Daewoo KOC-1B4K5S, KOC-1B4K Service Manual

Service Manual

Microwave Oven

Model: KOC-1B4K0S

S/M NO. : C1B4K0S001

DAEWOO ELECTRONICS CO., LTD.

http://svc.dwe.co.kr Apr. 2001

✔

Caution

: In this Manual, some parts can be changed for improving, their performance without notice in the parts list. So, if you need the latest parts information,please refer to PPL(Parts Price List) in Service Information Center (http://svc.dwe.co.kr).

PRECA UTIONS T O BE OBSERVED BEFORE AND DURING SER VICING T O AVOID POSSIBLE EXPOSURE T O EXCESSIVE MICROW AVE ENERGY

(a)Do not operate or allow the oven to be operated with the door open. (b)Make the following safety checks on all ovens to be serviced before activating the magnetron or other

microwave source, and make repairs if necessary: (1) Interlock operation, (2) Proper door closing, (3) Seal and sealing surfaces (arcing, wear, and other damage), (4) Damage to or loosening of hinges and latches (5) Evidence of dropping or abuse.

(c)Before turning on power to the microwave oven for any service test or inspection within the microwave

generating compartments, check the magnetron, wave guide or transmission line, and cavity for proper alignment, integrity, and connections.

(d) Any defective or misadjusted components in the interlock, monitor, door seal and microwave

generation and transmission systems shall be repaired, replaced, or adjusted by procedures described in this manual before the oven is released to the owner.

A microwave leakage check to verify compliance with the Federal performance standard should be performed on each oven prior to release to the owner.

TABLE OF CONTENTS

1. SAFETY AND PRECAUTIONS....................................................................................................................................2

2. SPECIFICATIONS ........................................................................................................................................................3

3. EXTERNAL VIEW.........................................................................................................................................................3

3-1. OUTER DIMENSION..........................................................................................................................................3

3-2. FEATURE DIAGRAM .........................................................................................................................................4

4. INSTALLATION............................................................................................................................................................5

5. CONTROL PANEL .......................................................................................................................................................6

6. DISASSEMBLY AND ASSEMBLY..............................................................................................................................7

7. INTERLOCK MECHANISM AND ADJUSTMENT.....................................................................................................17

8. TROUBLE SHOOTING GUIDE..................................................................................................................................18

9. MESUREMENT AND TEST .......................................................................................................................................24

9-1. MEASUREMENT OF THE MICROWAVE POWER OUTPUT........................................................................24

9-2. MICROWAVE RADIATION TEST....................................................................................................................25

9-3. COMPONENT TEST PROCEDURE................................................................................................................26

9-4. COMPONENT ACTION....................................................................................................................................27

10. WIRING DIAGRAM...................................................................................................................................................28

11. EXPLODED VIEW AND PARTS LIST ..................................................................................................................29

11-1. DOOR ASSEMBLY.........................................................................................................................................29

12-2. CONTROL PANEL ASSEMBLY.....................................................................................................................29

13-3. TOTAL ASSEMBLY........................................................................................................................................29

12. PRINTED CIRCUIT BOARD ....................................................................................................................................33

13. P.C.B CIRCUIT DIAGRAM.......................................................................................................................................37

1. SAFETY AND PRECA UTIONS

1. FOR SAFE OPERATION

Damage that allows the microwave energy (that cooks or heats the food) to escape will result in poor cooking and may cause serious bodily injury to the operator. IF ANY OF THE FOLLOWING CONDITIONS EXIST, OPERATOR MUST NOT USE THE APPLIANCE. (Only a trained service personnel should make repairs.)

(1) A broken door hinge. (2) A broken door viewing screen. (3) A broken front panel, oven cavity. (4) A loosened door lock.

(5) A broken door lock. The door gasket plate and oven cavity surface should be kept clean. No grease, soil or spatter should be allowed to build up on these surfaces or inside the oven. DO NOT ATTEMPT TO OPERATE THIS APPLIANCE WITH THE DOOR OPEN. The microwave oven has concealed switches to make sure the power is turned off when the door is opened. Do not attempt to defeat them. DO NOT ATTEMPT TO SERVICE THIS APPLIANCE UNTIL YOU HAVE READ THIS SERVICE MANUAL.

2. FOR SAFE SERVICE PROCEDURES.

1. If the oven is operative prior to servicing, a microwave emission check should be performed prior to servicing the

oven.

2. If any certified oven unit is found to servicing, a microwave emission check should be performed prior to servicing the

oven.

