Latest / The Refrigeration Mentor Podcast / Episode 378. Field Stories: Compressor Failure, Case Freeze-Up Troubleshooting, and Electrical Safety

Transcript

Episode 378. Field Stories: Compressor Failure, Case Freeze-Up Troubleshooting, and Electrical Safety · The Refrigeration Mentor Podcast

• 0:00
  Trevor: What's up? Welcome,
• 0:01
  Andrew: that was, that was a, that was a fun one. I, I walked in and the machine, that compressor was hot. I mean, it was, it was screaming pretty good. Isolate it, shut it off. And then I knew there was something wrong because your, your compressor, when you got your head.
• 0:02
  I got, I need to know, I need to know what happened to it. And that helps me diagnose how to fix the problem. 'cause if I don't, it's just gonna happen again. So, isolate it. Got the gas out of it, pulled the heads off. And as you could see here what you for the people that are not, or just listening the very first picture, if you could get on top of the head so this is I just took the top of the head of the compressor out and then I'll just by this photo here, you could see on that discus valve there's chunks in internally in there. I was like, oh man, I definitely, there's something internally going on.
• 0:03
  So, yeah. And then, and then I pulled that the valve plate off, and then that's when I got into it. And you could see chunks of the discus valve and in the cylinders and, and all the scarring that occurred into it. So this compressor, it's honestly shot. The pistons still go up and down. You could still push down on the, there's no really like play when it actually connects to the connect, the connecting rod to the crank.
• 0:04
  Trevor: Like, so that to me, I can see copper in there. So what's happening there is that this copper plan, this copper is getting, it gets put into hut, parts in hut, parts into the system, but right inside here. You can see that there's copper in there. So now that the copper's in there, as the piston goes up and down, I bet you if you pulled these off, you'll see a lot of wear.
• 0:05
  'cause the gas carries that oil, that mist through it. And now it's, now it's getting, getting on the, some of the pistons and as well as it could be being blown up like through here, like these little, like having that blow by happening. So for sure, and I noticed it definitely on this other one, like real, right when you took off the top, like if you take a look right at that color, like I, lots of people that's just oil, right?
• 0:06
  But I'm, I'm getting an oil tested. I'm really curious, like what I'm gonna find in this oil. It's, this rack is definitely old. I mean, it doesn't even have a, an E two or any, any,
• 0:07
  What was the superheat supposed to be? What were your pressure? Where did you put your pressure gauges at? So, and over time you'll get better with these checklists so they can actually pinpoint it a lot quicker for you. 'cause if they, the more information they have, the, these guys are experts, the more information they have, they can at least point you in the right direction where to start.
• 0:08
  So that's, that's course There was another question. I think it was right up here that he said oh, I need to learn how to clean the screens. Great question. Not everybody knows how to pump down a circuit if you're new, you know, so, andrew, what, how do you, if you're, you need to cha change a screen.
• 0:09
  Circuit. Now you can go down into your cases and start pulling the screens off of the TX vs. Since you're, since it's already pulled and you're, you know, you feel like there's a potential of a screen being plugged on that one TXV, you're already there. Do 'em all, it's gonna save you. 'cause you know, as soon as you get that one going, maybe a week later, the next one, literally that you worked right next to might be plugged up.
• 0:10
  Trevor: Yeah. When you're, yeah, you're upgrading it. Don't get the same one, get one where you can clean the screen, you know? 'cause you gotta replace it at, at that point. Yeah.
• 0:11
  Trevor: Yeah. One of the things for sure if, like, if you're, you guys are doing this like behind here, I don't know if there's baffles back there. Like in this case, if I had the model number, we can look up the model. So like, this is all frozen up here.
• 0:12
  Like why is this, why is that? Is that happening because of this once it is super cold. So the thing is, is as Eric says as well, why are we, why are you running it so cold as well? Like meet, you have to be below your SST is gonna be below freezing. 'cause you want to keep the, I think around 29 Fahrenheit, like minus one Celsius.
• 0:13
  And I use, honestly, when I'm trying to find it, 'cause sometimes it's hard to find that information. I use ai, I use AI to pull up my PDS on, on cases. And man, it's a, you just say, I, it's this case manufacturer, here's my model number, and it literally pops up all that information that I need. And then, and then I click on that PDF and it's right there.
