Summary of the content on the page No. 1
DMOC205SS
VMOC205SS
SERVICE MANUAL
S14M227DMO205
MICROWAVE OVEN
DMOC205SS
MODELS
VMOC205SS
(VMOC205SS model shown)
In the interest of user-safety the oven should be restored to its original condition and only parts identical to those specified
should be used.
WARNING TO SERVICE PERSONNEL: Microwave ovens contain circuitry capable of producing very high voltage and
current. Contact with the following parts may result in a severe, possibly fatal, electrical shock. (Inverter unit that includes
High
Summary of the content on the page No. 2
DMOC205SS VMOC205SS 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. (b) Make the following safety checks on all ovens to be serviced before activating the magnetron or other microwave source, and make repairs as necessary: (1) interlock operation, (2) proper door closing, (3) seal and sealing surfaces (arcing, wear, and other damage), (4) damage to or loosening
Summary of the content on the page No. 3
DMOC205SS VMOC205SS Notes 1
Summary of the content on the page No. 4
DMOC205SS VMOC205SS WARNING TO SERVICE PERSONNEL Microwave ovens contain circuitry capable of pro- ducing 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. Don't Touch ! Danger High Voltage outer case. Before Servicing 2. Open the
Summary of the content on the page No. 5
DMOC205SS VMOC205SS MICROWAVE MEASUREMENT PROCEDURE (CANADA) After adjustment of the door switches are completed individually or collectively, switch test and microwave leakage test must be performed with survey instrument and test result must be confirmed to meet the requirement of the performance standard for microwave ovens as undermentioned. A. Requirements: Every microwave oven shall function in such a manner that when the oven is fully assembled and operating with its service controls and
Summary of the content on the page No. 6
DMOC205SS VMOC205SS MICROWAVE MEASUREMENT PROCEDURE (USA) A. Requirements: 1) Microwave leakage limit (Power density limit): The power density of microwave radiation emitted by a microwave oven 2 should not exceed 1mW/cm at any point 5cm or more from the external surface of the oven, measured prior to acquisition 2 by a purchaser, and thereafter (through the useful life of the oven), 5 mW/cm at any point 5cm or more from the external surface of the oven. 2) Safety interlock switches: Primary int
Summary of the content on the page No. 7
DMOC205SS VMOC205SS SERVICE MANUAL VIKING RANGE CORPORATION PRODUCT DESCRIPTION MICROWAVE OVENS DMOC205SS VMOC205SS GENERAL INFORMATION FOREWORD OPERATION This Manual has been prepared to provide Viking Service Personnel with Operation and Service Information for the Viking Microwave Ovens, DMOC205SS, VMOC205SS. TROUBLESHOOTING GUIDE AND It is recommended that service personnel carefully study the entire text of TEST PROCEDURE this manual so that they will be qualified to render satisfactory cus
Summary of the content on the page No. 8
DMOC205SS VMOC205SS SPECIFICATION ITEM DESCRIPTION Power Requirements 120 Volts 13.0 Amperes (Microwave) / 13.0 Amperes (Convection) 60 Hertz / Single phase, 3 wire grounded Power Output 900 watts (IEC 705 Test Procedure) Operating frequency of 2450MHz Convection Power Output 1450 Watts Case Dimensions Width 24-5/8" Height 14-7/8" Depth 19-1/8" Cooking Cavity Dimensions (1.5 Cubic Feet ) Width 16-1/8" Height 9-5/8" Depth 16-1/8" Control Complement Touch Control System Timer (0 - 99 min. 99 s
Summary of the content on the page No. 9
DMOC205SS VMOC205SS Electrical Requirements Grounded 3-Pronged Plug The electrical requirements are a 115 -120 volt 60 Hz, AC only, Receptacle Box 15 or more amp. fused electrical supply. It is recommended that a separate circuit serving only this appliance be provided. When installing this appliance, observe all applicable codes and ordinances. A short power-supply cord is provided to reduce risks of becoming entangled in or tripping over a longer cord. Where a two-pronged wall-receptacle is e
Summary of the content on the page No. 10
DMOC205SS VMOC205SS OPERATION DESCRIPTION OF OPERATING SEQUENCE The following is a description of component functions switch are activated with the following results. The circuits to the turntable motor, the cooling fan motor, and during oven operation. the high voltage components are de-energized, the OFF CONDITION oven lamp remains on, and the digital read-out displays the time still remaining in the cook cycle when the door Closing the door activates the door sensing switch and was opened. se
Summary of the content on the page No. 11
DMOC205SS VMOC205SS first. And then program desired cooking time by touching CONVECTION COOKING CONDITION the Number pads. The LOW MIX/BAKE pad is PREHEATING CONDITION ο preprogrammed for 350 F with 10% microwave power, Program desired convection temperature by touching the while the HIGH MIX/ROAST pad is preprogrammed for CONVECTION pad and the Temperature pad. ο 300 F with 30% microwave power. When the START pad is When the START pad is touched, the following operations touched, the following
