Sharp R-231NW Service Manual - Page 25

R-231NW [2] OUTER CASE REMOVAL To remove the outer case, procedure as follows. 1. Disconnect the power supply cord. 2. Open the oven door and block it open. 3. Remove the two (2) screws from the lower portion of the rear cabinet using a T20H Torx type or GTXH20-100 screw driver. 4. Remove the remaining three (3) screws from the upper portion of the rear and two (2) screws along the right side of outer case. 5. Slide the entire outer case back out about 1 inch (3 cm) to free it from retaining clips on the cavity face plate. 6. Lift entire outer case from the unit. CAUTION: DISCONNECT OVEN FROM POWER SUPPLY BEFORE REMOVING OUTER CASE. DISCHARGE THE HIGH VOLTAGE CAPACITOR BEFORE TOUCHING ANY OVEN COMPONENTS OR WIRING. NOTE: When replacing the outer case, the 2 special Torx screws must be reinstalled in the same locations. [3] MAGNETRON REMOVAL 1. Disconnect the power supply cord and remove outer case. 2. Open the oven door and block it open. 3. Discharge high voltage capacitor. 4. Remove the two (2) screws holding the air duct to the oven cavity. 5. Release the air duct from the oven cavity. 6. Disconnect the wire leads from magnetron. Special screw Screw Driver (Type: TORX T20 H or GTXH20-100) 7. Remove the four (4) screws holding the magnetron to the waveguide. 8. Remove the magnetron from waveguide. 9. Now, the magnetron is free. CAUTION: WHEN REPLACING THE MAGNETRON, BE SURE THE R.F. GASKET IS IN PLACE AND THE MAGNETRON MOUNTING SCREWS ARE TIGHTENED SECURELY. [4] HIGH VOLTAGE COMPONENTS REMOVAL (HIGH VOLTAGE CAPACITOR AND HIGH VOLTAGE RECTIFIER ASSEMBLY) To remove the components, proceed as follows. 1. Disconnect the power supply cord and remove outer case. 2. Open the oven door and block it open. 3. Discharge high voltage capacitor. 4. Disconnect the high voltage wire (white) of the power transforme from high voltage capacitor. 5. Disconnect the H.V. wire of the H.V. rectifier assembly from the magnetron. 6. Disconnect the filament lead (red) of the power transformer from the H.V. capacitor. 7. Remove one (1) screw holding capacitor holder to bottom plate. 8. Remove one (1) screw holding ground side terminal of high voltage rectifier assembly, and remove capacitor holder. 9. Disconnect the terminal of high voltage rectifier assembly from high voltage capacitor. 10. Now the H.V. rectifier assembly and H.V. capacitor should be free. CAUTION: WHEN REPLACING HIGH VOLTAGE RECTIFIER ASSEMBLY, ENSURE THAT THE CATHODE (GROUND) CONNECTION IS SECURELY FIXED TO THE CAPACITOR HOLDER WITH A GROUNDING SCREW. CAUTION: D O N O T R E P L A C E O N LY H I G H V O LTA G E RECTIFIER. WHEN REPLACING IT, REPLACE HIGH VOLTAGE RECTIFIER ASSEMBLY. [5] POWER TRANSFORMER REMOVAL 1. REMOVAL 1. Disconnect the power supply cord and remove outer case. 2. Open the oven door and block it open. 3. Discharge high voltage capacitor. 4. Disconnect the wire leads (main wire harness) from power transformer. 5. Disconnect the filament lead (red) of the power transformer from magnetron. 6. Disconnect the leads of the power transformer from high voltage capacitor. 7. Remove the four (4) screws holding the transformer to bottom plate from the upper side and bottom side. 8. Remove the transformer. 9. Now the power transformer is free. 2. REINSTALL 1. Rest transformer on the bottom plate with its primary terminals toward the oven face plate. 2. Secure transformer with four (4) screws to the bottom plate (two screws from upper side and two screws from bottom side). 3. Re-connect wire leads (primary and high voltage) and filament leads to the power transformer, magnetron and high voltage capacitor, referring to "Pictorial Diagram". 4. Re-install outer case and check that the oven is operating properly. 11 - 2