KRSVM000070923 b1

http://biz.lgservice.com REFRIGERATOR SERVICE MANUAL CAUTION BEFORE SERVICING THE UNIT, READ THE "SAFETY PRECAUTIONS" IN THIS MANUAL Ref No GR-642QUP MODEL: GR-648QUP COLOR: SILKY GREY CONTENTS CONTENTS SERVICING PRECAUTIONS SPECIFICATIONS PARTS IDENTIFICATION DISASSEMBLY 6-7 DOOR DOOR SWITCH FAN AND FAN MOTOR DEF' CONTROL ASM LAMP CONTROL BOX-R ADJUSTMENT 8-9 COMPRESSOR PTC-STARTER OLP (OVER LOAD PROTECTOR) CIRCUIT DIAGRAM TROUBLESHOOTING 10-17 COMPRESSOR AND ELECTRIC COMPONENTS 12 PTC AND OLP 13 ANOTHER ELECTRIC COMPONENT 14 SERVICE DIAGNOSIS CHART 15 REFRIGERATING CYCLE 16-17 DESCRIPTION OF FUNCTION & CIRCUIT OF MICOM 18-38 EXPLODED VIEW & REPLACEMENT PARTS LIST 39- SAFETY PRECAUTIONS Please read the followings before servicing your refrigerator When you stand up during observing the lower part with the upper door open, move with care to prevent head wound which may happen by hitting the upper door Check if an electric leakage occurs in the set To prevent electric shock, unplug prior to servicing In case of testing with power on, wear rubber gloves to prevent electric shock When sloping the set, remove any materials on the set, especially thin plate type (ex.: glass shelf or books.) If you use any appliances, check regular current, voltage and capacity When servicing evaporator part, wear cotton gloves without fail It is to prevent wound by sharp fin of evaporator Don't touch metal products in cold freezer with wet hand It may cause frostbite Prevent water flowing to electric elements in mechanical parts 10 Leave a breakage of refrigerating cycle to a heavy service center The gas in cycle inside may soil ambient air -2- 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 If the defects have been found, empty the old system of eventual R-134a residue by breaking off the end of the extension piece at its narrow point (Figure 1) Replace the filter and any damaged components Unsolder and pull off the piece remaining inside the service tube and then attach an extension completely with male Hansen and last, solder it to the same tube again (Figure 2) POINT TO BE BROKEN TO THE R-134a CYLINDER CHARGE TUBE EXTENSION FEMALE HANSEN TO THE REFRIGERATION SYSTEM MALE HANSEN SERVICE TUBE EXTENSION Figure SOLDERING POINT Figure Figure Before performing this operation (if the vacuum pump and refilling cylinder are connected), make sure that the valve placed between the vacuum pump and refilling tube are closed to keep the Freon for adding to the system (Figure 5) It is necessary to execute the soldering operation with valve open so that the fumes caused by oil residue can come out freely without blowholes between two tubes during heating the point to be soldered The extension fitted with the male Hansen is connected to the female fitting of the vacuum pump tube (Figure 3) FILLING OR CHARGE TUBE VALVE TO BE OPENED WHEN REFILLING TO THE REFRIGERATION SYSTEM TO THE CHARGE CYLINDER VALVE TO BE CLOSED AFTER VACUUM TO THE VACUUM PUMP TO THE VACUUM PUMP PRESSURE GAUGE Figure In addition, check the graduated scale on the cylinder for the quantity of R-134a to be added, for example, if we have 750 grams of Freon in the cylinder and must add 165 grams to the group, this amount will be reached when R-134a has dropped to 585 grams, remembering that the indicator shows a lower limit of meniscus Do this after choosing the scale corresponding to the gas pressure different scales reported as the same gas pressure indicated by the pressure gauge on the top of the column To make R-134a flow into the system, open the valve placed at the base of the cylinder and connected to the filling tube The amount of Freon cannot be added to the system all at once because it may cause a blocking of motor-compressor Therefore, proceed by adding original quantity of about 20-30 grams and close the valve immediately The pressure rises and the motor-compressor must start, sucking the gas and making the pressure go down again Regulate the valve again, maintaining the same manner until reaching to the quantity of R-134a established for the system being charged