http://biz.lgservice.com REFRIGERATOR SERVICE MANUAL CAUTION BEFORE SERVICING THE UNIT, READ THE "SAFETY PRECAUTIONS" IN THIS MANUAL.
CONTENTS CONTENTS............................................................................................................................................................................. 2 SERVICING PRECAUTIONS.................................................................................................................................................. 3 SPECIFICATIONS.......................................................................................................................................
SERVICING PRECAUTIONS vacuum operation is over, add the quantity in grams of R-134a to the refrigerant system. Remember that every system has an exact quantity of R-134a with a tolerance of ±5 grams that can be added. (Figure 4) Air Recharging in Compressor Test the refrigeration by connecting it electrically before refilling operation. It is necessary to ascertain the function of the motor-compressor and identify the defects immediately.
1. SPECIFICATIONS 1-1 GR-S552 ITEMS FREEZER SPECIFICATIONS ITEMS 114 SPECIFICATIONS FREEZER 1 EA REFRIGERATOR 2 EA SHELF NET CAPACITY REFRIGERATOR (l) TOTAL 306 420 VEGETABLE TRAY Drawer Type DIMENSIONS (mm) 755(W)X689(D)X1777(H) EGG TRAY 2 Pieces NET WEIGHT (kg) 79 ICE TRAY 2 Pieces (Plastic) COOLING SYSTEM Fan Cooling ICE BANK 1 Piece TEMPERATURE CONTROL Micom Control COMPRESSOR P.T.
2. PARTS IDENTIFICATION 2-1 FEATURE CHART FREEZER COMPARTMENT Lamp Shelf Freezer Temperature Control Dial Twisting Ice Serve(Option) or General Type Ice Making Freezer Door Rack REFRIGERATOR COMPARTMENT Egg Storage Rack Deodorizer Refrigerator Temperature Electronic Control Fresh Meat Lamp Shelves Vegetable Drawer Used to keep fruits and vegetables, etc. fresh and crisp. Leveling Screw Base Cover NOTE : This is a basic model. The shape of refrigerator is subject to change.
3. DISASSEMBLY 3-1 DOOR 3-2 DOOR SWITCH ● Freezer 1. To remove the door switch, pull out it with a '—' type driver as shown in (figure 9). 2. Disconnect the lead wire from the switch. Door 1. Remove the hinge cover by pulling it upwards. 2. Loosen hexagonal bolts fixing the upper hinge to the body and lift the freezer door. HINGE COVER BOLT HINGE Figure 9 Figure 6 3-3 FAN AND FAN MOTOR 3. Pull out the door gasket to remove from the door foam Ass'y. 1. Remove the freezer shelf. 2.
3-5-1 Freezer room lamp 1. Unplug the power cord from the outlet. 2. Remove the room lamp lid by taking down while pulling it forward with your hand after inserting finger into the inside hole as shown in (figure 16). 3. Remove the lamp by turning it counterclockwise. 4. Assemble in reverse order of disassembly. Replacement bulb must be the same specication as original. 3-4 DEF' CONTROL ASSY Def control ASM consists of Defrost Sensor and FUSE–M.
4. ADJUSTMENT 4-2-3 PTC-Applied Circuit Diagram ● According to Starting Method of Motor 4-1 COMPRESSOR 4-1-1 Role The compressor inhales low temperature and low pressure gas evaporated from Evaporator of the Refrigerator, and condenses this gas to high temperature and high pressure gas, and then plays delivering role to Condenser.
4-3 OLP (OVER LOAD PROTECTOR) CONTACTING POINT 4-3-1 Definition of OLP (1) OLP (OVER LOAD PROTECTOR) is attached to Hermetic Compressor and protects Motor by cutting off current in Compressor Motor by Bimetal in the OLP in case of over-rising temperature. (2) When over-voltage flows to Compressor motor, Bimetal works by heating the heater inside OLP, and OLP protects Motor by cutting off current which flows to Compressor Motor.
6. TROUBLESHOOTING 6-1 COMPRESSOR AND ELECTRIC COMPONENTS 1 Power Source. Remove the PTC-Starter from the Compressor and measure the voltage between Terminal C of Compressor and Terminals 5 or 6 of PTC. (Rating Voltage ±10%)? No Voltage. OLP disconnected? YES 2 YES Replace OLP. 5 Check connection condition. Reconnect. Advise the customer to use a regular Trans. Applied voltage isn't in the range of Rating Voltage ±10%. 2 3 Check the resistance of Motor Compressor.
