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      On-demand appliance repair training videos for Professional Appliantologist members Over 30 hours (and growing!) of original, high quality appliance training webinars developed and given by yours truly are at your fingertips, on topics you won't find anywhere else. Fill in those knowledge gaps, strengthen those areas of uncertainty, and boost your skills. Watch on mobile or desktop at your convenience whenever, wherever.  Ultra Short Primer on Basic Electricity, Circuits, Ohm's Law, and Schematic Reading (Length: 1:04:48) Basic Refrigerator Troubleshooting (Length: 1:10:45) Schematic Reading Workshop, 10/2015 (Length 1:19:08) Troubleshooting Strategies for Computer-Controlled Appliances (Length: 48:34) Semiconductors and PN Junctions (Length: 1:04:37) Appliance Temperature Sensing Devices & Technology (Length: 1:27:33) Voltage Measurements, Meters, Ghost Voltages, and Triac-controlled Neutrals (Length: 1:29:32) Troubleshooting with Tech Sheets, Part 1, 4/2016 (Length: 1:09:26) Troubleshooting with Tech Sheets, Part 2, 4/2016 (Length: 1:21:11) Tech Sheet Review, 4/9/2016: Bosch Speed Cooker, Amana Refrigerator, GE Glass Cooktop Range (Length: 1:22:58) Pulse Width Modulated (PWM) Switches used in Samsung Switched Mode Power Supplies (SMPS) (Length: 27:07) PWM Computer Cooling Fan in a Whirlpool Refrigerator (Length: 14:53) Understanding AC Split-phase Household Power Supplies (Length: 52:41) Troubleshooting a Samsung Electric Dryer without Disassembly using Live Tests and the Schematic (Length: 22:47) Troubleshooting a Bosch Dishwasher No-Heat Problem using the Schematic and Live Tests (Length: 15:38) Linear Motors and Linear Compressors (Length: 55:54) Bi-directional PSC Drive Motor Systems in Whirlpool VM Washers (Length: 56:52) Appliance Service Call Structure and Troubleshooting Strategies (Length: 1:00:16) The Ten Step Troubleshooting Tango and Workshop Exercises (Length: 1:35:39) Troubleshooting Ten-Step Tango Advanced Workshop (Length: 1:32:06) Ten-Step Tango Troubleshooting Workshop: Refrigerators (Length: 1:35:57) Whirlpool Duet Washer Schematic Analysis & Whirlpool Dryer Moisture Sensor System (Length: 1:03:04) Neutral Vs. Ground, Inverter Microwave, Digital Communications, Loading Down in DC loads, and more! (Length: 1:14:45) Gas Oven Service Call After a Parts Changing Monkey (Length: 36:04) AFCI and GFCI Circuit Protection Technology (Length: 41:26) Troubleshooting Samsung Refrigerators and more (Length: 1:29:58) 3-way Valves and Dual Evaporator Refrigerators (Length: 1:15:45) Split-Phase Compressors and PTC Start Devices (Length: 1:11:57) Gas Dryer Ignition Systems (Length: 53:50) Refrigerator Sealed System Thermodynamics, Part 1 (Length: 43:07) Refrigerator Sealed System Thermodynamics, Part 2 (Length: 1:09:09) Refrigerator Sealed System Thermodynamics, Part 3 (Length: 1:11:56) Refrigerator Sealed System Thermodynamics, Part 4 (Length: 37:45) Refrigerator Sealed System Thermodynamics, Part 5 (Length: 16:35) To access these webinars and all the other info-goodies here at Appliantology, become a Professional Appliantologist today. If you need cost-effective, time-flexible, state-of-the-art appliance technical training, check out the Master Samurai Tech Academy.
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Troubleshooting tip for Whirlpool inverter-type microwave ovens with an F7 error code

Samurai Appliance Repair Man

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The high voltage system in microwave ovens is used to power the magnetron and generate the microwave sound energy that cooks the food. This voltage is in the range of 2,000 vdc. There are two ways of producing this high voltage. The older, conventional way is using a high voltage transformer, capacitor and rectifier. This is a pretty reliable configuration and easy to troubleshoot and repair.

The other way of producing the high voltage for the magnetron is using an inverter board. These are ofter nightmares to troubleshoot and expensive to repair.

In these Whirlpool inverter-type microwaves (built by Panasonic), the F7 error code indicates a problem with the inverter board.

Sometimes you may see a burned spot on the inverter board confirming the error code. But absent any visual confirmation like that, Brothers JJ Surfer and Chat_in_FL offer this heads-up when troubleshooting Whirlpool inverter-type microwave ovens that throw an F7 error code.

Be careful.. I've had a bad mag throw the same error, I would check mag for shorts and continuity first before ordering inverter board, high limit t-stat on cavity or mag could cause dead condition (no display) although I don't think those reset.

As JJ Surfer just said: Also check magnetron terminals to ground. After replacing the inverter and control board, I've found a shorted mag will also give you this F-7 error code, indicated by pulsing power to the mag just before the error code is displayed...

Test the magnetron by ohming between the terminals, should be very low resistance, typically less than an ohm. Then check from one of the terminals to the magentron casing. Should wide open-- if you read continuity or some resistance, then the magnetron is bad.

If the magnetron checks good, you can get the replacement inverter board here:

1100 watt Inverter board: http://www.repaircli...mber=GH6177XPS5

Inverter-Board-W10217710-00688011.jpg

40 watt Inverter board: http://www.repaircli...mber=GH6177XPS5

Inverter-Board-8204989-01459787.jpg

Source: Whirlpool Microwave