I want you to take a look at the door switch I've circled below. Think about it for a minute, then answer one question: what single test could you do to prove beyond a doubt whether or not that door switch is operating within spec?
There's no trickery going on here -- it's just a simple switch. But many techs will test it using a flawed, limited test that has a big chance of leading them to the wrong conclusion. And they'll do a bunch of unnecessary disassembly. Post your answer in th
More and more folks are doing online training webinars these days -- so many, in fact, that it can be impossible to keep up with them all. Recently, Samsung and MSA both put out training webinars on Samsung dishwasher technology and troubleshooting, and I figured I would share the love with the Appliantology Brethren.
In the links below, you'll find my notes and screenshots from both webinars. Topics include:
Troubleshooting the OC/OE error
Identifying common sources of leaks
This microwave will run with the door open -- lucky for the customer, it also doesn't heat. But why is the turntable able to run with the door open? What do you do when a circuit doesn't work at all the way it's supposed to?
That's exactly what we discussed in our latest Live Dojo workshop.
Topics covered include:
Microwave door interlock switches
Turntable motor circuit analysis
Control board algorithms and relays
Theorizing a reasonable failure scenario
Merry Christmas to all the Appliantology Brethren! Here's hoping that this holiday is capping off a great year for your business, and that an even better year is just around the corner.
It's always the old-skool style circuits that have the most interesting electrical issues, isn't it?
In this workshop, we took a look at just one such machine. A missing neutral in the power supply doesn't have the effect that you would necessarily expect. For example, in this dryer, the timer motor runs on 240 VAC, but the drive motor runs on 120 VAC power. With a missing Neutral, the drive motor won't run, but the timer motor will. We go all into that, as well as the kind of troubleshooti
When you see a term like "FlowSense" in a service manual, don't immediately assume that you're dealing with some bizarre, new technology. 99% of the time, it's just a fancy brand name that the manufacturer slapped on a bit of simple tech that's been around for decades.
And that's what you're going to see in this video! in it, we show how "FlowSense" is just a fancy name for a single sensing line on the control board that detects the presence or absence of L2. Watch it now to learn exactly
If a dryer's motor isn't running, and you hear a strange humming noise coming from the start switch, what does that mean for the switch? And if you want to test that switch, what's the best way to do that?
These are questions that we answer right here in this short excerpt from one of our many in-depth technical training webinar recordings. Give it a watch and learn the answers for yourself...
Want to watch the full webinar recording? Click below -- viewable only by premium m
We had an interesting discussion at our most recent Live Dojo workshop! This dryer only runs when the push-to-start button is held down -- a relatively simple problem, but troubleshooting it requires us to understand the entire motor circuit and how it works on startup.
We began by using Ten-Step Tango to orient our troubleshooting, identifying our Load of Interest and analyzing its circuit.
This led us to examining how the start switch works, which includes some interesting components
In this interactive webinar workshop, we explored an LG gas dryer issue that had stumped an Appliantology tech. We performed a forensic analysis on the troubleshoot to figure out how it could have been improved, and then we moved on to thoroughly examine the circuits and understand how they work.
This and our dozens of other technical training webinar recordings are only viewable by premium tech members at Appliantology.
Topics covered include...
DC and AC loads
Compute
This past Sunday, we gave a webinar covering everything you need to know about thermal controls in dryers and the underlying technologies behind them. The full recording dives into all the details of identifying, understanding, and troubleshooting these ubiquitous devices.
In this short clip, we'll introduce you to the three technologies and show how different manufacturers give them various (and sometimes confusing) names.
Want to watch the full webinar recording? Click belo
In our latest troubleshooting workshop, we start with a seemingly simple problem -- overly long dry times -- and walk through all the surprising pitfalls that you could be ensnared by. Topics include:
Correctly measuring dryer vent airflow
Differentiating between real diagnostic tests and fluffy sales features
Identifying dummy troubleshooting directions and errors in manuals
Learning why you should always use amps rather than ohms for troubleshooting AC loads
Specs are essential for troubleshooting. After all, to test a hypothesis, you need to make electrical tests, and to make electrical tests, you need to know what your expected readings are. However, manufacturers don't always give you everything written out. What do you do if you need to make an amp measurement, but the manufacturer only gives you watts? That's exactly the question we're going to answer in this excerpt from one of our many in-depth technical webinar recordings.
Wan
See if you can identify two things on this Samsung dishwasher schematic:
1. Where does the control board receive line and neutral?
2. Where do the sub-control boards get their DC power supply?
The answer to the first question can be found easily enough, if you have a little schematic reading experience. But it's a bit trickier for those who don't have as much practice.
