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REFRIGERATOR SERVICE MANUAL CAUTION BEFORE SERVICING THE UNIT, READ THE SAFETY PRECAUTIONS IN THIS MANUAL. MODELS: LRFC22750SW LRFC22750SB LRFC22750ST...
CONTENTS C o n te n ts … … … … … … … … … … … … … … … … … … … … … … … … … S a fe ty P re c a u tio n s … … … … … … … … … … … … … … … … … … … … . S p e s ific a tio n s …...
1. SPECIFICATIONS 22 cu. Ft. (22.4 cu. Ft.) ITEMS SPECIFICATIONS ITEMS SPECIFICATIONS DOOR DESIGN Side Rounded VEGETABLE TRAY Opaque Drawer Type DIMENSIONS COMPRESSOR PTC Starting Type W(836)x D(870)x H(1754) mm W(32.91)x D(34.25)x H(69.06) i n EVAPORATOR Fin Tube Type CONDENSER Wire Condenser 127.5 Kg NET WEIGHT...
2. PARTS IDENTIFICATION Digital Sensor Control* Filter (inside)* Refrigerator Light Dairy Bin Shelves Egg Box Chef Fresh Design-A-Door Bins Can Dispenser Freezer Light Optibin Crisper Wire Basket Keeps fruits and vegetable fresh and crisper Customcube Icemaker Ice Bin Full Widht Wire Basket Wire Durabase *On some models - 4 -...
3. DISASSEMBLY 2. Remove gasket bracket clips 3-1 DOOR There are two clips on each door. Start bracket removal near one of the middle clips. Left Door 1) Pull gasket back to expose gasket bracket clip and Loosen the cover screw (1). door frame.
2. Insert gasket into channel 3-2 DOOR ALIGNMENT 1) Snap gasket assembly into the door bracket. If the space between your doors is uneven, follow the <Inserting the Gasket Assembly into the Bracket Door> instructions below to align the doors: 1.
3-3 FAN AND FAN MOTOR 3-5-1 Refrigerator Compartment Lamp 1. Remove the freezer shelf. (If your refrigerator has an 1. Unplug the power cord from the outlet. icemaker, remove the icemaker first) 2. Remove refrigerator shelves. 2. Remove the plastic guide for slides on left side by 3.
4. ADJUSTMENT 4-1 COMPRESSOR 4-2-3 PTC-Applied Circuit Diagram Starting Method for the Motor 4-1-1 Role The compressor intakes low temperature and low pressure gas from the evaporator of the refrigerator and compresses OVERLOAD PROTECTOR this gas to high-temperature and high-pressure gas. It then delivers the gas to the condenser.
4-3 OLP (OVERLOAD PROTECTOR) 4-4 TO REMOVE THE COVER PTC 4-3-1 Definition of OLP (1) OLP (OVERLOAD PROTECTOR) is attached to the Compressor and protects the Motor by opening the circuit to the Motor if the temperature rises and activating the bimetal spring in the OLP. (2) When high current flows to the Compressor motor, the Bimetal works by heating the heater inside the OLP, and the OLP protects the Motor by cutting off the...
6. TROUBLESHOOTING 6-1 COMPRESSOR AND ELECTRIC COMPONENTS (Rated Voltage Remove PTC-Starter Power Source. ±10%)? from Compressor and measure voltage between Terminal C of Compressor and Terminal 5 or 6 of PTC. OLP disconnected? No Voltage. Replace OLP. Check connection condition. Reconnect.
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6-2 PTC AND OLP Normal operation of Separate PTC-Starter Observation value is Compressor is from Compressor and 115V/60Hz : 6.8Ω±30% measure resistance impossible or poor. between No. 5 and 6 of PTC-Starter with a Tester. (Figure 19) Replace PTC- The resistance value Starter.
6-3 OTHER ELECTRICAL COMPONENTS M Not cooling at all Check for open short or Compressor Cause incorrect resistance readings doesn't run. in the following components a. Starting devices Short, open, or broken. Poor contact b. OLP or shorted. Coil open or shorted. c.