Summary of the content on the page No. 12
MICROWAVE MICROWAVE DMOC205SS VMOC205SS The sensor “senses” the vapor and its resistance increases 4. Now, the oven is in the convection cooking mode. gradually. When the resistance reaches the value set 5. When the oven temperature has reached the programmed according to the menu, supplementary cooking is started. convection temperature, the oven goes into the The time of supplementary cooking is determined by experi- programmed cooking mode. ment with each food category and inputted into the L
Summary of the content on the page No. 13
DMOC205SS VMOC205SS IMPORTANT: detected vapors and initiated a sensor cooking cycle. During sensor cooking operation, the fire sensing op- This is because the operation of the convection fan eration sequence will not begin until the AH sensor has would interfere with the AH sensor's vapor detection. SCHEMATIC DIAGRAM SCHEMATIC NOTE: CONDITION OF OVEN 1. DOOR CLOSED. 2. CLOCK APPEARS ON DISPLAY. CONV. MAGNETRON OVEN THERMAL THERMAL THERMAL NOISE FILTER CUT-OUT CUT-OUT CUT-OUT COM. A3 (RY1) A1 A5
Summary of the content on the page No. 14
DMOC205SS VMOC205SS SCHEMATIC NOTE: CONDITION OF OVEN 1. DOOR CLOSED. 2. MIX COOKING PAD TOUCHED. 3. COOKING TIME PROGRAMMED. 4. “START” PAD TOUCHED. 5. RY2 AND RY3 WILL ALTERNATELY CLOSE. DURING COOK CYCLE. CONV. MAGNETRON OVEN THERMAL THERMAL THERMAL NOISE FILTER CUT-OUT CUT-OUT CUT-OUT COM. A3 A5 (RY1) A1 N.O. TTM CM (RY1) POWER TRANSFORMER COM. A-7 (RY3) OL FM DM RY2 COM. SECONDARY (RY2) A-9 INTERLOCK RY3 N.O. CONTROL UNIT RERAY (RY2) CAPACITOR 0.94µ N.O. (RY3) E-1 E-2 E-3 E-4 E-5 E-6 F-3 F
Summary of the content on the page No. 15
DMOC205SS VMOC205SS DESCRIPTION AND FUNCTION OF COMPONENTS DOOR SENSING AND PRIMARY INTERLOCK THIRD DOOR SWITCH SWITCHES The switch is activated by the latch heads, while the door is closed. When the door is opened, the switch interrupt the The door sensing switch in the secondary interlock system circuit to the power transformer. This switch prevents power is mounted in the upper position on the latch hook, the transformer engaging and microwave when the door opened. primary interlock switch is
Summary of the content on the page No. 16
DMOC205SS VMOC205SS oven cavity by means of the convection fan which is driven 1-3. When the damper is moved to the open position by by the convection motor. It then enters the inside of the the damper cam the damper switch is closed (ON oven through the vent holes provided on the left side of the position). oven. Next, the hot air heats the food on the turntable and 1-4. The signal from damper switch is re-sensed in the leaves the oven cavity through the vent in the center of the control unit a
Summary of the content on the page No. 17
DMOC205SS VMOC205SS (SENSOR CONDITION OFF CONDITION COOKING CONDITION (MICROWAVE) (CONVECTION) COOKING) PROBLEM POSSIBLE CAUSE AND DEFECTIVE PARTS A MAGNETRON B POWER TRANSFORMER C H.V. RECTIFIER ASSEMBLY D HIGH VOLTAGE CAPACITOR E PRIMARY INTERLOCK SWITCH F SECONDARY INTERLOCK SYSTEM G MONITOR SWITCH H MONITOR FUSE E THIRD DOOR SWITCH I THERMAL CUT-OUT J CONVECTION HEATER K THERMISTOR L DAMPER MOTOR M DAMPER SWITCH P TOUCH CONTROL PANEL Q KEY UNIT R RELAY RY-1 R RELAY RY-2 R RELAY RY-3 R RELAY
Summary of the content on the page No. 18
DMOC205SS VMOC205SS TEST PROCEDURES PROCEDURE COMPONENT TEST LETTER A MAGNETRON ASSEMBLY TEST HIGH VOLTAGES ARE PRESENT DURING THE COOK CYCLE, SO EXTREME CAUTION SHOULD BE OBSERVED. DISCHARGE THE HIGH VOLTAGE CAPACITOR BEFORE TOUCHING ANY OVEN COMPONENTS OR WIRING. To test for an open filament, isolate the magnetron from the high voltage circuit. A continuity check across the magnetron filament leads should indicate less than 1 ohm. To test for a shorted magnetron, connect the ohmmeter leads bet
Summary of the content on the page No. 19
DMOC205SS VMOC205SS TEST PROCEDURES PROCEDURE COMPONENT TEST LETTER If the capacitor is open, no high voltage will be available to the magnetron. Disconnect input leads and check for short or open between the terminals using an ohmmeter. Checking with a high ohm scale, if the high voltage capacitor is normal, the meter will indicate continuity for a short time and should indicate approximately 10 MΩ once the capacitor is charged. If the above is not the case, check the capacitor with an ohmmeter
Summary of the content on the page No. 20
DMOC205SS VMOC205SS TEST PROCEDURES PROCEDURE COMPONENT TEST LETTER MAGNETRON THERMAL CUT-OUT (on the waveguide) A continuity check across the thermal cut-out terminals should indicate a closed circuit unless the ο ο temperature of the thermal cut-out reaches approximately 257 F (125 C). An open thermal cut-out indicates overheating of the magnetron. Check for restricted air flow to the magnetron through the vent holes of the oven cavity, especially the cooling duct and cooling fan. CAUTION: IF
