Here's the problem scenario:
The customer's refrigerator has stopped running. You take a look at the start device, and it's completely burnt out -- enough so that you can see that the plastic housing has melted. You swap it out for a new start device and...
Still nothing. In fact, a quick voltage measurement shows that the control board isn't sending voltage to the compressor. Now the board needs to be replaced, too.
So what happened here? Did the start device just short out and t
A tech is troubleshooting the power supply for a Maytag dishwasher control board, and he finds some interesting readings. Using a LoZ meter, he reports finding 120 volts at the outlet and at the control board. But strangely, he also has 48 volts on neutral. What gives?
In our latest webinar, we unpacked all the electrical know-how and troubleshooting mojo that goes into properly diagnosing a problem like this. To figure out what went wrong in this troubleshoot, you have to answer the follow
Here's something for you sharp Appliantology techs to puzzle over: what in the world is the circled symbol on this schematic?
Is that a wiring harness? Maybe this diagram's strange way of showing a splice?
To figure out what it is, we've got to have a functional understanding of how Electrolux likes to design their water valve circuits. Let's look at a similar configuration that's drawn differently.
There we have it -- on this schematic, the engineers decided to throw
Happy Thanksgiving to all the Appliantology Brethrens!
I'm thankful to be part of a community of such sharp techs who are always willing to help each other out. Here's hoping you're popping open a cold one with the family and enjoying the things that matter most.
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
Here's the situation: the tech is working on a dryer that keeps blowing its thermal fuse. The tech has already replaced the fuse once, and it's now blown again. What could be causing this, and what's the best way to tell?
We'll start by looking at the heater circuit -- an essential step in any troubleshooting plan.
Pretty simple stuff. Just a cycling thermostat, a centrifugal switch, and a hi-limit thermostat. The thermal fuse that keeps blowing is the one in the motor circuit. I
As control boards, and especially multiple-board configurations, become more and more prevalent in appliances today, we need to keep our troubleshooting skills sharp and adapt. So what troubleshooting strategies should you apply when you're dealing with a computer board?
The good news is that you don't need to be a computer geek to work with boards. You just need a troubleshooting strategy for dealing with them, and you need to understand how they operate on a basic level. That's what the S
Bimetals show up all over the appliance world in all kinds of applications. Resistive Temperature Devices (RTDs) are widely used in ovens and ranges and are commonly called "oven temperature sensors." Both are devices that respond to temperature, but beyond that, they work completely differently and serve different purposes. Watch this short excerpt from one of our many technical education webinar recordings to learn all about these devices!
The full webinar covers all the common
Imagine you're out on a call, and you run into this:
As the picture says, the dryer runs like this. And even weirder, when you correct the wiring, it stops running.
Take a minute to think, then see if you can answer this pop quiz:
1. How does the dryer run in this configuration?
2. What's wrong about the wiring in this configuration?
3. Why does it stop working when you correct the wiring?
4. What one test could you do that would prove your hypothesis about th
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
When you need to test a component, do you always need to just resign yourself to tearing apart the appliance until you reach it? Or is that a waste of time and energy (not to mention unnecessary liability), when you could be working smarter, not harder?
Let's say you're working on a Samsung dryer, and you want to measure the thermistor. You know the ohm spec (unfortunately they don't give you voltage drop), so all you need to do is get your meter probes on it so that you can compare. Is you
Brother Scott-afl ran into some unexpected trouble when trying to extend the defrost cycle on a Samsung RF28HFEDBSR/AA refrigerator. In his words:
Two puzzling things here:
First, why the difference in the error code reporting? It's a minor point, but that E/C difference seems odd.
Second, why is the procedure for extending the defrost not working, despite multiple attempts at following the instructions in the manual?
Both of these discrepancies boiled down to one thing: po
Our online appliance repair training site, MasterSamuraiTech.com, will have a few hours of downtime tonight (Monday, October 26, 2020) starting at 11pm eastern time as we install our brand spanking new website.
We will post any important updates right here at my blog.
If you are a current student, here's a quick overview of what you will experience once the new site is up and running.
UPDATE: The new site is up and running! Check it out for yourself.
In this excerpt from one of our many in-depth technical webinars, the Samurai breaks down in just a few minutes what causes ghost voltage. He'll show in simple terms what the term "capacitive coupling means, as well as how to do your voltage measurements correctly so that you'll never be fooled by an open neutral again.