6-4 SERVICE DIAGNOSIS CHART COMPLAINT POINTS TO BE CHECKED REMEDY No Cooling. • Is the power cord unplugged from the outlet? • Plug into the outlet. • Check if the power switch is set to OFF. • Set the switch to ON. •...
6-5 REFRIGERATION CYCLE M Troubleshooting Chart TEMPERATURE STATE OF STATE OF THE CAUSE REMARKS OF THE THE UNIT EVAPORATOR COMPRESSOR PARTIAL Freezer Low flowing sound of A little higher • Refrigerant level is low due LEAKAGE compartment and Refrigerant is heard and than ambient •...
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6-5-1 SEALED SYSTEM DIAGNOSIS “Not Cooling” Complaint All components operating, No airflow problems, Not frosted up as a defrost problem problem has been isolated to sealed system area Frost None Partial Pattern? Equalization Equalization Test Test Very Fast Very Slow Very Slow Fast Very Fast...
7. OPERATION PRINCIPLE AND REPAIR METHOD OF ICEMAKER 7-1 OPERATION PRINCIPLE 7-1-1 Operation Principle of IceMaker Power On Start Position • Adjusts EJECTOR to Start Position with power on. Ice Making • Waits until water becomes cold after starting the Mode ice making operation.
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7-2 ICE MAKER FUNCTIONS 7-2-1 Start Position 1. After POWER OFF or Power Outage, check the EJECTOR's position with MICOM initialization to restart. 2. How to check if it is in place: - Check HIGH/LOW signals from HALL SENSOR in MICOM PIN. 3.
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7-2-4 Fill / Park Position 1. Once a normal harvest mode has been completed, the water solenoid will be activated. 2. The amount of water is adjusted by pressing the Fill Key repeatedly. This changes the time allowed for fill as illustrated in the table below.
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7-2-5 Function TEST 1. This is a compulsory operation for TEST, SVC, cleaning, etc. It is operated by pressing and holding the Fill Key for 3 seconds. 2. The test works only in the Ice Making Mode. It cannot be entered from the Harvest or Fill mode. (If there is an ERROR, it can only be checked in the TEST mode.) 3.
8 WATER FILTER 8.1 WATER FILTER CARTRIDGE REPLACEMENT FILTER (on some models) Pull out the cartridge. It is recommended that you replace the filter when the water filter indicator light turns on or your water dispenser or ice maker decreases noticeably. After changing the water filter cartridge, reset the water 4.
Turn the shutoff valve on (house valve).* Flush water out from the system until air gets eliminated and water start to dispense (approximately for 60 seconds NOTE: T o purchase replacement water filter cartridges, visit your local appliance dealer or part distributor. You can also visit our website : www.lgappliances.com or call &...
9. DESCRIPTION OF FUNCTION & CIRCUIT OF MICOM 9-1 FUNCTION 9-1-1 Function 1. When the appliance is plugged in, it is set to 37°F for Refrigerator and 0°F for freezer. You can adjust the Refrigerator and the Freezer control temperature by pressing the ADJUST button. 2.
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9-1-6 Alarm for Open Door 1. This feature sounds a buzzer when the freezer or refrigerator door is not closed within 1 minute after it is opened. 2. One minute after the door is opened, the buzzer sounds three times each for 1/2 seconds. These tones repeat every 30 seconds.
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9-1-9 Electrical Parts Are Turned On Sequentially Electrical parts such as COMP, defrosting heater, freezer FAN, etc. are turned on in the following order to prevent noise and parts damage. Several parts are started at the same time at initial power on and are turned off together when TEST is completed.
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9-1-10 Defect Diagnosis Function 1. Automatic diagnosis makes servicing the refrigerator easy. 2. When a defect occurs, the buttons will not operate; but the tones. such as ding. will sound. 3. When the defect CODE removes the sign, it returns to normal operation (RESET). 4.
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9-1-11 TEST Mode 1. The Test mode allows checking the PCB and the function of the product as well as finding out the defective part in case of an error. 2. The test mode is operated by pressing two buttons at Display panel. 3.
