DAEWOO KOG-372G0S, KOG-372H0S, KOG-392G0S, KOG-392H0S Service Manual

S/M No. : G372G0S001

Service Manual

Microwave Oven

Model: KOG-372G0S

KOG-372H0S

KOG-392G0S

KOG-392H0S

DAEWOO ELECTRONICS CO., LTD.

PRECAUTIONS TO BE OBSERVED BEFORE AND DURING SERVICING TO AVOID POSSIBLE EXPOSURE TO EXCESSIVE MICROWAVE ENERGY

(a) Do not operate or allow the oven to be operated w ith the door open.

(b)M ake the following safety checks on all ovens to be serviced before activating the m agnetron or other microwave source, and make repairs as necessary: (1) Interlock operation, (2) Proper door closing, (3) Seal and sealing surfaces (arcing, wear, and other damage), (4) Dam age to or loosening of hinges and latches, (5) Evidence of dropping or abuse.

(c)Before turning on power to the m icrow ave oven for any service test or inspection within the microwave generating compartments, check the magnetron, wave guide or transm ission line, and cavity for proper alignment, integrity, and connections.

(d)Any defective or misadjusted components in the interlock, m onitor, door seal, and microwave generation and transm ission systems shall be repaired, replaced, or adjusted by procedures described in this manual before the oven is released to the owner.

(e)A m icrowave leakage check to verify com pliance with the Federal performance standard should be perform ed on each oven prior to release to the owner.

SAFETY AND PRECAUTIONS ...........................................................................................................	2
1. FOR SAFE OPERATION ..............................................................................................................	2
2. FOR SAFE SERVICE PROCEDURES .........................................................................................	2
SPECIFICATIONS ...............................................................................................................................	3
EXTERNAL VIEW................................................................................................................................	4
1. OUTER DIMENSION.....................................................................................................................	4
2. FEATURE DIAGRAM ....................................................................................................................	5
3. CONTROL PANEL ........................................................................................................................	6
INSTALLATION ..................................................................................................................................	8
OPERATIONS AND FUNCTIONS.......................................................................................................	9
DISASSEMBLY AND ASSEMBLY......................................................................................................	10
INTERLOCK MECHANISM AND ADJUSTMENT...............................................................................	19
TROUBLE SHOOTING GUIDE ...........................................................................................................	20
MEASUREMENT AND TEST ..............................................................................................................	24
1. MEASUREMENT OF THE MICROWAVE POWER OUTPUT ......................................................	24
2. MICROWAVE RADIATION TEST .................................................................................................	25
3. COMPONENT TEST PROCEDURE .............................................................................................	26
WIRING DIAGRAM..............................................................................................................................	27
PRINTED CIRCUIT BOARD................................................................................................................	28
1. CIRCUIT CHECK PROCEDURE ..................................................................................................	28
2. PCB CIRCUIT DIAGRAM..............................................................................................................	31
3. P.C.B. LOCATION NO. .................................................................................................................	32
EXPLODED VIEW AND PARTS LIST.................................................................................................	34
1. DOOR ASSEMBLY .......................................................................................................................	34
2. CONTROL PANEL ASSEMBLY....................................................................................................	34
3. TOTAL ASSEMBLY.......................................................................................................................	34

SAFETY AND PRECAUTIONS

1. FOR SAFE OPERATION

D am age that allow s the m icrow ave energy (that cooks or heats the food) to escape will result in poor cooking and m ay cause serious bodily injury to the operator.

IF AN Y O F TH E FOLLO W IN G CO N D ITIO N S EXIST, O PERATO R MU S T N O T US E TH E APPLIAN C E . (O nly a trained service personnel should m ake repairs.)

1)A broken door hinge.

2)A broken door view ing 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.

N o grease, soil or spatter should be allow ed to build up on these surfaces or inside the oven.

D O N O T ATTEM PT TO O PER AT E T HIS APPLIAN CE W IT H TH E D O O R O PEN . The m icrow ave oven has concealed sw itches to m ake sure the power is turned off w hen the door is opened. D o not attem pt to defeat them .

D O N O T ATTEM PT TO SERVIC E TH IS APPLIAN C E U N TIL YO U H AVE R EA D T HIS SERVIC E M ANU AL.

2. FOR SAFE SERVICE PROCEDURES

1)	If the oven is operative prior to servicing, a m icrowave em ission check should be perform ed prior to servicing the oven.
2)	If any certified oven unit is found to servicing, a m icrowave em ission check should be perform ed prior to servicing the oven.
	(a) inform the m anufacturer, im porter or assem bler,
	(b) repair the unit at no cost to the ow ner,
	(c) attem pt to ascertain the cause of the excessive leakage,
	(d) tell the ow ner of the unit not to use the unit until the oven has been brought into com pliance.
3)	If the oven operates with the door open, the service person should tell the user not to operate the oven and contact the
	m anufacturer im m ediately.