Want to watch the full version of this webinar, along with 50+ additional hours of practical technical education? Click here to become a premium tech member today.
I've seen a few guys around the forums ask the same question: are surge protectors (also called surge suppressors) safe to use on refrigerators?
Best I can figure, this question comes from folks mixing up surge protectors with AFCIs and GFCIs (you can click here to read about how those devices work). But it speaks to a general ignorance of how surge protectors work. Well, why don't we fix that?
The reason surge protectors exist is to block voltage spikes -- those are large spikes in th
Picture it.
You're walking into the service call of a long day, but you're feeling good. You've got your tools in hand, you've done all the prediagnosis; you're gonna kill it. The customer lets you in, and while chatting affably he begins leading you to the appliance.
You can't place why, but a dark cloud of foreboding passes over you. You push it aside, but the feeling only grows. He's leading you downstairs now, into the basement. It's dingy down here -- clutter everywhere.
No,
Whether a control board in an appliance is simple or sophisticated, there's one trick it has to pull off: switching high AC voltage using low control voltage. They pull this off by using relays or triacs, devices that all of us are at least passingly familiar with.
But how do these very common control components work, exactly? And how is troubleshooting a relay different from troubleshooting a triac? That's what we'll look at today.
Relays: The older and simpler of these two devices, r
Samsung has developed something of a reputation in the tech community, and not necessarily the most flattering one. Many consider the brand to be overly-complicated and impossible to troubleshoot, and some refuse to work on these machines at all. But is this attitude really warranted?
All appliances everywhere work on the same principles, and Samsung is no exception. The idea that Korean appliances like Samsung and LG somehow work differently is pure mythology, and this short excerpt from o
Every split-phase motor needs a start device, and split-phase compressors are no exception. There are a variety of start devices out there for compressors, and it's vital for your troubleshooting that you understand how they work. In this short excerpt from a longer webinar recording, the Samurai steps through the differences between relays and PTCs, laying the groundwork for differentiating between these devices in the field.
If you want to learn more about the technology used in modern re
Ever seen a capacitor somewhere in a split-phase motor's circuit and wondered what exactly the point of that thing is? That's what we'll talk about in this blog post.
There are two different types of capacitors in split-phase motor circuits: start capacitors and run capacitors. Each type has a different set of parameters and serves a different purpose. But before we get into these specific types of capacitors, let's take a quick review on capacitors in general.
Capacitors aren't compli
There's more than one way for a 3-way valve sealed system to be configured, and if you want to troubleshoot these machines right, you've gotta know the difference.
In the full webinar recording, the Samurai runs through 3-way valve operation and dual evaporator systems in detail, using Samsung technical documentation for reference. It's not one you're gonna want to miss!
Click here to watch the full webinar -- only available to premium members!
For those of us techs based in the States, it can be easy to think that electricity just "happens to exist" as our familiar 120/240 volt split-phase power. But that's only one of many forms that electrical power can take. It can come in a variety of voltages and phases, all depending on what standard a particular country or region decided upon.
Let's step through the most common of these. There are two that North American techs are likely to encounter: the typical 120/240 volt split-phase t
Many techs are intimidated when it comes to troubleshooting control boards. After all, we're talking about computers here -- computers that just so happen to run appliances. But as complicated as that may sound, control board troubleshooting really boils down to just three things: measuring your inputs, measuring your outputs, and understanding the board's algorithm.
Let's start with inputs. Input just means anything, be it a power supply or some information, that the board receives f
Two of the most common circuit protection devices we'll see on outlets or circuit breakers are AFCIs and GFCIs. But what exactly are these devices, what do they do, and what are the differences between them?
The Samurai answers these questions in this short excerpt from one of the hugely enriching webinar recordings available here at Appliantology. Want to watch the full webinar and learn the whole scoop on these protection devices? Get access to it and 50+ hours of on-demand recordings by
We've all changed countless ignitors in gas ovens, and any tech worth his salt knows that the definitive way to detect a failed ignitor is with a current measurement. But why does low current through the ignitor cause ignition to fail? Where does that current spec come from?
In this short excerpt from one of our many technical webinars, the Samurai explains the mechanism behind how these gas valves work. Not only will it give you a clear idea of the technology behind these common parts, but
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