Hi, i'm brian with hvac school thanks for watching this video, which is with guest instructor ty branuman tai, is one of the most interesting, exciting and dynamic educators in the hvacr space. He was kind enough to come down and visit us and he visited our apprenticeship program in eustis florida at lake technical college and taught the students about a compressor diagnosis. And specifically, he talked about a compressor diagnosis scenario that he had run into earlier. In the day.

Riding with one of our service technicians, so i think you're going to find this to be applicable. I also added a link to ty's channel down in the description, so please go to ty's channel check out all of his amazing videos on youtube and subscribe to his channel. He truly is one of the most dynamic and interesting educators in our trade hope you enjoy. So if i have electricity with very little resistance between line one and line two and there's a whole lot of push, but very little resistance, how fast those amps gon na flow very fast so fast that it trips the breaker immediately so they're flowing from line one To line two with very little resistance, electrons are going to flow super super fast as fast as they can and what happens when you move electrons really fast, it gets hot right, it gets hot.

So, what's happening, though, is this compressor inside shorted out the electrons are flowing instead of going through a circle through all the windings? It was going from line one to line two too fast to save the house. The breaker trips right, that makes sense. People say all the time you don't own out, compressors, that's a perfect example of how we can oh map that compressor without having to do any math. We just owned it out and said hey, if not knowing what these numbers should be.

They were this one set. Is really really low, extremely low? We have a breaker tripping, we have low resistance. Do you see a connection? It was shorted out now, you'll see people say. Oh, i have a bad compressor, but i always want to know how.

Why is it bad? It's not just bad, it's like, oh, it stole a carton of eggs and it was hungry or what made it bad, it's not just that it was. You know it called somebody a name and offended somebody. What made it bad i want to know. Did it ground out? So if we were to check line one line, two sorry from line one to ground or line two to ground, with continuity with the power off and continuity, then it's grounded.

That means from one of these terminals to metal i'm getting flow. Does that make sense, remember when you pull that compressor out and we had all those windings in the very top, all those windings, the electricity supposed to flow through all of those different coils if it's grounded? That means one of these windings. I'm able to see it here, nope see, look in there and see the windings if it's grounded it's touching one of those windings and the metal casing. That's grounded that it's also that's a bad compressor.

In this case it was not grounded. What happened was instead of electricity going through all those different coils? Here's an example, so instead of electricity touching from these wires to the metal grounds, it was instead of going through all these loops. It was taking a shortcut, so it was just going across this one across that one or maybe it's going through every fifth one: the insulation, the varnish on here, melted when the varnish melted instead of electricity having to go all around the loop. It takes a shortcut and just goes across, so this compressor for some reason it started overheating and these windings, the insulation varnish and these windings started to bake off when it bakes off electricity can take a nice little shortcut now they're moving faster, which makes even more Heat which bakes more of the insulation off, which makes more of a shortcut which means more heat.

You see the pattern and domino effect. That's exactly right. Until now, electricity is flowing so fast from line one to line two that it's tripping, the breaker, that's what we had today. This is the first method we used to check it.

So here's another method. Now, there's a lot of things. You can own out right. There's several things that can be shorted.

Here's the next method, pull the plug off of the compressor, make sure the the plug is not touching. Anything in this case there's three wires, which a little bit more dangerous. But if you have the plug, you leave the plug out. So if i leave this plug out - and i was to turn the unit back on what would happen, it shouldn't trip nothing.

What do you say? The fan motor would come on? Yes, don't leave me hanging here? Yes, the fan loader would run the condenser fan motor is running, but what else will be running air handler? The blower be running? The transformer would be uh, dropping its power down your outdoor family, everything, but the compressor. But everything stayed on it didn't trip the breaker anymore. Now, there's a third thing that we checked so now. We know the meter says this is shorted.

We unplug this and now it's not tripping the breaker anymore. So that also confirms we have an issue with the compressor. Is there another thing that we can check? Nothing is stripping the compressor after you unplug that from the compressor it's another thing we can confirm on this compressor to see hey. We have a bad compressor.

I don't want to tell the customer hey. The compressor has been bad well plug it back in if it trips the breaker, we know for sure. But what else can we check? How do we know if maybe it went bad because there's a refrigerant leak, you check from a line to the compressor and if it bits, if you have continuity and it means yeah, we could check and we did check that means you're grounded. Think about refrigerant.