(1) inform the manufacturer, importer or assembler,

(2) repair the unit at no cost to the owner,

(3) attempt to ascertain the cause of the excessive leakage,

(4) tell the owner of the unit not to use the unit until the oven has been brought into compliance.

3. If the oven operates with the door open, the service person should tell the user not to operate the oven and contact

the manufacturer immediately.

IMPORTANT

The wire in this mains lead coloured in accordance with the following code.

Green-and-yellow : Earth Blue : Neutral

Brown : Live As the colours of the wires in the mains lead of this appliance may not correspond with the coloured markings identifying the terminals in your plug, proceed as follows: The wire which is coloured green-and-yellow must be connected to the terminal in the plug which is marked with the letter ‘E’, earth symbol or coloured green-and-yellow. The wire which is coloured blue must be connected to the terminal which is marked with the letter ‘N’ or coloured black. The wire which is coloured brown must be connected to the terminal which is marked with the letter ‘L’ or coloured red.

NOTE : This oven is designed for counter-top use only.

3. EXTERNAL VIEW

2. SPECIFICATIONS

MODEL KOC-1B4K POWER SUPPLY 230V~50HZ, SINGLE PHASE WITH EARTHING

MICROWAVE 1500W POWER GRILL 1600W CONSUMPTION COMBECTION 2300W

COMBINATION 3100W MICROWAVE ENERGY OUTPUT 1000W(IEC705) MICROWAVE FREQUENCY 2450MHz OUTSIDE DIMENSIONS (W X H X D) 560X344X543mm (22.0X13.5X21.3 in.) CAVITY DIMENSIONS (W X H X D) 368.5X246X376.5mm (14.5X9.7X14.8 in.) NET WEIGHT APPROX. 21.5kg (47.6 lbs.) TIMER 60 minutes FUNCTION SELECTIONS MICROWAVE/ GRILL/ CONVECTION/ COMBINATION POWER SELECTIONS 10 LEVELS CAVITY VOLUME 1.2 Cu. Ft

* Specifications are subject to change without notice.

1. OUTER DIMENSION

11.DOOR HOOK

When the door is closed, it will automatically lock shut. If door is opened while oven is operating, the magnetron will immediately stop operating.

12.DOOR VIEWING SCREEN

Allows viewing of food. The screen is designed so that light can pass through, but not the microwave.

13.METAL RACK

14.TOP HEATER

Turns on when convection, grill and combi cooking is selected.

15.OVEN LAMP

Automatically turns on during oven operating.

16.SAFETY INTERLOCK SYSTEM

17.CONTROL PANEL

18.TURNTABLE TRAY

Rotates during cooking and ensure even distribution of Microwaves. It can also be used as a cooking utensil.

19.ROLLER GUIDE

This must always be used for cooking together with the turntable tray.

10. COUPLER

This fits over the shaft in the center of the ovens cavity floor. This is to remain in the oven for all cooking.

11. CONVECTION OUTLET & FAN

12. UNDER HEATER

13. OVEN FRONT PLATE

14.DOOR SEAL

Door seal maintains the microwave energy within the oven cavity and prevents microwave leakage.

2. FEATURE DIAGRAM

1. Steady, flat location

This microwave oven should be set on a steady, flat surface. This microwave oven is designed for counter top use only.

2. Leave space behind and side

All air vents should be kept a clearance. If all vents are covered during operation, the oven may overheat and, eventually, cause failure.

3. Away from Radio and TV sets

Poor television reception and radio interference may result if the oven is located close to a TV, Radio, antenna or feeder and so on.

Position the oven as far from them as possible.

4. Away from heating appliances and water taps

Keep the oven away from hot air, steam or splash when choosing a place to position it, or the insulation might be adversely affected and breakdowns occur.

5. Power supply

• Check your local power source. This microwave oven requires a current of approximately 12 amperes, 230V, 50Hz.

• Power supply cord is about 1.2 meters long.

• The voltage used must be the same as specified on this oven. Using a higher voltage may result in a fire or other accident causing oven damage. Using low voltage will cause slow cooking. We are not responsible for damage resulting from use of this oven with a voltage of ampere fuse other than those specified.

• This appliance is supplied with cable of special type, which, if damaged, must be repaired with cable of same type.

• Such a cable can be purchased from DAEWOO and must be installed by a Qualified Person.

6. Examine the oven after unpacking for any damage such as:

A misaligned door, broken door or a dent in cavity. If any of the above are visible, DO NOT INSTALL, and notify dealer immediately.