IMPORTANT

The w ire in this m ains lead coloured in accordance w ith the follow ing code.

G reen-and-yellow : Earth

Blue	: N eutral
Brow n	: Live

As the colours of the w ires in the m anins lead of this appliance m ay not correspond w ith the coloured m arkings identifying the term inals in your plug, proceed as follow s.

The w ire w hich is coloured green-and-yellow m ust be connected to the term ianl in the plug w hich is m arked with the letter ‘E’, earth sym bol or coloured green-and-yellow.

The w ire w hich is coloured blue m ust be connected to the term inal which is m arked w ith the letter ‘N ’ or coloured black.

The w ire w hich is coloured brow n m ust be connected to the term inal w hich is m arked w ith the letter ‘L’ or coloured red.

NOTE

This oven is designed for counter-top use only.

SPECIFICATIONS

	M O D EL		K O G -372G /H	KO G -392G /H
	PO W E R SUP PLY		230V -50Hz, SING LE PH AS E W ITH E ARTH IN G
		M IC RO W AVE	1200W	1350W
	PO W E R
		G R ILL	1050W	1050W
	CO N SU M PTIO N
		CO M BIN ATIO N	2200W	2350W
	M IC RO W AVE E NE RG Y O U TP UT		800W	900W
	M IC RO W AVE FRE Q UE NC Y		2450M Hz
	O UT S ID E DIM EN SIO N S (W X H X D)		465 x 279 x 360m m (18.3 x 11.0 x 14.2 in.)	495 x 294 x 388m m (19.5 x 11.6 x 15.3 in.)
	CAV IT Y DIM E NS IO N S (W X H X D)		290 x 220 x 306 m m (11.4 x 8.7 x 12.0 in.)	320 x 244 x 338m m (12.6 x 9.6 x 13.3 in.)
	NE T W E IG HT		A PP RO X . 13.7K g (30.2lbs.)	AP PR O X. 15.8Kg (34.9lbs.)
	TIM ER		59 m in. 90 sec.
	FU NCTIO N S ELE CTIO N S		M IC RO W AV E
	PO W E R SE LE CT IO N S		10 LE VE LS
	CAV IT Y VO LUM E		0.7 C u.Ft.	0.9 Cu.Ft.

SPECIFICATIONS ARE SUBJECT TO CHANGE W ITHOUT NOTICE.

EXTERNAL VIEW

1. OUTER DIMENSION

EXTERNAL VIEW

2. FEATURE DIAGRAM

1. DOOR SEAL - Door seal maintains the microwave energy within the oven cavity and prevents microwave leakage.

2. REFLECTOR (Insulator Heater)

3.HEATING ELEMENT

4.OVEN CAVITY

5.SEFETY INTERLOCK SYSTEM

6.CONTROL PANEL

7.METAL RACK

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

9.ROLLER GUIDE - This must always be used for cooking together with the glass cooking tray.

10.GLASS COOKING TRAY - Made of special heat resistant glass. Food in a proper receptacle is placed on this tray for cooking.

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

12.DOOR HOOK - When the door is closed, it will automatically shut off. If the door is opened while the oven is operating, the magnetron will immediately stop operating.

EXTERNAL VIEW

3.CONTROL PANEL

(1) KOG-372G0S/392G0S

2

	4
	3
5	6
	7
8	9
10	11
12	13
	1
14	15

1.TIME SET PAD - Used to set the cooking time and the present time.

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

3.ONE TOUCH - Used to cook or reheat specific quantities of food.

4.AUTO COOK - Used to cook or reheat.

5.MORE - Used to add time to cooking.

6.LESS - Used to remove time from cooking.

7.AUTO DEFROST - Used to defrost foods.(for weight)

8.COMBI - Used to cook COMBI.

9. GRILL - Used to cook GRILL

10.POWER - Used to set power level.

11.DEFROST - Used to defrost foods. (for time)

12.KITCHEN TIMER - Used as a minute timer, to delay the start of cooking, or to set a holding time after cooking.

13.CLOCK - Used to set clock.

14.STOP/CLEAR - Used to stop the oven operation or to delete the cooking data.

15.START/SPEEDY COOK - Used to start the oven and also used to set a reheat time.

EXTERNAL VIEW

(2) KOG-372H0S/392H0S

2

	3
4	5

	6
7	8
9	10
11	12
	1
13	14

1.TIME SET PAD - Used to set the cooking time and the present time.

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

3.ONE TOUCH- Used to cook or reheat specific quantities of food.

4.MORE - Used to add time to cooking.

5.LESS - Used to remove time form cooking.

6.AUTO DEFROST - Used to defrost foods, (for weight)

7.COMBI - Used to cook COMBI.

8. GRILL - Used to cook GRILL.

9.POWER - Used to set power level.

