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KIMCHI REFRIGERATOR SERVICE MANUAL CAUTION PLEASE READ CAREFULLY THE SAFETY PRECAUTIONS OF THIS MANUAL BEFORE CHECKING OR OPERATING THE REFRIGERATOR. MODEL : GR-K24PS/GR-K243UG...
Safety regulations 1. First check if there is any electric leakage in the refrigerator unit. 2. Always unplug the refrigerator before handling any electricity conducting parts. 3. When testing the refrigerator with the power on, use insulated gloves for safety. 4.
Safety warnings and cautions Chapter 1. Safety warnings and cautions u Always observe the 'Safety Warnings' and 'Cautions', which hare intended to ensure safety while repairing or operating the product. u Precautions are classified into 'Warning' and 'Caution', as explained below. w Warning Warning means a dangerous condition which could result in significant damage, injury or death if the instructions are not followed.
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Safety warnings and cautions w Warning This product should always be Do not store flammable liquid or gas in grounded, when needed. the refrigerator such as ether, benzene, alcohol, medicine, LP gas etc. If you think that there is a possibility of electricity leakage by water or moisture, always ground the unit.
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Safety warnings and cautions w Caution When using the refrigerator for low Always use exact replacement parts. temperature in freezer or refrigerator, Make sure that the model name, voltage, current and do not store bottles. temperature ratings are correct for the electric part. Bottles can freeze and cause the bottles to crack, which can cause an injury.
3-1. Method to adjust height of refrigerator First adjust the level of the refrigerator. (If the floor is uneven, the refrigerator may vibrate or cause noise.) GR-K24PS Horizontal adjustment leg (lower handle part) u Adjust the front to be leveled by turning the height adjustment screws under the front corners in the arrow direction.
MICOM function and circuit description Chapter 5. MICOM function and circuit description 5-1. Function description 5-1-1. Display part 1) GR-K24PS 2) GR-K243UG Cabbage/Radish/Mul Kimchi Vegetable/Fruit Light freezing Freezing food Rice Chungukjang NOTCH Mid Max Temperature 0°C -1.0°C -2.0°C 3.5°C 2.5°C 1.5°C -4.0°C -5.0°C -6.0°C...
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MICOM function and circuit description 5-1-2. Food storage/seasoning function (1) When selecting food type and storing temperature 1. Press the “Lock/Unlock” button for more than 2 seconds to switch to “Unlock” status. 2. Press the “Compartment selection” button to select the compartment to use. 3.
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MICOM function and circuit description 5-1-3. When selecting power on/off function 1. Press the “Lock/Unlock” button for more than 2 seconds to switch to “Unlock” status. 2. Press the “Compartment selection” button to select the compartment. 3. At this time, press the “Power” button for more than 2 seconds to turn the power off. 4.
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MICOM function and circuit description 5-1-5. Temperature control method 1. The compressor runs or stops and the 3-way valve opens or closes depending on the temperature sensed by each sensor. 2. If the temperature in either compartment is unsatisfactory, the compressor is turned on and the 3-way value is opened to the affected compartment.
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MICOM function and circuit description 5-1-9. Sequential operation of components Components (compressor, 3-way valve, lid left compartment seasoning heater, lid right compartment seasoning heater, drawer left compartment heater and drawer right compartment heater) are operated in a specific order to prevent damage and noise caused by simultaneous operation of all parts when the unit is started and after completing the self-test routine.
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3. If an error occurs and is resolved, the refrigerator will default to the normal status. (The unit is reset.) 4. The error codes are shown in segment for the remaining seasoning time display of the right compartment, and all LEDs, except for failure code, are turned off. 1) GR-K24PS 2) GR-K243UG Item...
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MICOM function and circuit description 5-1-11. Test function 1. The test function checks the functions of the PCB and the refrigerator, searching for errors in parts. 2. The test switch on the PCB operates the test mode. The refrigerator reverts to the normal mode after 2 hours if you forget to end it manually.