7. Do not operate the oven if it is colder than room temperature.

(This may occur during delivery in cold weather.) Allow the oven to become room temperature before operating.

This appliance must be earthed. In the event of an electrical short circuit, earthing reduces the risk of the electric shock by providing an escape wire for the electric current. This appliance is equipped with a cord having a earthing wire with a earthing plug. The plug must be plugged into an outlet that is properly installed and earthed.

4. INSTALLATION

EARTHING INSTR UCTIONS

WARNING

Improper use of the earthing plug can result in a risk of electric shock. Consult a qualified electrician of serviceman if the earthing instructions are not completely understood, or if doubt exists as to whether the appliance is properly earthed, and either: If it is necessary to use an extension cord, use only a 3-wire extension cord that has a 3-blade earthing plug, and a 3-slot receptacle that will accept the plug on the appliance. The marked rating of the extension cord should be equal to or greater than the electrical rating of the appliance, or Do not use an extension cord.

5. CONTROL PANEL

DISPLAY WINDOW

1. MICROWAVE - indicator, showing microwaving in

progress.

2. DEFROST- indicator, showing defrosting in progress.

3. GRILL(upper grill heater) - indicator, showing griling in progress.

4. GRILL(lower grill heater) - indicator, showing griling in progress.

5. CONVECTION - indicator, showing convectioning in progress.

6. CHILD LOCK - indicator.

7. % - percentage microwave power level indicator.

BUTTONS

8. language - Press to select the language.

9. clock - Use to set clock.

10. less - Use to remove time from cooking.

11. more - Use to add time to cooking.

12. m/w - Press to select microwave power level.

13. combi - Press to select combi cooking mode.

14. auto defrost - Press to select defrost menu.

15. convection -

Press to select convection temperature.

16. grill - Press to select grill.

17. cake - Press to select cake menu.

18. crusty - Press to select crusty menu.

19. auto cook - Press to select auto cook menu.

20. memory - Use to set favorite cooking mode.

21. start/speedy cook - Press to start a programme,

also for speedy start (each press adds 30 secondsmicrowave cooking time).

22. stop/clear - Press once to stop a programme, and twice to cancel a programme.

23. dial knob - Use to set time, weight and quantity.

6. DISASSEMBLY AND ASSEMBLY

- Cautions to be observed when trouble shooting.

Unlike many other appliances, the microwave oven is high-voltage, high-current equipment. It is completely safe during normal operation. However, carelessness in servicing the oven can result in an electric shock or possible danger from a short circuit. You are asked to observe the following precautions carefully.

1. Always remove the power plug from the outlet before servicing.

2. Use an insulated screwdriver and wear rubber gloves when servicing the high voltage side.

3. Discharge the high voltage capacitor before touching any oven components or wiring. (1) Check the grounding.

Do not operate on a two-wire extension cord. The microwave oven is designed to be used while grounded. It is imperative, therefore, to make sure it is grounded properly before beginning repair work.

(2) Warning about the electric charge in the high voltage capacitor.

For about 30 seconds after the operation has stopped, electric charge remains in the high voltage capacitor. When replacing or checking parts, short between oven chassis and the negative high terminal of the high voltage capacitor by using a properly insulated screwdriver to discharge.

4. When the 15A fuse is blown out due to the operation of the monitor

switch; replace primary interlock switch, secondary interlock switch and interlock monitor switch.

5. After repair or replacement of parts, make sure that the screws are

properly tightened, and all electrical connections are tightened.

6. Do not operate without cabinet.

CAUTION : Service personnel should remove their watches whenever working close to or replacing the magnetron.

WARNING : When servicing the appliance, take care when touching or replacing high potential parts because of

electrical shock or exposing microwave. These parts are as follows - HV Transformer, Magnetron, HV Capacitor, HV Diode.

NOTE: After replacting the door assembly, perform a

check of correct alignment with the hinge and cavity front plate.

1. T o remo ve cabinet

1) Remove four screws on cabinet back.

2) Push the cabinet backward.

2. T o remo ve guide wind assembl y

1) Remove two screws which secure the stopper hinge top.

2) Remove the door assembly from top plate of cavity.

3) Reverse the above for assemby.

