How Improper Handling and Low Airflow Kill HVAC Compressors Without Warning with Glen Schwarzman
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AC SmartSeal, the professional's choice. What's up, guys? So we got Glenn Swartzman from Copeland, and this conversation is generalized. We talk about a few different things, like putting 410A into an A2L unit because we have a problem getting one of the refrigerants currently because there's a shortage. We also talk about oil return, and we talk about single speed versus the modulating type systems as well. So it's a very generalized conversation.

conversation, but there's a lot of educational talking points here. And I know you guys are going to learn something from this. Let's get to it. This is the HVAC Know It All podcast. I'm your host, Gary McCready. This podcast is sponsored by Master. And if you guys are looking for additional training, commercial and residential training, reach out to your local rep because here in Ontario and even out West, they have training facilities and they are doing consistent

and constant training on different things, commercial and residential. So check them out, guys. Check out master.ca. Welcome to the HVAC Know It All podcast, recorded from a basement somewhere in Toronto, Canada. Your host and HVAC tech, Gary McCready, will take you on a deep dive into the industry, discussing all things HVAC, from storytelling to technical discussion. Enjoy the show. All right, Glenn. So

We were discussing off the air, and I was telling you, like, through social media, I see this often. Not often, but I see it once in a while. There's a shortage of refrigerant out there. And I think that it's quite apparent within the industry that one of the A2Ls, the 454B, is...

In demand, because there's not enough of it. Now on my social medias, I've seen people talking about adding 410A to top off or just using 410A in general to fill that system up to get the customer going and people are saying it's worked.

Just give me your general take on that, if you don't mind. Yeah, thanks, Gary. Thanks for having us. And I mirror your comments with regard to R454B and what I've heard in the industry. But here at Copeland, we design certain compressors for certain refrigerants. They are designed, tested, and qualified for a certain refrigerant.

So whether it's a full system charge or whether it's a top out, we discourage that very much because we have no performance specifications. We have no electrical specifications.

For a compressor model with a different refrigerant than what it was designed for. So, I mean, because it's not designed for it at the factory, you can't promise it's going to work properly. Copeland can't specifically back up any sort of warranty or anything like that if it comes back and they've used the refrigerant that's not supposed to be in there. I mean, I would imagine so, right?

That is correct. That is correct. We will say no warranty if we're able to test the oil and determine if there was a different refrigerant in the oil. Now, you said you've been involved in compression with Copeland. That's one of your main gigs there. And I recently had an opportunity to go to the Copeland Canada head office and we took apart some compressors and looked inside of them.

And it's crazy the amount of things that you can see that contractors could have avoided, like maybe not pulling a proper vacuum. We see like copper plating and stuff inside of them. We see shorted out windings from overheating. Why was it overheating? Was the filter dryer plugged? Was the power bad? There's all kinds of things that can damage a compressor that are field related. And it's kind of along the same lines as contractors putting in the wrong refrigerants.

So field-related compressor failures, I mean, that's a thing, right? It is. On the mechanical side, there's oil return. So we want to keep gas velocities up for starts, stops. Say that ties to liquid refrigerant in the compressor on startup, so we call that flooded starts.

And if we have a problem with the system where the system is providing liquid to the compressor during compressor operation, we call that continuous liquid flood back. So that's two of the pieces that can dilute our oil, cause oil pump out. And something that I've talked about in some of the training classes, the few training classes that I've done, is that mechanical fluid

issues lead to electrical issues. So you pointed out if you could see in that compressor, you might be able to see what's going on. And what will happen is if we get into high compression ratios or out of the compressor envelope operation, you will see mechanical wear. And as these parts start to wear, the cast iron, the ferrous metal might rain down on our winding coils.

And as the compressor stops, starts, the winding coils, they heat up, cool off, they thermal cycle. And some of that conductive material will embed itself and abrade the motor winding varnish and cause the short. So you mentioned that you've seen some shorts in the field, and that may be because you saw mechanical damage with the short.

Yeah, that's one of the other things that I've seen a lot. So I used to work in a building that had this happen quite often where it was a three phase power sort of like distribution to the rooftops and whatnot. But they would have issues with their power where the building would single phase. And this would happen often. And it would take out

motors and compressors and stuff like that to no fault of the compressor or the motor. It was just, so we had to start putting in phase monitors to protect. And ever since we did that, so here's the catch 22 on that.

It's bad for the tech when you put the phase monitor in because now you're not going and replacing compressors and motors all the time and making money. But you're saving the customer money by putting them in, which gives you a better business relationship going forward because you've actually protected their assets. Give me your take on protecting a compressor or a motor.

with a phase monitor so this kind of thing doesn't happen? Oh, yeah. On some of our commercial scroll models, we have what we call Corsons. And so a couple features of that diagnostic and protection module is loss of phase, anti-reverse rotation. So if somebody is on that job site and they rewire that transformer or they replace a contactor, they get two of the three wires mixed up,

the three-phase compressor will reverse rotate. The motor will rotate in reverse. So when scroll compressor is operating in reverse, there is zero mass flow. So the refrigerant's not moving, but the oil may be foaming and falling out of the discharge line or for whatever reason, leaving the compressor.

