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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

      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.   

Samurai Appliance Repair Man's Blog

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Soot: A Clear and Present Danger in your Gas Oven

Samurai Appliance Repair Man

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I was at a service call on gas range the other day for an oven that wouldn't bake or broil. The cause turned out to be a bad range control board. Nothing unusual about that. The astonishing thing with this range was the inside of the oven cell-- all the surfaces inside were coated with a thick layer of soot (click the images for a larger view):

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This is NOT a normal condition in any gas range. If you see soot accumulated on your oven cell walls, even a little, STOP USING IT AND GET IT CHECKED OUT!

Soot is a product of incomplete combustion. So is Carbon Monoxide (CO), dubbed "the silent killer" because it is odorless and kills by displacing oxygen in your blood, making you sleepy and, in high enough concentrations, can make you take that final dirt nap. We've all heard the stories of people dying in their homes from CO poisoning. Improperly adjusted gas appliances, like the oven shown in the photos above, is one of the more common ways this happens.

A standard practice in the appliance industry is that all gas appliances, ranges, ovens, dryers, etc., come ready to burn natural gas. If you're going to use propane (also abbreviated LP for "liquid propane"), you have to convert the gas system in the appliance to safely burn it without producing soot or unsafe levels of CO.

Since propane burns hotter than natural gas (2,500 Btu/cu ft for propane vs. 1,030 Btu/cu ft for natural gas), it needs more air to make a "complete" (or at least safe and soot-free) combustion. If the air-fuel ratio (AFR) is too low (too much fuel or "too rich" in automobile terms), you'll create soot and unsafe levels of CO. If you're interested in some numbers on the AFR for natural gas and propane, start here.

While no combustion is 100% complete, you can still get close enough to prevent soot formation and keep CO production to safe levels.

The range in this service call is a Kenmore (Frigidaire-built) range that was purchased from a famous, nationwide retail chain (I'll give you one guess; hint: it's a Kenmore). This range, like all gas appliances, came ready to burn natural gas and needed to be converted for use with propane.

The customer paid the retailer for the conversion but it wasn't done properly. They converted the gas burners on the cooktop correctly by replacing the gas metering spuds for each burner with the smaller diameter spuds sized for propane. But they completely neglected to convert either of the gas burners in the oven (bake and broil). Behold (click the images for a larger view):

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To make matters even worse, when the customer called the retailer's customer service department to complain about the soot in the oven, they advised her to run the self clean feature which successfully produced copious amounts of soot and, at the 900F temperatures reached in the oven cell during self clean, baked the soot onto the oven walls. The soot will never come out. This range is only three years old and the oven is effectively ruined.

So how is the strange and mysterious conversion process done in gas ranges? It's really not a mystical experience at all. It's as simple as following the instructions and installing a few pieces that all manufacturers provide for this very purpose. For example, here is an official conversion instruction sheet that Frigidaire includes with the conversion kits for its ranges. GE's conversion instruction sheet has similar information but I think it's a little more comprehensive and easy-to-follow (you'll need to be an Appliantology Apprentice to download it).

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