Ever wondered what the inside of a gas dryer valve looks like? And what's the purpose of having two separate valves in one component? What about those mysterious "safety" and "booster" coils?
All of these questions are answered in this short excerpt from one of our many in-depth technical training webinar recordings. Give it a watch and, if you want to see more, click here to watch the full recording. This and dozens hours more of technical education are available only to our premium member
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
We techs should always be looking to sharpen our repair skills, and one of the best ways to do that is to learn from each other's experiences.
In this excerpt from a longer webinar, the Samurai walks through a Bosch dishwasher no heat problem that he encountered, working through his thought process and schematic analysis step by step. Watch it and learn a thing or two!
Want to watch the full webinar recording? Click below -- viewable only by premium members.
When it comes to troubleshooting BLDC motors and inverters, there's usually a standard strategy. You check the input to the inverter (a good 120 VAC power supply and a PWM signal from the main control) and you make sure the motor windings are in spec and all the same resistance. But what about measuring the output of the inverter?
This is certainly possible to do, and it can be a useful measurement, especially in hairier inverter troubleshooting scenarios. But before we get into that, let's
How you go about your troubleshooting makes all the difference between whether you're a Parts-Changing Monkey or a real appliance repair technician. While parts-changers rely on pattern recognition and rote memorization of "if this problem, then that part", a real tech uses analytical troubleshooting techniques and understanding of the technology involved to get to the right problem every time.
That's exactly what this excerpt from one of our technical training webinar recordings demonstrat
Ever wondered how L1 and L2 in a 240 VAC circuit have a voltage difference of 240 VAC? Or what people mean when they say that L1 and L2 are 180 degrees out of phase? And what exactly do we mean when we say "voltage difference" anyway?
We cover all these topics in this short 6-minute excerpt from one of our many in-depth technical webinar recordings. If you've ever been mystified by the inner workings of standard, split-phase household power, look no further! Give this a watch and be enlight
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
Both of the big Korean manufacturers -- LG and Samsung -- have a little trick that they like to use in their schematics. While I think they do it to keep the lines from becoming too much of a tangled mess, it can sometimes be a bit unclear for the uninitiated. Here's an example of an LG refrigerator schematic:
The whole picture is a bit much, but notice all those bubbles popping up around the schematic? Let's pick one of those and focus in on it. Here's one coming off the sub PCB:
I've got another scenario for you, taken right from the trials and tribulations of an Appliantology tech. Here's the situation: you're working on a top-load washer, and whenever you try to run a cycle, the tub doesn't move and the motor just hums.
Right away, we have a decision to make: do we go ahead and tear apart the machine to take a look at the wash motor? After all, there are a number of mechanical failures that could cause these symptoms. Maybe we should just go ahead and get our han
What would happen if you took a 240 VAC outlet and swapped the terminals around? What effects might that have on the machine that's plugged into it?
That might just sound like an interesting thought question, but it's an issue that more than one tech here at Appliantology has had to deal with. So let's pull out a schematic as an example and start drawing some lines!
By the way, the process I'm going to walk you through is something any tech should be able to do: puzzle out how a circui
In this two-part Master Samurai Tech webinar series, we explore the nuances of sealed system diagnostics. Specifically, we're covering the nitty-gritty of applying our understanding of sealed system thermodynamics to real-world sealed system failures, such as refrigerant leaks, overcharges, and inefficient compressors.
Sealed System Diagnostics, Part 1
Sealed System Diagnostics, Part 2
Topics covered in the first part include:
Sealed system temperatures and pressure
Happy Thanksgiving from all of us on Team Samurai!
I'm thankful for a year of Appliantology members keeping each other sharp and preventing us all from devolving into turkey techs. It's due to this fine community that we're not the ones in the oven.. this time.
Here's to another great year!
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
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
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
How does a dryer dry without a vent? Why is there a sealed system in this dryer, just like what you would find in a refrigerator? How well does this model dry clothes compared to a conventional dryer?
All of those are questions we answer as we explore Whirlpool's hybrid heat pump dryer. In this thorough rundown of the machine's key systems and components, we cover topics such as:
The function of the sealed system in this heat pump dryer
How this dryer condenses moisture rathe
One of the best things we can do to sharpen our skills as techs is to learn from other techs' experiences. There are a number of ways to do that, but the way that's both most convenient and lets you learn from the greatest variety of techs is searching the tech help forums here at Appliantology.
Appliantology has been on the web for 20 years now, and over that time the site has amassed a library of technical knowledge that is unmatched anywhere else. As a member of Appliantology, all of th
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
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
These aren't your grandma's ignition systems -- these are systems that use a DSI (Direct Spark Ignition) board, and that means you've got algorithms involved.
If you want to troubleshoot a DSI system, you need to understand this algorithm -- it's how the board thinks. Is the DSI board not sending any voltage to the electrodes? Well, it might just be in lockout mode after a failed ignition, meaning the problem lies elsewhere than the board. You can't troubleshoot a system if you don't know h
Techs as a community have developed some bits of jargon that serve as shorthand ways of describing specific technical situations. These phrases are useful for saving ourselves time and breath, but sometimes the exact definitions get blurry. Even worse, sometimes the way that the phrase sounds gets confused for a description of the actual science/physics behind what's going on, leading to a variety of "tech myths". Let's clear up a few of these terms.
"Failing under load"
This a situat
In this webinar recording for the ages, the Samurai explains everything you need to know to run a successful service call, minimizing return trips and maximizing profits. He covers the steps you need to take before the call and how you need to think while on the call. All of this information is neatly and concisely presented as The Samurai System for Service Call Excellence -- a must-know for any tech who wants to make the most money for the least headache.
The topics covered include:
Take a look at the defrost circuit on this Whirlpool refrigerator:
Looks pretty standard -- there's just a defrost heater and a defrost terminator in the circuit, and voltage is supplied to the circuit by the control board.
But what is the purpose of the wire marked in green that tags off to J1-3?
If you look closely, you'll see that that pin on the control is labeled D-SENSE -- so that's a sensing line. This means that the purpose of that wire is to give the control board i
Reliable income is something all techs want to achieve. But to have consistent profits, you have to perform consistently on service calls. While we all might like to think of ourselves as repair cowboys who can head out on every job half-cocked and still get it fixed right, that's just not reality. The way to achieve the most consistency possible on service calls is by using systems.
A system is coherent set of standard operating procedures (SOPs) designed to achieve a specific objective. I
@fillthebarman ran into an interesting problem the other day: he had a stacked washer and dryer where the washer could only be run when the dryer was running. How is this possible? Brother @sh2sh2 had the answer:
A brilliant piece of insight, and precisely what turned out to be going on here. But how does this happen, exactly? Let's look at the schematics. Here's the washer:
As you can see from the circled bit, the power supply for the washer comes right from the dryer's connec
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