So without mass flow, we get into a motor overheat situation. So the motor overload will take the compressor offline. And usually the compressor will cycle on and off until somebody, a service person, will go up there and figure it out and get the system back in service. As far as loss of phase, no.

Thank you very much. I think those are great because if you have loss of phase, you're going to just heat up those motor windings and get into a situation that you described replacing compressors. Yeah, I'm glad you brought up CoreSense because I've worked on compressors that have CoreSense.

on them in refrigeration. And it's actually saved some compressors butts in the past because of an electrician going in and messing around with a panel, changing some stuff, swapping a couple of wires, and now the thing's running in reverse rotation. But the core sense has caught it

stop the compressor from running. We go out and that's the alarm on it. We rotate the phases and it runs. We're like, well, somebody must have been downstairs messing with the power, right? Because that's the only explanation at that point. Yeah, and the cautionary note, you also have to look at fans and blowers and all the other goodies. Oh, of course. Yeah. Of course you do. Yeah, of course you do. If you've got a single phase machine, then anything three phases in that machine is going to start to run

in the opposite direction. So good point. Coming back to the compression thing again, we've already talked about this with Josh and I guess there's a misunderstanding still on some of the types of compressors out there like single speed versus two stage versus variable speed. Now we don't have to redo that whole entire conversation we did with Josh, but

You're a new person, a fresh perspective on it. So maybe just quickly give us the benefits of each one, like single stage, two stage, and then variable speed. Okay, sure. Yeah. All scroll motors are two pole. So they operate at all the permanent split and three phase motors, not so much the VPNs, but they operate at 3600 RPM. So for the first two technologies, we have compressors that are when you switch them on, they operate at 3600.

3600 rpm the single stage or what we consider a fixed displacement you switch the compressor on and you get a given capacity for the operation of the compressor the saturated evap saturated condensing so you get a certain capacity and you get that one capacity out of the single stage compressor then moving up to say a mid-tier or something better you

we have what we call two-stage. The two-stage, the motor's going to operate at 3600 RPM, but it gives you the option, there are mechanical devices in the compressor and some ports,

where the compressor can either operate at 65%, 67%, or 100%. So you get two stages of modulation. Again, 65% or 100%. And that's done with 24 volts, a second fuzite on the compressor. And then the third is variable speed, brushless permanent magnet, BPM motor technology.

And those compressors, usually installed, they operate from 20% all the way up to 100%. So they could be load matching. So given the temperature and the sensible and latent load in your house, the BPM or the variable speed technology is going to load match that.

and not overcool or undercool the space. Yeah, that is one of the great things about modulating technology is the ramping capabilities and the load matching because it provides like peak comfort.

You know what I mean? It's just, especially if the system's set up correctly. I mean, if it's all set up right, if your airflow's right, everything's got to be set up correctly in order to get that peak comfort and that longevity out of that system. And I'll go back to electrical protection for inverter-based systems that have modulating compressors. It's very important. And I keep saying this.

That you need some sort of electrical protection on there, like surge, like also voltage monitoring as well to protect that investment or protect that asset, right? It's no different even in residential, right? It's no different.

Yeah, you are paying a premium for that system. And if these protection devices are pennies on the dollar, then it's a good choice to apply them. The compressor and motor drive combinations that we offer, so we can sell the compressor or we can sell the compressor and drive to our customers. So when we sell a compressor and a motor drive together, it is a UL matched piece of equipment. So that's,

The motor drive is listed as the compressor protection. There are no motor overloads inside a variable, a Copeland variable speed compressor. The protection is at the motor drive. So is the fold back and all the other EMI conductive, EMI radiated. So it's also if

variable speed gets you into a whole new realm of an upsell, a premium system that,

but you just want to, to your point, Gary, have the protections in place. You said EMI conductive and EMI radio? Yeah, radiated. Well, there are FCC regulations for variable speed motor drives. So radiated, if you sell a variable speed to a person that is a ham operator or likes their shortwave radio, right?

Without the mitigations in place, there may be some interference that's radiated. On the electrical side, the utility side, if you don't have the proper devices, the chokes, the other devices that will keep the EMI conductive at a minimum, you start sending noise on the utility line. Interesting. I didn't know that.

Cool. So we learned something new right there. I do want to ask you something that I think is fairly important on a modulating compressor. And you guys have a solution for it in your compressor. And I know you do. And I'll ask you to sort of elaborate on it. When you are changing speeds of a compressor, it's running at a low speed because we don't need a heck of a lot. We don't have a heck of a lot of load right now that can hamper our oil return a little bit.

