MICROWAVE OVEN M1714R SERVICE Manual MICROWAVE OVEN CONTENTS 1. Precaution 2. Specifications 3. Operating Instructions 4. Disassembly and Reassembly 450 300 600 700 850W 100 0 5. Alignment and Adjustments 1 2 3 35 30 4 25 5 20 6 15 7 10 9 6. Troubleshooting 8 7. Exploded Views and Parts List 8.
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.
1. Precaution Follow these special safety precautions. Although the microwave oven is completely safe during ordinary use, repair work can be extremely hazardous due to possible exposure to microwave radiation, as well as potentially lethal high voltages and currents. 1-1 Safety precautions ( ) 1. All repairs should be done in accordance with the procedures described in this manual. This product complies with Federal Performance Standard 21 CFR Subchapter J (DHHS). 2.
Pretaution 1-2 Special Servicing Precautions (Continued) 17. When checking the continuity of the witches or transformer, always make sure that the power is OFF, and one of the lead wires is disconnected. 18. Components that are critical for safety are indicated in the circuit diagram by shading, or . 19. Use replacement components that have the same ratings, especially for flame resistance and dielectric strength specifications.
2.
3.
4. Disassembly and Reassembly 4-1 Replacement of Magnetron, Motor Assembly and Lamp Remove the magnetron including the shield case, permanent magnet, choke coils and capacitors (all of which are contained in one assembly). Cover Air Thermo S/W Lamp 1. Disconnect all lead wires from the magnetron and lamp. 2. Remove a screw securing the magnetron supporter. 3. Remove the magnetron supporter. 4. Remove the air cover. 5. Remove screws securing the magnetron to the wave guide. 6.
Disassembly and Reassembly 4-3 Replacement of Door Assembly 4-3-1 Removal of Door Assembly Remove hex bolts securing the upper hinge and lower hinge. Then remove the door assembly. Upper Hinge Screws Lower Hinge Screw 4-3-2 Removal of Door "C" Insert flat screwdriver into the gap between Door "E" and Door "C" to remove Door "C". Be careful when handling Door "C" because it is fragile.
Disassembly and Reassembly 4-3-5 Reassembly Test After replacement of the defective component parts of the door, reassemble it and follow the instructions below for proper installation and adjustment so as to prevent an excessive microwave leakage. 1. When mounting the door to the oven, be sure to adjust the door parallel to the bottom line of the oven face plate by moving the upper hinge and lower hinge in the direction necessary for proper alignment. 2.
Disassembly and Reassembly 4-6 Replacement of Control Circuit Board 4-6-1 Removal of Ass'y Control Box 1. Disconnect the connectors from the control box assembly. 2. Remove screws securing the control box assembly. 3.Remove the knobs of the control box Ass'y. SCREW 4. Remove the screw securing the timer.
5. Alignment and Adjustments PRECAUTION 1. High voltage is present at the high voltage terminals during any cook cycle. 2. It is neither necessary nor advisable to attempt measurement of the high voltage. 3. Before touching any oven components or wiring, always unplug the oven from its power source and discharge the high voltage capacitor. 5-1 High Voltage Transformer 1. Remove connectors from the transformer terminals and check continuity. 2.
Alignment and Adjustments 5-4 High Voltage Capacitor 1. Check continuity of the capacitor with the meter set at the highest resistance scale. 2. Once the capacitor is charged, a normal capacitor shows continuity for a short time, and then indicates 9MW. 3. A shorted capacitor will show continuous continuity. 4. An open capacitor will show constant 9MW. 5. Resistance between each terminal and chassis should read infinite. 5-5 High Voltage Diode 1.
Alignment and Adjustments 5-8 Output Power of Magnetron CAUTION MICROWAVE RADIATION PERSONNEL SHOULD NOT ALLOW EXPOSURE TO MICROWAVE RADIATION FROM MICROWAVE GENERATOR OR OTHER PARTS CONDUCTING MICROWAVE ENERGY. The output power of the magnetron can be measured by performing a water temperature rise test. Equipment needed : * Two 1-liter cylindrical borosilicate glass vessel (Outside diameter 190 mm) * One glass thermometer with mercury column NOTE: Check line voltage under load.
Alignment and Adjustments 5-10 Procedure for Measurement of Microwave Energy Leakage 1) Pour 275±15cc of 20±5ûC(68±9ûF) water in a beaker which is graduated to 600cc, and place the beaker in the center of the oven. 2) Start to operate the oven and measure the leakage by using a microwave energy survey meter. 3) Set survey meter with dual ranges to 2,450MHz. 4) When measuring the leakage, always use the 2 inch spacer cone with the probe. Hold the probe perpendicular to the cabinet door.
6. Troubleshooting WARNING FOR HIGH VOLTAGE 4000 VOLTS EXIST AT THE HIGH VOLTAGE AREA. DO NOT OPERATE THE OVEN WITH CABINET PARTS REMOVED. DO NOT REMOVE THE CABINET PARTS IF THE POWER SUPPLY CORD IS PLUGGED IN THE WALL OUTLET. UNPLUG THE POWER CORD BEFORE SERVICING. 6-1 Electrical Malfunction Parts Fuse blows out when door is opened. Fuse is open. Oven lamp does not light. Fan does not operate. Cause Diagnosis Remedy Defective primary interlock switch ary winding.
Troubleshooting 6-1 Electrical Malfunction (Continved) Parts Cause Diagnosis Remedy 1) Too small a load If a small amount of food is heated for a long time, period of microwave may turn off during operation. To increase the oven load, add a glass of water into the oven. 2) Defective magnetron thermal cutout S/W Check to see if the magnetron thermal cutout switch is activated at a temperature higher than 150˚C. Replace thermal cutout switch. Electric shock is felt.
Troubleshooting 6-2 Unsatisfactory Cooking Parts - Food is not heated. Cause Diagnosis Remedy 1) Open cathode of magnetron Check the terminals with a multimeter to see if the heater circuit is open. Replace magnetron. 2) Defective H. V. Diode Check the H. V. Diode for continuity in the reverse and normal directions using megger. If there is continuity in the reverse direction, the H. V. Diode may be faulty. (In this event H. V. Capacitor will be hot) Replace H. V. Diode.
7.
Exploded Views and Parts List 7-2 Main Parts List Ref. No. Parts No. M1 M2 M3 M4 M5 M6 M7 M8 M9 M10 M11 M12 DE70-30116W DE39-20145A DE39-00053A DE96-00008A DE71-60467A DE96-00031A DE47-20009A DE03-30029A DE93-20020A 4713-001004 DE74-20102B DE92-90436C PANEL-OUTER;SECC,T0.5,W351.7,L1014.7,WHT,M ASSY POWER CORD;MOONSUNG,-,230V50Hz,-,-,-,M308 WIRE HARNESS-A;230V50HZ,3RD FISH2-D TYPE,-,M1714/XEF ASSY NOISE FILTER;SN-3WEB,250V10A,3W INRUSH D COVER-BLOWER;PP,-,-,-,-,3RD-0.
Exploded Views and Parts List 7-3 Door Parts List Ref. No. Parts No. D1 D2 D3 D4 D5 D6 D7 D8 D9 D10 DE64-20116B DE01-00099A DE64-40277B DE64-40278K DE94-00124C DE64-40264C DE61-70033A DE61-80005A DE61-80004A DE94-00202F Description / Specification HANDLE-DOOR;ABS,-,-,-,P/WHT,M1774,3RD-FISH2 FILM-DOOR;PET,T0.13,W23,L177.
Exploded Views and Parts List 7-6 Standard Parts List Parts No.
8.