When the system is running, the suction pressure must be stabilized between 0.10 to 0.4 atmosphere Figure Air evacuating from the system begins so soon as the pump starts The refrigeration system must be kept under vacuum until the reading on the low-pressure gauge indicates vacuum (0 absolute, -1 atm., -760 mm hg) in any case it is advisable to keep the pump running for about 60 minutes (Figure 3) In case that a considerable leakage occurs and to stop the vacuum pump will be necessary and add a small quantity of Freon to the system, if vacuum should not be obtained (pressure gauge can't fall to atmosphere), start the refrigeration unit and find the leakage with the special leakfinder When the defective soldering point is visible, re-do it after opening the extension tube valve and reestablishing the normal outside pressure inside the group Because the melted alloy is sucked into the tubes and block them, the pressure must be rebalanced when vacuum is in the system in soldering As soon as the -3- SPECIFICATIONS 1-1 GR-S642P ITEMS FREEZER SPECIFICATIONS ITEMS 146 SPECIFICATIONS FREEZER EA REFRIGERATOR EA SHELF NET CAPACITY REFRIGERATOR (l) TOTAL 379 525 VEGETABLE TRAY Drawer Type DIMENSIONS (mm) 860(W)X709(D)X1794(H) EGG TRAY Pieces NET WEIGHT (kg) 95 ICE TRAY Pieces (Plastic) COOLING SYSTEM Fan Cooling ICE BANK Piece TEMPERATURE CONTROL Micom Control COMPRESSOR P.T.C Starting Type Full Automatic EVAPORATOR Fin Tube Type Heater Defrost CONDENSER Wire Condenser OUT CASE Pre Coated Metal REFRIGERANT R-134a (140g) INNER CASE ABS DEFROSTING DEVICE HEATER INSULATION Cyclo-Pentane Foam DEFROSTING SYSTEM 1-2 GR-S702P ITEMS FREEZER SPECIFICATIONS ITEMS 154 SPECIFICATIONS FREEZER EA REFRIGERATOR EA SHELF NET CAPACITY REFRIGERATOR (l) TOTAL 399 553 VEGETABLE TRAY Drawer Type DIMENSIONS (mm) 860(W)X729(D)X1794(H) EGG TRAY Pieces NET WEIGHT (kg) 97 ICE TRAY Pieces (Plastic) COOLING SYSTEM Fan Cooling ICE BANK Piece TEMPERATURE CONTROL Micom Control COMPRESSOR P.T.C Starting Type Full Automatic EVAPORATOR Fin Tube Type Heater Defrost CONDENSER Wire Condenser OUT CASE Pre Coated Metal REFRIGERANT R-134a (140g) INNER CASE ABS DEFROSTING DEVICE HEATER INSULATION Cyclo-Pentane Foam DEFROSTING SYSTEM -4- 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 Water Dispenser Deodorizer Utility Corner 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 -5- ● Putting The Water In The Water Tank Turn the lock dial in the direction of the arrow as shown to remove it and pour water into the dispenser water tank 2-2 WATER DISPENSER ● Features DISPENSER PAD Close the cap by tilting it and putting one side in first and then the other side as shown GRILLE DRIP TRAY TAB HOLE Place the water tank in the tank holder inside the refrigerator Make sure that the groove on the connecting part is in position with the tab Push the connecting part into the hole until it "Clicks" MOTOR (INSIDE) HOLDER RING Fix the connecting part in place by means of the holder ring as shown BOTTLE HOLDER CONNECTING PART Tab Groove CAP CAUTION LOCK DIAL Do not use anything other than water including soft drinks, milk and juices Hot water needs to be cooled before being put in the water tank Always use the holder ring to fix the water tank in place to prevent the tank from moving or getting loose HANDLE WATER TANK WATER TANK ● Drinking Press the dispenser pad with the glass The water is released when the dispenser pad is pressed The pad returns to its original position when the glass is removed, and the water stops its flow NOTE The lamp is lit when the dispenser pad is pressed and the water is released This makes it possible to see the water level in the dark The motor rotates in reverse for a few seconds after the dispenser is released to dispose of any water remaining in the tubes (This may cause the sound of water being sucked back inside) -6- ● Cleaning Water Tank Remove the cap Grille and Drip Tray Pull the drip tray out and remove with the grille Dispose of the water in the kitchen sink, wash the drip tray and the grille with a mild detergent and rinse thoroughly Clean the