6-2 PTC AND OLP Observation value is 220V/50Hz : 47Ω ± 30% 220 - 240V/50Hz : 47Ω ± 30% 110 -115V/60Hz : 6.8Ω ± 30% 220V/60Hz : 47Ω ± 30% 127V/60Hz : 22Ω ± 30% Separate the PTC from Compressor and measure the resistance between No. 5 and 6 (only RSIR Type) or No. 4 and 5 of PTC with a Tester or Whistone Bridge. (Figure 22) The resistance value is 0 or several hundreds Ω. The value is ∞. Separate the OLP from Compressor and check resistance value between two terminals of OLP with a Tester.
6-3 ANOTHER ELECTRIC COMPONENTS ▼ Cooling is impossible Compressor doesn't run. Running state of Compressor is poor. Check if current flows to the following components. Cause. a. Thermistor Poor contacting. b. Starting devices Shorted or broken. c. OLP Poor contacting or shorted. d. Compressor coil Coil shorted. e. Circuit Parts Poor contacting or shorted. Replace each component. Check a starting voltage. Low voltage. Raise the voltage. Check if current flows to starting devices.
6-4 SERVICE DIAGNOSIS CHART COMPLAINT POINTS TO BE CHECKED Cooling is impossible. • Is the power cord unplugged from the outlet? • Check if the power S/W is set to OFF. • Check if the fuse of power S/W is shorted. • Measure the voltage of power outlet. • Plug to the outlet. • Set the switch to ON. • Replace a regular fuse. • If voltage is low, wire newly. Cooling ability is poor. • Check if the set is placed close to wall. • Check if the set is placed close to stove, gas • cooker and direct rays.
6-5 REFRIGERATING CYCLE ▼ Troubleshooting Chart STATE OF THE SET CAUSE STATE OF THE EVAPORATOR TEMPERATURE OF THE COMPRESSOR REMARKS LEAKAGE CLOGGED BY DUST PARTIAL LEAKAGE Freezer and Refrigerator don't get cold normally. Low flowing sound of Refrigerant is heard and frost forms in inlet only A little high more than ambient temperature. • A little Refrigerant • discharges. • Normal cooling is possible • when injecting Refrigerant • of regular amount.
▼ General Control of Refrigerating Cycle NO. ITEMS CONTENTS AND SPECIFICATIONS WELDING ROD (1) H 30 (1) • Chemical Ingredients (1) • Ag: 30%, Cu: 27%, Zn: 23%, Cd: 20% (1) • Brazing Temperature: 710~840°C (2) Bcup-2 (1) • Chemical Ingredients (1) • Cu: About 93% (1) • P: 6.8~7.5% (1) • The rest: within 0.
7. DESCRIPTION OF FUNCTION & CIRCUIT OF MICOM The following description is basically for GR-S552/GR-S592. For the other models, refer to the diagram of the entire PCB circuit. 7-1 FUNCTION 7-1-1 FUNCTION 1. When the appliance is plugged in, it is set to ‘Medium’. Each time the button is pushed, it is set to ‘Medium’→‘Medium/High’→‘High’→‘Low’→‘Medium/Low’→‘Medium’ in order. 2. When the power is initially applied or restored after a power failure, it is automatically set to ‘Medium’.
7-1-4 DEFROSTING 1. The defrosting is performed each time when the total running time of the compressor reaches 7 hours. 2. After the power is turned on (or restored after a power failure), the defrosting starts when the total running time of the compressor reaches 4 hours. 3. When the temperature of the defrosting sensor reaches 10 °C or above, the defrosting stops. If the temperature does not reach 10 °C in 2 hours after the defrosting starts, the defrosting error code is displayed.
7-1-6 ERROR DIAGNOSTIC MODE 1. The error diagnostic mode allows the SVC when a fault that may affect the performance of the product occurs while operating the product. 2. Even if the function control button is pushed when an error occurs, the function will not be performed. 3. When the error is cleared while the error code is displayed due to a fault, the appliance returns to the normal condition (Reset). 4.
7-2 PCB FUNCTION 7-2-1 POWER CIRCUIT The secondary part of the TRANS is composed of the power supply for the display and relay drive (12Vdc) and that for the MICOM and IC (5Vdc). The voltage for each part is as follows. PART VA 1 CE 2 CE3 VOLTAGE 220 Vac 12 Vdc 5 Vdc VA1 is a part for preventing the over voltage and noise.
7-2-2 OSCILLATION CIRCUIT This circuit is to generate 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 the authentic parts since the calculating time by the IC1 may be changed or it will not work if the OSC1 SPEC is changed.
7-2-4 LOAD DRIVE CIRCUIT 1. Load Drive Condition Check Freezer Fan Motor Double Cooling Load Type Comp Defrosting Heater High RPM Standard RPM Fan Motor (R-Fan) Measurement Location (IC5) No. 16 No. 13 No. 15 No. 14 No.
