Sears 721.69252990, 721.69259990 Basic Field Manual

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Page 1

DIVISION 20

BASIC FIELD MANUAL

FOR

MICROWAVE OVEN

MODEL 721.69252990

721.69259990

June, 1999

MODEL 721.69252990

721.69259990

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-1-

CAUTION

WARNING TO SERVICE TECHNICIANS

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 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 as 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 microwave 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 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.

• Proper operation of the microwave ovens requires that the magnetron be assembled to the wave guide and

cavity. Never operate the magnetron unless it is properly installed.

• Be sure that the magnetron gasket is properly installed around the dome of the tube whenever installing the

magnetron.

• Routine service safety procedures should be exercised at all times.

• Untrained personnel should not attempt service without a thorough review of the test procedures and safety

information contained in this manual.

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MODEL 721.69252990

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FOREWORD

Read this Manual carefully. Failure to adhere to or observe the information in this Manual may result in exposing yourself to the Microwave Energy normally contained within the oven cavity.

MODEL 721.69252990

721.69259990

MECHANICAL SERVICE INFORMATION

TABLE OF CONTENTS

1. Adjustment Procedures . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3

2. Precautions on Installation . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5

3. General Precautions in Use . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5

4. Trial Operation . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5

5. Specifications . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 6

6. Overall Circuit Diagram . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 7-8

7. Operating Procedures . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 9-11

8. Procedure for Measuring Microwave Energy Leakage . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 12-13

9. Disassembly Instructions . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 14-18

10. Interlock Continuity Test . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 19

11. Test and Checkout Procedures, and Troubleshooting

A. Test Procedures . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 20-22

B. Checkout Procedures . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 23-25

C. Troubleshooting . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 26-30

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1. ADJUSTMENT PROCEDURES

To avoid possible exposure to microwave energy

leakage, adjust the door latches and interlock switches, using the following procedure.

ONLY AUTHORIZED SERVICE PERSONNEL SHOULD MAKE THIS ADJUSTMENT.

The Interlock Monitor and Primary Interlock Switch acts as the final safety switch protecting the user from microwave energy. The terminals between “COM” and “NC” of the Interlock Monitor must close when the door is opened. After adjusting the Interlock Monitor Switch, make sure that it is correctly connected. See Figures 1-a and 1-b throughout this procedure.

CHECK THE DOOR LATCH AND SWITCH CLOSINGS.

NOTE: The outer cover of the microwave oven is

removed.

(1) Set the microwave oven on its side so that you can

see the latch board and the switches, as shown in Figure 1-a.

(2) Close the door tightly and check gaps A and B to be

sure they are no more than 1/64” (0.5 mm). See Figure 1-b for close-up view of gaps A and B (door

latches). If all gaps are less than 1/64” (0.5 mm), adjustment of the latch board may not be necessary. Go to Steps 5 and 6 to check the sequence of the switches.

NOTE: To correct sequence of the Primary Interlock

Switch, Secondary Interlock Switch and the Interlock Monitor Switch is very important.

If any gap is larger than 1/64” (0.5 mm), you will need to adjust the latch board-U, L. Go to step 3 and follow all steps in order.

ADJUST THE LATCH AND SWITCH CLOSINGS

(3) Loosen the two screws holding the plastic latch board

as shown.

(4) With the oven door closed tightly, move the latch

board upward toward the top of the oven and/or away from the door latch until the gaps are less than 1/64” (0.5 mm).

Hold the latch board tightly in this position until you check the sequence of the switches in steps 5 and 6.

TEST THE LATCH AND SWITCH SEQUENCE

(5) Open the oven door slowly. Watch the door latch, the

Primary Switch. Release Rod and Lever on the switches to make sure they are zero to the body of the switches in the following sequence:

- Primary Interlock Switch

- Secondary Interlock Switch

- Interlock Monitor Switch

Adjust the latch board until the switches operate in this sequence. See Steps 3 and 4.

(6) Close the oven door slowly and be sure it is tightly

closed. Watch the three switches to make sure they are zero to the body of the switches in the following sequence:

- Interlock Monitor Switch

- Primary Interlock Switch

- Secondary Interlock Switch

NOTE: The Interlock Monitor Switch is an added safety

check on the Primary and Secondary Interlock Switches. If the Primary and Secondary Interlock Switches allow the oven to operate with the door open, the Monitor Switch will blow the fuse.

(7) When you achieve the proper sequence of switches

in Steps 5 and 6, tighten the latch board screws at that point.

TEST THE MICROWAVE ENERGY LEAKAGE

(8) Using a survey meter, make sure the microwave

energy is below 5 mW/cm.sq.

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LATCH BOARD

INTERLOCK MONITOR SWITCH

PRIMARY INTERLOCK SWITCH

SECONDARY INTERLOCK SWITCH

SCREW

LATCH

LATCH BOARD

0-1/64"

DOOR LATCH

RELEASE LEVER

Figure 1-a

Figure 1-b

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2. PRECAUTIONS ON INSTALLATION

(Figure 2)

A. Plug the power supply cord into a 120 V AC,

60 Hz, single-phase power source with a capacity of

at least 20 amperes.

B. Since the unit weights about 38 lbs, be sure to place

it on a sturdy and flat surface.

C. Avoid placing the unit in a location where there is

direct heat or splashing water.

D. Place the unit as far away as possible from TV, radio,

etc. to prevent interference.

CAUTION

3. GENERAL PRECAUTIONS IN USE

A. Never operate the unit when it is empty. Operating

the oven with no load may shorten the life of the

magnetron. Whenever cooking dry foods (dried fish,

bread, etc.) or a small amount of food, be sure

to put a glass of water into the cooking

compartment. The turntable tray may become hot

after operating, be careful when touching it.

B. Aluminum foil should be avoided because it will

disrupt cooking and may cause arcing. However,

small pieces may be used to cover some parts of

food to slow the cooking. Any aluminum foil used

should never be closer than 2.5 cm to any side wall of

the oven.

4. TRIAL OPERATION

After installation, the following sequences and results should be checked carefully. A. Put a container filled with water (about 1 liter) into the

oven, and close the door tightly.

B. Touch the STOP/CLEAR and the COOK TIME keys. C. Set cooking time for 10 minutes by touching “1”

and then “0” three times. “1000” appears in the display window.

D. Touch the START key.

Make sure the cavity light comes on. The unit will begin cooking and the display window will show the time counting down by seconds.

E. After about 5 minutes, make sure the primary

interlock switch, the secondary interlock switch and the interlock monitor and oven lamp switch operate properly by opening and closing the door several times. Touch the START key each time the door is closed.

F. Continue operating the unit. Two short and a long

beep sound signal is heard when the time is up.

The unit will shut off automatically. G. Confirm the water is hot. H. Finally, measure the output power according to

“POWER OUTPUT MEASUREMENT” on page 13.

