We encounter diodes in a variety of situations, such as in certain refrigerator water valve configurations. If you want to be able to properly troubleshoot these setups, you need to understand the underlying technology of diodes. How doe they affect the circuit around them? And how do you test them?
These are the questions that we answer for you in this short video introduction to diodes. In just 6 minutes, you'll learn about how they work and how to properly test them. Plus, you'll learn a
Whether you were aware of them or not, Hall effect sensors are everywhere. Any time you see a motor on an appliance with any kind of RPM feedback or speed signal, there's a Hall sensor on that motor. As with any ubiquitous appliance technology, it's important for us techs to know how they work. A deeper understanding of the technology means a deeper understanding of how to troubleshoot it.
So: what is a Hall sensor, and how does it work? These are semiconductor devices, so as with most elec
A tech here at Appliantology recently ran into a dryer that would not start. As he explains in his post:
After he's already changed the start switch, what could be the problem here?
Well, as several techs in that topic helpfully pointed out, even if you replace the start switch itself, there is a common failure of the plastic button itself that prevents the switch from being actuated.
As esteemed Appliantology brother Rhubarb Tau explained:
Here's a picture of what that
A tech here in the Appliantology forums encountered a GE dryer that was completely dead -- no lights in the UI and no response of any kind. Here's how things went in his words:
Always a bummer when you replace an expensive part and it doesn't resolve the problem. But maybe we can triage this and figure out what could have been done to avoid the unnecessary board replacement.
Here's the schematic for this stacked dryer:
Let's focus in on the places where our tech did his tr
Got a fun exercise for you today: let's use our electrical and schematic know-how to figure out how a circuit works in a schematic that leaves out a lot of useful labelling.
The circuit we're interested in is the one labelled Door safety interlock.
Based on its name and its context within the schematic -- it gates Line to a number of loads elsewhere in the appliance -- this circuit contains the door switch and the door lock. But how exactly does it work? We can assume that the sw
It's about time I talked about this in one of these posts -- the AI revolution is upon us.
Okay, it's not quite Skynet yet, but it's still spelling disaster for a lot of different jobs.
Some are already halfway out the door, like many repetitive and administrative jobs: customer service, scheduling, and data entry, to name a few.
But they're just the start. Many other positions that are often thought of as requiring more skill and education are prime for the silicon harvest:
Here's a weird one for you: how does this dryer run with the neutral wire of the pigtail completely disconnected? To find out, watch this short, 7-minute excerpt from one of our many full-length technical training webinar recordings.
In this video, you'll learn the answer to questions like:
What is the difference between 3 and 4 wire dryer cords?
Why should neutral and ground be separated?
Why is the dryer able to run without neutral connected?
Give it a watch a
We've got a tricky one for you today: a Frigidaire-built Kenmore electric dryer that only runs on heat cycles. If you set it to a timed or auto dry, it runs just fine. But set it to air fluff, and you get nada -- no motor rotation, no nothin'. Sounds like a bad timer, right? That was our first thought, too. But like any good tech should, we covered all of our bases before jumping to conclusions, and what we found was much more interesting...
We'll start by analyzing the circuit of the motor
I wanted to highlight a recent topic in the Appliantology forums because it showcases a few good teaching points -- and because it had some fun pictures.
Here's the initial setup that the OP gave in his post about an electric dryer:
There's a very important tidbit in there: someone other than the tech did work on this previously. Maybe another tech, maybe the customer -- we don't know. We'll circle back to why that's so important.
The OP continued:
So, over the course of
How do you troubleshoot a dryer that heats all the time, even when a cycle isn't running? That's exactly the scenario that a tech here in the Appliantology forums ran into, and even after replacing the timer multiple times, the problem persisted. Let's get to the bottom of this.
Here's the schematic, with the heater circled in green.
Something important to note about this dryer: it's an old-school dryer with a mechanical timer. No electronics in sight here!
What we need to f
Inverter compressors can run really smoothly and quietly these days -- so quietly that it can be hard to tell if they're running at all, let alone if they're running properly. So if our ears and hands can't tell us what's up, what do we do to test these compressors?