inside and outside of the water tank with dishwashing detergent and rinset horoughly under running water Other Parts Remove the cap and, clean the cap and connecting part with a mild detergent and rinse thoroughly CAUTION Use lukewarm water when cleaning Do not use anything other than water If it is used with soft drinks, put water in the water tank and discharge three or four cups of water shortly -7- DISASSEMBLY 3-1 DOOR 3-2 DOOR SWITCH ● Freezer To remove the door switch, pull out it with a '—' type driver as shown in (figure 9) Disconnect the lead wire from the switch Door Remove the hinge cover by pulling it upwards Loosen hexagonal bolts fixing the upper hinge to the body and lift the freezer door HINGE COVER BOLT HINGE Figure Figure 3.3 FAN AND FAN MOTOR Pull out the door gasket to remove from the door foam Ass'y Remove the freezer shelf Remove the Cover Lamp-F and Case Lamp by loosening screw fixed to ceiling of Inner Case GASKET Figure 11 Figure Remove the Grille by pulling it out Pull out the Shroud and remove the Fan Motor Assy by loosening screws Pull out the fan and, separate the Fan Motor, Brackets and the Guide Fan Refrigerator Door Loosen hexagonal bolts fixing the lower hinge to the body to remove the refrigerator door only ● SHROUD FAN MOTOR LOWER HINGE BOLT GUIDE FAN FAN GRILLE Figure Figure 12 Pull out the door gasket to remove from the door foam Ass'y -8- 3-5-1 Freezer room lamp Unplug the power cord from the outlet 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) Remove the lamp by turning it counterclockwise 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 Defrost Sensor functions to defrost automatically and it is attached to the Evaporator and the metal side of the case senses Temp Fuse-M is a kind of safety device for preventing overheating of the Heater when defrosting At the temperature of 72°C, it stops the emission of TEMP from the Defrost Heater Pull out the shroud-F after removing the Grille Fan (Figure 13) Separate the connectors connected with the Def Control ASM and replace the Def Control ASM after cutting the Tie Wrap (Figure 14) SHROUD-F FAN 3-5-2 Refrigerator room lamp Unplug the power cord from the outlet Remove refrigerator shelves Remove the room lamp lid by taking down while pulling forward with your hands as shown in (figure 17) Turn the lamp counterclockwise Assemble in reverse order of disassembly Replacement bulb must be the same specification as original DEF CONTROL ASM 3-6 CONTROL BOX-R First, remove all shelves in the refrigerator and Control Box-R by loosening screw Figure 13 Figure 14 MULTI FLOW DUCT 3-5 LAMP FREEZER ROOM LAMP REFRIGERATOR ROOM LAMP Figure 18 Figure 16 Loosen screws fixing the Control Box-R to the Inner Case after detaching the cap screw Remove the Control Box-R by pulling it downward Figure 17 -9- ADJUSTMENT 4-1 COMPRESSOR 4-1-1 Role 4-2-3 PTC-Applied Circuit Diagram ● According to Starting Method of Motor 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 OVERLOAD PROTECTOR C 4-1-2 Composition The Compressor is Composed of Compressor Apparatus compressing gas, Compressor Motor moving Compressor Apparatus and Case protecting Compressor Apparatus and Motor There are PTC-Starter, and Over Load Protector (OLP) in the Compressor outside On the other hand, because the Compressor consists of 1/1000mm processing precision components and is sealed after producing without dust or humidity, deal and repair with care 4-1-3 Note to Use (1) Be careful not to allow over-voltage and over-current (2) No Strike If applying forcible power or strike (dropping or careless dealing), poor operation and noise may occur (3) Use proper electric components appropriate to the Compressor (4) Note to Keep Compressor If Compressor gets wet in the rain and rust in the pin of Hermetic Terminal, poor operation and poor contact may cause (5) Be careful that dust, humidity, and flux due to welding don't inflow in Compressor inside in replacing Compressor Dust, humidity, and flux due to welding which inflows to Cylinder may cause lock and noise 4-2 PTC-STARTER 4-2-1 Composition