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MICOM function and circuit description 5-2. Circuit description 5-2-1. Power circuit The power circuit consists of the noise attenuation part and the SMPS (Switch Mode Power Supply) part. The SMPS consists of the rectifier (BD1 & CE1) to convert AC voltage to DC voltage, switching part (IC3) to switch the converted DC voltage, transformer to transmit energy of the first side of the switching end to the second side, the secondary power to supply power to MICOM and IC, and the feedback part (IC4) to feedback the secondary voltage to the first side of the transformer in order to maintain the secondary voltage constant.
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MICOM function and circuit description 5-2-4. Load/Buzzer driving circuit (1) Load driving circuit Lid left compartment Lid right compartment Drawer left compartment Drawer right Drawer l e ft compartment COMP. fan motor Type of load seasoning heater seasoning heater seasoning heater compartment rice heater Chungukj a ng heater Measuring point(IC7)
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MICOM function and circuit description 5-2-5. Switch input circuit The following circuit is the input circuit to detect the test switch signal to check the refrigerator. RAR2 5-2-6. Temperature sensor circuit The following temperature sensor circuit consists of a sensor to detect the outside (ambient) temperature, sensors in the lid left and right compartment, sensor in the drawer left and right compartment for storing and seasoning Kimchi.
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MICOM function and circuit description 5-2-7. Stepping motor operation circuit (3-way valve) u The motor is operated by sending out “High” and “Low” signals as many as the designated number of steps through MICOM Pin 44, 43, 46, 45 (lid part) and 48, 47, 50, 49 (drawer part) to rotate the motor through the magnetic field formed by the motor and the coil wrapped around each stator.
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MICOM function and circuit description 5-2-9. Storing temperature compensation and over-cool/under-cool cut compensation circuit (1) Storing temperature compensation u This is the circuit to input the temperature compensation level required for adjusting storage temperature at the left or right compartment of the lid or drawer. Lid left compartment Lid right compartment Drawer left compartment Drawer right compartment Temperature...
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MICOM function and circuit description (2) Over-cool/Under-cool cut compensation Drawer left compartment storing Li d l e ft compartment cut Li d ri g ht compartment cut Drawer l e ft compartment cut Lid left Lid right Drawer left Drawer right temperature compensation compensati o n compensati o n...
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MICOM function and circuit description 5-2-10. Communication circuit between main PCB and display PCB This circuit provides communications between the MICOM on the main PCB and the MICOM of the display PCB. If there is no communication between these boards for 30 seconds, a communication error occurs. MICOM for LED/LCD control Send (Error status)
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MICOM function and circuit description 5-2-11. Button input and display part illumination circuit This circuit determines which buttons are pressed and drives the LED display, whose driving method is a scan method. P P R R E E M M I I U U M M / / S S T T A A N N D D A A R R D D / / F F I I G G H H T T I I N N G G ( ( L L E E D D M M O O D D U U L L E E T T Y Y P P E E ) ) D110 IN4004X6 D111...
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MICOM function and circuit description P P R R E E M M I I U U M M M M O O D D E E R R N N C C O O L L O O R R ( ( L L E E D D M M O O D D U U L L E E T T Y Y P P E E ) ) , - 24 -...
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MICOM function and circuit description 5-3. Sensor resistance characteristics table Lid left compartment, lid right compartment, drawer left Measuring temperature (°C) compartment, drawer right compartment, outside sensor -20°C 77 KΩ -15°C 60 KΩ -10°C 47.3 KΩ -5°C 38.4 KΩ 0°C 30 KΩ...
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MICOM function and circuit description 5-4. PCB parts diagram and parts list 5-4-1. PWB (PCB) assembly and main parts diagram - 26 -...
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MICOM function and circuit description 5-4-2. PWB (PCB) assembly and main parts list g The parts list can slightly change according to the situation. YW396-10AV(10P-1,2,4,6,8,10)BLUE YW396-09AV(9P-1,3,5,8)YELLOW DH12D1-O-Q GBL06 - 27 -...
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MICOM function and circuit description - 28 -...
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MICOM function and circuit description 5-4-3. PWB (PCB) assembly and display parts diagram and parts list (6871JB1395_) g The parts diagram and parts list can slightly change according to the situation. - 29 -...
