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Internal Use Only 30” ELECTRIC CONVECTION BUILT-IN OVEN SERVICE MANUAL MODEL: LSWS306ST LSWS307ST LSWS309BD LSWS300BD CAUTION BEFORE SERVICING THE UNIT, READ THE SAFETY PRECAUTIONS IN THIS MANUAL. December, 2015 P/NO : MFL37118348 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 READ ALL INSTRUCTIONS BEFORE USE 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 READ ALL INSTRUCTIONS BEFORE USE SAFETY PRECAUTIONS • Be certain all packing materials are removed • Be certain your appliance is properly installed from the appliance before operating. and grounded by a qualified technician. Keep plastics, clothes, and paper away from •...
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GENERAL READ ALL INSTRUCTIONS BEFORE USE • Before replacing your oven light bulb, CHILD SAFETY switch off the electrical power to the oven at the main fuse or circuit breaker panel. WARNING Failure to do so can result in severe personal injury, death, or electrical shock.
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GENERAL READ ALL INSTRUCTIONS BEFORE USE SAFETY WHEN CLEANING • Do Not Clean Door Gasket. The door gasket is • Important Instruction. In the event the self clean error code F is displayed, and error essential for a good seal. Care should be taken not to rub, damage, or move the gasket.
GENERAL MODEL & SERIAL NUMBER LABEL AND TECH SHEET LOCATION The Model/Serial Number label and Tech Sheet locations are shown below. Model & Serial Number Location Tech Sheet Location...
GENERAL SPECIFICATIONS Product Specification List Items Specifications Remarks Model name LSWS305ST / LSWS309BD North American market LSWS307ST /LSWS300BD Rating power source 240 V~ 60 Hz Single phase & 4-wires Heat source Sheath heater & Carbon heater Max power 120/240V : 4.1 KW 120/208V : 3.1 KW Max input current 17.3 A...
USING YOUR OVEN GENERAL INFORMATION Cooking Guide Rating Label Refer to the owners manual for recommendations Model numbers are recorded on the rating label. of times and temperatures. Times, rack position, Rating label is located on the lower left bottom and temperatures may vary depending on area of the controller.
USING YOUR OVEN CONTROL PANEL FEATURES LSWS306ST LSWS309BD READ THE INSTRUCTIONS CAREFULLY BEFORE USING THE OVEN. For satisfactory use of your oven, become familiar with the various features and functions of the oven as described below. COMMON FUNCTION OVEN CONTROL 1.
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USING YOUR OVEN CONTROL PANEL FEATURES LSWS307ST LSWS300BD READ THE INSTRUCTIONS CAREFULLY BEFORE USING THE OVEN. For satisfactory use of your oven, become familiar with the various features and functions of the oven as described below. COMMON FUNCTION OVEN CONTROL 1.
USING YOUR OVEN 1. SETTING THE CLOCK 3. Adjust the time/temp. knob to the desired setting. (12h, 24H). Press and hold Select Time/Temp. Knob 4. Press the START button. START "OFF" (Set the desired time) COOK TIME 2) CONVECTION AUTO CONVERSION 1.
USING YOUR OVEN 14. TIMED COOK, DELAYED TIMED COOK 7) BEEPER VOLUME 1. Select all oven mode knob to OFF position. Select Time/Temp. Knob 2. Press and hold the START TIME button for 3 START "BAKE" (Set the desired temp.) seconds.
DISASSEMBLY INSTRUCTIONS This section instructs you on how to service each component inside the range. The components and their locations are shown below. COMPONENT LOCATIONS Upper Oven Light Upper Door L tch Oven Sen or Upper Door Switch onvection oto r onvection e ter inge nger...
DISASSEMBLY INSTRUCTIONS REPLACING THE CONTROL PANEL AND RELATED COMPONENTS 6. Disconnect the connectors from PCB assembly WARNING and separate control panel carefully. • ELECTRIC SHOCK HAZARD - Unit must be disconnected from electrical outlet when making repairs, replacements, adjustments. Replace all panels before operating oven.
DISASSEMBLY INSTRUCTIONS Hook Hook Motor Motor Unlock Unlock Hook Motor 2) Disconnect the connectors from PCB assembly Hook Hook Hook Motor Motor and separate Main PCB assembly. Micro Switch Micro Switch Motor Lock Lock Unlock Unlock Unlock Unlock Micro Switch Lock Micro Switch Lock...
DISASSEMBLY INSTRUCTIONS REPLACING OVEN CAVITY COMPONENTS 1) To remove the broil element: WARNING a. Remove the 4 screws from the front and rear brackets. • ELECTRIC SHOCK HAZARD - Unit must be disconnected from electrical outlet when making repairs, replacements, adjustments.