of PTC-Starter (1) PTC (Positive Temperature Coefficient) is no-contact semiconductor starting device which uses ceramic material and the material consists of BaTiO3 (2) The higher the temperature is, the higher resistance value becomes These features are used as starting device of Motor 4-2-2 Role of PTC-Starter (1) PTC is attached to Hermetic Compressor used for Refrigerator, Show Case and starts Motor (2) Compressor for household refrigerator applies singlephase induction Motor For normal operation of single-phase induction motor, in the starting operation flows in both main coil and subcoil After the starting is over, the current is cut off in subcoil The proper features of PTC play the above all roles So, PTC is used as a starting device of motor PTC S PTC STARTER COMPRESSOR MOTOR M M S HERMETIC TERMINAL RSIR Figure 20 4-2-4 Motor Restarting and PTC Cooling (1) For restarting after power off during normal Compressor Motor operation, plug the power cord after for pressure balance of Refrigerating Cycle and PTC cooling (2) During normal operation of Compressor Motor, PTC elements generate heat continuously Therefore, if PTC isn't cooled for a while after power off, Motor can't operate again 4-2-5 Relation of PTC-Starter and OLP (1) If power off during operation of Compressor and power on before PTC is cooled, (instant shut-off within or reconnect a power plug due to misconnecting), PTC isn't cooled and a resistance value grows As a result, current can't flow to the sub-coil and Motor can't operate and OLP operates by flowing over current in only main-coil (2) While the OLP repeats on and off operation about 3-5 times, PTC is cooled and Compressor Motor performs normal operation If OLP doesn't operate when PTC is not cooled, Compressor Motor is worn away and causes circuitshort and fire Therefore, use a proper fixed OLP without fail 4-2-6 Note to Use PTC-Starter (1) Be careful not to allow over-voltage and over-current (2) No Strike Don't apply a forcible power or strike (3) Keep apart from any liquid If liquid such as oil or water inflows into PTC, PTC materials it may break due to insulation breakdown of material itself (4) Don't change PTC at your convenience Don't disassemble PTC and mold If damaging to outside of PTC-starter, resistance value alters and poor starting of compressor motor may cause (5) Use a properly fixed PTC - 10 - 7-2-6 SWITCH INPUT CIRCUIT * The circuit shown below is the input circuit to detect the signals of the test S/W for checking the refrigerator 7-2-7 TEMPERATURE COMPENSATION & OVERCOOLING/UNDERCOOLING COMPENSATION CIRCUIT The circuits for less cooling and overcooling compensation in a refrigerator compartment CUT OVER COOLING COMPENSATION JCR1 JCR2 LESS COOLING COMPENSATION JCR3 JCR4 CUT CUT +1°C CUT +2°C CUT CUT CUT CUT CUT REFRIGERATOR TEMPERATURE COMPENSATION VALUES CUT -2°C CUT 0°C CUT 0°C CUT CUT -1°C CUT CUT CUT +1°C -1°C 0°C(AT FACTORY) • The above OPTION circuit is to compensate refrigerator temperature by simply cutting during service - 28 - REMARKS 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 (LED Module) The drive type is the scan type - 29 - 7-2-9 DISPENSER PUMP MOTOR OPERATION CIRCUIT(OPTION) Press the DISPENSER PUMP S/W, the MOTOR turns a forward rotate and release the S/W the MOTOR is stop for 0.6 second and turns a reverse rotate for 0.5 second MOTOR OPERATION STATE CHECK POINT PUMP S/W OPERATION STOP A FORWARD ROTATE STOP A REVERSE ROTATE 0.6 sec 0.5 sec STOP RELEASE PRESS PUMP MOTOR OPERATION A FORWARD ROTATE STOP A REVERSE ROTATE PUMP S/W PART PUMP MOTOR PART both ends of CC11 H L H H H NO 11 of IC1 H H H L H NO 12 of IC1 H L H H H VOLTAGE CHECK as MULTIMETER (connect +, –) 0V 12V 0V -12V 0V - 30 - 7-3 RESISTANCE SPECIFICATION OF SENSOR TEMPERATURE SENSOR RESISTANCE OF FREEZER SENSOR RESISTANCE OF REFRIGERATOR (DEFROST) SENSOR - 20 ˚C 22.3 KΩ 77 KΩ - 15 ˚C 16.9 KΩ 60 KΩ - 10 ˚C 13.0 KΩ 47.3 KΩ - ˚C 10.1 KΩ 38.4 KΩ ˚C 7.8 KΩ 30 KΩ + ˚C 6.2 KΩ 24.1 KΩ + 10 ˚C 4.9 KΩ 19.5 KΩ + 15 ˚C 3.9 KΩ 15.9 KΩ + 20 ˚C 3.1 KΩ 13 KΩ + 25 ˚C 2.5 KΩ 11 KΩ + 30 ˚C 2.0 KΩ 8.9 KΩ + 40 ˚C 