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R-334 - 25

7. Unclip the noise unit from the fan duct and lift the chassis

support.

8. Unclip  air intake duct from the chassis support.
9. Remove air intake duct.

10. Carefully remove four (4) screws holding magnetron to

waveguide, when removing the screws hold the
magnetron to prevent it from falling.

11. Remove the magnetron from the waveguide with care

so that the magnetron antenna is not hit by any metal
object around the antenna.

CAUTION: WHEN REPLACING THE MAGNETRON, BE

SURE THE R.F. GASKET IS IN PLACE AND
THE MAGNETRON MOUNTING SCREWS
ARE TIGHTENED SECURELY.

1. CARRY OUT 3D CHECKS
2. Remove the one (1) screw holding the noise filter to the

chassis support.

3. Release the noise filter from the tabs of the fan duct.
4. Disconnect the wire leads from the fan motor.
5. Remove the one (1) screw holding the capacitor  holder

to the oven cavity back plate.

6. Remove the one (1) screw holding the fan duct to the

oven cavity back plate.

7. Release the tabs of the capacitor holder from the fan

duct.

8. Remove the fan duct from the oven.
9. Remove the fan blade assembly from the fan motor.
10. Remove the two (2) screws holding the fan motor to the

fan duct.

10. Now, the fan motor is free.

1. CARRY OUT 3D CHECKS

2. Disconnect the main harness from the control panel.
3. Remove the one (1) screw holding the control panel to

the oven cavity.

4. Lift up the control panel assembly and pull it forward.

Now, the control panel assembly is free.

1. Disconnect the oven from power supply.
2. Remove the turntable motor cover by snipping of material

in four corners.

3. Where the corners have been snipped off bend the

corners areas flat. No sharp edges must be evident after
removal of TT motor cover.

4. Disconnect the wire lead from turntable motor and

remove the 1 screw holding the turntable motor.

5. Turntable motor is now free.
6. After replacement use the one (1) screw allocated to fit

the TT motor cover.

1. Remove the turntable motor, refer to “Turntable Motor

Removal”.

2. Pull the coupling out of the hole in the oven cavity.
3. At that time the turntable coupling will be free.

T.T.M
SUPPORT
ANGLE

COUPLING

PACKING

CAUTION: REPLACE THE PACKING AT THE SAME

TIME WHEN REPLACING THE COUPLING.
BECAUSE THE PACKING MAY BE
DAMAGED BY PULLING OUT THE
COUPLING.

1. CARRY OUT 3D CHECKS
2. Release the terminals from the oven lamp.
3. Lift up the oven lamp from its retaining clips.
4. Now, the oven lamp is free.

R-334 - 26

If the monitored latch switch, stop switch and monitor switch
do not operate properly due to a mis-adjustment, the
following adjustment should be made.
1. CARRY OUT 3D CHECKS
2. Loosen the two (2) screws holding the latch hook to the

oven cavity front flange.

3. With door closed, adjust the latch hook by moving it back

and forward, or up and down. In and out play of the door
allowed by the latch hook should be less than 0.5 mm.
The horizontal position of the latch hook should be
placed where the monitor switch and activated with the
door closed. The vertical position of the latch hook
should be placed where the monitored latch switch and
stop switch have activated with the door closed.

4. Secure the screws with washers firmly.
5. Make sure  the monitored, latch switch, stop switch and

monitor switch operation. If those switches have not
activated with the door closed, two (2) screws holding
latch hook to oven cavity front flange and adjust the latch
hook position.

After adjustment, make sure of following:
1. In and out play of door remains less than 0.5 mm when

latched position. First check latch hook position, pushing
and pulling the door toward the oven face. The results
(play of the door) should be less than 0.5 mm.

2. The contacts (COM - NO) of monitored latch switch and

stop switch interrupt the circuit before the door can be
opened.

3. The contacts (COM - NC) of the monitor switch close

when the door is opened.

4. The contacts (COM - NO) of the monitored latch switch

open when the door is opened.

5. Re-install outer case and check for microwave leakage

around the door with an approved microwave survey
meter. (Refer to Microwave Measurement Procedure.)

1. CARRY OUT 3D CHECKS.
2. Remove the control panel assembly referring to

“CONTROL PANEL REMOVAL”.

3. Disconnect the leads from all switches.
4. Remove the two (2) screws holding the latch hook to the

oven cavity.

