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      Webinar Recordings Index Page   11/07/2017

      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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      [Webinar] Appliantology Workshop   11/09/2017

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cuzzin sam

a general defrost question

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cuzzin sam

I unfortunately don't have the model # for this GE side by side but I'm hoping someone can shed a little light anyway.

I first went to this call and found the evap frozen and the defrost heater burned out. I replaced the hearer, defrosted and left only to be called back a few days to find the evap frozen again. The heater and the termination thermostat both read closed so as an experiment I jumped around the thermostat, defrosted and left.

A couple of days later it was frozen again so thru a process of elimination I decided it had to be the board...which I changed...and of course it's frozen again. This parts changing idjiit is getting tired.

Does the board send the unit into defrost based on time or is there a thermister or something that tells the board when to initiate a defrost cycle? If I jump the terminals on the board (I read that here last night) am I simply supplying voltage to the defrost circuit or am I closing the defrost relay on the board? And the big question, has anyone ever seen someone change so many parts with no appearent idea of what he's dong? Thanks for the desperately needed help, Sam

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RegUS_PatOff

... or is there a thermistor or something that tells the board when to initiate a defrost cycle?

yes ,. when to terminate the Defrost
The Control Boards usually have a test for ther Thermistors and the Defrost Cycle
Freezer may have (2) of these
Fridge may have (3)
click on picture
Thermistor-WR55X10025-00855831.jpg

the "older" style were prone for failure
http://fixitnow.com/wp/2010/06/30/ge-profile-and-arctica-refrigerators-upgraded-thermistors/
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Samurai Appliance Repair Man

No, the board decides when to initiate defrost based on door openings, and other factors. The evaporator thermistor tells the board when to terminate the defrost; the board terminates defrost when the thermistor reads 75F. Now, suppose the thermistor's resistance was such that the board always thought it was 75F, what would happen? Answer: the board would never initiate defrost because it thought the evaporator was already too warm.

Check the thermistor resistance by placing it in a glass of ice maker. Should get about 16 K-ohms. If it's one of the old style, it needs to be replaced in any event.

Thermistor part link ==> http://www.repairclinic.com/PartDetail/Thermistor/WR55X10025/914093

Thermistor-WR55X10025-00855831.jpg

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