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DISASSEMBLY INSTRUCTIONS 4) To remove the halogen lamp & socket assembly b. Remove the 3 convection element screws. (The convection element is fragile. Care a. There are three halogen lamp & socket should be taken to avoid any risk of injury) assembly in the oven cavity.
DISASSEMBLY INSTRUCTIONS REPLACING OTHER ELECTRICAL COMPONENTS Vent motor WARNING Thermal limiter • ELECTRIC SHOCK HAZARD - Unit must be disconnected from electrical outlet when making repairs, replacements, adjustments. Replace all panels before operating oven. Failure to do so can result in death or electrical shock.
DISASSEMBLY INSTRUCTIONS COOLING FAN (BLOWER) 4) Squeeze tabs on switch and slide through the front. • Self Clean Mode: The cooling fans can Disconnect the wires from terminals. operate at 2 different speeds based on temperature. If the temp is above 482°F/250°C the fans will operate on high.
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DISASSEMBLY INSTRUCTIONS 1) To Remove Thermal Limiter (Double Line Brake 3) To remove the hidden bake element Upper), remove the screw and 2 wire leads. a. Remove the Vent cover, Barrier bracket. THERMAL LIMITER • To shut down the heaters The thermostats are located at the back of the oven next to each broil element and wired in series with each Double Line Break relay.
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DISASSEMBLY INSTRUCTIONS d. Bend the insulator up and remove the 1 screw. e. Carefully pull the hidden bake element and its BAKE HEATER_COVER out of the oven. f. When replacing the Bake Element cover use the 5 screws provided.
DISASSEMBLY INSTRUCTIONS REMOVING & REINSTALLING THE LIFT-OFF OVEN DOOR To replace the door: CAUTION 1. Firmly grasp The door is very heavy. Be careful both sides of the door at the when removing and lifting the door. top. Do not lift the door by the handle. Hinge arm Hinge arm 2.
DISASSEMBLY INSTRUCTIONS REMOVING THE OVEN DOOR HANDLE & GLASS 6. To remove the door handle & trim. CAUTION a. Remove 2 screws for handle and replace. • Be careful when you work on the b. Slide Door trim up and off. electric oven handling the sheet metal part.
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DISASSEMBLY INSTRUCTIONS 5) Lift the COVER_INNER-2 off the door liner. 6) Lift the hinge out of the door liner slot. To remove the oven door glass assembly: 7) Lift the COVER_INNER-1 off the door liner. COVER_INNER-1 8) Lift the inner oven door glass and bracket assembly out of the door liner.
DISASSEMBLY INSTRUCTIONS REMOVING THE OVEN DOOR GASkET 1. Remove oven door 3. Pull the ends of the gasket out of the liner holes. 2. Pull the oven door gasket clips out of the liner Liner Hole holes until all of the clips are removed. Door gasket REASSEMBLY NOTE: When reinstalling the new gasket, make sure that all of the clips are seated in...
COMPONENT TEST Before testing any 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. If this is a new product check all connections before replacing parts. 1.
Components Test procedures Results Normal: Approximately 2550 Ω Door locking Motor 1. Refer to page 3-10 for disassembly Replace if: Infinite (opened) 2. Measure the resistance below 5 Ω (shorted) (Multiple meter scale: R x 1000) Door latch Door latch Door locking micro 1.
Components Test procedures Results Normal: Approximately Oven Thermistor 1. Refer to page 3-5 for disassembly 1090 Ω 2. Measure the resistance after cool down Replace if: Infinite (opened) (Multiple meter scale: R x 1000) below 10 Ω (shorted) NOTE: Ω Value should be tested at room temperature (77F/25˚C) NOTE: After checking for the continuity of switch, make sure to reconnect leads...
Components Test procedures Results Normal: Approximately Broil Element 1. Refer to page 3-4 for disassembly Inner: 22.5 Ω 2. Measure the resistance after cool down Outer: 36.9 Ω (Multiple meter scale : R x 1) Replace if: Infinite (opened) NOTE: Outer Broil element use Outer yellow and Blue terminals to check resistance.
COMPOSITION OF CONTROL LSWS306ST LSWS309BD Wiring Diagram AC INPUT Relay P.C.B. CN01 BLOWER HI BLOWER BLOWER CONV. CONV. FAN DOOR MOTOR DOOR PRI. SEC. MOTOR CN02 OVEN LAMP OVEN TRANSFORMER OVEN LAMP LAMP OVEN LAMP OVEN LAMP RY11 BAKE BAKE HEATER RY12 CONV.