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MICOM function and circuit description - 30 -...
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MICOM function and circuit description 5-4-3. PWB (PCB) assembly, sub parts diagram and parts list (common for 6871JB2073A/B left and right) g The parts diagram and parts list can slightly change according to the situation. - 31 -...
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MICOM function and circuit description 5-5. PCB circuit diagram 5-5-1. PWB (PCB) assembly and main circuit diagram (6871JB1246) g PCB circuit diagram can slightly change according to the situation. - 32 -...
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MICOM function and circuit description PWB(PCB) ASSEMBLY, DISPLAY :6871JB1395, 6871JB1463 Module - 33 -...
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MICOM function and circuit description 5-5-2. PWB (PCB) assembly and display circuit diagram (6871JB1395_) g The circuit diagram can slightly change according to the situation. g This includes the PWB (PCB) assembly and sub circuit diagram. D110 IN4004X6 D111 D112 D113 D114 D115...
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MICOM function and circuit description - 35 -...
Freezing cycle and refrigerant Chapter 6. Freezing cycle and refrigerant 6-1. Freezing cycle (Freezing principle/Refrigerant gas circulation diagram) 6-1-1. Freezing principle Freezing is an operation of maintaining a lower temperature (generally 0°…) than the natural temperature (usually ambient temperature surrounding us). This requires an insulated space, refrigerant (R134a) to absorb the heat and the circulation circuit (compressor, condenser, evaporator etc.) to operate the phase change of the refrigerant.
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Freezing cycle and refrigerant 6-1-3. Operation description of each circulation circuit Parts name Operation details Refrigerant gas condition (input and output) Compressor Compress the refrigerant from low pressure Low pressure gas¡ High pressure gas to high pressure. Temperature(30°C)¡ (80~120°C) Condenser High pressure gas refrigerant exhausts heat High pressure gas¡...
General details about the product Chapter 7. General details about the product 7-1. Refrigerator noise The structure of the freezing room and mechanical room, which are the sources of Kimchi refrigerator noise, is as follows. Here you can see that the main source of noise during refrigerator operation is the compressor, the condenser and the fan motor that cools the compressor in the mechanical room.
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General details about the product (2) Service method for major noise claim item for Kimchi refrigerator Noise claim Noise generation Service method Remarks Noise from poor • Reinforce the floor hardness u The installation floor surface is installation • Move the installation location not hard enough •...
Characteristics of each part 8-1. Refrigerant valve (1) Function This switches the refrigerant that went through the compressor to the lid left/right or drawer left/right evaporator. g When connecting the 3-way valve and capillary tube, they must be welded by matching the same color as shown below. If not matched, it can cause a problem to the refrigerator.
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Characteristics of each part (3) Operating principle Controlling the rotating angle of the stepping motor will open/close the outlet pipe entrance by changing the shape of the valve connected to the bottom of the rotor. Left/Right compartment open Right compartment open Left/Right compartment open Left compartment open (STEP : 54)
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Characteristics of each part 8-2. Motor (mechanical room) (1) Function • Motor cooling (mechanical room) This is the part used for circulating the air within the mechanical room and applies to the wire condenser type. This operates when the compressor operates and the heated refrigerant from the compressor lowers the temperature when passing through the wire condenser and also reduces the temperature of the compressor to improve the performance.
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Characteristics of each part • Operating principle When the AD power is connected to the coil of the shading pole motor, the central axis of the magnetic field shifts in the bold arrow direction of <Fig. 2>. As the central axis moves, the rotor Current moves in the same direction to turn the motor.
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Characteristics of each part 8-3 Heater (1) Introduction When using the refrigerator, several heaters are applied to season the Kimchi or store the rice. (2) Heater type and role Classification Applied part Function Resistance value Remarks 80W × 2EA Heater assembly External surface of inner case For Kimchi seasoning 165Ω/EA...
• If the lead wire coating is disconnected or the coating is damaged, it can cause a short circuit. 2. Frame assembly, display GR-K24PS • Using the - driver, open the slot between the frame display and the case-U to disassemble the unit. At this...