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    • Samurai Appliance Repair Man

      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.
    • Samurai Appliance Repair Man

      [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                   

Samurai Appliance Repair Man's Blog

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Understanding how the Water Level Sensor in LG Washing Machines work

Samurai Appliance Repair Man

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Water level sensing in LG washers is done differently from how you may be used to seeing it done in other brands. Whirlpool, GE, Electrolux and others use an air tube connecting an air dome on the tub to a pressure sensor with a physical diaphragm or transducer that "feels" the water level increase as an increase in pressure inside the air tube. LG uses frequency measurements. How's that again? I'll let Brother john63, Dean of LG Appliantology explain:

The Water Level Frequency Sensor operation is based on the displacement of the *coil* attached to the diaphragm.

When the *coil* raises or lowers---it changes the electronically resonant characteristics of the oscillator circuit.

The water level is measured by the Main Board---by frequency readings.

I've never had a failed Water Level Sensor.

It is best tested while on the washer---by using the TEST MODE.

On most LG washers---the Test Mode is enabled by pressing and holding the SPIN SPEED and SOIL LEVEL buttons---and then pressing the POWER button (release all 3 buttons and wait for the door to lock).

Press the START / PAUSE button 4 times at one second intervals (Prewash Cold Water Fill)

The display read-out on the Control Panel will show the *frequency*

Empty---the frequency read-out should be about 255

A tub full of water should show a frequency of about 214 (depending on model number)

Some of the errors that can be displayed---relating to water fill are...

IE error:

Little or no water---usually caused by a failed Water Valve

FE error:

Too much water (overflow detected)---Can be a failed/stuck open Water Valve or blockage in the black air tube which is connected to the Water Level Frequency Sensor. Disconnect the tube from the sensor---and blow air back into the tub to clear obstruction.

To test the Water Level Frequency Sensor outside of the washer...

Use a test meter to check the ohms between pins 1 and 3 (should have between 21 & 23 ohms).

Source: LG PRESSURE SENSOR OPERATION

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