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COMPOSITION OF CONTROL LSWS307ST LSWS300BD Wiring Diagram AC INPUT Relay P.C.B. CN01 BLOWER HI BLOWER BLOWER CONV. CONV. FAN DOOR MOTOR DOOR PRI. SEC. MOTOR CN02 OVEN LAMP OVEN TRANSFORMER OVEN LAMP LAMP OVEN LAMP OVEN LAMP RY11 BAKE BAKE HEATER RY12 CONV.
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COMPOSITION OF CONTROL LSWS306ST Main PCB ( P/N : EBR80108104) LSWS309BD Composition of control Oven Relay PCB ( P/N : EBR64624604) VFD Module ( P/N : EAJ62608101) Touch PCB ( P/N : EBR82172601) Time & Temp Encoder PCB ( P/N : EBR80595801)
DIAGNOSIS THROUGH SCHEMATIC Sequence of SVC Test Mode To enter the test mode, follow these steps: (1) press the any button (2) press the OVEN LIGHT and turn right Time & Temp Encoder at the same time (3) press the OVEN LIGHT and turn right Time & Temp Encoder again Model Option Software version (4) Select the “t0”...
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DIAGNOSIS THROUGH SCHEMATIC • SW Version • Active Load Icon Current inspecting Relay’s information is displayed (6) Whenever you input the START button, the relay operation sequence should be as seen below. ※ Relay Operation Sequence RY11 RY13 RY14 RY12 RY19 Inner Conv.
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DIAGNOSIS THROUGH SCHEMATIC LSWS306ST LSWS309BD Basic Check Summary Symptom : Oven hot(F6) -. Check: All heater relays are AC INPUT open/shorted Symptom : no heating(F9) Symptom : Door lock fail (F10) -. Check : All heater relays and DLB relay are openv -.
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DIAGNOSIS THROUGH SCHEMATIC LSWS307ST LSWS300BD Basic Check Summary Symptom : Oven hot(F6) -. Check: All heater relays are AC INPUT open/shorted Symptom : no heating(F9) Symptom : Door lock fail (F10) -. Check : All heater relays and DLB relay are openv -.
TROUBLESHOOTING Check the Failure Code ■ When the oven has a malfunction while cooking, - Cooking will be canceled and log data of F-code will be recorded in EEPROM. - F-code will not display during normal operation. ■ Check the failure code following these steps. 1.
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TROUBLESHOOTING Failure Code Summary Code Description explanation Check point 1.Wiring Sensor open Oven Thermistor is open 2.Oven Sensor 1.Wiring Sensor short Oven Thermistor is shorted. 2.Oven Sensor 1. If ‘25 key short’ occurred 3 times in 90 sec- 1.Wiring onds. 2.
TROUBLESHOOTING Symptom Check Point 1. Power Failure 1.Check Electrical Wiring (Dead) 2. No Display 2.Check the Main PCB Input Voltage with CN1 Thermostat CN01 Main PCB...
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TROUBLESHOOTING Power Failed (Dead), No display? Plug in the unit Check the AC input of Main Replace the PCB. Check the button beep. Main PCB - Main PCB CN01 Replace the Touch the Clear button, (Pin 1 and 3) Main PCB Can hear the beep sound? 120V AC? Check the connection of...
TROUBLESHOOTING Symptom Check Point 1. No heating 1.Check Electrical Wiring 2. F9 2.Check Heater’s Resistance. 3.Check the Sensor.
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TROUBLESHOOTING Symptom Check Point 1. No heating 1.Check Electrical Wiring 2. F9 2.Check Heater’s Resistance. 3.Check the Sensor. CN32...
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TROUBLESHOOTING Oven does NOT heat, F9 Is the connection of heater Replace the Unplug the unit normal? Failed heater Reconnect. Measure the resistance Is the Connector disconnected If defective harness, of each heater. or loose? Replace or fix (The resistance is shown (1) Between Main PCB and below) Relay PCB (Main : CN51...
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TROUBLESHOOTING Unplug the unit Range Of resistance Resistance[Ω] Heater Approximately Replace the Is the resistance of defective Inner Broil 22.5 thermistor normal? Thermistor Outer Broil 36.9 Check: Bake 22.5 Pins 4 and 5 of CN32 in main PCB Convection 27.9 Normal- approximately 1.09kΩ...
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TROUBLESHOOTING Symptom Check Point 1. Door Lock System 1. Check the Electric wiring Failure 2. Check the Motor’s Resistance 2. F10 3. Check the Relay PCB (Door Lock Relay) CN32...