7-2-5 TEMPERATURE SENSOR CIRCUIT The upper CIRCUIT reads REFRIGERATOR temperature and DEF-SENSOR temperature for defrosting into MICOM. OPENING or SHORT state of each TEMPERATURE SENSOR are as follows. SENSOR CHECK POINT Refrigerator Sensor POINT A Voltage Defrosting Sensor POINT B Voltage NORMAL(-30 °C ~ 50 °C) SHORT-CIRCUITED OPEN 0.5 V ~ 4.5 V 0V 5V 7-2-6 DOOR OPEN DETECTION CIRCUIT Measurement Location (Pin No.
7-2-7 TEMPERATURE COMPENSATION & OVERCOOLING/UNDERCOOLING COMPENSATION CIRCUIT 1. Refrigerator Temperature Compensation Refrigerator Resistance Temperature (RCR1) Compensation 180 KΩ +2.5 °C 56 KΩ +2.0 °C 33 KΩ +1.5 °C 18 KΩ +1.0 °C 12 KΩ +0.5 °C 10 KΩ 0 °C Standard Temperature 8.2 KΩ -0.5 °C Compensation by lowering the temperature 5.6 KΩ -1.0 °C 3.3 KΩ -1.5 °C 2 KΩ -2.0 °C 470 Ω -2.
7-2-8 KEY BUTTON INPUT & DISPLAY LIGHT ON CIRCUIT ➧ The circuit shown above is to determine whether a function control key on the operation display is pushed and to turn on the corresponding function indication LED. The drive type is the scan type.
7-3 RESISTANCE SPECIFICATION OF SENSOR TEMPERATURE SENSOR RESISTANCE OF REFRIGERATOR (DEFROST) SENSOR - 20 ˚C 77 KΩ - 15 ˚C 60 KΩ - 10 ˚C 47.3 KΩ - 5 ˚C 38.4 KΩ 0 ˚C 30 KΩ + 5 ˚C 24.1 KΩ + 10 ˚C 19.5 KΩ + 15 ˚C 15.9 KΩ + 20 ˚C 13 KΩ + 25 ˚C 11 KΩ + 30 ˚C 8.9 KΩ + 40 ˚C 6.2 KΩ + 50 ˚C 4.3 KΩ • The resistance of SENSOR has ±5% common difference. • Measure the resistance of SENSOR after leaving it over 3 minutes in measuring temperature.
7-4 TROUBLE SHOOTING CLASSIFICATION 1. All the DISPLAY LED OFF 2. DISPLAY LED represents abnormal operation. STATE OF TROUBLE 1. COMPRESSOR operates? 1. FREEZER/ REFRIGERATOR 2. LAMP is dim. 3. The connection of CONNECTOR of MAIN PWB. POINT BE CHECKED Check the MAIN PCB. FREEZER/REFRIGERATOR DOOR OPEN CHECK with the naked. Certify connection of CONNECTOR. CHECKING METHOD • Replace PCB when no trouble after checking the contents of trouble. POWER SOURCE is poor NO COOLING 2.
CLASSIFICATION REFRIGERATOR STATE OF TROUBLE NO DEFROSTING. poor. TEMPERATURE is COOLING is poor. DEFROSTING is poor. POINT BE CHECKED 1. FREEZER TEMPERATURE is normal? 2. Cool air of FAN MOTOR is is sufficient? CONTENT REMEDY Certify the attaching state CHECKING METHOD See "FREEZER Replace FAN MOTOR. of DOOR. FAN MOTOR is poor. Remove impurities. TEMPERATURE is poor". Certify the amount of cool air Passage of cool air blocking. Replace HEATER.
7-5 MAIN PWB ASS'Y AND PARTS LIST 7-5-1 MAIN PWB ASS'Y 1.
7-5-2 REPLACEMENT PARTS LIST - 29 -
7-5-3 PWB ASS'Y, DISPLAY AND PARTS LIST - 30 -
7-6 PWB DIAGRAM - 31 -
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8. EXPLODED VIEW ▼ The parts of refrigerator and the shape of each part are subject to change in different localities.
*: optional parts 405C 200A 404A 330B 405C 405A 203A 205A 201A 329A 332A * 205A 212G 212A 212C * * * 125A 149A 125H * * * * 131C 149A * * 131A 210B 131A 136A 210A * 136B 125A * * * * 230A 125A 235A 149B 233A 234B 149B 233B 231A 136N * * * 140A * * 136P 149C 149C or 241A 205A 244A 136Q * 136R 244C 241C 154A or 205A 241A 151A 241D 155K 243A 243B 151A - 34 -