10.DEFROST - Used to defrost foods. (for time)

11.KITCHEN TIMER - Used as a minute timer, to delay the start of cooking, or to set a holding time after cooking.

12.CLOCK - Used to set clock.

13.STOP/CLEAR - Used to stop the oven operation or to delete the cooking data.

14.START/SPEEDY COOK - Used to start the oven and also used to set a reheat time.

INSTALLATION

1. Steady, flat location

This m icrow ave oven should be set on a steady, flat surface. This m icrow ave 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 m ay overheat and, eventually, cause failure.

3. Away from radio and TV sets

Poor television reception and radio interference m ay 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 aw ay from hot air, steam or splash w hen choosing a place to position it, or the insulation m ight be adversely affected and breakdow ns occur.

5. Power supply

C heck your local pow er source.

This m icrow ave oven requires a current of approxim ately 11 am peres, 230 Volts, 50 H z.

Pow er supply cord is about 0.8 m eters long.

The voltage used m ust be the sam e as specified on this oven. U sing a higher voltage m ay result in a fire or other accident

causing oven dam age. U sing low voltage will cause slow cooking. W e are not responsible for dam age resulting from use of this oven w ith a voltage of am pere fuse other than those specified.

This appliance is supplied w ith cable of special type, w hich, if dam aged, m ust be repaired w ith cable of sam e type. Such a cable can be purchased from DAEW O O and m ust be installed by a Q ualified Person.

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

A m isaligned door, broken door or a dent in cavity.

If any of the above are visible, D O N O T IN STALL, and notify dealer im m ediately.

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

(This m ay occur during delivery in cold w eather.) Allow the oven to becom e room tem perature before operating.

EARTHING INSTRUCTIONS

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

WARNING

Im proper use of the earthing plug can result in a risk of electric shock. C onsult a qualified electrician or servicem an if the earthing instructions are not com pletely understood, or if doubt exists as to w hether 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 m arked rating of the extension cord should be equal to or greater than the electrical rating of the appliance, or D o not use an extension cord.

OPERATIONS AND FUNCTIONS

1. Connect the main lead to an electrical outlet.

2. After placing the food in a suitable container, open the oven door and put it on the glass tray. The glass tray must always

	be in place during cooking.
3	. Close the door securely.
4	. W hen the oven door is opened, the light turns off.
5	. 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. To restart the oven, close the door and then touch START.
6	. Each time a pad is touched, a BEEP will sound to acknowledge the touch.
7	. The oven automatically cook on full power unless set to a lower power level.
8	. The display will show :0 when the oven is plugged in.
9	. Time clock returns to the present tim e when the cooking time ends.

10. W hen the 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.

11. If the START pad is touched and the oven does not operate, check the area betw een the door and door is closed

securely. The oven will not start cooking under the door is completely closed or the program has been reset. 12. When using the GRILL or COMBI mode ;

Do not open the door so often, the temperature inside the oven decrease and the cooking may not be completed in setting time.

Never touch the oven window and metal interior of the oven when taking food in and out, because the temperature inside

the oven and door is very high.

When using these modes, be careful as the tray will be hot to touch, use oven gloves or pot holders while handling tray.

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

W attage output chart

The power level is set by pressing the Power pad. The chart shows the display, the power level and the percentage of power.

Touch Power pad.		Power level (Display)	Approximate Percentage of Power
O nce		P -H I	100 %
Tw ice		P -90	90 %
3	tim es	P -80	80 %
4	tim es	P -70	70 %
5	tim es	P -60	60 %
6	tim es	P -50	50 %
7	tim es	P -40	40 %
8	tim es	P -30	30 %
9	tim es	P -20	20 %
10 tim es		P -10	10 %
11 tim es		P -00	0 %

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 safety 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 ware rubber gloves when servicing the high voltage side.

3.Discharge the high voltage capacitor before touching any oven components or wiring.

(1) Check the earthed.

Do not operate on a two-wire extension cord.

The microwave oven is designed to be used with earthed.

It is imperative, therefore, to makes sure it is earthed properly before beginning repair work.

(2) Warning about the electric charge in the high voltage capacitor. For about 30 seconds after the operation stopped and 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 rem ove their w atches w henever working close to or replacing the m agnetron.

WARNING

W hen servicing the appliance, need a care of touching or replacing high potential parts because of electrical shock or exposing m icrow ave. These parts are as follow s - H V Transform er, M agnetron, H V C apacitor, HV D iode. H V Fuse.

DISASSEMBLY AND ASSEMBLY

1. To remove cabinet

1)Remove three screws on cabinet back.

2)Push the cabinet backward.

2. To remove door assem bly

1)Remove a screw which secure the stopper hinge top.

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

3)Reverse the above for reassembly.

NOTE

After replacing the door assem bly, perform a check of correct alignm ent with the hinge and cavity front plate.