5. FEATURES AND SPECIFICATIONS

A. The safety systems incorporated in this model are:

(1) Primary interlock switch

(2) Secondary interlock switch

(3) Interlock monitor switch

(4) Choke system

(5) Magnetron thermostat

(6) Oven cavity thermostat

(Note: This thermostat located on the oven cavity will open and stop the unit from operation only if a high temperature is reached, such as, a fire created by overcooking food.)

B. Any one of 10 power output levels ranging 100W to

1000W can be selected by the touch control and

electronic computer system. C. Cooking time can be displayed on the digital readout. D. Three different cooking stages can be set. The oven

remembers three cooking stages and changes from

one cooking stage to another. This is made possible

with the memory function of the microprocessor.

This unit is equipped with a 3-prong plug for your safety. If the wall outlet is a grounded 3-hole type, the unit will be grounded automatically.

Three-Pronged(Grounding) Plug

Figure 2

-5-

Properly Polarized and Grounded Outlet

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SPECIFICATIONS

Rated Power Consumption 1530W maximum Output

1100W maximum (*IEC 705 Rating standard)

Adjustable 100W through 1100W, 11 steps Frequency 2,450 MHz 50 MHz Power Supply 120V 12V AC, 60Hz Rated Current 13.3 Amp. Magnetron Cooling Forced Air Cooling Microwave Stirring Turntable Rectification Rectification Voltage Doubler Half-Wave Door Sealing Choke System Safety Devices Thermostat:

Open at 90˚C 5˚C

Open at 75˚C 5˚C Fuse(20A) Primary Interlock Switch Secondary Interlock Switch Interlock Monitor

Magnetron 2M246 High Voltage Capacitor Capacitor: 1.00 F, 2.1KV Ac High Voltage Diode 350mA, 9.0KV Cavity Lamp 125V, 20W Timer Digital, up to 99 mm. 99 sec. (in each cooking stage) Tray Tempered Safety Glass Overall Dimensions 20

/8”(W) x 123/8”(H) x 151/2”(D)

Oven Cavity Size 13

/4”(W) x 93/8”(H) x 143/8”(D)

Effective Capacity of Oven Cavity 1.1 Cu.ft. Accessories Use and Care Manual ,Turntable,

Rotating Ring Assembly.

SWITCH CHART

NOTE: Use the above switch chart with circuit diagram on page 7.

PRIMARY SECONDARY INTERLOCK INTERLOCK INTERLOCK MONITOR SWITCH SWITCH SWITCH

COM COM COM

NO NO NC

-6-

SWITCH MODE

CONDITIONS

DOOR OPEN

DOOR CLOSED

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6. OVERALL CIRCUIT DIAGRAM A. SCHEMATIC DIAGRAM

-7-

IMPORTANT SAFETY NOTE: THE SHADED AREAS ON THIS SCHEMATIC DIAGRAM INCORPORATE SPECIAL FEATURES

IMPORTANT FOR PROTECTION FROM MICROWAVE RADIATION, FIRE, ELECTRICAL SHOCK, AND

HAZARDS. WHEN SERVICING IT IS ESSENTIAL THAT ONLY MANUFACTURER’S SPECIFIED PARTS

BE USED FOR THE CRITICAL COMPONENTS IN THE SHADED AREAS OF THE SCHEMATIC DIAGRAM.

NOTICE: SINCE THIS IS BASIC SCHEMATIC DIAGRAM, THE VALUES OF COMPONENTS AND

SOME PARTIAL CONNECTIONS ARE SUBJECT TO CHANGE FOR IMPROVEMENT.

1 2 3 4 5 6 7 8

TTM

12345678

SYMBOL

NOTE:

1. DOOR IS OPEN.

2.RS: SENSING ELEMENT RC: COMPENSATING ELEMENT

3. WIRE COLOR.

COLOR WHITE BLACK

YELLOW PINK

BLUE

GREEN BROWN

YL PK

RED

GN BN

CONTROL MODULE

(8 PIN)

CONNECTOR

H.V.DIODE

H.V. CAPACITOR

BL WH GN

RDWH

BN(NC)(C)

CN4

TURNTABLE

MOTOR

SECONDARY

INTERLOCK

SWITCH

WH RD

RC RS

HUMIDITY

SENSOR

RELAY 1

RELAY 2

L.V. TRANSFORMER

(CN1)

FUSE

20A

PRIMARY INTERLOCK SWITCH (NO)

MONITOR SWITCH

H.V.TRANSFORMER

FAN

MOTOR

OVEN LAMP

MGT/OVEN

THERMOSTAT

AC 120V/60Hz SINGLE PHASE ONLY

MAGNETRON

321

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CLOCK

LESS

B. MATRIX CIRCUIT FOR TOUCH KEY BOARD

-8-

N.C

QUICK

COOK

TIME

KITCHEN

TIMER

USER

CHOICE

N.C

AUTO

DEFROST

QUICK

TOUCH

COOK

START

SENSOR

COOK

SENSOR

REHEAT

STOP/

CLEAR

SENSOR

POPCORN

N.C

POWER

3 4 5 6 7

Figure 4

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7. OPERATING PROCEDURES A. OVEN CONTROL PANEL

-9-

Display Window- Shows: * Time of day. * Cooking time. * Cooking power level. It also function as a countdown timer when cooking.

Quick Touch

Pre-set timing used for certain food items.

Used in setting Time of Day.

Used in setting Auto Defrost.

Used to set cooking time quickly and directly.

NOTE: A "beep" sounds when you touch a "key" on the control panel, to indicate that you have entered a setting.

Clock

Auto Defrost

Kitchen Timer-

You can use your microwave oven as a timer.

Numbers-

Used to enter the: * Time of day. * Cooking time. * Cooking power. * Food weight for defrost.

Used to set cooking time.

Starts the oven.

Cook Time

Stop/Clear-

Stops the oven and clears all entries except CLOCK. Once cooking has begun, however, CLEAR will function only after STOP has been touched.

Start

Quick On

Power-

Used select cooking power level.

Figure 5

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B. PANEL INSTRUCTIONS

The entire operation is done by simple touch control pads.

(1) DISPLAY WINDOW

The display includes a clock and indicators to tell you time of day, cooking time setting and cooking functions selected.

(2) COOK TIME Key

The TIME key is used to set the cooking time. Touch the TIME key and then the number keys that correspond to the desired cooking time. The remaining time is continuously displayed during cooking.

(3) CLOCK Key

Used in setting CLOCK.

(4) AUTO DEFROST key (DEFROST MEAT, POULTRY

& FISH) Used in setting AUTO DEFROST.

(5) POWER Key

Used to select cooking power level.

(6) STOP/CLEAR Key

Used to stop the oven or clear all entries except CLOCK.

(7) START Key

Touch the START key after setting the desired cooking times etc. Also touch the START key to resume cooking after the cooking is temporarily stopped by opening the door. The key will not function unless the door is closed.

(8) QUICK ON Key

Used in setting cooking time quickly and directly.

(9) QUICK TOUCH COOKING key

Pre-set timing used for certain food item.