For one thing, line and neutral aren't explicitly labeled. Just wire colors are given, but fortunately
There are a lot of funky things going on on this Electrolux dishwasher schematic -- including normal-looking switches that are labelled "transistor switches". What does this label mean, exactly, and how does it affect our troubleshooting? That's what the Samurai breaks down in this short clip from a longer technical webinar recording.
Want to watch the full webinar? Click below to watch -- available only to premium members.
Be warned: this week's troubleshooting scenario is somewhat chilling...
...or maybe not, since the problem is that the ice dispenser isn't working. In fact, the entire fridge shuts down when the ice dispenser is activated. How can this be? Well, in this recording from one of our biweekly Live Dojo workshops, we go over the relatively simple cause to this strange issue.
Loading down is the culprit here. That's when a faulty load grounds out the control board's DC power supply, causing a
Long gone are the days when we techs had any excuse to be scared by names like LG or Samsung. Through information tools like Appliantology, we have access to all the technical docs we need to service these models. And anyone who has spent time examining the schematics and service manuals for Samsung appliances knows that there's nothing weird or proprietary going on here -- maybe a bit of Korenglish here and there, but how electricity works and the fundamental technology used in all appliances i
When a control board doesn't seem to behave the way it's supposed to, does that mean it's always time to replace the board? How do you avoid the dreaded callbacks on service calls where you replaced the board because you had no idea what else to replace? Is there a way to reliably troubleshoot computer-controlled appliances and avoid guesswork when it comes to the control board?
Of course there is, and Team Samurai is going to show you how!
It all boils down to understanding how these
More than any other AC load, motors are all about amps.
What do I mean by that? When you have a motor that is misbehaving, the best, most informative electrical test you can do by far is amps. And one of the worst mistakes you could make is to just rely on ohms when testing a motor.
In this recording from one of our biweekly Live Dojo workshops, we go over several different aspects of troubleshooting motors.
Thermal controls are the first order of business. All AC motors have an i
Ever looked at a timing chart and been mystified by how to decipher it? Or maybe you're looking at the schematic, and you can't make heads or tails of which switch is supposed to be closed when during a cycle.
If timer charts have ever given you trouble, then this is the video for you. In less than 10 minutes, we'll show you how to read a timer chart, correlating it with the actual steps of the cycle, and then identifying how it relates to the state of the switches on the schematic. Give it
Here's the situation: the tech has a Maytag dishwasher with no lights, no life, no nothin'.
With a multimeter on LoZ, the tech has already checked the following with reference to ground. Here are his findings that he reported:
Seeing that there was a solid 120 volts to the board and no operation, the tech concluded (with the aid of a few ohm checks across the control board) that the board was the culprit. He replaced it, and...
Still nada.
How could such a seeming slam-dunk
While all appliances use the same fundamental technology, their manufacturers often talk about them using different terms. Let's talk about DC power supplies and how not to get tripped up by the different terminology used there.
First off, the very basics. Just like in AC, any DC circuit needs two legs: the voltage supply, and the return. The return is called Ground in DC. Don't let that confuse you -- DC ground is NOT AC ground-- they are electrically distinct and separate. Ground is to DC
The general rule for dryer vent airflow is that, if the airflow feels like a breath (even a strong one), then you have a problem. This rule of thumb will serve you well a lot of the time, but sometimes a "calibrated palm" just isn't enough. Sometimes, you need to get an actual measurement of the airflow so that you can compare it to the specifications.
What you really want to know is the volumetric flow rate of the dryer exhaust. That is, how much air it's pushing out over a particular peri
Loading down is a failure scenario unique to DC power supplies, and if you don't know what to look for, it can leave you scratching your head and eating some expensive parts. How do you identify that you have a potential loading down scenario, and what steps can you take to verify that? That's exactly what we cover in this Master Samurai Tech Workshop.
Topics covered include:
How DC power supplies work
How they affect the board's operation
What loading down is and how
There's a very common configuration of valves that are used in refrigerators with ice makers and dispensers -- so common that every tech should be very familiar with how it works and what terms are used to refer to it. You can't troubleshoot what you don't understand!
We'll use a GE refrigerator as our example, but this same system is used across almost all refrigerators with water supplies. Here's a snippet from a GE manual:
All this is saying is that you have three valves in th
Refrigeration can seem a bit like magic -- how does a little bit of refrigerant being pushed around in some metal tubes somehow chill a freezer down to 0 degrees F? Well, it's not magic -- it's just physics. But granted, it's an aspect of physics that we don't often interact with in our daily lives, and it can be a bit unintuitive at first.
It all has to do with how a material can absorb heat without actually getting hotter. How does this happen? That's what we explain in this excerpt from
