Episode 277. CO2 Experts: Pressure Relief Valves - Sizing, Selecting & Troubleshooting with Jordan Gronkowski

It's really a last line of defense against something catastrophic happening. So if you have a valve on there that's too small for the vessel, then it's not going to, it's not going to stop the pressure from building beyond the, the set limits. But equally, if you have a valve on there that's too large, it's not going to behave properly either. So although people see them as very simple devices that they have to put on the system because the code says so it's, there's, there's a lot more to it So

Welcome to this CO2 experts event. So excited to be here again, 2025 starting off the year. Great. Loving what's going on. 2025 is going to be a great year for the refrigeration industry, CO2 industry. And today I've got a special guest. But first I want to talk about.

Some of the things that we've been doing already at CO2 experts, we've already had experts from all around the world. You do really want to get and rewatch some of these videos, get to the YouTube channel. If you're listening to it on the podcast, go and watch the video. Cause there is lots of great slides getting into selection software.

Some of the things that we've been doing already at CO2 experts, we've already had experts from all around the world. You do really want to get and rewatch some of these videos, get to the YouTube channel. If you're listening to it on the podcast, go and watch the video. Cause there is lots of great slides getting into selection software.

Like today, we're going to dive into and really invest in yourself. That's what it's all about is investing in your knowledge. So you're better tomorrow than you are today. And this is what we do here on a daily basis at refrigeration mentor. And I, if I say anything for 2025 invest in yourself. So welcome to this CO2 expert session today, I have a special guest Jordan and he is uh, pressure relief out expert.

He works for the Henry group. We're going to dive into it a little bit deeper, but we met back at Chilventa and we stopped in and we had, I had a conversation because honestly, I know what pressure reliefs are. I know what they do, but this is, it's something that we don't understand enough. Well, a lot of people that I talk to in my circles, we know that if you have a catastrophic event.

They're to protect the system. So you don't have an explosion or you don't have something blowing up realistically, because these are vessels with refrigerants or some sort of chemical inside them. And ours is refrigerant, but you have these pressure reliefs to stop these catastrophic events. So sizing is key.

They're to protect the system. So you don't have an explosion or you don't have something blowing up realistically, because these are vessels with refrigerants or some sort of chemical inside them. And ours is refrigerant, but you have these pressure reliefs to stop these catastrophic events. So sizing is key.

CO2 transcritical systems, we have multiple pressure points. So on the transcritical side, you can have one pressure relief on the flash tank receiver or the vessel. You could have one size pressure relief on the low side suction. You could have a different size pressure relief all depends on the design of the manufacturer.

And the manufacturers today are doing a fantastic job. They're working with Jordan and his team at Henry and, and coming up with the best solutions for their designs. So if you're working with one of the top CO2 manufacturers, because there are many of them from around the world, they are adding these to their systems.

But us as technicians, designers, and engineers, we really need to understand what should the actual size be? Is it going to be safe? What is the code in our, in our area, what country state or province are in. If you have any questions, please throw it into the chat. Cause we've got a lot going on today.

But us as technicians, designers, and engineers, we really need to understand what should the actual size be? Is it going to be safe? What is the code in our, in our area, what country state or province are in. If you have any questions, please throw it into the chat. Cause we've got a lot going on today.

If you're listening to on the podcast, please leave a review or share this with someone. This is how we grow the knowledge of our industry. That's what we're trying to do here. Uplift the knowledge of the refrigeration industry. Jordan, welcome to CO2 experts. How are you doing? I'm good. Thanks for having me on.

And thanks for the invite. Oh, well, well, I, I knew I wanted to have you on for sure. We, we met in October and like we had some great conversations. So you can go and check out on LinkedIn, a couple of videos on the YouTube channel on a few quick videos we have in there, and we learned about the different trees pressure relief trees or trunks.

I'm not sure exactly the proper terminology, but we'll find that out today on protecting CO2 system, because we know. CO2 systems run at a higher pressure, right? And, and we need to make sure they are safe and I'm excited to dive into it a little bit deeper with you, Jordan, because you're an expert.

How long have you been working with pressure reliefs? Since I left university, probably around, around 18 years or so ago now further back than I care to admit, but yeah, it's been, it's been my focus on my work and life. It's how I started in industry was developing a range of PR, new PRVs and a new methodology, how to design and, and And introduced this new range which was successful.

How long have you been working with pressure reliefs? Since I left university, probably around, around 18 years or so ago now further back than I care to admit, but yeah, it's been, it's been my focus on my work and life. It's how I started in industry was developing a range of PR, new PRVs and a new methodology, how to design and, and And introduced this new range which was successful.

And then after that, it's, it's kind of growing arms and arms and legs from there. And obviously, as you mentioned, CO2 in that time has really taken off as a refrigerant, especially here in the UK and Europe and in America now as well, the North America, it's starting to starting to take off. So, yeah, it's it's an exciting, exciting field.

So I want to ask you a question. What are the biggest thing that you see out? Cause you're an expert at this, right? You've been doing it for 18. You've been designing, you've been sizing, you've been in the manufacturing process, you've been doing it all, but what do you, you feel, or you see that say manufacturers, designers, and even like technicians and contractors are missing on that.

Because like I talk with you, I'm like. I'm kind of ignorant of the pressure relief valve over the years. Like I I'm better now. I understand codes from around the world. I understand the value cause we all it's safety. You know what I mean? It'll relief if the pressures get too high, but what are some of the things that you see that people are missing, kind of missing the boat on in their knowledge of pressure relief versus of having this specific knowledge that.