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C. EASY USE CHART

(1) CLOCK

1. Touch STOP/CLEAR.

2. Touch CLOCK.

3. Touch numbers for correct time of day.

4. Touch START.

(2) “HI-POWER” COOKING

1. Touch STOP/CLEAR.

2. Touch COOK TIME.

3. Touch numbers for desired cooking time.

4. Touch START.

(3) “MULTI-STAGE” COOKING

1. Touch STOP/CLEAR.

2. Touch COOK TIME.

3. Touch numbers for cooking time.

4. Touch POWER.

5. Touch number for cooking power level.

6. Repeat steps 2-5 to set 2nd cooking stage.

7. Touch START.

(4) CHILD LOCK

To set:

1. Touch STOP/CLEAR.

2. Touch “START” more than 2 seconds. To cancel:

1. Touch STOP/CLEAR.

2. Touch “START” more than 2 seconds.

(5) KITCHEN TIMER

1. Touch STOP/CLEAR.

2. Touch KITCHEN TIMER.

3. Touch correct numbers for time.

4. Touch START.

(6) QUICK ON COOKING

1. Touch STOP/CLEAR.

2. Touch QUICK ON.

3. Touch number for desired minutes.

(7) AUTO DEFROST

1. Touch STOP/CLEAR.

2. Touch AUTO DEFROST. Three different defrosting levels are provided. (MEAT, POULTRY, FISH)

3. Enter the weight of your food in decimal increments from 0.1 to 6.0 pounds.

4. Touch START

5. At beeping, turn food over by following the instructions in the manual.

6. After turning food over, touch START to resume defrosting.

(8) QUICK TOUCH COOKING

1. Touch STOP/CLEAR.

2. Select one of categories, and then touch the number.

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8. PROCEDURE FOR MEASURING MICROWAVE ENERGY LEAKAGE

A. CAUTIONS

(1) Be sure to check a microwave emission prior to

servicing the oven if the oven is operative prior to servicing.

(2) The service personnel should inform the

manufacturer, importer, or assembler of any certified oven unit found to have a microwave emission level in excess of 5mW/cm.sq. and should repair any unit found to have excessive emission levels at no cost to the owner and should ascertain the cause of the excessive leakage. The service personnel should instruct the owner not to use the unit until the oven has been brought into compliance.

(3) If the oven operates with the door open, the service

personnel should;

- Tell the user not to operate the oven

- Contact the manufacturer and CDRH (Center for Devices and Radiological Health) immediately. NOTE: Address on CDRH Office of Compliance (HFZ-312) Center for Devices and Radiological Health 1390 Piccard Drive Rockville, Maryland 20850

(4) The service personnel should check all surface and

vent openings for microwave emission testing.

(5) Check for microwave energy leakage after every

servicing. The power density of the microwave radiation leakage emitted by the microwave oven should not exceed 1mW/cm.sq. And always start measuring of an unknown field to assure safety for operating personnel from radiation leakage. NOTE: The standard is 5mW/cm.sq. while in the customer’s home. 1mW/cm.sq. stated here is manufacturer’s own voluntary standard for units in customer’s home.

EQUIPMENT

Electromagnetic energy leakage monitor (NARDA 8100B, HOLADAY HI 1501) 600cc glass beaker

Glass thermometer 1000C

B. MEASURING MICROWAVE ENERGY LEAKAGE

(1) Pour 275 15cc of 20 50C water in a beaker which is

graduated to 600 cc, and place the beaker in the center of the oven.

(2) Set the energy leakage monitor to 2,450 MHz and use

it following the manufacturer’s recommended test procedure to assure correct result.

(3) When measuring the leakage, always use the 2 inch

(5cm) spacer supplied with the probe. (4) Operate the oven at its maximum output. (5) Measure the microwave radiation using and

electromagnetic radiation monitor by holding the

probe perpendicular to the surface being

measured. (See Figure 7)

C. MEASUREMENT WITH THE OUTER CASE

REMOVED

(1) When you replace the magnetron, measure for

microwave energy leakage before the outer case is

installed and after all necessary components are

replaced or adjusted. Special

care should be taken in measuring the following parts.

- Around the magnetron

- The waveguide

WARNING: AVOID CONTACTING ANY HIGH

VOLTAGE PARTS.

-12-

Move probe along shaded area.

Probe scanning speed less than 2.5 cm/sec.

Figure 7

Figure 6

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D. MEASUREMENT WITH A FULLY ASSEMBLED

OVEN

(1) After all components, including the outer panels, are

fully assembled, measure for microwave energy leakage around the door viewing window, the exhaust opening and air inlet openings.

(2) Microwave energy leakage must not exceed the

values prescribed below.

NOTES:

Leakage with the outer panels removed - less than 5mW/cm.sq. Leakage for a fully assembled oven (Before the latch switch (primary) is interrupted) with the door in a slightly opened position - less than 1 mW/cm .sq.

E. NOTE WHEN MEASURING

(1) Do not exceed meter full scale deflection. (2) The test probe must be removed no faster than 1

inch/sec (2.5cm/sec) along the shaded area, otherwise a false reading may result.

(3) The test probe must be held with the grip portion of

the handle. A false reading may result if the operator’s hand is between the handle and the probe.

(4) When testing near a corner of the door, keep the

probe perpendicular to the surface making sure the probe horizontally along the oven surface, this may possibly cause probe damage.

F. RECORD KEEPING AND NOTIFICATION AFTER

MEASUREMENT

(1) After adjustment and repair of any microwave energy

interruption or microwave energy blocking device, record the measured values for future reference. Also enter the information on the service invoice.

(2) Should the microwave energy leakage not be more

than 1mW/cm.sq. after determining that all parts are in good condition, functioning properly and genuine replacement parts which are listed in this manual have been used.

(3) At least once a year, have the electromagnetic

energy leakage monitor checked for calibration by its manufacturer.

G. POWER OUTPUT MEASUREMENT

(1) Fill the test beaker with 59 ˚F(15 ˚C) ~ 75 ˚F(24 ˚C)

1 liter tap water.

(2) Stir the water in the beaker with thermometer

( ˚F or ˚C) and measure temperature as T1. (3) Place the beaker on the center of turntable. (4) Set for one (1) minute and three (3) seconds and operate

the oven at high power.

NOTE: The additional three (3) seconds is to allow the

magnetron to begin generating power.

(5) When the heating is finished, stir the water again with

thermometer and measure the temperature of water as

T2. (6) Subtract T1 from T2, this will give you the temperature

rise. (7) The microwave power output is within specification, if the

temperature rise is as shown below:

Temperature Rise

Line Voltage Degrees ˚F Degrees ˚C

120 V 11.7 ~ 17.1 6.5 ~ 9.5 108 V Min. 10.8 Min 6

(8) Power output will be influenced by line voltage of power

supply. Consequently, correct power output must be

measured within 120V AC 1 Volt while unit is

operating.