• 0:14
  There's still ice. This looks like still ice in there. So maybe it wasn't done. He took a picture of it. But you gotta make sure every ounce of ice is out. And what else did I wanna look at? So see these suction lines, this is, this is an issue. You see how the suction lines are pointed down? That's a major issue.
• 0:15
  This liquid can, or this one here, whatever. When liquid's traveling down here, that liquid will now go into this case. Then all of a sudden this case is gonna be like satisfying right away. And you're like, why is it satisfying? The temperature's not right and then all of a sudden this one starts to freeze up.
• 0:16
  Andrew: is it? Yeah. Yeah. That's awesome. This is why we do it right here. This is great.
• 0:17
  Trevor: You know what I mean? But over, if, look, if we look over here, and I know it's hard to see, but look it right here.
• 0:18
  Andrew: Yeah, I mean, I, I would be looking to see if that's even sealed and test it, see if there is airflow coming out of it. Just to be a hundred percent sure that is correct. Then I would be caught. If it is bypassing, then I would be looking into y and that could be the, somebody installed a new coil and put it in a little bit wrong, causing it to be, you know, bent in a certain way that's causing that lift up.
• 0:19
  But yeah, I mean that, I mean, with it icing up that bad, it looks like there's definitely a defrost issue. Is it long enough? Is there, is the quantity enough? Is the solenoid completely shutting down if it's a suction stop or a liquid line solenoid? I mean that, it looks like it's a, it's a whole, it's not an individual circuit problem.
• 0:20
  Now I don't have to add either a heater. You can reduce the cost and I've seen this lots of times and then all of a sudden it starts, it, it's something that freezes up every six months and people think it's normal. That is not normal. Ion not freeze up once a year, not especially once every two months.
• 0:21
  And honestly, that's where I would be going with this. Just to make sure we are inspect with the manufacturer. And then, Trevor, you did mention something earlier that does put a factor in it. Is the humidity in the store, if it's super high humidity is gonna be problem, or if the temperature in the, in the store is off is gonna be the problem.
• 0:22
  So how do we, we can't even get any airflow, so we're not gonna increase that temperature that much. So this is, it would be good to see if we, we had the last month of data and then we look at how it's going. Because the temperature here, where are we going? We're going from. 24 up to almost. So there's a big range there.
• 0:23
  So if you could see like tomorrow or something when it's been running and it's down to temperature, it's been having a normal day of work and, and just see how the graph is looking.
• 0:24
  Know what I mean? And that's what a lot of people are taught when they're, oh, it must be, I mean, you open it up or close it off. This is, that's the last thing there. So he is doing a good job asking the questions. I love that. I love that. So keep asking those questions. And this is, this is how we can help you get better as a technician out there, because we didn't know, you know what I mean?
• 0:25
  And I got so fixate fixated on that. I, I lost track of what I was doing 'cause I didn't understand why I had 2 0 8 to ground on a two 40 volt circuit. So, I called the, called my boss and he was trying to explain it and I was like, that doesn't make any sense. He says, that's not your issue. That's fine.
• 0:26
  But that's how you get that to ground at that point. So don't be alarm of it. It's just, it's there, it's normal when you're talking about a delta transformer instead of a y transformer. The only thing is though, when when you're installing stuff, make sure you have. When your one 20 volt appliances or whatever it may be, make sure you have one 20.
• 0:27
  'cause I'm changing in a, a evaporator fan motor. And I, I noticed that two 40 or 2 0 8 to ground and I was like, oh, I gotta, I gotta share this because I, I got trapped in the cycle of what is this? There must be something wrong when in reality that's normal.
• 0:28
  Go down to my truck and have my meter and check before I cut them. And it's something that it was a hundred percent my fault. You can't blame anybody else. Like even if they say it's off, that's not their responsibility. It's your responsibility for your safety, not anybody else's. And like I even say in, in the thing, like I was, I, I was mad in my head at that service manager, but when I look back at it, definitely now that was a hundred percent my fault.
• 0:29
  Be safe. That's what we're saying here. Any final thoughts for the community guys?
• 0:30
  We're gonna start getting Louis to upload them into the community so people can go back and rewatch them. Nikki always thanks for showing up every week, so I really appreciate that.