Timer charts may be for old-skool appliances with mechanical timers, but there are still plenty of old-skool appliances knocking around, so reading timer charts remains a vital troubleshooting skill.
That's exactly what we cover in this workshop: how to cohere the timer chart and the schematic, reading them in tandem. Kind of like they're dance partners in the Timer Chart Cha-Cha!
Topics covered in this workshop include:
How to decipher the rows and columns on a timer chart
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
Got a short and sweet one for you today. Here's the scenario:
You're troubleshooting an LG wall oven that doesn't heat. You've gone ahead and torn it down as much as you could to do an ohms measurement on the broil element (in spec) and the temperature sensor (also in spec). You confirmed that the unit was getting a good 240 VAC power supply. You wanted to test the bake element too, but you didn't have a second man with you, so you gave up on that idea. Instead, you just replaced the main c
The current usage of “Black Friday” came from retailers celebrating the time of year they finally turned a profit.
Master Samurai Tech and Appliantology help service techs and companies to be profitable year ’round!
We’re celebrating Thanksgiving and repair excellence with a Black Friday discount.
Get 10% off everything. It’s never been a better time to enroll in a new course or renew your membership.
What do we mean by everything? Well, everything, which means:
Appli
When it comes to switches in appliances, it's hard to think of one more ubiquitous than the relay. It can be used with and without a control board, and it allows a small voltage to control a much larger voltage. But what exactly does that mean, and how do they do that? And what about triacs, the relay's solid-state cousin?
We cover both of these devices, including how they work and how to troubleshoot them, in detail in this excerpt from one of our recent Live Dojo workshops. Give it a watc
Ghost voltage has misled many a green tech during his troubleshooting. How are you supposed to interpret it when the VAC function of your meter tells you that you have 108 volts going to a load? Is your voltage supply bad? Or are you perhaps simply missing your Neutral?
That's where a loading meter comes to the rescue. By actually putting a load on a circuit, the loading meter shows if there really is the difference in voltage between those two points required for current to flow.
No N
Schematics and wiring diagrams -- two different kinds of service documents that seem similar, but actually serve completely different purposes. One of them is essential to any electrical troubleshooting and should be consulted on every service call, while the other has much more niche applications. But which is which, and how do you tell them apart?
That's what we explore in this workshop, which is an excerpt of the discussion from one of our latest Live Dojo workshops. In it, we go through
What are strip circuits and how do you read them? What purpose do they serve in troubleshooting? Are they better than normal schematics, worse, or just different?
That's what we explore in this workshop, which is an excerpt of the discussion from one of our latest Live Dojo workshops. Parallel to that, it also acts as something of a part 2 to our previous workshop on DC terminology. These schematics that we show have a number of esoteric and straight up confusing DC terminology, but don't w
Refrigeration is its own little world within appliance repair. The presence of a sealed system introduces all kinds of specific knowledge and skills you need to have to properly troubleshoot these machines, from thermodynamics to compressor technology to brazing. And that's not even mentioning the other systems, like airflow and control.
So how do you learn all this stuff? Well, if you want to troubleshoot refrigerators like a real tech, you'll need both brains-on and hands-on trainin
DC power in appliances works the same way no matter the manufacturer, but everyone has their own way they like to talk about it. And if you're not up on the lingo, you'll be left mystified by DC circuits in schematics.
You don't have to worry, though, because we explain all kinds of DC terminology in this latest workshop. From VDC to VCC, we cover everything you're likely to encounter in your troubleshooting travels through DC power, including:
Terms for DC voltage supplies
T
We had some fun in this Live Dojo Workshop! We went beyond the screen into the big, scary Real World and showed off live a few things about BLDC fan motors, including:
BLDC fan motor wire color conventions
Expected readings on PWM and RPM feedback lines
Simulating a PWM signal
Identifying failed speed sensor
...and more! Click below to watch the workshop recording -- viewable only by premium tech members.
If you're an Appliantology tech member and y
Linear motors -- primarily in the form of linear compressors -- aren't new technology, but they've only been migrating into the appliance world over the past few years. These "new" compressors have their own unique failure modes and troubleshooting dos and don'ts. To really have a good idea of how to diagnose them, you need to understand how they work.
That's exactly what we show in this short excerpt from one of our longer technical training webinars. Give it a watch and learn something!