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SPECIAL TIP

• This oven used the button head screws.

• When you remove the screws, using the tamper-resistant Torx driver have a pin-in-head.

Button Head

(Torx style 2)

Page 15

9. DISASSEMBLY INSTRUCTIONS

IMPORTANT NOTES:

UNIT MUST BE DISCONNECTED FROM ELECTRICAL OUTLET WHEN MAKING REPAIRS, REPLACEMENTS, ADJUSTMENTS AND CONTIN-UITY CHECKS. WAIT AT LEAST ONE MINUTE, UNTIL THE HIGH VOLTAGE CAPACITOR IN THE HIGH VOLTAGE POWER SUPPLY HAS FULLY DISCHARGED. THE CAPACITOR SHOULD BE DISCHARGED BY USING INSULATED WIRE - I.E. TEST PROBE CONNECTED TO 10K-OHM RESISTOR IN SERIES TO GROUND. WHEN RECONNECTING THE WIRE LEADS TO ANY PART, MAKE SURE THE WIRING CONNE-CTIONS AND LEAD COLORS ARE CORRECTLY MATCHED ACCORDING TO THE OVERALL CIR-CUIT DIAGRAM. (ESPECIALLY SWITCHES AND HIGH VOLTAGE CIRCUIT.)

A. REMOVING OUT CASE (Figures 8)

(1) Remove three screws from the rear section. (2) Remove one screw from the side section. (3) Push the outer case back about 1 inch (3cm). (4) Lift the case from the set.

B. REMOVING POWER AND CONTROL CIRCUIT

BOARD(Figure 9)

(1) Open the door. (2) Remove two screws, securing the circuir board. (3) Disconnect the lead wire from RELAY(RY2) on the

circuit board.

(4) Lift up and pull out control panel assembly carefully

from the cavity.

(5) Disconnect the lead wire from connector(CN1) on the

circuit board.

CAUTION: DISCHARGE THE HIGH VOLTAGE

CAPACITOR BEFORE SERVICING.

(6) Pull down and remove the circuit board from the

control panel.

(7) Remove the F.P.C connector from the terminal

socket.

-14-

Lift up and pull out control panel

securing screw

ground screw

Remove screw

Figures 9

Figure 8

F.P.C.Connector

Control Panel

Circuit Board

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C. DOOR GROSS ASSEMBLY REMOVAL

(1) Open the door. (2) Remove the choke cover cap very carefully with a flat-

blade screwdriver.

CAUTION : Be careful not to damage door seal plate with

the screwdriver.

(3) Lift up and pull out the door.

NOTE:

1. After replacing the door, be sure to check that the primary switch, monitor switch, and secondary switch operate normally.

2. After replacing the door, check for microwave energy leakage with a survey meter. Microwave energy must be below the limit of 5 mW/cm.sq. (with a 275 ml water load)

3. When mounting the door assembly to the oven assembly, be sure to adjust the door assembly parallel to the chassis. Also adjust so the door has no play between the inner door surface and oven frame assembly. If the door assembly is not mounted properly, microwaves may leak from the clearance between the door and the oven.

-15-

Remove choke cover cap

Door seal plate

Remove choke cover cap

Figure 10

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D. MAGNETRON REMOVAL

(1) Disconnect the wire lead from the magnetron. (2) Carefully remove the mounting screws holding the

magnetron and the waveguide.

(3) Remove the magnetron assembly until the tube is

clear from the waveguide.

NOTE:

1. When removing the magnetron, make sure its dome does not hit any adjacent parts, or it may be damaged.

2. When replacing the magnetron, be sure to install the magnetron gasket in the correct position and be sure that the gasket is in good condition.

3. After replacing the magnetron, check for microwave leakage with a survey meter around the magnetron. Microwave energy must be below the limit of 5 mW/cm2. (With a 275 ml. water load).

Make sure that gasket is rigidly attached to the

magnetron. To prevent microwave leakage, tighten

the mounting screws properly, making sure there is no gap between the waveguide and the magnetron.

E. SUCTION GUIDE MAIN ASSEMBLY

NOTE: To repair any of them, the Suction Guide Main

ASS’Y should be removed first. (1) Disconnect the wire lead from the high voltage

transformer primary terminal, thermostat, fuse holder, and turn table motor connector.

(2) Remove three screws holding the Suction Guide Main

ASS’Y to oven cavity.

(3) Rotate right and pull out Suction Guide Main ASS’Y from

the oven.

Magnetron

Waveguide

Magnetron Gasket

Magnetron

Dome Waveguide

Bracket

Figures 11

Rotate right and pull out

Pull out suction guide main ASS’Y

Screw

Remove screw

Figures 12

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Page 18

G. HIGH VOLTAGE TRANSFORMER REMOVAL

(1) Discharge the high voltage capacitor. (2) Disconnect the wire lead from magnetron, high voltage

transformer, and capacitor.

(3) Remove the screw holding the high voltage transformer

to the base-plate.

F. FAN MOTOR ASSEMBLY REMOVAL

NOTE: To repair any of them, the Suction Guide Main

ASS’Y should be removed first. (1) Disconnect the wire lead from fan motor. (2) Remove the fan. (3) Remove the two screws holding the fan motor assembly

to the suction guide ass’y.

-17-

Suction Guide

H.V. Diode

H.V. Capacitor

Fan Motor ASS’Y

Figures 14

Figures 15

MODEL 721.69252990

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H. REMOVING SENSOR

1) Disconnect the leadwire from PCB Assembly.

2) Remove a screw securing the sensor duct.

Figures 16

Page 19

I. HIGH VOLTAGE CAPACITOR AND DIODE REMOVAL

(1) Discharge the high voltage capacitor. (2) Disconnect the wire lead from the high voltage capacitor. (3) Remove the screw holding the high voltage capacitor

bracket.

J. REMOVING THE TURNTABLE MOTOR

(1) Remove the glass turntable & the rotating ring ASS’Y

by hand.

(2) Remove the turntable motor cover.

The turntable base cover is easily removed by

pinching the six parts with wire cutting pliers.

(3) Disconnect the wire lead from the turntable motor

terminals.

(4) Remove the screw securing the turntable motor to the

oven cavity assembly.

(5) After repairing the motor, rotate the removed turntable

motor cover.

(6) Fit the turntable motor cover's projecting part to the

base plate slit.

NOTE:

1. Remove the wire lead from the turntable motor VERY CAREFULLY.

2. Be sure to grasp the connector, not the wires, when removing.

K. INTERLOCK SYSTEM

(1) INTERLOCK MECHANISM

The door lock mechanism is a device which has been specially designed to eliminate completely microwave activity when the door is opened during cooking and thus to prevent the danger resulting from the microwave leakage.

(2) MOUNTING OF THE PRIMARY/MONITOR/

SECONDARY SWITCHES TO THE LATCH BOARD

(3) INSTALLATION AND ADJUSTMENT OF THE

LATCH BOARD TO THE OVEN ASSEMBLY

• Mount the latch board to the oven assembly.

