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흥 정 판 Internal Use Only Website http://us.lgservice.com 30” Freestanding Electric Range SERVICE MANUAL MODEL: LRE30451SW / SB / ST CAUTION BEFORE SERVICING THE UNIT, READ THE SAFETY PRECAUTIONS IN THIS MANUAL. December, 2005 P/NO : 3828W5S6294 Printed in Korea...
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SAFETY PRECAUTIONS • Repairs of the appliance should be carried out by a licensed technician only. Incorrect repairs may result in dangerous situations. If you need repairs, contact an LG Service Center or your dealer. • If the power cord is defective, it must be replaced by a qualified service agent with a UL listed range cord.
GENERAL IMPOR ANT SAFETY INSTRUCTIONS IMPOR ANT SAFETY INSTRUCTIONS Read and follow all instructions before using your oven to prevent the risk of fire, electric shock, injury to person, or damage when using the range. This guide don’t cover all possible conditions that may occur. For further assistance contact your service agent or manufacturer.
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GENERAL IMPOR ANT SAFETY INSTRUCTIONS IMPOR ANT SAFETY INSTRUCTIONS SURFACE COOKING UNITS VENTILATING HOODS: • Clean Ventilating Hoods Frequently – Grease should not • Use Proper Pan Size – This appliance is equipped with one or be allowed to accumulate on hood or filter. more surface units of different sizes.
GENERAL MODEL & SERIAL NUMBER LABEL MODEL & SERIAL NUMBER LABEL AND TECH SHEET LOCA TIONS AND TECH SHEET LOCA TIONS The Model/Serial Number label and Tech Sheet locations are shown below. Model & Serial Number Location Tech Sheet Location (On Low Rear Cover)
GENERAL SPECIFICA TIONS SPECIFICA TIONS Model Number LRE30451SW / SB / ST Category Convection Overall Width 30" Installation type Freestanding Color availability WH, BK, STS Control Oven Keypad Cooktop Keypad Display Electronic clock & timer Control lock capability Audible preheat signal Special function 1.
USING YOUR RANGE GENERAL INFORMA TION GENERAL INFORMA TION Convection Bake / Roast Mode Rating Label Upper element, lower element, Rear element(some Model numbers are recorded on the rating label. model) and fan operate during convection bake. Rating label is located on the lower front left corner Convection bake should be used for cooking of the oven frame.
USING YOUR RANGE CONTROL P ANEL FEA TURES CONTROL P ANEL FEA TURES single single Left Rear element Warming zone Right Rear element Dual single Left Front element Right Front Dual element 1. BAKE PAD: Press to select the bake function. 12.
USING YOUR RANGE To turn on a single surface unit 4. TIMER ON/OFF (Right Rear, Left Rear, Right Front) TIMER Desired TIMER 1. Press ON/OFF pad for the desired element. ON/OFF time ON/OFF 2. Press ( ) pad to choose the desired setting. To cancel timer at any time, touch TIMER ON/OFF pad.
USING YOUR RANGE 10. THERMOSTAT ADJUSTMENT 13. CONVECTION BAKE The oven temperature can be adjusted from CONV. Desired START -35°F (-19°C) to 35°F (19°C). BAKE Temp. Note: The thermostat adjustments made with this feature will just change Bake, Convection Bake and Convection 14.
COMPONENT ACCESS This section instructs you on how to service each component inside the range. The components and their locations are shown below. COMPONENT LOCA TIONS COMPONENT LOCA TIONS Main PCB Cook Top Display PCB Door Locking Motor & Micro Switch Surface Elements Door Latch Assembly Door Switch...
COMPONENT ACCESS REMOVING THE BACK, CONTROL COVER REMOVING THE BACK, CONTROL COVER AND KEY MEMBRANE ASSEMBL AND KEY MEMBRANE ASSEMBL 4. Remove the 3 screws from the rear control cover WARNING and remove the cover. 5. Remove 6 screws of PCB assembly and separate ELECTRICAL SHOCK HAZARD PCB assembly.
