Brand: SHARP
Category: Home Appliances
Document Type: Parts/Service
Language: EN
Parts/Service for R-7H55
Uploaded: Nov. 21, 2025, 6:57 p.m.
Warranty Information
None
OFF CONDITION: Closing the door activates interlock switches. When plugged in, the display shows "88:88". Touch STOP/CLEAR to set programs or clock. A colon appears, and time counts up. Opening the door turns on the oven lamp.
MICROWAVE COOKING (HIGH): Enter time using number keys, touch START. Rated voltage is supplied to the power transformer, heating the magnetron filament and generating microwave energy. The energy is channeled into the cavity. When time is up, a signal sounds, and cooking components turn off. Opening the door during cooking turns on the lamp and shows remaining time.
VARIABLE POWER COOKING (HIGH, MEDIUM, LOW): Power is supplied intermittently through relays to achieve different power levels (approx. 70%, 50%, 30%, 10% of FULL Power).
CONVECTION COOKING: Preheat the oven by touching CONVECTION and temperature pads. Touch START. Relays energize, powering the oven lamp, fan, turntable, and convection motor. Heater relay is energized to reach selected temperature. After cooking, audible signal sounds, and components turn off. Cooling fan operates until cavity temperature drops. Damper opens.
MIX COOKING (LOW MIX, HIGH MIX): Enter time, select MIX, and temperature. Touch START. Oven lamp, fan, turntable, convection motor, and damper motor are energized. Heater relay energizes. Convection heater and power transformer operate alternately for convection heat and microwave energy.
EASY DEFROST: Select EASY DEFROST, enter weight. Oven cooks according to a special sequence.
AUTO COOK: Select AUTO COOK, enter food weight. Oven computes temperature, power, and time for baking, roasting, or broiling.
SENSOR COOKING: Uses SENSOR REHEAT, RICE COOK, or STEAM MENU functions. Sensor detects steam and calculates remaining time and power.
FIRE SENSING FEATURE: Stops operation if fire is detected in the oven cavity during microwave cooking.
Troubleshooting and error codes
| CONDITION | PROBLEM | MAGNETRON | POWER TRANSFORMER | H.V. RECTIFIER ASSEMBLY | HIGH VOLTAGE CAPACITOR | 1ST. LATCH SWITCH | 2ND. LATCH SWITCH | STOP SWITCH | MONITOR SWITCH | FUSE M8A | THERMAL CUT-OUT 145°C (MG.) | THERMAL CUT-OUT 95°C (FAN) | THERMAL CUT-OUT 150°C (CONV.) | FAN MOTOR | TURNTABLE MOTOR | CONVECTION MOTOR | CONVECTION HEATER | THERMISTOR | DAMPER MOTOR | DAMPER SWITCH | OVEN LAMP OR SOCKET | TOUCH CONTROL PANEL | KEY UNIT | RELAY (RY-1) | RELAY (RY-2) | RELAY (RY-3) | RELAY (RY-4) | RELAY (RY-5) | RELAY (RY-6) | OPENED WIRE HARNESS | SHORTED WIRE HARNESS | POWER SUPPLY CORD | NO POWER AT WALL OUTLETT | MONITOR RESISTOR | FOIL PATERN ON PWB. | OPEN WIRING TO THERMISTOR | AH SENSOR ASSEMBLY | NOISE FILTER |
| MAGNETRON | POWER TRANSFORMER | H.V. RECTIFIER ASSEMBLY | HIGH VOLTAGE CAPACITOR | 1ST. LATCH SWITCH | 2ND. LATCH SWITCH | STOP SWITCH | MONITOR SWITCH | FUSE M8A | THERMAL CUT-OUT 145°C (MG.) | THERMAL CUT-OUT 95°C (FAN) | THERMAL CUT-OUT 150°C (CONV.) | FAN MOTOR | TURNTABLE MOTOR | CONVECTION MOTOR | CONVECTION HEATER | THERMISTOR | DAMPER MOTOR | DAMPER SWITCH | OVEN LAMP OR SOCKET | TOUCH CONTROL PANEL | KEY UNIT | RELAY (RY-1) | RELAY (RY-2) | RELAY (RY-3) | RELAY (RY-4) | RELAY (RY-5) | RELAY (RY-6) | OPENED WIRE HARNESS | SHORTED WIRE HARNESS | POWER SUPPLY CORD | NO POWER AT WALL OUTLETT | MONITOR RESISTOR | FOIL PATERN ON PWB. | OPEN WIRING TO THERMISTOR | AH SENSOR ASSEMBLY | NOISE FILTER | ||
| OFF CONDITION | Home fuse blows when power supply cord is plugged into wall outlet. | |||||||||||||||||||||||||||||||||||||
| Fuse M8A blows when the door is opened. | O | O | O | |||||||||||||||||||||||||||||||||||
| FUSE M8A blows when power supply cord is plugged into wall outlet. | O | |||||||||||||||||||||||||||||||||||||
| "88:88" does not appear in display when power supply cord is first plugged into wall outlet. | O | O | O | O | ||||||||||||||||||||||||||||||||||
| Display does not operate properly when STOP/CLEAR pad is touched. (The time of day should be appear on the display with beep sound during normal condition.) | O | |||||||||||||||||||||||||||||||||||||
| COOKING CONDITION (COMMON) | Oven lamp does not light at door opened. | O | ||||||||||||||||||||||||||||||||||||
| Oven lamp does not light at all. | O | |||||||||||||||||||||||||||||||||||||
| Turntable motor does not operate. (Oven lamp light.) | O | |||||||||||||||||||||||||||||||||||||
| Cooling fan motor does not operate. | O | |||||||||||||||||||||||||||||||||||||
| The oven stops after 1 minute. | O | |||||||||||||||||||||||||||||||||||||
| Oven does not go into cook cycle, when START pad is touched. | O | |||||||||||||||||||||||||||||||||||||
| COOKING CONDITION (MICROWAVE) | Low or no power is produced during microwave cooking (The food is heated incompletely or not heated at all) | O | O | O | O | O | ||||||||||||||||||||||||||||||||
| Extremely uneven heating is produced in oven load (food). | O | |||||||||||||||||||||||||||||||||||||
| Function of variable cooking does not operate properly except HIGH power. | O | |||||||||||||||||||||||||||||||||||||
| COOKING CONDITION (CONVECTION) | CONV indicator lights, but heating element does not heat. | O | O | |||||||||||||||||||||||||||||||||||
| Temperature in the oven cavity is lower or higher than preset. | O | O | ||||||||||||||||||||||||||||||||||||
| When preheating, the oven does not stop. | O | |||||||||||||||||||||||||||||||||||||
| Convection cycle runs 4 minutes and 15 seconds then the oven shuts down. | O | |||||||||||||||||||||||||||||||||||||
| SENSOR COOKING CONDITION | AH sensor does not end during Sensor Cooking condition. (Oven does not shut off when a cup of water is boiling by Sensor Cooking.) | O | ||||||||||||||||||||||||||||||||||||
| Oven stops at 16 sec. after starting | O |