• Adjust the latch board in the arrow direction so that

oven door will not have any play in it when the door is closed.

• Tighten the mounting screw.

• Check for play in the door by pushing the door release button. Door movement should be less than

0.5 mm. (1/64 inch)

Don't push the door release button while making this

adjustment. Make sure that the latch moves smoothly after adjustment is completed and that the screws are tight. Make sure the primary, monitor, and secondary switches operate properly by following the continuity test procedure.

-18-

Wire Leads

Turntable Motor

PRIMARY SWITCH

ADJUSTMENT DIRECTION

MONITOR SWITCH

SECONDARY SWITCH

Figures 17

Figures 18

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-19-

A. PRIMARY INTERLOCK SWITCH TEST

When the door release button is depressed slowly with the door closed, an audible click should be heard at the same time or successively at intervals. When the button is released slowly, the latches should activate the switches with an audible click. If the latches do not activate the switches when the door is closed, the switches should be a adjusted in accordance with the adjustment procedure. Disconnect the wire lead from the primary switch. Connect the ohmmeter leads to the common (COM) and normally open (NO) terminal of the switch. The meter should indicate an open circuit in the door open condition. When the door is closed, the meter should indicate a closed circuit. When the primary switch operation is abnormal, make the necessary adjustment or replace the switch only with the same type of switch.

B. SECONDARY INTERLOCK SWITCH TEST

Disconnect the wire lead from the secondary switch. Connect the ohmmeter leads to the common (COM) and normally open (NO) terminals of the switch. The meter should indicate a open circuit in the door open condition. When the door is closed, meter should indicate an closed circuit. When the secondary switch operation is abnormal, make the necessary adjustment or replace the switch only with the same type of switch.

C. MONITOR SWITCH TEST

Disconnect the wire lead from the monitor switch. Connect the ohmmeter leads to the common (COM) and normally closed (NC) terminals of the switch. The meter should indicate closed circuit in the door open condition. When the door is closed, meter should indicate an open circuit. When the monitor switch operation is abnormal, replace with the same type of switch. NOTE: After repairing the door or the interlock system, it is necessary to do this continuity test before operating the oven.

WARNING : FOR CONTINUED PROTECTION AGAINST EXCESSIVE RADIATION

EMISSION, REPLACE ONLY WITH IDENTICAL REPLACEMENT PARTS.

TYPE NO. SZM-V 16-FA-63 OR VP-533A-OF FOR PRIMARY SWITCH TYPE NO. SZM-V 16-FA-62 OR VP-532A-OF FOR MONITOR SWITCH TYPE NO. SZM-V 16-FA-63 OR VP-533A-OF FOR SECONDARY SWITCH

COMPONENTS TEST PROCEDURE RESULTS

SWITCHES Check for continuity of the Door Door (Wire leads removed) switch with an Ohm-meter open closed

Primary Switch

Monitor Switch

Secondary Switch

NOTE : After checking for the continuity of switches, make sure that they are

connected correctly.

COM

10. INTERLOCK CONTINUITY TEST

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-20-

CAUTIONS

1. DISCONNECT THE POWER SUPPLY CORD FROM THE OUTLET WHENEVER REMOVING THE OUTER CASE FROM THE UNIT. PROCEED WITH THE TEST ONLY AFTER DISCHARGING THE HIGH VOLTAGE CAPACITOR AND REMOVING THE WIRE LEADS FROM THE PRIMARY WINDING OF THE HIGH VOLTAGE TRANSFORMER.

2. ALL OPERATIONAL CHECKS WITH MICROWAVE ENERGY MUST BE DONE WITH A LOAD (1 LITER OF WATER IN CONTAINER) IN THE OVEN.

COMPONENTS TEST PROCEDURE RESULTS

HIGH VOLTAGE TRANSFORMER (Wire leads removed)

MAGNETRON (Wire leads removed)

1. Measure the resistance. (Ohm-meter scale: Rx1 and Rx100)

• Primary winding

• Secondary winding

• Filament winding

2. Measure the resistance. (Ohm-meter scale: Rx1000)

• Primary winding to ground

• Filament winding to ground

1. Measure the resistance. (Ohm-meter scale: Rx1)

• Filament terminal

2. Measure the resistance. (Ohm-meter scale: Rx1000)

• Filament to chassis

Approx.: 0.2 ~ 0.4 ohm Approx.: 50 ~ 90 ohm Less than: 1 ohm

Normal: Infinite Normal: Infinite

Normal: Less than 1 ohm

Normal: Infinite

PRIMARY TERMINAL

SECONDARY TERMINAL

FILAMENT WINDING TERMINAL

11. TEST AND CHECKOUT PROCEDURES, AND TROUBLESHOOTING

A. TEST PROCEDURES

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-21-

COMPONENTS TEST PROCEDURE RESULTS

HIGH VOLTAGE CAPACITOR

HIGH VOLTAGE DIODE

NOTE : Some inexpensive meters may indicate infinite resistance in both direction.

Measure the resistance. (Ohm-meter scale: Rx1000)

• Terminal to terminal.

Measure the resistance. (Ohm-meter scale: Rx1000)

• Terminal to case.

Measure the continuity (Forward). (Ohm-meter scale: Rx10000)

Measure the continuity (Reverse). (Ohm-meter scale: Rx10000)

Normal: Momentarily indicates

several ohms, and then gradually returns to infinite.

Normal: Infinite.

Normal: Continuity. Abnormal: Infinite.

Normal: Infinite. Abnormal: Continuity.

NOTE: When testing the magnetron, be sure to install the magnetron gasket

in the correct position and be sure that the gasket is in good condition.

Antenna Gasket

Chassis

Filament

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COMPONENTS TEST PROCEDURE RESULTS

RELAY 2

FAN MOTOR (Wire leads removed)

TURNTABLE MOTOR (Wire leads removed)

SENSOR

Check for continuity of relay 2 with an ohmmeter. (Remove wire leads from relay 2 and operate the unit.)

Measure the resistance. (Ohm-meter scale: R x 100)

Measure the resistance. (Ohm-meter scale: R x 1000)

1) Disconnect sensor connector from micom computer board.

2) Measure resistance terminal to terminal (ohm meter scale: R X 1000)

POWER LEVEL

1 4 sec 18 sec 2 6 sec 16 sec 3 8 sec 14 sec 4 10 sec 12 sec 5 12 sec 10 sec 6 14 sec 8 sec 7 16 sec 6 sec 8 18 sec 4 sec 9 20 sec 2 sec

10 22 sec 0 sec

Normal: Approx. 65 ~ 80 ohm Abnormal: Infinite or several

ohm.

Normal: Approx. 2 ~ 4K ohm Abnormal: Infinite or several

ohm.

Normal: Approximately

BK - RD: 6.2 Kohm RD - WH: 3.1 Kohm

BK - WH: 3.1 Kohm Abnormal: Infinite or several. * Sensor cooking condition

1. Oven should be plugged in at

least 5 minutes before sensor cooking.

