Whirlpool 1997 "E THE CONVECTION HEATING ELEMENT

3-8

THE CONVECTION HEATING ELEMENT

and the heater relay on the microcomputer

board. During a convection, or combination

cooking cycle, the heater cycles on and off to

maintain the programmed cavity temperature.

The heating element surrounds the convec-

tion fan blade and is not visible through the

oven cavity.

The 1400-watt convection heating element is

located under the circulation pulley cover and

the top plate. The heating element heats the

air that is distributed into the oven cavity by

the convection fan. It operates on 120 VAC

and is controlled by the convection thermistor,

TESTING

1. Set the ohmmeter to the

R x 1

scale.

2. Measure across the heating ele-

ment terminals.

You should measure between

40 Ω and 90 Ω @ 68˚F.

CONVECTION

THERMISTOR

BRACKETS

CIRCULATION

PULLEY COVER

TOP PLATE

CONVECTION

HEATING

ELEMENT

YELLOW

WIRES

UNCLIP

ELEMENT

HERE

HEATING ELEMENT

MOUNTING SCREWS

VIEWED FROM UNDER

TOP PLATE

SENSOR

COVER

Contents

Main Page TABLE OF CONTENTS iii Page iv IMPORTANT SAFETY INFORMATION Fire Hazard Electrical Shock Hazard WARNING NOTE CAUTION WARNING CAUTION WARNING TO SERVICE TECHNICIANS OR CAUTION WARNING R.F. LEAKAGE TEST CAUTION EQUIPMENT TEST THEORY OF OPERATION 1-2 N L1 3 1 11 N L1 3 1 13 COMPONENT SECTIONS COMPONENT ACCESS GENERAL REMOVING THE MICROWAVE OVEN & CABINET WARNING 2-3 Removing The Cabinet THE PROTECTION CONTROL SYSTEM REMOVING THE OVEN DOOR REMOVING THE OVEN DOOR COMPONENTS REMOVING THE CONTROL PANEL TURN PANEL OVER REMOVING THE LINE FUSE REMOVING/ADJUSTING THE INTERLOCK SWITCHES REMOVING A SWITCH MAKING ADJUSTMENTS 2-9 1997 Whirlpool Corporation INSET 1 Original March, 1997 4322167 Page 2-9 INSET 2 SECONDARY INTERLOCK REMOVING THE BASE THERMAL FUSE REMOVING THE MAGNETRON THERMAL FUSE REMOVING THE CONVECTION THERMISTOR 2-13 Page 2-13 REMOVE FIVE AIR DUCT SCREWS CONVECTION THERMISTOR WHITE WIRES REMOVING THE CAVITY THERMAL FUSE THE OPERATING CONTROL SYSTEM REMOVING THE OVEN LIGHT SOCKET REMOVING THE CONTROL CIRCUIT BOARD & THE TURNTABLE INDICATOR CIRCUIT BOARD TURN PANEL OVER INSET CONTROL BOARD REMOVING THE FAN MOTOR REMOVING THE POWER CORD POWER CORD REMOVING THE BLOWER MOTOR CAPACITOR REMOVING THE CONVECTION HEATING ELEMENT 2-21 Page 2-21 REMOVE FIVE AIR DUCT SCREWS VIEWED FROM UNDER TOP PLATE REMOVING THE GAS SENSOR REMOVING THE STIRRER MOTOR REMOVING THE TURNTABLE MOTOR REMOVING THE COOKTOP LIGHT SOCKETS THE HIGH VOLTAGE COMPONENTS ACCESSING THE COMPONENTS REMOVING THE MAGNETRON REMOVING THE HIGH VOLTAGE RECTIFIER AND THE HIGH VOLTAGE CAPACITOR REMOVING THE HIGH VOLTAGE TRANSFORMER Page CAUTION 3-1 Warning To Service Technicians! COMPONENT DESCRIPTION & TESTING IMPORTANT SAFETY INSTRUCTIONS Precautions to Avoid Possible Exposure to Excessive Microwave Energy 3-3 CAUTION WARNING THE THERMAL FUSES THE BLOWER MOTOR CAPACITOR R x 10K THE GAS SENSOR TESTING 1. Set the ohmmeter to the R x 1 THE CONVECTION THERMISTOR R x 10K THE CONVECTION HEATING ELEMENT TESTING 1. Set the ohmmeter to the R x 1 MOTORS Blower Motor Fan Motor Stirrer and Turntable Motors PROGRAMMING CHECKS f 2 f 1 CHARTS Page Page CHECKING THE MICROWAVE POWER OUTPUT CAUTION CHECKING FOR MICROWAVE ENERGY LEAKAGE EQUIPMENT MAKING THE MEASUREMENTS Measuring The Oven With The Cabinet Installed . Measuring The Oven With The Cabinet Removed MEASURING MICROWAVE POWER OUTPUT USING THE IEC-705 RATING STANDARD 3-18 TEST CHARTS R x 1000 COMPONENT TESTING WARNING ELECTRICAL SHOCK HAZARD 3-19 3-20 C. N.C. CONTACTS N.O. CONTACTS 3-21 KEYBOARD MATRIX 3-22 CONTROL CIRCUIT BOARD CHECK LIST 3-24 CONTINUITY TEST CHART DOOR OPEN DOOR CLOSED PRIMARY, MONITOR, & SECONDARY SWITCH CHECKOUT PROCEDURE (+) = CONTINUITY () = NO CONTINUITY 4-1 Page 4-1 11 TECH TIPS 1 CN1 CN5 321 321 1 2 3 1 2 3 Model MH9115XE CONTROL MODULE BK = Black BR = Brown RD = Red YL = Yellow GN = Green BL = Blue PK = Pink WH = White NOTES: 1. Oven is Off. 2. Door is Open. TEMP PROBE STRIP CIRCUITS N 2. DOOR IS OPEN OVEN LIGHT IS ON L1 1. UNIT IS PLUGGED IN CLOCK IS WORKING 4. BLOWER MOTOR IS ON HIGH 5. OVEN IS OFF CAVITY TEMPERATURE IS ABOVE 133F BLOWER MOTOR IS ON LOW 6. COOKTOP LIGHTS ARE ON HIGH OR LOW N L1 3 1 11 7. MICROWAVE COOKING IS ON 8. CONVECTION COOKING IS ON N L1 SPECIFICATIONS 4-7 Page 4-7 SPECIFICATION CHARTS 4-8 4-9 Page 4-9 4-10 4-11 Page 4-11 4-12 4-13 Page 4-13 4-14 4-15 MODEL & SERIAL NUMBER EXPLANATION SERIAL PLATE LOCATION 4-16 WHIRLPOOL MICROWAVE HOOD WARRANTY LENGTH OF WARRANTY WHIRLPOOL WILL PAY FOR: WHIRLPOOL WILL NOT PAY FOR: