MICROWAVE OVEN SERVICE MANUAL

1 MICROWAVE OVENSERVICE MANUALMODEL: MV1526W CAUTIONBEFORE SERVICING THE UNIT, READ THESAFETY PRECAUTIONS IN THIS MANUAL . MV1526 Bwebsite PRECAUTIONSPRECAUTIONS TO BE OBSERVED BEFORE ANDDURING SERVICING TO AVOID POSSIBLE EXPOSURETO EXCESSIVE MICROWAVE ENERGYa. Do not operate or allow the oven to be operated with the door Make the following safety checks on all ovens to be serviced before activating themagnetron or other MICROWAVE source, and make repairs as necessary; (1) Interlockoperation, (2) proper door closing, (3) seal and sealing surfaces (arcing, wear, andother damage), (4) damage to or loosening of hinges and latches, (5) evidence ofdropping or Before turning on MICROWAVE power for any SERVICE test or inspection within themicrowave generating compartments, check the magnetron, wave guide ortransmission line, and cavity for proper alignment, integrity, and Any defective or misadjusted components in the interlock, monitor, door seal, andmicrowave generation and transmission systems shall be repaired, replaced, oradjusted by procedures described in this MANUAL before the oven is released to A MICROWAVE leakage check to verify compliance with the CSA Standard should beperformed on each oven prior to release to the owner.

2 Proper operation of the MICROWAVE ovens requires that the magnetron be assembled to thewave guide and cavity. Never operate the magnetron unless it is properly installed. Be sure that the magnetron gasket is properly installed around the dome of the tube wheneverinstalling the magnetron. Routine SERVICE safety procedures should be exercised at all times. Untrained personnel should not attempt SERVICE without a thorough review of the testprocedures and safety information contained in this this MANUAL carefully. Failure to adhere to or observe the information in this MANUAL may result in exposingyourself to the MICROWAVE Energy normally contained within the oven OF CONTENTS(Page)SAFETY PRECAUTIONS ..Inside front page SPECIFICATIONS ..1-1 CAUTIONS ..2-1 INSTALLATION ..3-1 OPERATING CONTROL PANEL ..4-1 CONTROL PANEL INSTRUCTIONS ..4-2 OVERALL CIRCUIT DIAGRAM.

3 5-1 SCHEMATIC MATRIX CIRCUIT FOR TOUCH KEY BOARD ..5-2 GENERAL INFORMATION FOR SERVICE ..6-1 GENERAL PRECAUTIONS IN USE ..6-1 TRIAL OPERATION ..6-1 FEATURES AND SPECIFICATIONS SERVICE INFORMATION ..7-1 PRECAUTIONS AND REPAIR SERVICE TIPS ..7-1 MICROWAVE LEAKAGE TEST ..7-2 POWER OUTPUT MEASUREMENT ..7-3 DISASSEMBLY INSTRUCTIONS ..7-4 INTERLOCK SYSTEM .. 7-12 INTERLOCK CONTINUITY TEST .. 7-14 TEST AND CHECKOUT PROCEDURES AND TROUBLE 7-15A. TEST 7-15B. CHECKOUT 7-18C. TROUBLE SHOOTING .. 7-21 EXPLODED VIEW ..8-1 REPLACEMENT PARTS LIST ..8-8 SCHEMATIC DIAGRAM OF PCB .. 8-12 PRINTED CIRCUIT BOARD .. 8-13 PCB PARTS 8-141-1 Rated Power ,500W maximum ( MICROWAVE oven+Cook top lamps+Ventilation fan) MICROWAVE ,000W (IEC 60705)Adjustable 100W through 1000W, 10 stepsFrequency ..2,450 MHz 50 MHzPower VAC, 60 HzRated Current.

4 13 Amp. ( MICROWAVE oven+Cook top lamps+Ventilation fan)Magnetron Cooling ..Forced Air Voltage Double Half-WaveDoor Sealing ..Choke SystemSafety Cavity Thermostat:Open at 90 C 5 C Fuse(20A)Primary Interlock SwitchSecondary Interlock SwitchInterlock MonitorMagnetron ..2M214-39 FHigh Voltage Capacitor ..Capacitor: F, KV ACHigh Voltage ; 350mA, KV Cook top Lamp ..125 V, 30 W Cavity Lamp ..125 V, 30 WTimer ..Digital, up to 99 mim. 99 sec. (in each cooking stage)Tray ..Tempered Safety GlassOverall Dimensions ..2915/16 (W)x167/16 (D)x153/8 (H)Oven Cavity Size ..197/8 (W)x143/16 (D)x815/16 (H)Effective Capacity of Oven Cavity .. s MANUAL & Cooking Guide, Installation MANUAL ,Exhaust Adapter, Exhaust Damper, Mounting Kit and Two Filters,Rotating Ring DO NOT operate on a 2-wire extension cord duringrepair and use. NEVER TOUCH any oven components or wiring duringoperation.

5 BEFORE TOUCHING any parts of the oven, alwaysremove the power plug from the outlet. For about 30 seconds after the oven stops, an electriccharge remains in the high voltage capacitor. Whenreplacing or checking, you must discharge the highvoltage capacitor by shorting across the two terminalswith an insulated screwdriver. Remove your watch whenever working close to orreplacing the Magnetron. DO NOT touch any parts of the control panel circuit. Aresulting static electric discharge may damage NEVER operate the oven with no load. NEVER injure the door seal and front plate of the ovencavity. NEVER put iron tools on the magnetron. NEVER put anything into the latch hole and the interlockswitches area. Proper operation of the MICROWAVE oven requires thatthe magnetron be assembled to the waveguide andcavity. Never operate the magnetron unless it isproperly installed.