1.4 KΩ 6.2 KΩ + 50 ˚C 0.8 KΩ 4.3 KΩ • The resistance of SENSOR has ±5% common difference • Measure the resistance of SENSOR after leaving it over minutes in measuring temperature This postponing is necessary because of perceiving speed • Measure the F-SENSOR, SUPER FROST SENSOR, R1, R2-SENSOR after disconnect CON5 of PWB ASSY, MAIN - 31 - 7-4 TRUBLE SHOOTING POWER SOURCE is poor CLASSIFICATION NO COOLING All the DISPLAY LED OFF DISPLAY LED represents abnormal operation STATE OF TROUBLE COMPRESSOR operates? FREEZER/ REFRIGERATOR LAMP is dim The connection of CONNECTOR of MAIN PWB POINT BE CHECKED 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 COOLING is poor Whether refrigerant leaks or leaks or not Whether FAN MOTOR operates or not Measure the amount of frost sticking on EVA and the surface temperature of condenser pipe PRESS TEST KEY on MAIN PWB once (forced COOLING) PRESS TEST KEY on MAIN PWB once (forced COOLING) •If pass less than minutes after stop of COMP, don't press it and stand-by FREEZER TEMPERATURE is poor DEFROSTING normal? SENSOR normal? Certify the amount of frost sticking on EVA Check resistance the SENSOR in the Refrigerator CONTENT POWER SOURCE is poor Applied voltage mistake CONNECTOR connection is poor TRANS FUSE open REMEDY Certify Fuse Certify outlet Voltage Use boosting TRANS Reconnect CONNECTOR Replace TRANS Replace COMPRESSOR Replace OLP, PTC Replace MAIN PWB RY1 Certify the black wire of MAIN PWB CONNECTOR (CON2) Remedy the leaking part and reaching Refrigerant FAN MOTOR is poor DOOR LINE contact CONETTING WIRE is poor Replace FAN MOTOR Replace DOOR LINER Certify MOTOR and the connection of the black wire of MAIN PWB CONNECTOR (CON2) COMPRESSOR lock or blocked OLP, PTC is poor COMPRESSOR RELAY is poor THE CONNECTING WIRE is poor Refrigerant leakage DEFROSTING is poor See the DEFROSTING trouble Replace SENSOR SENSOR RESISTANCE is poor - 32 - CLASSIFICATION REFRIGERATOR STATE OF TROUBLE NO DEFROSTING poor TEMPERATURE is COOLING is poor DEFROSTING is poor POINT BE CHECKED FREEZER TEMPERATURE is normal? Cool air of FAN MOTOR is is sufficient? CONTENT REMEDY Certify the attaching state CHECKING METHOD See "FREEZER Replace FAN MOTOR FAN MOTOR is poor of DOOR Certify the amount of cool air Remove impurities TEMPERATURE is poor" Passage of cool air blocking Replace HEATER and its speed touching check supplied into HEATER disconnection See "DEFROSTING is poor" TEMPERATURE FUSE disconnection Connection is poor DEF-SENSOR is poor HEATER RELAY is poor DRAIN PIPE blocking Attaching is poor DOOR sticking is poor Reassemble DOOR Replace GASKET Replace TEMPERATURE FUSE Certify EVA connection and wire of MAIN PWB CONNECTOR Replace DEF-SENSOR Replace RY5 of MAIN PWB Remove ice and impurities Certify HEATER PLATE resistance Reassemble DEF-SENSOR EVA frozen REFRIGERATOR Certify DRAIN PIPE HEATER emit heat? DRAIN PIPE blocking? PRESS TEST KEY on MAIN on MAIN PWB three times (forced DEFROSTING) Remain ice at DEFROSTING? Certify the attaching of DEF-SENSOR Certify the attaching state(gap) of FREEZER/ REFRIGERATOR DOOR - 33 - 7-5 MAIN PWB ASS'Y AND PARTS LIST 7-5-1 MAIN PWB ASS'Y - 34 - 7-5-2 REPLACEMENT PARTS LIST - 35 - 7-5-3 PWB ASS'Y, DISPLAY AND PARTS LIST - 36 - 7-6 PWB DIAGRAM - 37 - - 38 - EXPLODED VIEW & REPLACEMENT PARTS LIST 8-1 ▼ The parts of refrigerator and the shape of each part are subject to change in different localities ▼ Capacitors and fuse are optional parts 501F 281A 103B 410G 301A 401A 281B 411A 501A 103A 501K 129A 418A 409A 158B 158A 406B 282B 304A 604E 105A 604G 317A 318A 283B 410J 314A 307A 308A 309A 310A 409C 409B 323B 312A 104A 420A 106A 106A 329C 158C 315B 319A 315A 328A 103C 329D 158F 319C 120A 315B 315C 324A - 39 - 405C 200A 405A 203A 201A 404A 205A 329A 330B 212G 332A 212A 205A 503B 212C 503C * * 149A 210B 131A 210A * 125A 230A 235A 233A * * * * 149A 125A 231A 131A 125H 241A 149B 244A 140A 244C 149C 241A 154A 241B 151A 241D 155B 243A 151A 243B - 40 - 611M 611A 611P 611N 611Q 611X 611T 611R 611C 611Y 611B 611D 611Z 611E 611H 611S 611W - 42 - 611K P/No 3828JD8415K AUG., 2002 Printed in Korea