5. Remove the latch hook.
6. Push the retaining tab slightly and remove the switch.

1. Lift the door and pull.

Stop switch
SW3

Monitor switch
SW2

Monitored latch
switch SW1

Latch Hooks

Stop Switch
SW3

Monitor Switch
SW2

Monitored Latch
Switch SW1

R-334 - 27

1. CARRY OUT 3D CHECKS.
2. Push the open button and open the door slightly.
3. Insert a putty knife (thickness of about 0.5mm) into the

gap between the choke cover and door frame as shown
in Figure C-5 to free engaging parts.

4. Release choke cover  from door panel.
5. Now choke cover is free.

CHOKE COVER

PUTTY KNIFE

DOOR FRAME

6. Release two (2) pins of door panel from two (2) holes of

upper and lower oven hinges by lifting up.

7. Now, door sub assembly is free from oven cavity.
8. Remove the four (4) screws holding the door panel to

the door frame.

9. Release door panel from eight (8) tabs of door frame by

sliding door panel downward.

10. Now, door panel is free.
11. Slide latch head upward and remove it from door frame,

releasing latch spring from door frame and latch head.

12. Now, latch head and latch spring are free.
13. Remove the one (1) screw holding the glass stopper to

the door frame.

14. Remove the glass stopper from the door frame.
15. Slide the front door glass leftwards and then slide

upwards to release the tabs holding it.

16. Now, the front door glass is free

RE-INSTALL
1. Re-install the front door glass to the door frame as

follows.

1) Insert the upper edge of the front door glass into the six

(6) tabs of the door frame.

2) Slide the front door glass downwards and insert the

lower edge of the front door glass into the six (6) tabs of
the door frame.

3) Slide the front door glass rightwards and insert the right

edge of the front door glass into the one (1) tab of the
door frame.

2. Re-install the glass stopper to the door frame as

follows.

1) Re-install the glass stopper to the door frame so that

the two (2) holes of the glass stopper meet the two (2)
pins of the door frame.

2) Hold the glass stopper to the door frame with the one

(1) screw.

3. Re-install the latch spring to the latch head. Re-install

the latch spring to the door frame. Re-install latch
head to door frame.

4. Re-install door panel to door frame by fitting eight (8)

tabs of door frame to eight (8) holes of door panel.

5. Fit the door panel to the door frame with four (4)

screws.

6. Insert two (2) pins of door panel on two (2) hole of

upper and lower oven hinges.

7. Re-install choke cover  to door panel.

PIN

PIN

LOWER
OVEN HINGE

UPPER
OVEN HINGE

LOWER
OVEN HINGE

CHOKE COVER

DOOR
PANEL

DOOR SUB 
ASSEMBLY

SLIT CHOKE

R-334 - 28

After adjustment of door latch switches, monitor switch and
door are completed individually or collectively, the following
leakage test must be performed with a survey instrument
and it must be confirmed that the result meets the require-
ments of the performance standard for microwave oven.

REQUIREMENT
The safety switch must prevent microwave radiation emis-
sion in excess of 5mW/cm2 at any point 5cm or more from
external surface of the oven.

PREPARATION FOR TESTING:
Before beginning the actual test for leakage, proceed as
follows;
1. Make sure that the test instrument is operating normally

as specified in its instruction booklet.
Important:
Survey instruments that comply with the requirement for
instrumentations as prescribed by the performance
standard for microwave ovens must be used for testing.

Recommended instruments are:
NARDA 8100
NARDA 8200
HOLADAY HI 1500
SIMPSON 380M

2. Place the oven tray into the oven cavity.
3. Place the load of 275 

±

 15ml of water initially at 20 

±

 5

°

C

in the center of the oven tray. The water container
should be a low form of 600 ml beaker with inside
diameter of approx. 8.5cm and made of an electrically
non-conductive material such as glass or plastic.
The placing of this standard load in the oven is important
not only to protect the oven, but also to insure that any
leakage is measured accurately.

4. Close the door and turn the oven ON with the timer set

for several minutes. If the water begins to boil before the
survey is completed, replace it with 275ml of cool water.

5. Move the probe slowly (not faster that 2.5cm/sec.) along

the gap.

6. The microwave radiation emission should be measured

at any point of 5cm or more from the external surface of
the oven.