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R-244M - 13

1. CARRY OUT 3D CHECKS.
2. Make sure that a definite "click" can be heard when the

microwave oven door is unlatched. (Hold the door in a
closed position with one hand, then push the door open
button with the other, this causes the latch heads to rise,
it  should then possible to hear a "click" as the door
switches operate.)

3. Visually check the door and cavity face plate for damage

(dents, cracks, signs of arcing etc.).

Carry out any remedial work that is necessary before
operating the oven.
Do not operate the oven if any of the following conditions
exist;
1. Door does  not close firmly.

2. Door hinge, support or latch hook is damaged.
3. The door seal is damaged.
4. The door is bent or warped.
5. There are defective parts in the door interlock system.
6. There are defective  parts in the microwave generating

and transmission assembly.

7. There is visible damage to the oven.

Do not operate the oven:

1. Without the RF gasket (Magnetron).
2. If the wave guide or oven cavity are not intact.
3. If the door is not closed.
4. If the outer case (cabinet) is not fitted.

Removal
1. CARRY OUT 3D CHECKS.
2. Remove the single (1) screw holding the green/yellow

wire to the cavity.

3. Disconnect the leads of the power supply cord from the

noise filter, referring to the Figure C-3 (a).

4. Release the power supply cord from the rear cabinet.
5. Now, the power supply cord is free.

Re-install
1. Insert the moulding cord stopper of power supply cord

into the square hole of the rear cabinet, referring to the
Figure C-3 (b). Installation of Power supply cord.

2. Install the earth wire lead of power supply cord to the

cavity with one (1) screw and nut and tighten the screw.

3. Connect the brown and blue wire leads of power supply

cord to the noise filter correctly, referring to the Pictorial
Diagram.

OVEN CAVITY
BACK PLATE

SQUARE HOLE

MOULDING
CORD
STOPPER

POWER SUPPLY
CORD

GROMMET
MOULDING

OVEN CAVITY
BACK PLATE

BROWN WIRE

POWER 
SUPPLY CORD

CHASSIS SUPPORT

BLUE WIRE

NOISE FILTER

N

L

F1

RED

WHT

EARTH WIRE

14

R-244M -

1. CARRY OUT 3D CHECKS.
2. Disconnect the wire leads from the switches and control

panel.

3. Remove the control panel assembly from the oven cavity

front flange. Referring to chapter "CONTROL PANEL
ASSEMBLY REMOVAL".

4. Remove the two (2) screw holding the latch hook to the

oven flange.

5. Remove the latch hook assembly from the oven flange.
6. To remove the switch.
6-1. With pushing outward on the tab that is holding the

switch, turn the switch so that the post is an axis.

6-2. Pull out the switch from the latch hook. Do not break the

post or tab of the latch hook.

6-3. Now the switch is free.

Re-install
1. Re-install each switch in its place. The monitored latch

switch is in the lower position and the monitor switch is
in the middle position. The stop switch is in the upper
position.

2. Re-connect wire leads to each switch. Refer to  “Pictorial

Diagram”page 17.

3. Secure latch hook (with two (2) mounting screws) to

oven flange.

4. Re-install the control panel assembly to the oven cavity

front flange.

5. Re-connect wire leads to the control unit. Refer to

“Pictorial Diagram”page 17.

6. Make sure that monitor switch is operating properly and

check continuity of the monitor circuit. Refer to chapter

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

flange of the oven front face.

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

and forth and up and down. In and out play of the door
allowed by the upper and lower position of the latch hook
should be less than 0.5mm. The horizontal position of
the latch hook should be adjusted so that the monitor
switch is activated with the door closed. The vertical
position of the latch hook should be adjusted so that the
stop switch and the monitored latch switch are activated
with the door closed.

4. Secure the screws firmly.
5. Check the operation of all switches. If each switch has

not activated with the door closed, loosen screw and
adjust the latch hook position.

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

when in the latched position. First check upper position
of latch hook, pushing and pulling upper portion of door
toward the oven face. Then check lower portion of the
latch hook,  pushing and pulling lower portion of door
toward the oven face. Both results (play in the door)
should be less than 0.5mm.

2. The monitored latch switch and stop switch interrupt the

circuit before the door can be opened.

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

door is opened.

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

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

Latch hook

Tab

SW3: Stop switch 

SW2: Monitor switch 

SW1:  Monitored latch switch 

Tab

Tab

Latch hook

SW3: Stop switch

Door

SW2: Monitor switch

SW1: Monitored latch switch

Latch heads

“Test Procedure”, and Adjustment Procedure below.