Right. So, and I know in the compressor that you guys offer for modulating, uh,

There's like a positive displacement oil pump inside. Yes. At the, at the bottom of the crankshaft there, we do have in, in our regular, in our fixed speed and two stage compressors, the compressors that operate at 3,600 RPM, there are oil flangers. So it's a little bit of, of oil boost up the crankshaft and,

But for our variable speed, since we want to ensure oil delivery to our bearings and thrust surfaces, we do have an oil pump. Now, when the variable speed compressors are developed at our customers, we are able to supply them with sight glass or sight tube samples. They are able to get a feel for what kind of oil level is in that compressor.

And that allows them to develop their algorithms for oil boost cycles. So our application engineering publications, we recommend oil boost cycles and we might recommend them every once in a while. But that's pretty much a statement where when we...

sell the compressors for development and to our customers, they are going to develop their own algorithms for oil boost. Yeah. And when you say oil boost, I'm going to presume just so the audience understands where you're coming from on that. It's to ramp the compressor up to start bringing oil back. Bring oil back from the evaporator and suction line, especially if there's any

I won't say there was any traps, but just to increase that gas velocity to bring oil back to the compressor. Yeah. Yeah. So the positive displacement pump in the compressor though, when the oil level is a little bit lower than what it normally is, that pump will help to lubricate those bearings in that sort of that low oil period. Right.

Yeah, it'll keep a solid column of oil on our bearings and thrust surfaces. And we rely on the suction gas oil circulation rate, which is pretty low for a scroll compressor. But that also does some misting in the compressor and allows some lubrication of parts. Okay.

Now, since we're on the topic, I want to get your take on, and I've talked about this before with other people, the vapor injection. Okay. To get that extra bit of capacity, especially in heat pump units and those modulating compressors. Yeah, we've developed variable speed compression. We've developed variable speed with vapor injection. And the vapor injection, as you pointed out, it boosts the capacity of the compressor.

So whether the vapor injection is on or off, usually it's on in a certain area of the map for heating. And there are a number of our customers developing what we call cold climate heat pumps. Yeah. Hey, I've had this discussion with many people because they, there's a lot of people online that don't think a heat pump can heat below negative or sorry, 32 degrees Fahrenheit. There's still people saying,

in North America that are in this belief because they haven't kept up to date on the technology that we have available these days, right? Yeah. And it's the technology is coming on the electronic side and on the vapor mechanical side. Okay. Now I want to get your, cause some of the, it's an argument that's had every time something like this is talked about. It's an added cost to get

a machine in your home or your building that is modulating because the compressor is more expensive. It comes with hardware to run it. There's people that just want simple. They just want a capacitor. They just want a contactor and they just want a compressor in their condensing unit. And that's all they want to work on. But

I keep telling them, I said, this stuff is coming. It's not going away. You might as well learn it. You might as well understand it because one time you're going to be up against it and you're not going to know what it is or how to work on it. And you might have to call another company to come in and fix it for you. I said, that's kind of embarrassing. So give me your take on or give me your thoughts on what is needed to start understanding and learning this.

This stuff that is basically the modern or the future of the industry when it comes to modulating systems. Oh, for modulating systems, I think, well, on the compression side, we've got some, you can come at us with our online product information.

You can leverage Copeland Mobile and our new AI Copeland Scout. So that's for the compression piece of it. But if you've got a person that walks up to a system and they open up that terminal box panel and they see a lot of electronics...

please embrace the technology and you'll probably get a lot of information, whether it's system A, B, or C, from their websites and their technical training classes. So we are an OEM that supplies components to another OEM, and then they use our compressors, motor drives in their systems. So there may be something associated on a board that is driving an EXV system

or defrost some sort of algorithm, or how our motor drives are going to interact with the compressor to provide the necessary RPM, or if we're getting into a low charge situation or some abnormal type of operation, how we're going to fold back, keep the compressor online until it can be serviced.

Yeah, it would be for myself. I got to speak for myself. If I walked up to a machine and I dismissed the technology for five years and said, ah, I'm never going to work on that. I'm never going to use that. And I walk up to a machine and the customer is willing to pay me to fix it and I don't have the knowledge or capabilities to do it, I'm going to be embarrassed if I have to pick up the phone and call someone else. So let's get on top of this stuff, guys. It's not rocket science. I mean, if we understand...

a little bit of, of electronics, which if you dig in a little bit, you can read some stuff, watch some stuff, understand a little bit of electronics. And do you have any training courses, Glenn, uh, that coping can bring people up to speed on this stuff as well. So if you guys are looking for a universal, uh,

hot surface igniter ignition module, check out Copeland's White Rogers universal hot surface ignition module. It takes the place of over 325 part numbers out there and has a lot of unique features. Guys, check it out. We do have educational services, but I don't have their schedule in front of me, Gary. I'm sorry. That's fine. We can find it later and put it out there for people. Okay. But yeah, it's

embrace the technology and also apply some good diagnostic skills and don't change parts until she starts. Well, that's the other thing is changing parts until, I mean, you can go to the parts store and pick up 10 different parts and just replace them all and go, I fixed it.