2. Room temperature should not

exceed 95

°F .

3. Be sure the exterior of the

cooking container and the interior of the oven are dry. Wipe each off with paper towel.

4. The oven will not generate

microwave energy for the first 28 seconds of the sensor cooking cycle.

NOTE : • A MICROWAVE LEAKAGE TEST MUST ALWAYS BE PERFORMED

WHEN THE UNIT IS SERVICED FOR ANY REASON.

• MAKE SURE THE WIRE LEADS ARE IN THE CORRECT POSITION.

• WHEN REMOVING THE WIRE LEADS FROM THE PARTS, BE SURE

TO GRASP THE CONNECTOR, NOT THE WIRES.

Relay 2

1 2 3

Page 24

-23-

B. CHECKOUT PROCEDURES

(1) CHECKOUT PROCEDURES FOR FUSE BLOWING

CAUTION: REPLACE BLOWN FUSE WITH 20 AMPERE FUSE.

Fuse blows immediately after the door is closed.

Fuse blows immediately after the door is opened.

Fuse blows when the door is closed and START key is touched.

Improper operation of the primary interlock, secondary interlock switches and/or the interlock monitor switch.

Malfunction of the high voltage transformer; the high voltage capacitor including the diode, the magnetron, the blower motor or the circuit board.

PROBLEMS CAUSES

NOTES:

- If the fuse is blown by an improper switch operation, replace the defective switches and the fuse at the same time. After replacing the defective switches with new ones, make sure that they are correctly connected.

- Check for microwave energy leakage according to “1. ADJUSTMENT PROCEDURES” on page 3, when the primary interlock, secondary interlock switches and/or the interlock monitor switches are adjusted or replaced.

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(2) CHECKOUT PROCEDURES FOR RELAY

- PROBLEM (A) FAN motor and oven lamp turn on without touching START key when the door is closed.

Remove the mate connector of I/O CON from the circuit board does the unit still operate?

GOOD

Replace the circuit board

- PROBLEM (B) FAN motor and oven lamp turn on When the door is closed and START key is touched.

Check the interlock switches

Replace the micro switches.

Defective RELAY or poor connection of relay

Replace RELAY or correct the connection.

YES

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(3) CHECKOUT PROCEDURES FOR CIRCUIT BOARD

The following symptoms indicate a defective circuit board. (1) The start function fails to operate but the high

voltage Systems, the interlock switches, the door sensing and the relay check good.

(2) The unit with a normal relay continuously

operates.

(3) The buzzer does not sound or continues to sound.

(4) Some segments of one or more digits do not light up,

or they continue to light up, or segments light when

they should not. (6) Wrong figures appear. (7) The figures of all digits flicker. (8) Some of the indicators do no light up. (9) The clock does not keep time properly.

-25-

NOTE: A MICROWAVE ENERGY LEAKAGE TEST MUST ALWAYS BE PERFORMED WHEN THE UNIT IS

SERVICED FOR ANY REASON.

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Page 27

C. TROUBLE SHOOTING

WHEN YOU GET A COMPLAINT FROM YOUR CUSTOMER, EVALUATE THE COMPLAINT CAREFULLY. IF THE FOLLOWING SYMPTOMS APPLY, PLEASE INSTRUCT THE CUSTOMER IN THE PROPER USE OF THE MICROWAVE OVEN. THIS CAN ELIMINATE AN UNNECESSARY SERVICE CALL.

CAUTIONS

1. Check grounding before checking for trouble.

2. Be careful of the high voltage circuit.

3. Discharge the high voltage capacitor.

4. When checking the continuity of the switches or of the high voltage transformer, disconnect one lead wire from these parts and then check continuity with the AC plug removed. To do otherwise may result in a false reading or damage to your meter.

5. Do not touch any part of the circuit on the PCB since static electric discharge may damage this control panel. Always touch yourself to ground while working on this panel to discharge any static charge built up in your body. (Micom model only)

CONDITION

Microwave oven

does not work.

Inserting many plugs into one outlet and using them at the same time. (blown fuse or breaker)

Microwave oven plug is not inserted tightly.

Output power is too low. Low AC input voltage.

Food temperature is too low.

Using metallic ware and allowing it to touch the oven wall.

Sparks occur.

Inconsistent intensity of microwave by their characteristics.

1. Use plastic wrap or lid.

2. Stir once or twice while cooking soup, cocoa or milk, etc.

Uneven cooking.

Ceramic ware trimmed in gold or silver powder is used.

Avoid using other electrical appliances when you use the microwave oven.

Insert microwave oven plug securely.

Use the microwave oven at adequate line voltage.

This may not be a defect. It is possible that the food should be cooked for a longer time period.

Do not use metallic ware for cooking except where noted in the cooking guide.

Do not use any type of cookware with metallic trimming.

CAUSE REMEDY

-26-

MODEL 721.69252990

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Page 28

1. Incomplete segments.

• Segment missing.

• Partial segment missing.

• Digit flickering (NOTE: Slight flickering is normal.)

2. Colon does not turn on or blink.

3. A distinct change in the brightness of one or more numbers in display.

4. One or more digits in the display are not lighting.

5. Display indicates a number different from one touched, for example, key in 5 and 3 appears in the display.

6. Specific numbers (for example 7 or 9) will not display when key pad is touched.

7. Display does not count down with time blinking or up with clock operation.

8. Display obviously jumps in time while counting down.

9. Display counts down too fast while cooking.

10. Each indicator light does not turn on after setting cooking cycle.

11. Display time of day does not reappear when cooking is finished.

(TROUBLE 1)

The following visual conditions indicate a probable defective control circuit.

CONDITION CHECK RESULT CAUSE REMEDY

1. No input can be programmed.

Continuity

No continuity

Defective PCB assembly.

Loose connection.

Replace PCB assembly.

Connect them tightly.

Check the connection between membrane key assembly and PCB assembly.

2. Some inputs cannot be programmed.

3. Display shows a number or figure different from one touched.

4. Random programming when touching other pads.

5. Display is fixed at some figure and can not accept any input.

Everything works as specified.

Still have trouble.

Defective key membrane assembly.

Defective PCB assembly.

Replace key membrane assembly.

Replace PCB assembly.

Replace key membrane assembly and check operation.

MODEL 721.69252990

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Page 29

CONDITION CHECK RESULT CAUSE REMEDY

1. Fuse blows. Continuity.

No continuity.

Continuity.

Shorted contact at the primary switch.

Replace fuse, primary, monitor switches, and RELAY(RY2) of P.C.B Assembly.

No continuity.

Normal.

Defective high voltage capacitor.

Replace high voltage capacitor.

Fuse blows again

Defective high voltage transformer.

Replace high voltage transformer.

Malfunction of the monitor switch.

Replace fuse, primary, monitor switches, and RELAY(RY2) of P.C.B Assembly.

Check continuity of monitor switch (with door closed).

