R21LTF
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R21LTF
Service Manual
CHAPTER 1.
WARNING TO SERVICE PERSONNEL
Microwave ovens contain circuitry capable of producing very high voltage and current, contact with following parts may result in a severe, possibly
fatal, electrical shock.
(Example)
High Voltage Capacitor, High Voltage Power Transformer, Magnetron, High Voltage Rectifier Assembly, High Voltage Harness etc..
Read the Service Manual carefully and follow all instructions.
[1] Before Servicing
1. Disconnect the power supply cord
, and then remove outer
case.
2. Open the door and block it open.
3. Discharge high voltage capacitor.
WARNING:
RISK OF ELECTRIC SHOCK. DISCHARGE THE HIGH-
VOLTAGE CAPACITOR BEFORE SERVICING.
The high-voltage capacitor remains charged about 60 seconds after
the oven has been switched off. Wait for 60 seconds and then short-
circuit the connection of the high-voltage capacitor (that is the connect-
ing lead of the high-voltage rectifier) against the chassis with the use
of an insulated screwdriver.
Whenever troubleshooting is performed the power supply must be
disconnected. It may, in some cases, be necessary to connect the
power supply after the outer case has been removed, in this event,
1) Disconnect the power supply cord, and then remove outer case.
2) Open the door and block it open.
3) Discharge high voltage capacitor.
4) Disconnect the leads to the primary of the power transformer.
5) Ensure that the leads remain isolated from other components and
oven chassis by using insulation tape.
6) After that procedure, reconnect the power supply cord.
[2] When the testing is completed,
1. Disconnect the power supply cord, and then remove outer case.
2. Open the door and block it open.
3. Discharge high voltage capacitor.
4. Reconnect the leads to the primary of the power transformer.
5. Reinstall the outer case (cabinet).
6. Reconnect the power supply cord after the outer case is installed.
7. Run the oven and check all functions.
[3] After repairing
1. Reconnect all leads removed from components during testing.
2. Reinstall the outer case (cabinet).
3. Reconnect the power supply cord after the outer case is installed.
4. Run the oven and check all functions.
Microwave ovens should not be run empty. To test for the presence of
microwave energy within a cavity, place a cup of cold water on the
oven turntable, close the door and set the power to HIGH and set the
microwave timer for two (2) minutes. When the two minutes has
elapsed (timer at zero) carefully check that the water is now hot. If the
water remains cold carry out
Before Servicing
procedure and re-
examine the connections to the component being tested.
When all service work is completed and the oven is fully assembled,
the microwave power output should be checked and microwave leak-
age test should be carried out.
Don't Touch !
Danger High Voltage