COMPONENT ACCESS REMOVING THE CONTROL POWER SUPPL REMOVING THE CONTROL POWER SUPPL AND POWER CONTROL BOARD (PCB) AND POWER CONTROL BOARD (PCB) 5. To remove the control power supply: WARNING a) Disconnect 2 connectors. b) Remove the two screws. ELECTRICAL SHOCK HAZARD Disconnect power before servicing the range.
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COMPONENT ACCESS REMOVING THE SURF ACE ELEMENTS REMOVING THE SURF ACE ELEMENTS AND THE CERAMIC GLASS COOKT AND THE CERAMIC GLASS COOKT Step. 5 WARNING Protect the cooktop surface ELECTRICAL SHOCK HAZARD and turn the assembly over. Disconnect power before servicing the range. Replace all panels before operating range.
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COMPONENT ACCESS REMOVING THE DOOR LA TCH & DOOR SWITCH REMOVING THE DOOR LA TCH & DOOR SWITCH b) Remove the door latch from the burner box WARNING and unhook the actuating rod. ELECTRICAL SHOCK HAZARD Unhook Disconnect power before servicing the range. Actuating Replace all panels before operating range.
COMPONENT ACCESS REMOVING THE BROIL ELEMENT REMOVING THE BROIL ELEMENT b) Pull the element forward so that you can WARNING access the terminals and disconnect the wires. ELECTRICAL SHOCK HAZARD Terminals Disconnect power before servicing the range. Replace all panels before operating range. Failure to do so can result in death or electrical shock.
COMPONENT ACCESS REMOVING THE HIDDEN BAKE ELEMENT REMOVING THE HIDDEN BAKE ELEMENT 1. Unplug range or disconnect power. 7. Bend the insulation glass fiber up. 2. Pull the range out of its mounting location so that you can access the rear of the unit. 3.
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COMPONENT ACCESS REMOVING THE CONVECTION ELEMENT AN BLADE AND F AN MOT REMOVING THE CONVECTION ELEMENT AN BLADE AND F AN MOT 1. Disconnect power and remove oven racks. 8. To remove Fan motor assembly, disconnect wire connection and remove the three bracket 2.
COMPONENT ACCESS REMOVING THE OVEN LIGHT & SOCKET ASSEMBL REMOVING THE OVEN LIGHT & SOCKET ASSEMBL CAUTION WARNING Be careful not to scratch or chip the oven liner ELECTRICAL SHOCK HAZARD paint when you remove the oven light socket in Disconnect power before servicing the range.
COMPONENT ACCESS REMOVING THE LA TCH DRIVE ASSEMBL REMOVING THE LA TCH DRIVE ASSEMBL DOOR LOCKING MECHANISM WARNING The door lock assembly is located at the back side ELECTRICAL SHOCK HAZARD of range. Disconnect power before servicing the range. The structural elements are as below. Replace all panels before operating range.
COMPONENT ACCESS REMOVING THE OVEN TEMPERA TURE SENSORS REMOVING THE OVEN TEMPERA TURE SENSORS 5. To remove an oven temperature sensor, WARNING disconnect the connector from the main harness and remove the two mounting screws in oven ELECTRICAL SHOCK HAZARD cavity.
COMPONENT ACCESS REMOVING THE ST ORAGE DRA REMOVING THE ST ORAGE DRA To Replace the Storage Drawer: WARNING 1. Replace shield on the right glide of the drawer body. ELECTRICAL SHOCK HAZARD 2. Pull the bearing glides to the front of the chassis Disconnect power before servicing the range.
COMPONENT ACCESS REMOVING & REPLACING THE LIFT -OFF OVEN DOOR REMOVING & REPLACING THE LIFT -OFF OVEN DOOR To replace the door: CAUTION Step. 1 The door is very heavy. Be careful when Firmly grasp both removing and lifting the door. Do not lift the door sides of the door by the handle.
COMPONENT ACCESS REMOVING THE OVEN DOOR HANDLE & GLASS REMOVING THE OVEN DOOR HANDLE & GLASS 6. To remove the door handle & trim (for stainless model) WARNING a) Remove the 4 door handle screws and lift the door handle off door trim and slide up the door handle. ELECTRICAL SHOCK HAZARD Disconnect power before servicing the range.
