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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.   
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klawleman

Lennox AC HS24-651-1P

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klawleman

I suggest you try to test to ground at the contactor once again , with the new meter . maybe disconnnect the crankcase heater totally and try to restart the unit.

Maybe only have the compressor in the circuit and try to restart.

Maybe try to replace breaker that trips , just in case of a bad breaker.

Last option . buy a new unit...confused.gif

I am not sure how to test the contqctor to grund, but I isolated it by removing all wires connected to terminals and probed each terminal to the grounding lug. No resistance. Measuring from one coil terminal to the other, I got 9 ohms. If I measure from the load side to the grounding lug I get no resistance. The contacts are burnt but they open and close. Even when the CB pops the contacts remain closed until the thermostat control is turned from cool to off.

I disconnected the crankcase heater. I tried this earlier and the results were the same. No difference.

Earlier I tried swapping the load lines from the 50 A breaker to the next largest one I had on the board, a 40, and it made no differnce. Still, it was possible that a good 50 might handle what a good 40 could not and I got one from the HD. It still popped with a new 50 Amp.

I ascertained by trial and error that it only pops if both the Black wire from L-1 is connected to the common terminal of the compressor and the Red wire from L-2 is connected to the Run compressor terminal. If either is disconnected from their respective contacter load terminals, nothing pops. I take that to mean that the short is in the run winding.

The circuit breaker opens if the yellow lead to the start winding is disconnected, but common and run terminals are still connected. If the yellow is connected but either the common or the run terminal is disconnected the cb still does not open. I may be misinterpreting this, but this suggests to me that the start winding is good but the run winding is shorted.

One thing that I don't understand is why I don't hear a humm from the start winding trying to do something, even if by itself it cannot start a compressor. Perhpas there is a delay before the start winding kicks in and the thing shorts before that can happen. It is immediate.

As for replacing it, I contacted a 4th contractor, actually Home Depot who will have one of its contractors call me.

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klawleman

I should have asked how do I test the contactor. What I have done is to ohm between all contacts to ground and the other contacts, and everything was an open circuit. (The exception being a reading of about 8 ohms across the coil, not from either coil contact to ground.)

As for violtage readings, I haven't attempted to take any with the entire system energized. With everything disconnected, except the load lines to poles 1 and 2, I got readings within a couple of tenths of 120 V at each. (contacts open)

On the load side I got .021 V on L1 and .027 for L2. (contacts were open)As miniscule as a reading of 2/100 or 3/100 volts may be, could that likely be a direct short when a start up load is pulled across those contacts?

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RegUS_PatOff

maybe disconnect only the Compressor and re-try the Circuit Breaker ...

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klawleman

I already figured out that the breaker didn't pop unless both the leads to the common and run terminals of the compressor were connected to the two load sides of the contactor. To rule out any possibility of the contactor being the problem, I just got done using wire nuts to directly connect the same compressor leads directly to the lines from the house and the breaker popped. I replaced the breaker, which felt mushy and was no longer difinitely opening, with a new one and it popped wide open. I suppose that rules out a short in the contactor being the problem.

Nothing else was hooked into the circuit; neither capacitor, the contactor, the fan motor, the crnaksaxe heater, or the potential relay. Nothing.

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ACtechGUY

Kudos for trying everything in an effort NOT to buy a new A/C.thumbsup.gif It was clear a while back that you were doomed. whistling.gifWe all have to learn the hard way...............wallbash.gif

By the way if you abuse a circuit breaker enough... ...AND YOU DID !!! . It WILL fail..

It is clear that you either live somewhere where it is not REALLY hot or you done got yerself 'A BIG 'OL HOUSE' and this system serves an area that you maybe don't use much.

If neither of the above are true then I suggest investing in the highest SEER A/C you can buy . Electricity is not getting any cheaper from now on.

Good Luck, Because all brands suck or break in one way or another.

Edited by ACtechGUY
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klawleman

You got it. It is a pretty big house but it gets pretty hot here. Fortunately it is low humidity. What saved us is the 4 ceiling fans I installed a couple of years back. Thanks for the help. At least I know I didn't pass an opportunity to ressurect the old thing from the dead. You may have a point about buying a higher SEER rating. Electrical is just going to get more expensive the same as gasoline. Anyway, thanks again.

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