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9-2 PCB FUNCTION 9-2-1 Power Circuit The secondary part of the TRANSFORMER is composed of the power supply for the display, the BLDC FAN Motor drive (15.5 V), the relay drive (12 Vdc) and the MICOM and IC (5 Vdc). The voltage for each part is as follows: PART VA 1...
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9-2-2 Oscillation Circuit This circuit generates the base clock for calculating time and the synchro clock for transmitting data from and to the inside logic elements of the IC1 (MICOM). Be sure to use specified replacement parts, since calculating time by the IC1 may be changed.
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9-2-4 Load / Buzzer Drive & Open Door Detection Circuit 1. Load Drive Condition Check 5mH/4A 470nF 275VAC CON1 POWER ICE MAKER RUNNING CAPACITOR CON2 COMP STARTING CAPACITOR ALZ21B12 KID65003AP PTC START 1N4004 COOLING-FAN G5NB-1A DEF-HEATER FUSE-M G5NB-1A LAMP-F DOOR S/W-F G5NB-1A LAMP-R I C 1...
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part part part MOTOR OFF 2V or less MOTOR ON 13V~15V 2V~3V 2.2 Cooling motor driving circuit (machine room) 1. This circuit makes standby power 0 by cutting off power supplied to ISs inside of the fan motor in the fan motor OFF . 2.
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3. Open Door Detection Circuit Check Measurement Location Freezer/ (PIN NO.30 & PIN NO.37) Refrigerator Door Closed Open 9-2-5 Temperature Sensor Circuit The upper CIRCUIT reads REFRIGERATOR temperature, FREEZER T emperature, 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...
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9-2-6 Refrigeration Compartment Stepping Motor Damper Circuit * The circuit shown below is the damper circuit to regulate the refrigerator temperature. 9-2-7 Dispenser Input - 33 -...
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9-2-8 Temperature Compensation & Overcooling/Undercooling Compensation Circuit 1. Refrigerator Temperature Compensation ➧ Table of Temperature Compensation by adjusting the Refrigerator resistance (difference from the current temperature) Resistance Temperature Remark e.g., If the refrigerator compensation resistance (RCR) Compensation (RCR) is changed from 10K (the current resistance) to 18K (the adjustment resistance), the temperature 180 KΩ...
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9-5-3 PWB Assembly, Display, And Parts List CON102 WORK P/NO DESCRIPTION SPEC MAKER REMARK 6870JB8199A PWB(PCB) BRAVO 33 DISPLAY YEON HO 6630JB8005C CONNECTOR (CIRC), WAFER SMAW250-04 CON01 TOSHIBA 0IZZJB????? IC, DRAWING TMP87C409M 28, SOP28-P-450 BRAVO 33 MITSUBISHI 0ISTLM1001A IC, STANDARD LOGIC M54563FP MITSUBISHI 20 R/TP CONVERT 0IKE650030C IC, KEC...
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9-2-9 Key Button Input & Display Light-On Circuit The circuit shown above determines whether a function control key on the operation display is pushed. It also turns on the corresponding function indication LED Module SEVEN SEGMENT DISPLAY . The drive type is the scan type. CON 6 - 36 -...
9-5-2 Replacement Parts List P/NO DESCRIPTION SPEC MAKER REMARK 6870JB8203A PWB(PCB) BEST BRAVO-PJT DOO SAN T=1.6 6170JB2012B TRANSFORMER,SMPS[COIL] DL-PJT 2.9MH/20W SAM IL TRANS 6170JB2012C TRANSFORMER,SMPS[COIL] TRANS 6630AQ9106D CONNECTOR (CIRC),WAFER YW396-09AV YEON HO CON1 6630AQ9106E CONNECTOR (CIRC),WAFER YW396-07AV YEON HO CON2 6630AQ9106B CONNECTOR (CIRC),WAFER YW396-05AV...
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#EV# 10 .EXPLODED VIEW & REPLACEMENT PARTS LIST CASE PARTS CAUTION: Use the part number to order part, not the position number. 103B 281A 402A 271C 282E 103A 410A 402A 409D 501F 503G 271A 903D 503D 610A 282F 503C 503E 501A 409B 120B...
