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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                   
CvW

Dehumidifier failure mode?

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CvW

Hi all,

 

I have a question regarding a couple of dehumidifiers that I installed in my in-laws basement, circa 8/2011. They are fad704dud frigidaire 70 pint/day units hooked up to drains so no bucket emptying is usually needed. All three were running for a long time on initial hookup to dry out the basement, controlled it.

 

This year one unit kept running but produced no condensate, I diagnosed it as sealed system failure and the company was nice enough to offer a refund on the purchase price. 

 

The two remaining units are producing condensate but also ice up almost immediately on startup. I am scratching my head re: this behavior given that it's about 65-70*F in the basement and the humidity is only 65-70%. In other words, these units shouldn't be featuring a evaporator HX that is half clogged (growing from the bottom to halfway vertical on HX) with condensate after just 1/2 hour runtime. 

 

The replacement unit I bought (FAD704DWD) has a noticeably higher discharge temperature and almost no condensate frosting, even after a full day of non-stop running under similar conditions. The two older units ice up so badly that the condensate buckets fill over time from ice forming on the bottom of the drain pan (above the bucket) and dripping down. 

 

So here is my question: Do you think that the remaining two units may be on the verge of suffering from a sealed system failure also? That is, is the system so starved for refrigerant that the evaporator is cooling too effectively, leading to instant ice formation? 

 

I have put the two remaining units on interval timers to limit ice growth but am thinking that may not be sufficient a band-aid. If 1/2 of the HX turns into a ice block within 1/2 hr of operation while in a warm basement with relatively benign humidity levels, something is off... Any insights are appreciated. Thanks! 

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RegUS_PatOff

... The two remaining units are producing condensate but also ice up almost immediately on startup.

pictures ?

is the Fan running OK ?

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CvW

Hi, the fan is running, though the outputs do not seem quite as high as on the -DWD unit. Could be the icing. As far as a picture goes, here is a frontal shot with the water bucket and air filter removed. 

post-85824-0-22022800-1379865660_thumb.j. The evap is about 75% covered in this picture, about 3/4 of an hour after startup.

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CvW

FWIW, the speed of icing seems to be correlated to the ambient humidity. When the humidity is around 60-65%, one of the two -DUDs is not icing at all, the other is still icing quickly. Icing was almost immediate in 80% conditions. The DWD has yet to show any icing despite similar conditions.

 

In the meantime, I have taken a look around the web. It appears that if all other variables can be eliminated (i.e. dirty filter, low fan speed, dirty HX, etc.) that low refrigerant charge can be a fairly cause of evaporator HX icing, especially when it is humid and cool at the same time. 

 

Methinks that the remaining DUDs are probably low on charge (one more than the other) and hence on their last legs. Correct me if I'm wrong, but given that these units do not feature schrader valves, it's likely uneconomical to have them recharged?

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RegUS_PatOff

I'm not a sealed system master, but, yes, looks like a low charge from a leak.

Schroeder valves can be installed, charged, then sometimes they actually remove the Schroeder valve and crimp & solder.

But may depend on where the leak is ... (to be repaired)

but may or may not be worth it on a Dehumidifier

 

 

 

 

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