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      Webinar Recordings Index Page   10/03/2017

      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) 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] Samurai's Sealed System Sleuthing Secrets - 10/30/2017 @7PM ET   10/19/2017

      Having laid some theoretical groundwork in the last webinar, we're going to focus on practical considerations in this one. That means quick n’ dirty techniques for diagnosing sealed system problem using strategically chosen and skillfully interpreted temperature measurements.  Review homework from the first session on 10-2-2017. Home refrigerator practical design and operating rules-of-thumb useful for troubleshooting Practical application exercises Troubleshooting scenario exercise Techniques for making system temperature measurements for determining superheat and subcooling Sealed system diagnosis homework assignment (to be reviewed in the next webinar in this series) If you attended the first webinar in this series, this is your payday! We’re going to apply that keen, penetrating insight you now possess into money- and time-saving shortcuts you can use to diagnose real-world refrigeration systems on service calls. See this calendar event for more details                   
GRS12

Lennox G26Q3-75-1 thumping noise before induction motor starts

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GRS12

Hi All:

I have a Lennox G26Q3-75-1 furnace. Just before the inducton motor starts, there is a loud noise (thumb) that seems to come from inside the walls.

At first I thought it was the house moving (getting cold out, figured the house will groan a bit), however this has been a constant thing right before the furnace kicks on.

I've sat next to the furnace listening for the thump..no luck. When upstairs I can hear the thumb quite clearly. And again, only happens as the furnace is about to cycle.

Any ideas?

Thanks,

Glenn

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applianceman18007260692

Have you checked the return air vent pipe to see if it is loose?

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RegUS_PatOff

thermal expansion of the vents from cool air entering ?

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applianceman18007260692

That is what I am thinking. Is their a rain flap mounted on your inducer vent?

Edited by applianceman18007260692

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GRS12

Gentlemen: Thank you for responding. I've checked all of the pipes/ducts that I can reach, everything seems tight and secure. There is a rain flap, but when the flap moves due to wind or whatever, the sound is quite different.

Thermal expansion/contraction does play a part of this, however, I don't believe all of the thumping is from expansion. Some of the thumps come right before the inducer motor comes on. As I said, I've sat next to the furnace thinking it may be a switch or something, and there is no unseemly noise there when it starts up.

Very odd.

Again, thanks for your replies.

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