6 Be sure that the magnetron gasket is properlyinstalled around the dome of the tube wheneverinstalling the other appliances, the MICROWAVE oven ishigh-voltage and high-current it is free from danger in ordinary use,extreme care should be taken during OVEN IS TO BE SERVICED ONLYBY PROPERLY QUALIFIED RADIATIONP ersonnel should not be exposed to themicrowave energy which may radiate from themagnetron or other MICROWAVE generatingdevice if it is improperly used or input and output MICROWAVE connections,waveguide, flange, and gasket must be operate the device without a microwaveenergy absorbing load look into an open waveguide or antennawhile the device is FINMAGNETRONCHASSIS GROUNDFILAMENTTERMINALSMAGNETRON3-1 INSTALLATIONPRECAUTIONS ON INSTALLATIONA. Plug the power supply cord into a 120V AC, 60Hz,single-phase power source with a capacity of 15 Aor Avoid placing the unit in a location where there isdirect heat or splashing Install the unit on the mounting plate Place the unit as far away as possible from TV, radio, etc.

7 To prevent INSTRUCTIONSFor personal safety, this appliance must be fullygrounded at all the event of an electrical short circuit, groundingreduces the risk of electrical plug must be plugged into an outlet that isproperly installed and YOU BEGIN, READ THE FOLLOWING INSTRUCTIONS COMPLETELY AND use of the grounding plug can result in arisk of electric not, under any circumstances, cut or remove thethird ground prong from the power cord unit is equipped with a 3-prong plug for yoursafety. If the wall outlet is a grounded 3-hole type,the unit will be grounded with GroundProngProperly Polarizedand GroundedOutletCONTROL PANEL4-1 OPERATING INSTRUCTIONS1247101316211836581214171915 20911 CONTROL PANEL INSTRUCTIONS4-21. DISPLAY:The Display includes a clock and indicators totell you time of day, cooking time settings and cookingfunctions POPCORN: Touch this pad when popping popcorn inyour MICROWAVE POTATO: Touch this pad to cook potatoes from 1 to BEVERAGE:Touch this pad to reheat one cup or twocups a PIZZA: Touch this pad to reheat 1 to 3 TIME DEFROST:Touch this pad to defrost most otherfrozen FROZEN ENTREE:Touch this pad to cook frozen entreesby choosing a preset AUTO COOK:Touch this pad to cook vegetables, rice, AUTO REHEAT:Touch this pad to reheat dinner plate,soup/sauce, casserole, AUTO DEFROST:Meat, poultry, fish.

8 Touch on pad toselect food type and defrost food by NUMBER: Touch number pads to enter cooking time,power level, quantities or TIME COOK:Touch this pad to set a cooking POWER LEVEL:Touch this pad to select a cookingpower CUSTOM SET:Touch this pad to change the oven sdefault settings for sound, clock, display speed, defrostweight, and demo mode KITCHEN TIMER:Touch this pad to set the CLOCK:Touch this pad to enter the time of FAN HI/LO/OFF:Touch this pad to turn the fan on or LIGHT HI/LO/OFF:Touch this pad to turn on thecooktop/countertop STOP/CLEAR: Touch this pad to stop the oven or clearall EZ ON:Touch this pad to set and start quickly at 100%power START:Touch this pad to start a function. If you openthe door after oven begins to cook, retouch DIAGRAMOVERALL CIRCUIT DIAGRAMMATRIX CIRCUIT FOR TOUCH KEY BOARDCUSTOM OnCLOCKSTOP/CLEARTIMEDEFROSTAUTODEFROSTA UTOREHEAT5-26-1 GENERAL PRECAUTIONS IN USEA.

9 Never operate the unit when it is the oven with no load may shorten thelife of the magnetron. Whenever cooking dry foods(dried fish, bread, etc.) or a small amount of food,be sure to put a glass of water into the cookingcompartment. The glass turntable may become hotafter operating, be careful when touching Aluminum foil should be avoided because it will disrupt cooking and may cause arcing. However, small pieces may be used to cover some parts offood to slow the cooking. Any aluminum foil usedshould never be closer than cm to any side wallof the OPERATIONA fter installation, the following sequences and results should be checked Put a container filled with water (about 1 liter) intothe oven, and close the door Set cooking time for 10 minutes by touching 1 and then 0 three times. 1, 0, 0, 0 appears in the display Touch the START sure the cavity light comes on.

10 The unit will begin cooking and the display window will show thetime counting down by After about 5 minutes, make sure the primaryinterlock switch, the secondary interlock switch andthe interlock monitor switch operate properly byopening and closing the door several times. Touchthe START key each time the door is Continue operating the unit. Four long beep soundsignal is heard when the time is up. The unit willshut off Confirm the water is Finally, measure the output power according to POWER OUTPUT MEASUREMENT onpage AND SPECIFICATIONSFEATURESA. The safety systems incorporated in this model are:(1) Primary interlock switch(2) Secondary interlock switch(3) Interlock monitor switch(4) Choke system(5) Magnetron thermal fuse(6) Oven cavity thermostat(Note: This thermostat located on the ovencavity will open and stop the unit from operationonly if a high temperature is reached, such as,a fire created by overcooking food.)