3 R47 10KJ P01 P03 STEPPING 13 B 12 13 6 8 7 14 50V IC10 4 11 P02 14 B 1uF TA7774AP 1 2 MOTOR 5 15 R45 4 5 7 10KJ A R46 10KJ A 9 16 15 6 CON4 MICOM ...

Page 31: ...R30 6 240 1 2W 7 P76 18 R24 17 6 3 P16 4 7KJ 5 240 1 2W 12 P21 7 P73 R28 11 9 10 8 3 32 36 6 6 19 R22 R29 39 P75 2 13 2 4 8 R23 18 P15 16 220 1 2W 10 5 4 7KJ P10 5 KID65003AP 2 1 4 R35 P20 100J 1 IC8 240 1 2W R21 3 KTC3198 4 17 31 8 11 4 7KJ 4 240 1 2W 33 34 4 7KJ P74 R26 20 1 P71 M54563FP P22 12 P13 5 1 13 13 8 P11 7 P12 R25 102 Q4 41 R31 IC6 1 P77 14 6 R32 5 P17 2KJ R36 CC10 9 240 1 2W 3 15 4 10...

Page 32: ...OR SUPER FROST SENSOR R1 R2 SENSOR after disconnect CON5 of PWB ASSY MAIN TEMPERATURE DETECTED RESISTANCE OF FREEZER RESISTANCE OF REFRIGERATOR BY SENSOR SENSOR DEFROST SENSOR ROOM SENSOR 20º C 15º C 10º C 5º C 0º C 5º C 10º C 15º C 20º C 25º C 30º C 40º C 50º C 22 3 K Ω 16 9 K Ω 13 0 K Ω 10 1 K Ω 7 8 K Ω 6 2 K Ω 4 9 K Ω 3 9 K Ω 3 1 K Ω 2 5 K Ω 2 0 K Ω 1 4 K Ω 0 8 K Ω 77 K Ω 60 K Ω 47 3 K Ω 38 4 K...

Page 33: ...C is poor Replace OLP PTC after compressor shuts off COMPRESSOR RELAY is Replace MAIN PWB don t press the KEY and poor wait THE CONNECTING WIRE Check the connection of the is poor black wire of the MAIN PWB CONNECTOR CON2 2 If refrigerant is leaking Measure the amount of frost Refrigerant leakage Replace the leaking part and sticking on EVAPORATOR replace any lost refrigerant and the surface tempe...

Page 34: ...liner damaged Replace Door liner door is closed DEFROSTING is NO DEFROSTING 1 If HEATER emits heat USE TEST MODE3 HEATER disconnection Replace HEATER poor forced DEFROSTING TEMPERATURE FUSE Replace TEMPERATURE disconnection FUSE Connection is poor Check EVAPORATOR connection and wire of MAIN PWB CONNECTOR DEFROST SENSOR is poor Replace DEFROST SENSOR HEATER RELAY is poor Replace RY2 of MAIN PWB 2 ...

Page 35: ...8 5 MAIN PWB ASSEMBLY AND PARTS LIST 8 5 1 Main PWB Assembly 35 ...

Page 36: ...CM4 CM4 APPLICATION APPLICATION CAPACITOR FIXED CERAMIC High dielectric CAPACITOR FIXED CERAMIC High dielectric 220 OHM 1 2 W 5 2012 R TP 220 OHM 1 2 W 5 2012 R TP 11 11 CAPACITOR FIXED ELECTROLYTIC CAPACITOR FIXED ELECTROLYTIC ORS3303J609 ORS3303J609 PILKOR PILKOR 25 25 78 78 CE2 CE2 RESISTOR FIXED METAL FILM RESISTOR FIXED METAL FILM 1 1 9 9 99 99 IC2 IC2 106 106 1 2 OHM 1 W 5 TA52 1 2 OHM 1 W 5...

Page 37: ...8 5 3 PWB Assembly Display and parts list 37 ...