R-244M - 15

REMOVAL
1. Disconnect the power supply cord.
2. Open the door slightly.
3. Remove the choke cover taking care not to break clips

by inserting an  iron plate (thickness of about 0.5mm) or
flat type screw driver to the gap between the choke
cover and door panel as shown Figure C-4 to free the
engaged parts.

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

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

upper and lower oven hinges by lifting up.

7. 1. Remove door assy by removing screws (4).
8. Release door panel from tabs of door frame and remove

door frame by sliding the door panel downward.

9. Now, door panel with inner sealer film is free.
10. Tear inner sealer film from door panel.
11. Now, door panel is free.
12. Slide latch head upward and remove it from door frame

with releasing latch spring from door frame and latch
head.

13. Now, latch head and latch spring are free.
14. Remove Glass Stopper Screw (noting position of

15.Slide glass towards Glass Stopper position and

16. Lift upper edge of glass, which will now be free from

17.Refitting is a reversal of the above when refitting,

RE-INSTALL
1. Re-install the outer door glass to the door frame with the

glass stopper.

2. Hold the glass stopper with the one (1) screw.
3. Re-install latch spring to the head. Re-install latch spring

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

4. Re-install door panel to door frame by fitting tabs of door

frame to holes of door panel.

5. Put sealer film on door panel. Refer to “Inner Sealer

Film” and figure C-6, on how to handle the new film.

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

and lower oven hinges.

7. Re-install choke cover  to door panel by pushing.
Note: After any service to the door;
(A) Make sure that monitored latch switch, stop switch

1. Door latch heads smoothly catch latch hook through

latch holes and that latch head goes through center of
latch hole.

2. Deviation of door alignment from horizontal line of

cavity face plate is to be less than 1.0mm.

3. Door is positioned with its face pressed toward cavity

face plate.

4. Check for microwave leakage around door with an

approved microwave survey meter.  (Refer to Microwave
Measurement Procedure.)

Note:

The door on a microwave oven is designed to
act as an electronic seal preventing the leakage
of microwave energy from oven cavity during
cook cycle. This function does not require that
door be air-tight, moisture (condensation)-tight
or light-tight. Therefore, occasional appearance
of moisture, light or sensing of gentle warm air
movement around oven door is not abnormal
and do not of themselves, indicate a leakage of
microwave energy from oven cavity.

Installation
1. Tear away the backing film.
3. Put the pasted side of the inner sealer film on the door

panel.

10

5

4

12

8

7

9

11

3

2

1

Choke Cover

Door Frame

Putty Knife

6

Pin

Pin

Lower
Oven
Hinge

Lower Oven
Hinge

Upper
Oven
Hinge

Upper Oven
Hinge

Door Panel

Choke Cover

Slit Choke

Door film

Finger tab

Backing film

16

R-244M -

After any repair, the microwave oven must be checked for microwave leakage to ensure continued safe operation. BS EN 60335-
2-25 specifies that the maximum permitted leakage with a load of 275 ml is 50 W/m

2 

(equivalent to 5 mW/cm

2) 

at  a distance of

5 cm from the oven.

The following items are required to carry out this test:-
1.  A low form of 600 ml beaker made from an electrically non-conductive material, such as glass or plastic, with an inside

diameter of approximately 8.5 cm. This must contain 275 

±

 15 ml of water, at an initial temperature of 20 

±

 2˚C.

2. A leakage detector which has been calibrated within the preceding 12 months to a standard whose accuracy  can be traced

to National Physical Laboratory Standards.

Recommended instruments are:

Apollo “XI”
Celtec “A100”

Before commencing the test, check that the leakage detector is functioning and adjusted according to the manufacturer’s
instructions, and any spacers are fitted to ensure that measurement is taken 5cm from the surface of the oven.

1. Place the beaker containing the water load in the oven cavity at the centre of the turntable. The placing of this standard load

in the oven is important, not only to protect the oven, but also to ensure that any leakage it is not disguised by too large a
load absorbing energy.

2. Close the oven door, and with the power level set to FULL, turn the oven ON with the timer set for a few minutes operation.

Should the water begin to boil before the test has been completed, it should be replaced.

3. As shown in the diagram below, move the probe slowly (not faster than 2.5 cm/sec.);-
a) around the edge of the door following the gap
b) across the face of the door
c) across any vents in the oven’s sides, rear or top

Dotted line indicates the path by the leakage detector.

Whilst the maximum leakage permitted in BS60335 2-25 is 50 /W/m 

2

(equivalent to 5 W/cm

2

),it is not normal to detect any

significant leakage, and therefore any detected leakage should be investigated.