Check continuity of primary switch (with door opened).

Disconnect one side of the wire lead connected from transformer to the high voltage capacitor and operate the unit.

Replace fuse

2. Fuse does not blow.

No continuity.

Continuity.

No continuity.

Defective power supply cord.

Replace power supply cord.

Defective thermostat.

Replace thermostat.

Check continuity of thermostat.

Check continuity of power supply cord.

(TROUBLE 2)

Oven does not operate at all, Display window does not display any figures,

and no input is accepted.

-28-

MODEL 721.69252990

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Page 30

CONDITION CHECK RESULT CAUSE REMEDY

1. Setting time does not count down when touching START pad.

2. Fan motor or oven lamp do not turn on.

No continuity.

Continuity.

Continuity

Defective PCB assembly.

Loose connection.

Replace PCB assembly.

Connect them tightly.

No continuity

Abnormal

Check fan motor.

Defective fan motor. Replace fan motor.

Abnormal

Normal

Check oven lamp.

Defective oven lamp. Replace oven lamp.

Defective secondary switch.

Replace secondary switch.

Check continuity of secondary switch (with door closed).

Check the connection between CN1 connector and PCB assembly.

(TROUBLE 3)

Display shows all figures set, but oven does not start cooking while desired

program times are set and START pad is touched.

(TROUBLE 4) Oven seems to be operating but little heat is produced in oven load.

NOTE :

Simple test of power output-conducted by heating one liter water for one min. if available. Minimum 8.5°C temperature rise is normal condition.

CONDITION CHECK RESULT CAUSE REMEDY

Output is low

Lower than 90% of rating voltage.

Normal

Abnormal

Defective PCB assembly.

Replace PCB assembly.

Normal

Abnormal

Measure the output power.

Defective magnetron.

Replace magnetron.

Decrease in power source voltage with load.

Suggest customer contact local electric power utility co. or qualified electrician.

Check the power source voltage.

Disconnect the wire leads from relay 2 and check on and off time with multitester.

-29-

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Page 31

CONDITION CHECK RESULT CAUSE REMEDY

No microwave oscillation.

No continuity.

Continuity.

Abnormal

Defective high voltage transformer.

Replace high voltage transformer.

Normal

Defective PCB assembly.

Replace PCB assembly.

Disconnect the wire leads from relay 2 and check continuity of relay 2. (Operate the unit)

Check high voltage transformer

Output is full power when you set lower power level.

Abnormal.

Defective PCB assembly.

Replace PCB assembly.

Disconnect the wire leads from relay 2 and check continuity relay 2. (Operate the unit)

Abnormal

Defective high voltage capacitor.

Replace high voltage capacitor.

Normal

Check high voltage capacitor.

Abnormal

Defective high voltage diode.

Replace high voltage diode.

Normal

Check high voltage diode.

Abnormal

Defective magnetron.

Replace magnetron.

Check magnetron.

(TROUBLE 5)

No microwave oscillation even though oven lamp and fan motor run. (Display operates properly)

NOTE : • Make sure the wire leads correct position.

• When Removing the wire leads from the parts, be sure to grasp the connector, not the wires.

• When removing the magnetron, be sure to install the magnetron gasket in the correct position

and in good condition.

-30-

MODEL 721.69252990

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Page 32

KENMORE MICROWAVE OVEN

MODEL NO. 721.69252990

721.69259990

INTRODUCTION

-1-

JUNE. 1999

*** ALL SERVICE ON MICROWAVE OVENS SHOULD BE PERFORMED BY A QUALIFIED TECHNICIAN USING

APPROVED TESTING EQUIPMENT. CUSTOMERS SHOULD NOT ATTEMPT TO REPLACE PARTS IDENTIFIED BY A TRIPLE ASTERISK(***)

DOOR PARTS

CONTROL PANEL PARTS

INTERIOR PARTS

SUCTION GUIDE MAIN PARTS

BASE PLATE PARTS

OVEN CAVITY PARTS

SENSOR PARTS

Page 33

-2-

DRAWING NO: 1

KENMORE MICROWAVE OVEN

MODEL NO. 721.69252990

721.69259990

DOOR PARTS

*** ALL SERVICE ON MICROWAVE OVENS SHOULD BE PERFORMED BY A QUALIFIED TECHNICIAN USING

APPROVED TESTING EQUIPMENT. CUSTOMERS SHOULD NOT ATTEMPT TO REPLACE PARTS IDENTIFIED BY A TRIPLE ASTERISK(***)

JUNE. 1999

13581A

13552A

13213A

13536A

14026A

14970A

13720D

13352A

Page 34

DRAWING NO: 1

KENMORE MICROWAVE OVEN

MODEL NO. 721.69252990

721.69259990

DOOR PARTS

(See Illustration “DOOR PARTS”)

N.S.P (NOT SERVICE PART): THESE PARTS ARE NOT AVAILABLE AS REPAIR PARTS BECAUSE THEY ARE TOO COSTLY OR NOT PRACTICAL TO REPLACE OR NEVER EXPECTED TO FAIL DURING THE LIFE EXPECTANCY OF THE UNIT. * ITEMS NOT ILLUSTRATED.

*** ALL SERVICE ON MICROWAVE OVENS SHOULD BE PERFORMED BY A QUALIFIED TECHNICIAN USING

APPROVED TESTING EQUIPMENT. CUSTOMERS SHOULD NOT ATTEMPT TO REPLACE PARTS IDENTIFIED BY A TRIPLE ASTERISK(***)

-3-

JUNE. 1999

Page 35

KENMORE MICROWAVE OVEN

MODEL NO. 721.69252990

721.69259990

CONTROLLER PARTS

-4-

DRAWING NO: 2

*** ALL SERVICE ON MICROWAVE OVENS SHOULD BE PERFORMED BY A QUALIFIED TECHNICIAN USING

APPROVED TESTING EQUIPMENT. CUSTOMERS SHOULD NOT ATTEMPT TO REPLACE PARTS IDENTIFIED BY A TRIPLE ASTERISK(***)

26638A

23572A

23550D

WTT028

268711

WTP018

24510L

24781M

24970A

250201

JUNE. 1999

Page 36

KENMORE MICROWAVE OVEN

MODEL NO. 721.69252990

721.69259990

CONTROL PANEL PARTS

(See Illustration “CONTROLLER PARTS”)

-5-

DRAWING NO: 2

*** ALL SERVICE ON MICROWAVE OVENS SHOULD BE PERFORMED BY A QUALIFIED TECHNICIAN USING

APPROVED TESTING EQUIPMENT. CUSTOMERS SHOULD NOT ATTEMPT TO REPLACE PARTS IDENTIFIED BY A TRIPLE ASTERISK(***)

JUNE. 1999

Page 37

-6-

DRAWING NO: 3

*** ALL SERVICE ON MICROWAVE OVENS SHOULD BE PERFORMED BY A QUALIFIED TECHNICIAN USING

APPROVED TESTING EQUIPMENT. CUSTOMERS SHOULD NOT ATTEMPT TO REPLACE PARTS IDENTIFIED BY A TRIPLE ASTERISK(***)