3. T o remo ve door parts.

REF NO. PART CODE PART NAME DESCRIPTION Q’TY REMARK

A01 3512603520 HANDLE DOOR ALUMINUM 1 A02 3515307400 SUPPORTER HANDLE KOC-1B4K0S 2 A03 3511605500 DECORATOR DOOR *U STS304 T0.5 1 A04 3511605400 DECORATOR DOOR *T STS304 T0.5 1 A05 3511605700 DECORATOR DOOR *L STS304 T0.5 1 A06 3511605600 DECORATOR DOOR *R STS304 T0.5 1 A07 3512204740 FRAME DOOR PC 1 A08 7001503511 SCREW MACHINE PAN 5X35 MFZN 2 A09 3517004090 BARRIER-SCREEN *O TEMP GLASS T3.2 1 A10 3515204900 STOPPER HINGE *T AS KOC-1B4K0S 1 A11 3516602100 DOOR-PLATE SBHG-1A T0.7 1 A12 3513101200 HOOK POM 1 A13 3515101800 SPRING HOOK PW1 1 A14 3512302300 GASKET DOOR PRT 1

✔ Caution:

In this Service Manual, some parts can be changed for improving, their performance without notice in the parts list. So, if you need the latest parts information, please refer to PPL(Parts Price List) in Service information Center(http://svc.dwe.co.kr)

(1) Remove the gasket door(A14) from door plate. (2) Remove two screws(A08) from door plate. (3) Remove the door handle (A01) and handle supporter (A02) from door plate. (4) Remove the four door decorators (A03~A06) from door frame. (5) Remove the door frame (A07) from door plate. (6) Remove the stopper hinge top(A10) from door plate. (7) Remove the spring(A13) and the hook(A12). (8) Remove the barrier screen outer(A09) from door frame. (9) Reverse the above steps for reassembly.

4. Method to reduce the gap between the door seal and the

oven front surface.

(1) To reduce gap located on part ‘A’.

• Loosen two screws on stopper hinge top, and then push the door to contact the door seal to oven front surface.

• Tighten two screws.

(2) To reduce gap located on part ‘B’.

• Loosen two screws on stopper hinge under, and then push the door to contact the door seal to oven front surface.

• Tighten two screws.

NOTE : A small gap may be acceptable if the microwave leakage does not exceed 4mW/cm2.

5. To remove control panel parts.

REF NO. PART CODE PART NAME DESCRIPTION Q’TY REMARK

B01 3515501720 WINDOW DISPLAY SAN 1 B02 3511605020 DECORATOR C/PANEL STS 304 T0.5 HL 1 B03 3516724140 C-PANEL ABS XR-401 H-2938 1 B04 3516908440 BUTTON FUNCTION-B ABS SG-175 SG-0760D 1 B05 3516908340 BUTTON FUNCTION-A ABS XR-401 H-2938 1 B06 3513406040 KNOB VOLUME ABS SG-175 SG-0760D 1 B07 3511605120 DECORATOR RING ABS 4 B08 3516908540 BUTTON FUNCTION-C ABS SG-175 SG-0760D 4 B09 3514323130 SUB PCB ASS’Y KOC-1B4K 1 B10 7121301011 SCREW TAPPING T2S PAN 3X10 MFZN 7 B11 3514323060 MAIN PCB ASS’Y KOC-1B4K 1 B12 7122401211 SCREW TAPPING T2S TRS 4X12 MFZN 4

(1) Remove four screws(B12) which secure the control panel. (2) Pull out the Main PCB assembly(B11). (3) Remove seven screws(B10) which secure the control panel. (4) Pull out the Sub PCB assembly(B09). (5) Pull out the Knob volume(B06) from the Sub PCB assembly. (6) Pull out six buttons from the control panel. (7) Pull out Decorator ring(B07) and Window display (B01) from the control panel. (8) Pull out the Decorator c-panel (B02) from the control panel. (9) Reverse the above steps for reassembly.

✔ Caution:

CAUTION : Never install the magnetron without the metallic gasket plate which is packed with each magnetron to

prevent microwave leakage. Whenever repair work is carried out on magnetron, check the microwave leakage. It shall not exceed 4mW/cm

for a fully assembled oven with door normally closed.

6. T o remo ve high v oltage capacitor.

1) Remove a screw which secure the grounding ring terminal of the H.V. diode and the capacitor holder.

2) Remove the H.V. diode from the capacitor holder.

3) Reverse the above steps for reassembly.

◆ High voltage circuit wiring

7. T o remo ve magnetr on.

1) Remove a screw which secure the magnetron.

2) Remove the magnetron.

3) Reverse the above steps for reassembly.

Metallic gasket

Magnetron antenna

plate

Cooling fin

Filament terminal

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