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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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      [Webinar] Appliantology Workshop   11/09/2017

      Information is the name of the game in the appliance repair trade today. Appliantology is a powerful information tool for the professional appliance repair technician. But just like with any of the more capable tools in your tool bag, many of the more powerful features are hidden from you unless you "read the manual." Ugh! Who wants to do that? Well, this is one time when you don't have to! In this webinar, Team Samurai will personally walk you through the site and show you many of the useful and powerful features that even long-time users probably never knew existed.   

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Theory of Operation of Electrode Gas Flame Detection

Samurai Appliance Repair Man

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If you're working on a gas stove where the burners keep clicking even after the flame is established, you may be tempted to throw a new spark module at it and hope for the best. But you would probably be disappointed. Let's start the troubleshooting process with a fundamental understanding of how the spark module is supposed to detect that the burner has established a flame:

Come with me now on a wild romp through the theory of operation of electrode gas flame detection...

If you look closely at a finger of burner flame you will see that it is clearly made up of three separate elements: 1. Inner fuel rich cone 2. Ionized blue outer cone with current carrying capabilities and 3. Outer air rich mantle. When gas combined with air; burned energy is released in the form of heat and light. When the gas / air mixture is controlled, the outer blue cone will actually carry electrical current similar to a wire.

If we place a metal probe into this “Ionized Plume” and apply a voltage between it and the burner, current will flow. An important characteristic of a burner/flame/electrode assembly is its ability to mainly pass current in one direction. It behaves as a one way valve or rectifier.

Flame Rectification systems make use of this directional characteristic when detecting a good flame to distinguish it from leakage currents that can arise due to moisture contamination, soiled igniter tip, poorly grounded burner spreader ring / burner head, cracked igniter insulation or poor house ground.

An AC voltage is applied to the electrode from the spark module and the resultant current flow which is greater in one direction than the other, is electronically detected. This current is very small, about one microamp (one millionth of an amp).

The minimum recommended flame current measured under all likely conditions in an installation should be 1.0 microamps for re-igniters. When a burner flame is present the Ionized outer cone will be producing a small DC current. This current is known as Flame Current. The flame current has to be at a certain level to allow voltage from the spark module to flow efficiently.

The accurate placing of the electrode in the flame is important. This igniter tip needs to be perfectly located in the ionized outer blue cone to effectively send and then detect current flow.

To break it down further, the spark module acts as a simple capacitor. It saves voltage like a sponge until it can hold no more. It will save and release this voltage approximately 3 times per second. When the voltage is released it follows the spark wire until reaches the spark electrode tip. The built up voltage wants to leave the tip and move to the point of least resistance. In a healthy situation this will be the burner spreader ring. From the burner spreader ring the voltage flow will pass through the burner head, burner tube, chassis and to ground. An interruption of this current path will cause the spark system to misbehave, such as with the continuous clicking problem.

Source: G.E. ZGU36L6H4SS Cooktop

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