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TROUBLESHOOTING Symptom Check Point 1. Door Lock System 1. Check the Electric wiring Failure 2. Check the Motor’s Resistance 2. F10 3. Check the Relay PCB (Door Lock Relay) 7-10...
TROUBLESHOOTING Door Lock System Failure,F10? Plug in the unit Unplug the unit Note : Is the Connector disconnected Reconnect. Just after self-clean start, the door lock motor or loose? If defective harness, starts to rotate. Check the following : replace or fix During this time if the door lock switch does (1) Between Main PCB and NOT operate properly after rotating twice, then...
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TROUBLESHOOTING Is the door lock switch (micro Replace the micro switch) normal? switch measure the resistance of door lock switch normally open type Abnormal Normal Is the resistance of the lock Replace the lock motor normal ? motor measure the resistance of lock motor Normal : approximately 2.6kΩ...
TROUBLESHOOTING Symptom Check Point 1. Sensing Fail 1.Check the Electrical Wiring 2. F1 2.Check the Test Mode 3. F2 3.Check the Sensor’s Resistance CN32 7-13...
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TROUBLESHOOTING Sensing Fail, F1, F2? Plug in the unit Reconnect or adjust Is the resistance of Replace the Is the Connector disconnected the connection thermistor normal? defective or loose? Thermistor (1) Sensor connection Check: (2) CN32 of Main PCB Pins 5 and 6 of CN32 in main PCB Normal- approximately 1.09kΩ...
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TROUBLESHOOTING Plug in the unit Is the value of thermistor Go to No 1 normal? (Refer below) Check with the test mode To enter the test mode, follow these steps: 1) Press the any button 2) Press the OVEN LIGHT and turn right Lower Time &...
TROUBLESHOOTING Symptom Check Point 1. Oven hot 1.Check the Resistance of the Relay. 2. F6 2.Check the Sensor’s Resistance 7-16...
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TROUBLESHOOTING Symptom Check Point 1. Oven hot 1.Check the Resistance of the Relay. 2. F6 2.Check the Sensor’s Resistance CN32 7-17...
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TROUBLESHOOTING Oven hot, F6? Is the Heater relay normal? Replace the Relay PCB Measure the resistance of heater relay and Live1. Unplug the unit Normal: infinite Abnormal : shorted Replace the Is the resistance of defective thermistor normal? Thermistor Bake Check: Heater Relay Pins 5 and 6 of CN32 in main...
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TROUBLESHOOTING Plug in the unit Is the DLB relay normal? Replace the Relay Measure the resistance Is the value of thermistor Replace the Main Normal: infinite normal? (Refer below) Abnormal : shorted Check with the test mode To enter the test mode, follow these steps: (1) press the any button (2) press the OVEN LIGHT and turn right Lower...
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TROUBLESHOOTING Symptom Check Point 1. Key not working 1. Check the Door Locking System. 2. F3 Error 2. Check the Electrical Wiring. CN44 7-20...
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TROUBLESHOOTING Plug in the unit F3 error (Button short error) Or button does not input Replace the Control panel. (With Glass Touch PCB) Unplug the unit And then check button operation using key test mode Reconnect or adjust the Check the connecting states connection between Touch PCB and To enter the test mode, follow these steps:...
Appendix. kEY OPERATION TEST SEQUENCE ■ How to check button operation 1. Keys should be accessed according to the above sequence and check the beep sound when key is accessed If Key is the normal operation will be the number that corresponds to the Key displayed on the VFD 2.
SCHEMATIC DIAGRAM LSWS306ST LSWS309BD AC INPUT Relay P.C.B. CN01 BLOWER HI BLOWER BLOWER CONV. CONV. FAN DOOR MOTOR DOOR PRI. SEC. MOTOR CN02 OVEN LAMP OVEN TRANSFORMER OVEN LAMP LAMP OVEN LAMP OVEN LAMP RY11 BAKE BAKE HEATER RY12 CONV.
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SCHEMATIC DIAGRAM LSWS307ST LSWS300BD AC INPUT Relay P.C.B. CN01 BLOWER HI BLOWER BLOWER CONV. CONV. FAN DOOR MOTOR DOOR PRI. SEC. MOTOR CN02 OVEN LAMP OVEN TRANSFORMER OVEN LAMP LAMP OVEN LAMP OVEN LAMP RY11 BAKE BAKE HEATER RY12 CONV. CONV.
STRIP CIRCUITS Complete the following steps before checking electric oven circuit : 1.Check the line voltage, household fuse or circuit breaker. 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. Full Broil mode RY11 BAKE...