Page 38: ... 1 2W 330KJ 1W 115V Vss 25V 150KJ 1W 220 240V 33J RL2 IC8 1 C 19 GND CC3 9 1KF RY4 3 42 M CM1 104 104 3 29 3 D1 B 2 D7 32mH 0 5A RL2 1KJ 1 R2 P07 1MJ 220uF 104 FR107 STR 2 RUNNING CAPACITOR G5SB 1A KIA7042 630V 21 POWER 10KJ ALE15B12 2 AIN6 20 LAMP F 47uF com G5NB 1A R10 1KJ 2 5V 250V 9 104 8 450V CC2 CM4 471 250V 2A 1 275VAC 60W 2 12 CE6 Varef TOSHIBA TMP87PH46N IC1 PTC START 1 D4 10 330uF 5 1 Va...

Page 39: ...NSOR 8 RD1 RT1 R43 REFRIGERATOR SENSOR 11 R40 F2 50V 4 7KJ 11 4 11 AIN3 1 240 1 2W 33 1 P02 R6 34 4 7KJ F6 3 R19 P60 P74 10uF P72 3 1 2W R26 220uF 20 1 P71 CE11 M54563FP P22 16 2KF KTC3198 12 2 14 3 9KJ FREEZER B D6 223 P13 1uF 25V C 10KF 5 FREEZING P61 1 30 TA7774AP 13 1 2 13 INT3 TC3 R15 MOTOR F5 8 P11 5 6 7 FR107 P12 R25 15 REFRIGERATOR DOOR SWITCH CON6 6 102 2KJ Q4 F FAN SW103 RF1 R45 4 5 7 10...

Page 40: ... 314A 307A 312A 317A 310A 103A 105A 301A 103B 418A 281A 402A 271C 305B 305B 305C 305C 323B 329C 420A 319A 319C 503D 282B 409D 120B 409B 158A 125D 332A 135C 405A 158E 145B 409B 503C 503E 106A 145A 282F 128F 128E 405C 405F 319E 329A 404A 903D 610A 903E 610A 262H 410G 402A 271A 282E 503G 503F 406B S22 405G 903A 903B 903B 103C 105F 410A 327A S01 S01 619B S38 328A EV 40 ...

Page 41: ...FREEZER PARTS CAUTION Use the part number to order part not the position number 136A 237C 136B 248E 248F 131A 145C 145F EV 41 ...

Page 42: ...t number to order part not the position number 146A 170A 128A 103E 103E 128B 143F 142E 142D S24 S24 140B 140B 140B 1 1 140E 140E 140D 140D 143E 143E S24 S24 S24 S24 EV 140B 1 140E 140D 143E S24 S24 103E 167B 154A 151A 151A 103E 155B 151C 42 ...

Page 43: ...4E 241C 241C 241C 237A 241C 241C 241C 241A 241F 241B 237A 250A 233B 233C 231B 230B 243A 243B 262E 233A 233D 231A 230A 212G 243A S27 243B 249J 249K 262E 286A 233D Only on some models 250B 249E 249A 621B 249F 249B 250B 621C 286A 212J 244A 212J 244A 212A 212J EV 205B 205C 233E 233F 233G 233H S27 43 ...

Page 44: ...WATER and ICE MAKER PARTS CAUTION Use the part number to order part not the position number 602A S28 600A 619A 619C 262 D 618A 616E 622A S31 S29 623C 622B 600C 627A EV 44 ...

Page 45: ...er 406B 6600JB1010A Switch Push Button 201A 5433JJ0059V Door Foam Assembly Freezer 409B 6912JB2004M Lamp Incandescent 203A 4987JJ1004G Gasket Assembly Door 409D 3034JJ1002B Reflector Lamp 205B 5006JJ2014A CAP COVER 410A 6621JK2002D Drawing Assembly 205C 5006JJ2014B CAP COVER 410G 0CZZJB2012J Capacitor Electric Appliance Film Box 212A 3651JA1033J Handle Assembly Freezer 411A 6411JK1006A Power Cord ...

Page 46: ...Button 200A 3581JJ8720K Door Assembly Freezer 409B 6912JB2004M Lamp Incandescent 201A 5433JJ0059S Door Foam Assembly Freezer 409D 3034JJ1002B Reflector Lamp 203A 4987JJ1004C Gasket Assembly Door 410A 6621JK2002D Drawing Assembly 205B 5006JJ2014A CAP COVER 410G 0CZZJB2012J Capacitor Electric Appliance Film Box 205C 5006JJ2014B CAP COVER 411A 6411JK1006A Power Cord Assembly 212A 3651JA1033K Handle A...

Page 47: ...P No 3828JL8076G JUNE 2007 ...

Reviews: