Daewoo KOG-867T Service Manual

Service Manual

Microwave Oven & Toaster

Model: KOG-867T

DAEWOO ELECTRONICS CORP.

S/M No. : G867T7S001

http : //svc.dwe.co.kr Dec. 2003

✔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.

(e) 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

SAFETY AND PRECAUTIONS........................................................................................................................................3

FOR SAFE OPERATION...........................................................................................................................................3

FOR SAFE SERVICE PROCEDURES .....................................................................................................................3

SPECIFICATIONS ................................................................................................................. ...........................................4

EXTERNAL VIEW.............................................................................................................................................................5

OUTER DIMENSION.................................................................................................................................................5

FEATURE DIAGRAM.................................................................................................................................................6

CONTROL PANEL.................................................................................................................. ...................................7

INSTALLATION................................................................................................................................................................8

OPERATION PROCEDURE(MICROWAVE OVEN)........................................................................................................9

IMPORTANT ...................................................................................................................................................................10

OPERATION PROCEDURE(TOASTER).......................................................................................................................11

DISASSEMBLY AND ASSMBLY...................................................................................................................................12

INTERLOCK MECHANISM AND ADJUSTMENT.........................................................................................................20

TROUBLE SHOOTING GUIDE......................................................................................................................................21

MESUREMENT AND TEST............................................................................................................................................26

MEASUREMENT OF THE MICROWAVE POWER OUTPUT................................................................................26

MICROWAVE RADIATION TEST ...........................................................................................................................27

COMPONENT TEST PROCEDURE.......................................................................................................................28

WIRING DIAGRAM.........................................................................................................................................................29

PRINTED CIRCUIT BOARD...........................................................................................................................................30

CIRCUIT CHECK PROCEDURE.............................................................................................................................30

PCB CIRCUIT DIAGRAM ........................................................................................................................................33

P.C.B. LOCATION NO.............................................................................................................................................34

EXPLODED VIEW AND PARTS LIST...........................................................................................................................35

DOOR ASSEMBLY..................................................................................................................................................35

CONTROL PANEL ASSEMBLY..............................................................................................................................35

TOTAL ASSEMBLY.................................................................................................................................................35

SAFETY ANDPRECA UTIONS

CAUTION : This Device is to be Serviced Only by Properly Qualified Service Personnel. Consult the Service

Manual for Proper Service Procedures to Assure Continued Safety Operation and for Precautions to be Taken to Avoid Possible Exposure to Excessive Microwave Energy.

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 have excessive emission level 5mW/cm

, the service person should: (a) inform the manufacturer, importer or assembler, (b) repair the unit at no cost to the owner, (c) attempt to ascertain the cause of the excessive leakage, (d) 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.

CAUTION

MICROWAVE RADIATION

PERSONNEL SHOULD NOT BE EXPOSED TO THE MICROWAVE ENERGY WHICH MAY RADIATE FROM THE MAGNETRON OR OTHER MICROWAVE GENERATING DEVICE IF IT IS IMPROPERLY USED OR CONNECTED. ALL INPUT AND OUTPUT MICROWAVE CONNECTIONS. WAVEGUIDES FLANGES AND GASKETS MUST BE SECURED. NEVER OPERATE THE DEVICE WITHOUT A MICROWAVE ENERGY ABSORBING LOAD ATTACHED. NEVER LOOK INTO AN OPEN WAVEGUIDE OR ANTENNA WHILE THE DEVICE IS ENERGIZED.

WARNING: This appliance must be earthed.

SPECIFICATIONS

IMPORTANT

The wires in this mains lead are colored in accordance with the following code.

Green-and-yellow : Earth Blue : Neutral

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

* Specifications are subject to change without notice.

POWER SUPPLY 230V AC 50 Hz SINGLE PHASE WITH EARTHING

POWER CONSUMPTION 1350 W OUTPUT POWER 900 W

MICROWAVE OVEN

FREQUENCY 2450 MHz TIMER 59 min. 90 sec. POWER LEVELS 10 LEVELS CAVITY DIMENSIONS 320 x 244 x 338 mm (12.6 x 9.6 x 13.3 inch)

CAVITY VOLUME 0.9 Cu.ft TOASTER MICROWAVE + TOASTER

POWER CONSUMPTION

900 W

2200 W OUTSIDE DIMENSIONS (W x H x D) 583 x 301 x 421 mm (22.9 x 11.8 x 16.5 inch) NET WEIGHT APPROX. 15.7 KG (34.3 lbs)

EXTERNAL VIEW

1. OUTER DIMENSION

M/W TOAST DEF. TIMER

TOAST

BREAD BAGEL

START

AUTO

DEFROST

STOP CLEAR

M / W

1.Beverage

5.Dinner Plate

4.Fresh

Vegetable

3.Frozen Pizza

2.Baked Potato

KITCHEN

TIMER

MEMORY

AUTO

COOK

10 MIN 1 HOUR

1 MIN 10 MIN

10 SEC 1 MIN

MORE LESS

START

SPEEDY COOK

STOP

CLEAR

CLOCK

1. DOOR LATCH

When the door is closed it will automatically shut off. If the door is opened while the oven is operating, the

magnetron will automatically shut off.

2. DOOR SEAL

The door seal maintains the microwave within the oven cavity and prevents microwave leakage.

3. OVEN CAVITY

4. SPATTER SHIELD

Protects the microwave outlet from splashes of cooking foods.

5. SAFETY INTERLOCK SYSTEM

Prevents the oven from operating while the door is opened.

6. DOOR RELEASE BUTTON

Pushing this button stops oven operation and opens the door.

7. GLASS COOKING TRAY

Made of special heat resistant glass. The tray must always be in proper position before operating. Do not cook food directly on the tray.

8. ROLLER GUIDE

Supports the glass cooking tray.

9. DOOR SCREEN

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

10. TOASTER DRAWER

11. TOASTER OPENING HANDLE

12. CRUMB TRAY(REFER. PAGE10)

2. FEATURE DIAGRAM

MICROWAVE OVEN TOASTER

23450

9876w

M/W TOAST DEF. TIMER

TOAST

BREAD BAGEL

START

AUTO

DEFROST

STOP CLEAR

M / W

1.Beverage

5.Dinner Plate

4.Fresh

Vegetable

3.Frozen Pizza

2.Baked Potato

KITCHEN

TIMER

MEMORY

AUTO COOK

10 MIN 1 HOUR

1 MIN 10 MIN

10 SEC 1 MIN

MORE LESS

START

SPEEDY COOK

STOP

CLEAR

CLOCK

Time set pad - Used to set the cooking time and the present time.

Display - Cooking time, power level, indicators and present time are displayed.

Toast Bread - Used to reheat bread.

Toast Bagel- Used to reheat bagel.

Toast Stop/Clear - Used to stop the toast operation or to clear the toast setting.

Used to transfer toaster mode to microwave mode.

Toast Start - Used to toast start.

Memory - Used to set favorite cooking mode.

Auto Cook - Used to cook or reheat.

More-Used to add time to cooking.

Less-Used to remove time from cooking.

Auto Defrost - Used to defrost foods.(for weight and time)

M/W - Used to select microwave power level.

Kitchen Timer - Used as a minute timer, to delay the start of cooking, or to set a holding time after cooking.

Clock - Used to set clock.

Stop/Clear - Used to stop the Microwave operation or to delete the cooking data.

Used to transfer Microwave mode to toaster mode.

Start/Speedy Cook - Used to start the oven and also used to set a reheat time.

M/W TOAST DEF. TIMER

TOAST

BREAD BAGEL

START

AUTO

DEFROST

STOP

CLEAR

M / W

1.Beverage

5.Dinner Plate

4.Fresh

Vegetable

3.Frozen Pizza

2.Baked Potato

KITCHEN

TIMER

MEMORY

AUTO COOK

10 MIN

1 HOUR

1 MIN

10 MIN

10 SEC

1 MIN

MORE LESS

START

SPEEDY COOK

STOP

CLEAR

CLOCK

3. CONTROL PANEL

INSTALLATION

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 oven failure. Position the oven as far from them as passible.

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.

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 and toaster requires a current of approximately 10 amperes, 230Volts, 50Hz grounded outlet. Power supply cord is about 1.0 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 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.

W ARNING

Improper use of the earthing plug can result in a risk of electric shock. Consult a qualified electrician or 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.

EARTHING INSTRUCTIONS

once P-HI 100%

twice P-90 90% 3 times P-80 80% 4 times P-70 70% 5 times P-60 60% 6 times P-50 50% 7 times P-40 40% 8 times P-30 30% 9 times P-20 20%

10 times P-10 10% 11 times P-00 0%

Touch MICROWAVE pad Power level (Display) Approximate Percentage of Power

OPERATION PR OCEDURE(MICROW AVE O VEN)

The oven light is on only when the microwave oven is operating.

The oven door can be opened at any time during operation by touching the door release button on the control panel. The oven will automatically shut off.

Each time a pad is touched, a BEEP sounds to acknowledge the touch.

The oven automatically cooks on full power unless set to a lower power level.

The display will show

: 0 when the oven is plugged

in.

Time clock returns to the present time when the cooking time ends.

When the Microwave STOP/CLEAR pad is touched during the oven operation, the oven stops cooking and all information retained. To erase all information(except the present time), touch the STOP/CLEAR pad once more. If the oven door is opened during the oven operation, all information is retained.

If the Microwave START pad is touched and the oven does not operate, check the area between the door and door seal for obstructions and make sure the door is closed securely. The oven will not start cooking until the door is completely closed or the program has been reset.

This section includes useful information about Microwave oven operation.

1. Plug power supply cord into a standard 3-pronged 15Amp, 230V AC 50Hz poweroutput.

2. After placing the food in a suitable container, open the oven door and put it on the glass tray. The glass tray and roller guide must always be in place during cooking.

3. Shut the Microwave oven door. Make sure that it is firmly closed.

1 2

3 4

5 6

Make sure the oven is properly installed and plugged into the electrical outlet.

W ATT AGE OUTPUT CHART

The power-level is set by pressing the MICROWAVE pad. The chart shows the display, the power level and the

percentage of power.

IMPORTANT

Before using the toaster for the first time, operate the toaster without bread in order to burn off residues on the heating elements. You will notice an odor that is characteristics of new heating elements. This is normal and will soon disappear.

CLEANING THE T OASTER

Always unplug the Microwave oven & Toaster and allow the toaster to cool completely before cleaning.

Toaster drawer:

Wipe surface with a soft, clean, damp cloth. Never use abrasive cleaners, as they may scratch the surface. Do not use fork or other sharp, metal object to clean inside of the Toaster drawer, or to remove toast, as it may damage heating elements.

Crumb Tray :

After allowing the toaster to cool down and closing the door, gently slide out the crumb tray. Brush crumbs off the tray and, if necessary, wipe it with a clean, damp cloth. Always dry the tray thoroughly. When sliding the crumb tray into place, be sure you feel and hear it snap into position.

COOKING TIPS

W ARNING!

Never place any object in the toaster for any reason!

DO NOT toast pastries with runny fillings or frosting. DO NOT toast torn slices of bread or broken pastries. DO NOT place buttered bread, wrapped food, or frozen pastries in the toaster. DO NOT use this toaster to toast or warm small-size bread slices. These include melba size breads, slices of

mini-baguettes, breadsticks, etc.

DO NOT toast oversized bagel. Because thick bagels surface may become closer to the heater, this may cause

overdone of surface and smoke.

NOTE : Different types of bread and their moisture levels may require different darkness settings. For

example, dry bread will brown more rapidly than moist bread and so will be toasted to your taste at a lighter setting.

NOTE : 2 pieces of bread or bagel should be cooked with this toaster.

OPERATION PR OCEDURE(T O ASTER)

The toaster drawer can be opened at any time during operation by pulling out the toaster handle on the toaster drawer. The toaster will automatically shut off.

Touch the bread or bagel pad of toast menu and the degree of darkness will be displayed.

Each time a pad is touched, a BEEP sounds to acknowledge the touch.

Touch toaster start pad and then the toast indicator linght is on and the best cooking time is displayed according to the condition of the toaster (not in the case of time toasting) and toast cooking starts. During the toast cooking, hot smoke or air may goes out from the gap of the toaster drawer.

When the toast STOP/CLEAR pad is touched during the oven operation, the toaster stops cooking and all information retained. To erase all information(except the present time), touch the STOP/CLEAR pad once more. If the toaster drawer is opened during the toaster operation, all information is retained.

If the toast START pad is touched and the toaster does not operate, check the toaster drawer is closed securely. The toaster will not start cooking until the toaster drawer is completely closed or the program has been reset.

This section includes useful information about toaster operation.

1. Plug power supply cord into a standard 3-pronged 15Amp, 230V AC 50Hz poweroutput.

2. Put 2 pieces of toast bread or bagel between the toaster guides (wire rack) of the toaster drawer.

3. Shut the toaster drawer. Make sure that it is firmly closed.

1 2

3 4

NOTE :

When the toaster drawer is opened after toast cooking, hot smoke or air will go out and the toaster guides (wire rack) are very hot. Take out food carefully not to touch hot surfaces of the toaster or hot air.

NOTE :

When the toaster is operated several times in series and is overheated, the safety thermal switch works and the heating elements stop operating. So, though the toaster seems to operate normally, it does not cook toast. Open the toaster drawer and cool it for 5~6 min. After then the toaster can cook toast normally.

NOTE :

When you start toast cooking (br-1~br-3 and bg-1~bg-3) within 1 min. in series after toast cooking, the toaster starts cooking with cooling time automatically added to the cooking time.

NOTE :

When you start toast cooking, the best cooking time is displayed according to the condition of the toaster. (br-1~br-3: 1 min. 20 sec.~2 min. 40 sec/ bg-1~bg-3: 1min. 20 sec.~2 min. 45 sec.)

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 earthed. 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 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, HV Fuse.

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