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COMPONENT ACCESS 7. To remove a hinge hanger assembly: d) Lift the inner oven door glass and bracket a) Remove the 2 top liner screws assembly out of the door liner. (See step 3 on page 3-14) b) Place the door liner assembly on a padded work surface with the hinge hangers over the edge.
COMPONENT ACCESS REMOVING THE OVEN DOOR GASKET REMOVING THE OVEN DOOR GASKET 3. Pull the ends of the gasket out of the liner holes. WARNING Liner Hole ELECTRICAL SHOCK HAZARD Disconnect power before servicing the range. Replace all panels before operating range. Failure to do so can result in death or electrical shock.
COMPONENT ACCESS REMOVING A SIDE P ANEL REMOVING A SIDE P ANEL 7. Remove the two screws from the left or right side WARNING panel. ELECTRICAL SHOCK HAZARD Disconnect power before servicing the range. Replace all panels before operating range. Failure to do so can result in death or electrical shock.
COMPONENT TEST Before testing any of components, perform the following checks: NOTE: 1. The most common cause for control failure is corrosion on connectors. Therefore, disconnecting and reconnecting wires will be necessary throughout test procedures 2. ALL units in the first few days of use should be checked for mis-wiring or loose connections 1.
Components Test procedures Results Normal: Approximately Door locking Motor 1. Refer to page 3-10 for the servicing procedure 2.6 kΩ ± 10% 2. Measure the resistance If not replace (Multiple meter scale: R x 1000) Abnormal: Infinite(open) below 5Ω (shorted) Door latch Door latch Micro Switch...
Components Test procedures Results Normal: Approximately Oven Sensor 1. Refer to page 3-11 for the servicing procedure 1.09 kΩ ± 10% 2. Measure the resistance after cooling down If not replace (Multiple meter scale: R x 1000) NOTE: Ω Value was tested at room temperature (77F/25˚C) NOTE: Oven sensor is so sensitive to temperature...
Components Test procedures Results Normal: Below 5 Ω. Oven lamp 1. Measure the resistance after cooling down If not replace (Multiple meter scale: R x1)
Components Test procedures Results Single surface units: 1. Refer to page 3-4 for the servicing procedure Right Front (RF), 2. Set the Multiple meter scale to the R x 1 Left Rear (LR) 3. Disconnect wires from cook-top elements 4. Touch the ohmmeter test leads to the element Right Rear(RR) terminal and 1A.
Components Test procedures Results Center Rear(CR) 1. Refer to page 3-4 for the servicing procedure Element 2. Set the Multiple meter scale to the R x 1 ;Warming Zone 3. Disconnect wires from CR elements 4. Touch the ohmmeter test leads to the element terminal and 1A.
Components Test procedures Results Dual surface element 1. Refer to page 3-4 for the servicing procedure : Left Front(LF) 2. Set the Multiple meter scale to the R x1 3. Disconnect wires from cook-top elements 4. Touch the ohmmeter test leads to the (E1 & 1A) and (E2 &...
COMPOSITION OF CONTROL Main PCB (P/N : 6871W1N002A) Front Front Back Back Controller assembly Cook top display PCB (P/N : 6871W1N010B) Front Back Key pad assembly Oven relay PCB (P/N : 6871W1N012B) Front Back Front Back PCB case assembly...
COMPOSITION OF CONTROL Main PCB Main PCB P/N : 6871W1N002A Main function ▶ Supply a DC power source (GND,5V,12V(Vry(oven heater switching)),Vdisp(5V)) ▶ Supply a DC power source (GND,12V(Vry(cooktop heater switching voltage)) ▶ Oven heater control (DLB / Broil / Bake) ▶...
COMPOSITION OF CONTROL Cook-top display PCB Cook-top display PCB P/N : 6871W1N010B Main function ▶ Single radiant surface elements -Right Rear, Left Rear, Left Front- power level indication ▶ Dual radiant surface elements -Right Front inner,outer- power level indication ▶ Dual radiant surface element size indication-Right Front inner, outer ▶...