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
How are we as techs supposed to understand the specifications we see on a split-phase motor's label? What's the difference between a motor's output power and its input power, and which of those specs is given on the label? What do acronyms like FLA and LRA mean? All that and more covered in this short video on motor specifications.
This is just a short excerpt from the great technical discussions we have every other Saturday during our Live Dojo Workshops. If you're not joining us for these
We're going to take a dive into what exactly is going on electrically with the high-voltage circuit in a microwave. We'll use this specific schematic as an example, but these principles apply generally.
Don't worry about most of the schematic. All that matters to us right now is the high-voltage section -- the transformer on the right side of the schematic and everything to its right.
If you're not familiar with how magnetrons work (or even what they are), then this circuit
Some techs long for the "good old days" of mechanical controls, when troubleshooting appliances was supposedly simpler. But the universal use of electronic controls nowadays actually provides many troubleshooting benefits -- in particular in the form of error codes and diagnostic modes.
The purpose of error codes is for the control to tell you its best guess of what's wrong, based on the algorithms programmed into it by the engineers. Note that the engineers' best guess is sometimes a very
Why are microwaves so picky about the way they do their door switches? Are two different interlock switches really necessary? And what does the monitor switch even do, anyway? All these questions and more answered in this short instructional presentation.
Big props to Brother @Vance R for his explanation of these switches in this topic, which inspired us to make this video.
Topics covered include:
Schematic analysis of interlock switch circuits
Identifying if the schemat
In this video, we give a comprehensive answer to this question: "Why is it that high ambient temps cause high side and low side pressures to rise?"
This simple question about one specific sealed system problem scenario is a great opportunity to take a deeper dive into how sealed systems work, how they're affected by their environment, and how an issue in one area of a sealed system has ramifications for every other area.
Topics covered include:
The temperature/pressure relation
What do you do when even the service manual can't be trusted?
In this video, we discuss how to deal with bad or missing information in all kinds of tech docs -- service manuals, tech sheets, schematics, you name it. Topics covered include:
Pin numbering discrepancies
Reconciling pinouts with schematics
Identifying power supplies
Recognizing incoherent specs
What are dummy directions?
..and more!
You can watch this one right now for free! We've
We've got an interesting one for you today -- take a look at the "IDI Motor" in this schematic:
That's the ice dispenser auger motor in this fridge, and there are a couple interesting things to figure out about it. First, what's the deal with its power supply? If you look at the label on the motor, you'll notice that it says:
So that's a 120 VDC motor. How does that work?
A quick look through the documentation tells us that this motor is designed to run in two differen
By now, most of us are used to variable speed drive motor systems in appliances. The control board sends a PWM signal to an inverter, which tells the inverter how fast to run the BLDC motor.
While this is the type of inverter that's been used in appliances for years now, it's not the only kind of inverter out there. In fact, another type of inverter is starting to crop up in the appliance world, and it may very well become the norm for some applications. It's called a drop-in inverter, and
Appliantology has always been a community built by techs, for techs, and one of the biggest ways the community grows is by simple word of mouth: techs telling other techs about all the awesome learning, discussions, and tomfoolery that goes on here.
To that end, we've got a great opportunity to show our appreciation and give a perk to techs who spread the good word of Appliantology. All site members, including Grasshoppers, can become Appliantology apostles. "Apostle" means "one sent out" u
Let's look at a seemingly simple load that has more going on than you would think: a multi-speed hood fan in a microwave. The questions we want to answer are: how many speeds does this fan have and how does it achieve those speeds?
If you look at the spec block for the motor, the answer to the first question seems easy -- looks like it's a simple two-speed motor.
But when you look elsewhere in the tech sheet, you find this voltage table that seems to state you have four speeds. (
Imagine you're in this situation: you're trying to do some ohms testing on the heater of an LG electric dryer. You're reading 21 ohms across a single coil, and 42 ohms through both coils. But when you look at the spec on the schematic, you're seeing almost exactly half that:
Weird. Maybe the heater is out of spec, but that's a weird discrepancy. And it's bizarre that we're reading double the specs given.
Can we get a second opinion? You look elsewhere in the manual, and you find
If you read my previous post about sealed system basics, you know that understanding the thermodynamic states of refrigerants (saturated, subcooled, and superheated) is essential to sealed system troubleshooting. In that post, I explained these states in terms of a simple pressure-temperature table. While that keeps things simple, it doesn't really give you a strong visual and mental model for how the refrigeration cycle works thermodynamically.
That's why we're going to spend this whole po
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