The refrigerant side, let me give you guys think about the refrigerator. What happens if you replace this compressor? Is there any way to find out if something else is wrong, if the new compressor is going to be blown to bits too, you've been here before, you've got the correct amount of refrigerant yeah, but you can't because the pressure's not running, but the key thing is: Do you have any refrigerant at all, so you put your gauges on. Do i have anything at all what if it shows zero? What would that tell you? You have a leak, yes and leaks aren't just in supermarkets right. We also end up with leaks in our residential systems.

Oh somebody got it, i'm impressed good, so we also know with leaks in our residential system now, if it had a leak, that would tell us what killed the compressor. In this case, we had refrigerant, but when my my guy took his gauges off, i had him do something particular after he took the gators. They were probed. There's no refrigerant left oil.

That's left! I had him, do something. Can anybody guess what i had him do with the gauges after you took him off? You got the sniffles sniff test, yes good to sniff test. Why do you think we would do that not to confirm a leak? I like how you're thinking? No, i love that you're answering these questions. I love that just no, there wasn't a leak to see if the uh, we don't think, there's a leak.

The oil's been uh degraded, yes to check the oils if it's been degraded, also the refrigerant. So what we did is we took a little smell of it and it had this pungent smell to it. The pungent smell tells us hey. We have an issue with the refrigerant oil.

It was a burnout. Well, to recap: the compressor shorted it wasn't grounded, but it was shorted from run to common from start to common. We were still okay, but from run the con we were shorted. So when it shorted out, it ended up also burning the refrigerant or burning the oil.

That's also when it was being shorted out trip the breaker, so this compressor was dead. It's not just that. We checked it. It was tripping the breaker, it's like hey.

We want to know why we want to confirm so we confirmed it with our meter. We confirmed it by isolating the component unplugging it everything else is not working. Then we also checked the refrigerant inside and found out hey. We have an issue because the refrigerant smells bad, it's a burnout.

So now, when i go to the customer, it's not like uh. Your compressor's bad, no, we know without a shadow of a doubt, hey this compressor is bad. That way, this guy doesn't come back behind me and be like oh hey. There was just this loose wire because i've seen that i've seen the plug over here.

The terminal burn off and somebody said: oh, you have a bad compressor. Then i come back put a terminal kit in there and they have another five ten years out of that compressor, i got a new customer. So if i'm going to condemn a compressor, i want to know that burst's not going to come in behind me, be like hey ty. I just took your customer now.

I have this unit this customer forever, because i fixed our terminal. We confirmed with multiple different ways to know hey. This compressor is 100 dead next question: what would you recommend to the customer? Let's give you a scenario. The unit is 23 years old, the condenser fan motor is rusted, coils are corroded.

It's next to water fan. Motor is coated in all kinds of growth. There's rust everywhere, there's uh the con. The capacitor has been replaced before they didn't replace it correctly.

It's laying on the side on top of the swollen compassion, it's already bad heat kits, are covered in growth, contactors pitted. What would your recommendations be replace the unit that would be my recommendation, but hey. I recommend that we replace this unit. The customer say can't you just replace that part, and you say yes, but you need to warn them.

We could do that, but here's going to be the price and there's going to be a lot of other risk involved me as a company owner. I would say: no, there may be somebody that will. I will not do that work because here's what you have you spent so much money on that compressor, and now you put that compressor and there's a leak six months later or a month later, or the fan motor goes out now a week later, even though you Did this work all this work, they're saying hey, i paid you twenty seven hundred dollars. I paid you 2500.

I paid you money and now it's broken again, that's in their minds. So i'm saying hey me and my now you ask your company what's right for you what they want to do, but me and my company i'd say i don't want to be responsible for just replacing that compressor. You may find somebody that can but to me i'm like hey. If you want to do something cheap window units, you can't tell your customer that all the time, although i have before anyways the moral of the story is short, we were talking about yesterday.

Electrical current resistance and that job today played right into that. It was a beautiful beautiful scenario and i was thinking. Oh, i can't wait to get the class to talk to you guys about it, thanks for watching and big thanks to tai for doing this with us and being willing to have it filmed and shared on our youtube channel. Like i mentioned before, please go down into the description and click the link to ty's channel and subscribe to his channel.

I think you will find it to be really great content and we will catch you on the next video thanks for watching our video. If you enjoyed it and got something out of it, if you wouldn't mind hitting the thumbs up button to like the video subscribe to the channel and click, the notifications bell to be notified when new videos come out, hvac school is far more than a youtube channel. You can find out more by going to hvacrschool.com, which is our website and hub for all of our content, including tech tips, videos, podcasts and so much more. You can also subscribe to the podcast on any podcast app of your choosing.

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