FAILURE MODE FLOW CHART No display (No power) Blank display Enter key input Check the thermal fuse Some beep (See the page 3-1) sound? Check AC input voltage of Main PCB Cook-top display - Main PCB CN3 (pin 1 and 3) blank? (Go to page 6-3) Check voltage –...
FAILURE MODE FLOW CHART No display (No power) Blank display Enter key input Check the thermal fuse Some beep (See the page 3-1) sound? Check AC input voltage of Main PCB Oven display blank? - Main PCB CN3 (pin 1 and 3) (Go to page 6-3) Replace the main PCB(002A)
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FAILURE MODE FLOW CHART No display (No power) Check the harness of between L1~N Is it 120V AC? Normal? Disconnect power Replace the defective harness Check the power transformer (Refer to the below) Secondary Primary Fig.1 Side Lead Color DCR(Ω) black ~ white 25 ~ 28 yellow ~ yellow...
FAILURE MODE FLOW CHART Oven does not heat Code Error mode Operation Times/sampling No heating If current oven temperature does not exceed 150˚F and During cook less than start temperature over 5 minutes on preheating, where door is closed. (except proof and cook & warm ) No Heating(Main Oven) Disconnect power Check for loose connections at bake, broil,...
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FAILURE MODE FLOW CHART Oven does not heat Normal? Replace the bake heater Check the broil heater (measure the resistance after cooling down) Normal: approximately 14Ω Normal? Replace the broil heater Continued on the next page...
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FAILURE MODE FLOW CHART Oven does not heat Check for loose oven sensor connector Normal? Reconnect Check the oven sensor (measure the resistance after cooling down) Normal: approximately 1.09kΩ Normal? Replace the oven sensor Replace the oven relay PCB (012B) Normal? Replace the main PCB(002A) For further check of main PCB...
FAILURE MODE FLOW CHART Cook-top does not heat No heating (All or a part of cook-top heaters) Disconnect power Check for loose connection at board (002A PCB) to cook top heaters. Normal? Reconnect. If defective harness, replace or fix Continued on the next page...
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FAILURE MODE FLOW CHART Cook-top does not heat Remove the main PCB(002A) harness and pull the main PCB(002A) forward from the PCB case Inspect the main PCB(002A) Wide pattern(Live part) blown out Repairable Normal? by yourself? Repair and fix Replace the main PCB(002A)
FAILURE MODE FLOW CHART Oven lamp does not operate Oven lamp does not operate Disconnect power Check for loose connection of oven lamp terminal and harness Normal? Reconnect Check for loose connector (main PCB CN1) If defective harness, replace or fix Normal? Reconnect Check the oven lamp (measure the resistance)
FAILURE MODE FLOW CHART No key input Key does not input Reconnect the main PCB connector CN10 and CN11 more than two times Normal? Some keys or All keys? Some Replace the main PCB(002A) Replace the main PCB Normal? Replace the keypad assembly 6-10...
FAILURE CODES DISPLAY CAUSE CORRECTIVE ACTION WARNING SHOWS Main oven A. Perform step 1 through 2 above • Disconnect power supply cord from the outlet heating B. Open the back panel and check continuity of the before servicing error sensor, heater (bake, broil) and Control(PCB) C.
F-CODE FLOW CHART Key short error F-1 error Code Error mode Operation Times/sampling Key shorted If a key pad is continuously short for 60 seconds. Key short error (F-1) Plugged out the power, remove keypad-tail and check F-1 error recur or not, after plugging in the power recur? Disconnect power...
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F-CODE FLOW CHART Door lock system error F-2 error Code Error mode Operation Times/sampling Door Lock Fail In case of Door Lock Failure → Just after self-clean start, the door lock motor starts to rotate. During that time if the door lock switch does not operate properly after rotating twice, then supervising circuit detects a Door Lock failure and the F-2 error code appears.
F-CODE FLOW CHART Door lock system error F-2 error Normal? Replace the micro switch Check the door locking motor (measure the resistance) normal: approximately 2.6kΩ abnormal: infinite or below 5 Ω Normal? Replace the door locking motor Check for loose connector (Front) (main PCB CN4) Front Normal? Reconnect...