But I mean, do we know why it was broken? Did you, how about we, we find the right part that's not working or failed and replace that one and verify why. There's tech support out there as well. If we need to get ahold of them, there's manuals, there's all kinds of literature out there. I mean, I mean, being a tech now today, as opposed to when I was, when I started in the early 2000s,

We had a two-way radio. We had no internet. Sometimes we had to use a pay phone to call the office. Now we have a mini computer in our back pocket. And like you said, we have all these things that we can use, like Copeland Mobile has got all the information for every compressor under the sun that you guys manufacture. So,

We got to start utilizing this stuff. Yeah. And Gary, not to belabor the topic, but some of these parts are pretty expensive. So the diagnostics piece of it is going to be very important. Listen, you've been in compression for a long time at Copeland. That's been part of your expertise. Is there anything you want to add that...

you think that the audience would benefit from when it comes to compression? And I want to ask you this question that maybe start this off. Is a compressor considered a pump in your, in your mind, or is it considered vapor compression? Because a lot of people say the compressor is the pump. It's the heart of the system. It pumps vapor refrigerant around, but is it actually a pump or is it something else? It's not a pump. Sometimes we get a little bit wrapped around the axle with, with the word pump here at Koflin. Um,

It is a compressor. It compresses vapor. We do not pump liquid. So for example, on a chiller in a pump package, you're pumping fluid. You're not

compressing vapor. So we like to stick with the word compressor. All right, Glenn. So before we head out, let's talk about potential tips or some in-depth information you can give to the audience about the compression cycle in general and how it might help them and benefit them like out in the service calls and whatnot. So on a service call, you may want to consider determining if the compressor is off on the motor overload or

Give it some time to reset if the compressor is warm or if it's hot. And also pay attention to items outside of the compressor, like good airflow, good refrigerant flow. So if you do have a compressor that's not compressing, it's not operating, you may want to give it some time for the motor overload to reset and then allow it to start.

and determine if actually compressing refrigerant. And if it's compressing, then maybe there's something else in the system that you have to look at. So whether the compressor will or will not start, that's one path you can take.

If the compressor is operating, compressing refrigerant or not, that's another path to go down. Yeah. So if it's not compressing refrigerant, but you put your hand on it and it's hot and it feels like it's running, there's something to be said for that because Copeland actually has a compressor. I don't think all of them do it, but that disengage the scrolls when it gets too hot. So you think the compressor is running. If you put your gauges on it, it's like it's

The same pressure on either side, it doesn't look like it's working. And some people actually think they're defective and will change it out. Yeah. And unfortunately, when we receive warranty returns in the Sydney, Ohio, depending on the displacement and how many are sold, parts per million PPM in our database, we see a high number of returns that are what we consider no fault found.

They've come back to Copeland. They've passed ohm high potential, so the stator is good. We put them on bump start. They do compress, and we inspect them. We perform a cut down, and we see very little mechanical wear with a good amount of oil in the compressors. So that's a no-fault found, and unfortunately, we receive quite a few of them. So the tip here is if you encounter what I was just talking about, the compressor's hot,

You put your gauges on. You don't see any movement in each side of the system. Like your suction and your discharge are exactly the same.

chances are the scrolls have disengaged because it's too hot and you got to let that thing cool down. Potentially, I've seen them take 24 hours to cool down just because the amount of heat that's in it. And this is naturally, but if you've got ice or water nearby, like if you're on a roof or there's a water tap there, you can easily get a hose and within maybe 10, 15 minutes with water on it, it's back to normal and you can test it again. But the reason I've seen this happen is

Mostly is because of lack of refrigerant coming back to the compressor. Plugged filter dryer, plugged up TX valve screen because someone didn't nitrogen braze and now there's copper oxide in the system and it's plugging up that screen. Those are the two main causes that I've seen that happen with. Yeah, everything that you described, Gary, manifests into a high compression ratio. It lowers the mass flow back to our compressor and it generates heat. Cool.

Awesome. All right. Well, I mean, Glenn, this was a good conversation. I enjoyed it. We learned some stuff. EMI thing I've never heard of before. So that was interesting. And if anybody's going to take a tip away from this,

Please don't walk away and condemn a compressor just because it's hot and you don't think there's compression happening. Look into it a little bit further before condemning it. You agree, Glenn? Totally agree, Gary. Yeah. Awesome. Cool. Thank you very much, Glenn. Thanks, Gary.