Time to apply our brains and our meters: we're going to use the schematic and some simple electrical measurements with our ammeter and our multimeter to know if the compressor is running.
Step 1 is to use the schematic to
Reading schematics is an essential part of troubleshooting, but it's not always clear how to break down a circuit into understandable bits. Is there an easy rule of thumb for identifying what component does what and how to go about testing it?
In this excerpt from one of our many full-length technical training webinar recordings, you'll learn exactly that! In addition, we'll show you how to break down a seemingly tangled schematic and identify loads in series vs. loads in parallel -- all in
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
The temperature sensors used in ovens, which are devices called RTDs, don't vary too much between brands and models. There's something of an industry standard for RTD specs that you can generally rely on, even when you aren't given the specs explicitly.
However, Frigidaire has left a booby trap in the form of an RTD with unique specs in some of their ovens. What's more, this difference isn't even properly reflected in some of their tech sheets. They've got incorrect specs!
Want to know
Some seasoned Appliantologists had a good topic in the forums where they posted some warnings for posterity about some easy-to-solve, but nonetheless tricky gotchas that you can encounter when working on laundry appliances. I figured they should be archived here so more people can keep these simple tips in mind.
First up, Brother Coley described an issue he encountered that had him scratching his head:
The root of the problem? Well...
Don't worry, Coley -- we've all been there
"Ohms lie." It's become a popular phrase in the tech community, but what does it actually mean? Should you never do an ohms measurement? Are they completely worthless? Or is this phrase just another example of tech mythology?
The answer is more complicated than any of that. Let's run through a quick example to demonstrate. This is an old-skool Whirlpool gas dryer, just like they were cranking out left and right in the good old days.
Now, our scenario is a simple one: when we run
In this excerpt from one of the many technical training webinar recordings available to our members, we cover two tricky areas that have tripped up many a tech: deciphering an unclear schematic, and decoding a convoluted customer problem description. Both of these are essential skills for any tech, since if you mess up either of these steps, the entire rest of your troubleshooting will be thrown out of whack.
The troubleshooting framework that we're using in this video is our patented Ten-S
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
Special guest presenter Mark Williams will show you how easy it is to diagnose temperature problems in the newer electronically-controlled refrigerators and how to do it right the first time.
We'll show you examples from Samsung, LG, GE, Whirlpool, and Electrolux. You'll see that they all work the same way.
You'll also see how to accurately test thermistors from the computer control board and you’ll learn the difference between resistance and voltage drop when it comes to testing the
Reading timer charts may just seem like an old-skool skill for a bygone era of appliances, but there are still plenty of these old workhorses around that need troubleshooting. Plus, analyzing these circuits teaches you a lot of schematic mojo that is useful in all areas of appliance repair.
In our latest Live Dojo workshop, we worked through how to read this timer chart and schematic in harmony with each other. You can't understand the schematic without the timer chart, and vice versa. Topi
Sometimes, manufacturers don't write out schematics as clearly as they should. In cases like this Frigidaire cooktop, the way that the relays for the simmer function are drawn is downright obtuse.
In our latest workshop webinar, we broke down the function of this circuit and really understand how it works, bringing our electrical and technical know-how to bear to make logical deductions about the circuit.
Did you miss the original webinar and want to watch this webinar recording? Click
A tech in the Repair forums here at Appliantology was trying to troubleshoot an inop evaporator fan motor, and he had some trouble figuring out what to make of his measurements.
Let's take a look at the schematic in question and see if we can clear up the confusion.
Oh boy, that's a tangled one! I've circled the refrigerator evaporator fan motor in question.
We can tell a few things about this fan immediately. The Vcc and GND designations show that this is a DC fan motor. Vc
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
We had a great webinar this past Sunday all about troubleshooting a Thermador wall oven with a cooling fan that wouldn't run. Lots of vital tech know-how covered in this one, like how to structure your troubleshooting flow, identify loads and switches on schematics, and perform useful and meaningful tests that will lead you to the correct solution.
In this short excerpt from the recording of that webinar, we talk about using the schematic to identify EEPs for your testing -- no unnecessary
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
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