F-CODE FLOW CHART Door lock system error F-2 error Inspect connector pin solder of CN4 (Back) (main PCB CN4) Back ※ If pin solder is cracked, repair and re-use Cracked? Replace Repair and fix...
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F-CODE FLOW CHART Main oven sensing error F-3, F-4 error Code Error mode Operation Times/sampling Opened Sensor Oven Thermistor remains open for over During cook 1 min, after cook starts Shorted Sensor Oven Thermistor is short for over 1 min During cook after cook starts Main oven sensing failed...
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F-CODE FLOW CHART Main oven sensing error F-3, F-4 error Check for loose connector. (Front) (main PCB CN6) Check for loose connector (main PCB CN6) and look for harness terminals damaged or not Reconnect and Normal? replace the bad harness Remove the main PCB (002A) harness and pull the PCB (002A) forward from the PCB case Inspect connector pin solder of CN6 (Back) (main PCB CN6)
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F-CODE FLOW CHART Oven too hot error F-9 error Code Error mode Operation Times/sampling Oven hot Oven temperature is over 650˚F During cook continuously during 2 minutes on cooking. (Not self clean mode) Oven is too hot (F-9) Disconnect power / Remove the oven relay PCB(012B) harness and pull the oven relay PCB(012B) forward from case Check for a welded bake relay.
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F-CODE FLOW CHART Oven too hot error F-9 error Check for a welded broil relay. (measure the resistance) Welded Normal Continuity Infinite Normal? Replace the oven relay PCB(012B) Replace the main relay PCB(002A)
TROUBLE SHOOTING PROBLEMS POSSIBLE CAUSES & FAULTS SOLUTIONS Oven not operating. • Bad power control board (PCB) • Test and/or replace PCB ➞ Refer to the page 6-1~6-3 • Power outage • Verify power is present at unit. • Verify that the circuit breaker is not tripped •...
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TROUBLE SHOOTING PROBLEMS POSSIBLE CAUSES & FAULTS SOLUTIONS Electronic timer will not • Failed main power control board • Replace power control board(PCB) accept Programming. Electronic timer will not • Failed main power control board • Replace power control board(PCB) accept Programming.
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TROUBLE SHOOTING PROBLEMS POSSIBLE CAUSES & FAULTS SOLUTIONS Oven door sagging on one • Hinge loose or out of position to • Adjust hinges or replace hinges side oven liner Door does not close • Broken or misadjusted door spring •...
SCHEMATIC DIAGRAM For Model: LRE30451SW / SB / ST NOTE:Schematic diagram shows door WARNING switch In the cook position with the oven POWER MUST BE door open and elements off. DISCONNECTED BEFORE SERVICING THE APPLIANCE RADIANT COOK-TOP Wattage RR:1200W LR:1200W...
2.Check for loose wiring or mis-wiring within electric range. NOTE: The following individual circuits are for use in diagnosis, and are shown in the ON position. For Model: LRE30451SW / SB / ST BAKE / COOK & WARM / PROOF...
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For Model: LRE30451SW / SB / ST SELF CLEANING CLOCK DISPLAY ON...
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For Model: LRE30451SW / SB / ST CONV. BAKE / CONV. ROAST CR(Warming Zone) RR Cook-top Element...
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For Model: LRE30451SW / SB / ST LR Cook-top Element RF Cook-top Element LF Cook-top Element...
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#EV# INTRODUCTION (II) * Check the Rating Model No. SVC Model Factory Model Suffix LRE30451ST LFRF0222S ASTELGA LRE30451ST / 01 LFRF0222S ASTLLGA LRE30451ST / 02 LFRF0222S AS1LLGA LRE30451ST / 03 LFRF0222S AS2LLGA CONTROLLER PARTS COOKTOP PARTS DOOR PARTS CAVITY PARTS DRAWER PARTS -10-2-...
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#EV# DOOR PARTS (II) For Model: W224 1023 1000 1703 1028 W149 1024 W222 1018 1704 1024 W146 W146 W149 1015 W149 W101 1401 W149 1704 1401 1020 1021 1009 -10-4-...