TECHNICAL FLASH T.F. 22-432 Department 731A Toronto BASIC SERVICE MANUAL MICROWAVE OVEN MODEL 767. 8703000 767. 8803000 767. 8903000 767. 8903400 767. 8903900 APRIL, 2000...
SAFETY PRECAUTIONS This device is to be serviced only by properly qualified service personnel. Consult the service manual for proper service procedures to assure continued safety operation and for precautions to be taken to avoid possible exposure to excessive microwave energy. PRECAUTIONS TO BE OBSERVED BEFORE AND DURING SERVICING TO AVOID POSSIBLE EXPOSURE TO EXCESSIVE MICROWAVE ENERGY...
SPECIFICATIONS MODEL NO. 87030 88030 89030/89034/89039 Rated Power Consumption 1,500 W Output 1,100 W (*IEC 705 Rating standard) Frequency 2,450 MHz Power Supply 120 V AC, 60 Hz Magnetron Cooling Forced Air Cooling Microwave Stirring Turntable Rectification Rectification Voltage Doubler Half-Wave Door Sealing Choke Cover and Choke System Safety Devices...
CAUTIONS Unlike other appliances, the microwave oven is MICROWAVE RADIATION high-voltage and high-current equipment. Personnel should not be exposed to the Though it is free from danger in ordinary use, microwave energy which may radiate from the extreme care should be taken during repair. magnetron or other microwave generating device if it is improperly used or connection.
INSTALLATIONS BEFORE YOU BEGIN, READ THE FOLLOWING INSTRUCTIONS COMPLETELY AND CAREFULLY. INSTALLING GROUNDING INSTRUCTIONS 1. Empty the microwave oven and clean inside it with For personal safety, this appliance must be fully a soft, damp cloth. Check for damage such as grounded at all times.
OPERATING INSTRUCTIONS FEATURES Oven Front Plate Window Door Screen Door Seal Display Window Control Panel Door Open Button Safety Door Lock System Turntable Rotating Ring CONTROL PANEL 1. INDICATORS 2. DISPLAY WINDOW 3. QUICK SENSOR 4. QUICK TOUCH COOK 5 QUICK ON 6.
CIRCUIT DESCRIPTION • A high voltage of approximately 2100 volts AC is GENERAL DETAILS generated in the secondary of the high voltage • The low voltage transformer supplies the necessary transformer which is increased by the action of the high voltage to the micom controller when power cord is voltage diode and charging of the high voltage plugged in.
SERVICE INFORMATION TOOLS AND MEASURING INSTRUMENTS NECESSARY TOOLS NECESSARY MEASURING INSTRUMENTS Tools normally used for TV servicing are sufficient. • TESTER (VOLTS-DC, AC, Ohmmeter) Standard tools are listed below. • Microwave survey meter • Diagonal pliers - Holaday HI-1500 • Long nose pliers HI-1501 •...
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MEASUREMENT WITH OUTER CASE NOTES WHEN MEASURING REMOVED • Do not exceed meter full scale deflection. • The test probe must be removed no faster than • When you replace the magnetron, measure for 1 inch/sec (2.5 cm/sec) along the shaded area, microwave energy leakage before the outer case is otherwise a false reading may result.
MEASUREMENT OF MICROWAVE POWER OUTPUT • Microwave power output measurement is made with • The microwave power output P in watts is calculated the microwave oven supplied at its rated voltage and from the following formula : operated at its maximum microwave power setting with 4187 x (∆T) a load of (1000±5) g of potable water.
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D. PCB ASSEMBLY REMOVAL Remove choke cover cap(For model 87030/88030) 1) Remove the control panel assembly from the cavity. (Refer to control panel assembly removal on previous page.) 2) Remove screws which hold the PCB SUB ASS’Y to the control panel. 3) Disconnect the flat cable from the PCB SUB ASS’Y and take off the PCB SUB ASS’Y Control Panel...
F. AIR DUCT ASSEMBLY REMOVAL I. FAN MOTOR ASSEMBLY REMOVAL 1) Discharge the high voltage capacitor. 1) Disconnect the leadwire from lamp and MGT thermostat. 2) Remove the mounting screw to the magnetron. 2) Disconnect the leadwire from fan motor, noise filter and high voltage capacitor.
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K. REMOVING THE TURNTABLE MOTOR M. INTERLOCK SYSTEM 1) Remove the glass turntable. 1) INTERLOCK MECHANISM 2) Remove the rotating ring assʼy by hand. The door lock mechanism is a device which has 3) Remove the turntable motor cover. been specially designed to eliminate completely The turntable base cover is easily removed by microwave activity when the door is opened during pinching the six parts with wire cutting pliers.
INTERLOCK CONTINUITY TEST 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 B.
COMPONENT TEST PROCEDURE 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.
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COMPONENTS TEST PROCEDURE RESULTS Antenna Gasket Chassis Filament 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. HIGH VOLTAGE Measure the resistance. Normal: Momentarily indicates CAPACITOR (Ohm-meter scale: Rx1000) several ohms, and...
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COMPONENTS TEST PROCEDURE RESULTS Check for continuity of relay 2 with an RELAY 2 POWER ohm-meter. LEVEL (Remove wire leads from relay 2 and operate the unit.) 4 sec 18 sec 6 sec 16 sec 8 sec 14 sec 10 sec 12 sec 12 sec 10 sec...
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.
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(TROUBLE 1) The following visual conditions indicate a probable defective control circuit. 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.
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(TROUBLE 2) Oven does not operate at all, Display window does not display any figures, and no input is accepted. CONDITION CHECK RESULT CAUSE REMEDY Malfunction of the Replace fuse, Check continuity 1. Fuse blows. Continuity. monitor switch. primary, monitor, of monitor secondary switch (with...
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(TROUBLE 3) Display shows all figures set, but oven does not start cooking while desired program times are set and START pad is touched. CONDITION CHECK RESULT CAUSE REMEDY Defective Replace Check continuity 1. Setting time No continuity. secondary switch. secondary switch.
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(TROUBLE 5) No microwave oscillation even though oven lamp and fan motor run. (Display operates properly) CONDITION CHECK RESULT CAUSE REMEDY No microwave Defective PCB Replace PCB Disconnect the No continuity. oscillation. assembly. assembly. wire leads from relay 2 and check continuity Continuity.