33052M

340511

36549S

WTP

013

33390G

WTT

020

WSZ

185

33112U

35889A

WTT020

33461Z

34036W

KENMORE MICROWAVE OVEN

MODEL NO. 721.69252990

721.69259990

OVEN CAVITY PARTS

JUNE. 1999

Page 38

KENMORE MICROWAVE OVEN

MODEL NO. 721.69252990

721.69259990

OVEN CAVITY PARTS

(See Illustration “OVEN CAVITY PARTS”)

-7-

DRAWING NO: 3

*** ALL SERVICE ON MICROWAVE OVENS SHOULD BE PERFORMED BY A QUALIFIED TECHNICIAN USING

APPROVED TESTING EQUIPMENT. CUSTOMERS SHOULD NOT ATTEMPT TO REPLACE PARTS IDENTIFIED BY A TRIPLE ASTERISK(***)

JUNE. 1999

Page 39

KENMORE MICROWAVE OVEN

MODEL NO. 721.69252990

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LATCH BOARD PARTS

-8-

DRAWING NO: 4

*** ALL SERVICE ON MICROWAVE OVENS SHOULD BE PERFORMED BY A QUALIFIED TECHNICIAN USING

APPROVED TESTING EQUIPMENT. CUSTOMERS SHOULD NOT ATTEMPT TO REPLACE PARTS IDENTIFIED BY A TRIPLE ASTERISK(***)

43501A

43500A

466002

WSZ085

33461Z

466001

466003

JUNE. 1999

Page 40

KENMORE MICROWAVE OVEN

MODEL NO. 721.69252990

721.69259990

LATCH BOARD PARTS

(See Illustration “OVEN CAVITY PARTS”)

-9-

DRAWING NO: 4

*** ALL SERVICE ON MICROWAVE OVENS SHOULD BE PERFORMED BY A QUALIFIED TECHNICIAN USING

APPROVED TESTING EQUIPMENT. CUSTOMERS SHOULD NOT ATTEMPT TO REPLACE PARTS IDENTIFIED BY A TRIPLE ASTERISK(***)

JUNE. 1999

Page 41

-10-

DRAWING NO: 5

*** ALL SERVICE ON MICROWAVE OVENS SHOULD BE PERFORMED BY A QUALIFIED TECHNICIAN USING

APPROVED TESTING EQUIPMENT. CUSTOMERS SHOULD NOT ATTEMPT TO REPLACE PARTS IDENTIFIED BY A TRIPLE ASTERISK(***)

WSZ002

WTT028

WSZ002

WTT028

WSZ002

WTT037

50CZZH

56324A

54810C

948502

56851D

55900A

56549F

56930V

568771

54974S

55006F

56411A

50FZZA

WSZ002

55262A

56912B

KENMORE MICROWAVE OVEN

MODEL NO. 721.69252990

721.69259990

OVEN INTERIOR PARTS

JUNE. 1999

Page 42

KENMORE MICROWAVE OVEN

MODEL NO. 721.69252990

721.69259990

OVEN INTERIOR PARTS

(See Illustration “LATCH BOARD”)

-11-

DRAWING NO: 5

*** ALL SERVICE ON MICROWAVE OVENS SHOULD BE PERFORMED BY A QUALIFIED TECHNICIAN USING

APPROVED TESTING EQUIPMENT. CUSTOMERS SHOULD NOT ATTEMPT TO REPLACE PARTS IDENTIFIED BY A TRIPLE ASTERISK(***)

JUNE. 1999

Page 43

KENMORE MICROWAVE OVEN

MODEL NO. 721.69252990

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BASE PLATE PARTS

-12-

DRAWING NO: 6

*** ALL SERVICE ON MICROWAVE OVENS SHOULD BE PERFORMED BY A QUALIFIED TECHNICIAN USING

APPROVED TESTING EQUIPMENT. CUSTOMERS SHOULD NOT ATTEMPT TO REPLACE PARTS IDENTIFIED BY A TRIPLE ASTERISK(***)

56170D

WSZ002

948503

WSZ002

WTTO21

63303A

65006B

JUNE. 1999

Page 44

KENMORE MICROWAVE OVEN

MODEL NO. 721.69252990

721.69259990

BASE PLATE PARTS

(See Illustration “BASE PLATE PARTS ”)

-13-

DRAWING NO: 6

*** ALL SERVICE ON MICROWAVE OVENS SHOULD BE PERFORMED BY A QUALIFIED TECHNICIAN USING

APPROVED TESTING EQUIPMENT. CUSTOMERS SHOULD NOT ATTEMPT TO REPLACE PARTS IDENTIFIED BY A TRIPLE ASTERISK(***)

JUNE. 1999

Page 45

KENMORE MICROWAVE OVEN

MODEL NO. 721.69252990

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SENSOR PARTS

-14-

DRAWING NO: 7

*** ALL SERVICE ON MICROWAVE OVENS SHOULD BE PERFORMED BY A QUALIFIED TECHNICIAN USING

APPROVED TESTING EQUIPMENT. CUSTOMERS SHOULD NOT ATTEMPT TO REPLACE PARTS IDENTIFIED BY A TRIPLE ASTERISK(***)

56501A

WTP002

WTT021

54974T

JUNE. 1999

Page 46

KENMORE MICROWAVE OVEN

MODEL NO. 721.69252990

721.69259990

SENSOR PARTS

(See Illustration “SENSOR PARTS ”)

-15-

DRAWING NO: 7

*** ALL SERVICE ON MICROWAVE OVENS SHOULD BE PERFORMED BY A QUALIFIED TECHNICIAN USING

APPROVED TESTING EQUIPMENT. CUSTOMERS SHOULD NOT ATTEMPT TO REPLACE PARTS IDENTIFIED BY A TRIPLE ASTERISK(***)

JUNE. 1999

Page 47

KENMORE MICROWAVE OVEN

MODEL NO. 721.69252990

721.69259990

POWER AND CONTROL CIRCUIT BOARD

-16-

DRAWING NO: 11

COMPONENT SIDE SOLDER SIDE

JUNE. 1999

Page 48

KENMORE MICROWAVE OVEN

MODEL NO. 721.69252990

721.69259990

POWER AND CONTROL CIRCUIT BOARD

(See Illustration “POWER AND CONTROL CIRCUIT BOARD”)

-17-

DRAWING NO: 11

*** ALL SERVICE ON MICROWAVE OVENS SHOULD BE PERFORMED BY A QUALIFIED TECHNICIAN USING

APPROVED TESTING EQUIPMENT. CUSTOMERS SHOULD NOT ATTEMPT TO REPLACE PARTS IDENTIFIED BY A TRIPLE ASTERISK(***)

JUNE. 1999

Page 49

P/NO: 3828W5S1194 Printed in Korea