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#EV# FREEZER PARTS CAUTION: Use the part number to order part, not the position number. 285A 145C 136A 248F 136D 131C 136B 248A 136E 248F 131A 136G 128D 136C - 45 -...
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#EV# REFRIGERATOR PARTS CAUTION: Use the part number to order part, not the position number. 147C 147B 141D 147A 149C 141A 149E 141B 141E 140A 141C 140B 140F 103E 128A 142A 142D 142B 142E 128B 103E 103E 146A 128A 170A 103E 128M 128G...
#EV# DOOR PARTS CAUTION: Use the part number to order part, not the position number. 230B 230A 104E 231B 233B 233C 231A 233D 233D 233A 241A 241B 212G 241C 147D 244G 244G 241C 244B 244B 244D 241C 244D 700C 700C 241C 244E 244E...
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#EV# ICE MAKER PARTS CAUTION: Use the part number to order part, not the position number. 602A 600A - 48 -...
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#EV# ICE & WATER PARTS CAUTION: Use the part number to order part, not the position number. 622A 618A 619C 616E 623C 619A 619B 627B 262D - 49 -...
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#EV# PART NUMBER BY MODEL LOC ITEM DESCRIPTION LRFC22750SW LRFC22750SB LRFC22750ST 103A HANDLE,BACK izq 3650JJ2003E 3650JJ2003L 3650JJ2003L 103B HANDLE,BACK der 3650JJ2003A 3650JJ2003M 3650JJ2003M 103C COVER ASSEMBLY,LOWER 3551JJ1015B 3551JJ1015F 3551JJ1015F 103E RAIL,SLIDE 5218JJ3001A 5218JJ3001A 5218JJ3001A 103E RAIL,SLIDE 5218JJ3001A 5218JJ3001A 5218JJ3001A 103E RAIL,SLIDE...
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#EV# PART NUMBER BY MODEL LOC ITEM DESCRIPTION LRFC22750SW LRFC22750SB LRFC22750ST 145A HOLDER,SHELF 4930JJ2003A 4930JJ2003A 4930JJ2003A 145B HOLDER,SHELF 4930JJ2004A 4930JJ2004A 4930JJ2004A 145C GUIDE ASSEMBLY,RAIL 4975JJ1001C 4975JJ1001C 4975JJ1001C 146A CAN,SERVER 5044JJ1001A 5044JJ1001A 5044JJ1001A 146B CONNECTOR ASSEMBLY (MECH) 5098JJ2002H 5098JJ2002B 5098JJ2002H 146C CONNECTOR ASSEMBLY (MECH)
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#EV# PART NUMBER BY MODEL LOC ITEM DESCRIPTION LRFC22750SW LRFC22750SB LRFC22750ST 244G STOPPER,HANDLE 4620JJ3007B 4620JJ3007B 4620JJ3007B 245A HOLDER,HANDLE 4930JJ2019E 4930JJ2019C 4930JJ2019B 245B HOLDER,HANDLE 4930JJ2020E 4930JJ2020C 4930JJ2020B 248A RAIL ASSEMBLY,SLIDE 5219JJ1002D 5219JJ1002D 5219JJ1002D 248F SUPPORTER,HOLDER 4980JJ2005A 4980JJ2005A 4980JJ2005A 262D CLIP 4004JA3002A...
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#EV# PART NUMBER BY MODEL LOC ITEM DESCRIPTION LRFC22750SW LRFC22750SB LRFC22750ST 404A MOTOR ASSEMBLY,REF FAN 4681JK1004A 4681JK1004A 4681JK1004A 405A BRACKET ASSEMBLY,MOTOR 4811JJ2002A 4811JJ2002A 4811JJ2002A 405B RUBBER,MOTOR-N 5040JJ2001A 5040JJ2001A 5040JJ2001A 405C RUBBER,MOTOR-F 5040JA2009B 5040JA2009B 5040JA2009B 405F RUBBER,MOTOR-F 5040JA2004B 5040JA2004B 5040JA2004B 405G BRACKET ASSEMBLY,MOTOR...
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