Because like I talk with you, I'm like. I'm kind of ignorant of the pressure relief valve over the years. Like I I'm better now. I understand codes from around the world. I understand the value cause we all it's safety. You know what I mean? It'll relief if the pressures get too high, but what are some of the things that you see that people are missing, kind of missing the boat on in their knowledge of pressure relief versus of having this specific knowledge that.

Like most of us should have one of the, one of the biggest things, although you know, it is getting better, but one of the things that comes up a lot is somebody looking to fit a valve to a vessel and they have a, for instance, a half inch NPT thread connection, and they just want a half inch NPT valve to fit onto the connection because it's the right thread.

So it must be the right file, but obviously that's, as, as we, we know that's not the, not the case. It's very important that valves are sized correctly because as, as, You covered, it's, it's really a last line of defense against something catastrophic happening. So if you have a valve on there that's too small for the vessel, then it's not going to, it's not going to stop the pressure from building beyond the, the set limits.

But equally, if you have a valve on there that's too large, it's not going to behave properly either. So although people see them as very simple devices that they have to put on the system because the code says so it's, there's, there's a lot more to it as we'll get into today. So, so we might get into it in some of the slides you have, but let's talk about that right there.

But equally, if you have a valve on there that's too large, it's not going to behave properly either. So although people see them as very simple devices that they have to put on the system because the code says so it's, there's, there's a lot more to it as we'll get into today. So, so we might get into it in some of the slides you have, but let's talk about that right there.

Like if you have an oversized valve, so, cause in Canada here, our B52 code States that every five years, I believe they need to be inspected or replaced. Okay. And I think that's around the world. Like it's similar code. So this is, you need to understand the code in the country you're in, but if all of a sudden you need to replace it and you see it there and they put something, a one that's too large on.

And cause you just said it may work erratically. What if someone puts a too large. PRV on a system. Yeah. So we refer to that. The code refers to that as gross oversizing of a, of a valve. And what can happen there, and we'll get into a little bit more on the slides, is that when the valve is too large, effectively, if you can imagine you've got this, I always think it's easier to imagine things if you accentuate.

So you have this huge valve and this tiny vessel. As soon as that valve opens, there's all the gases. shoot out the vessel, almost immediately, because it's such a large valve, and the valve will immediately close again. But then what happens is the gas from the rest of the system creeps out back into the vessel.

So you have this huge valve and this tiny vessel. As soon as that valve opens, there's all the gases. shoot out the vessel, almost immediately, because it's such a large valve, and the valve will immediately close again. But then what happens is the gas from the rest of the system creeps out back into the vessel.

Almost again, immediately, and then that'll open the valve immediately, and then it'll evacuate everything in the space, and then it'll close. And the cycle continues until the valve is what we call chattering, where it, it, it vibrates very quickly, and it's a horrible thing to hear as well. It sounds, sounds terrible.

And if you can imagine, a lot of the valves have things like PTFE or Teflon seats, and this hammering of the seat against the seal, destroys it. It can, in extreme cases, it can actually take the seal out altogether, and then you have a valve that, sure enough, it's closed, but it's leaking. Because you have.

And you've destroyed the seal and did you say that term was chaffing? What was happening? Oh chattering. Okay. Yeah. Yeah. Yeah. Yeah. Yeah. No, and that makes sense. Yeah, i'm excited. Yeah, so let's let's share some slides. So if you're listening to on the podcast make sure that you you key in take some notes get over to the youtube channel watch the video too

Hopefully this will appear on everyone's screen. Yeah, perfect. Good stuff. Right. So we're just going to dive in to this relatively short presentation on CO2 PRVs and safety devices challenges, selection, and a little bit of troubleshooting at the end there as well. Now, Travis, as I said to you, feel free to, sorry, Trevor, feel free to jump in anytime if you have anything you want to highlight or to.

Hopefully this will appear on everyone's screen. Yeah, perfect. Good stuff. Right. So we're just going to dive in to this relatively short presentation on CO2 PRVs and safety devices challenges, selection, and a little bit of troubleshooting at the end there as well. Now, Travis, as I said to you, feel free to, sorry, Trevor, feel free to jump in anytime if you have anything you want to highlight or to.

Well, for sure. I'm sure I'll have lots of questions. So what we're going to cover first off, some specific challenges that CO2 gives us as valve designers. It's interesting to know what, what these are. And then we'll look in a bit more detail at the selection met or how to correctly select the PRB.

Now I'm going to focus on the European standard EN13136. You've got the ASHRAE, I think it's actually 15 in the States. I think it's ASHRAE 15. And again, the two are becoming more and more aligned. I think the ASHRAE standards are becoming more like the EN standards as things get revised. So although this might not be specifically applicable to you guys, wherever you are in the world, It's all the same theory.

So it's, it's, it's good to know. And, and that's the big thing. I want to point that out. I already said it's like depending on where you're at in the world, there's gonna be different codes and regulations and you may, 'cause I, I had a, a friend here, Robert Nash from Copeland send out and I was asking about the press release and he says, per A-S-M-E-B.

So it's, it's, it's good to know. And, and that's the big thing. I want to point that out. I already said it's like depending on where you're at in the world, there's gonna be different codes and regulations and you may, 'cause I, I had a, a friend here, Robert Nash from Copeland send out and I was asking about the press release and he says, per A-S-M-E-B.

31. 5. The system is to be tested at 1. 1 times the design working pressure, but that's going to be different. Maybe here in Canada, maybe in the UK or Ireland or wherever you're at, you know what I mean? So there are Scotland and this is, this is. Important. You could be in Australia, you could be in New Zealand, you could be in South Africa, the codes may be different.

And then in your province, like, like in my province or state, it could be even stricter depending on your local jurisdictions. Okay. So this is very, very important as us, even as a technician, you need to understand, and you might be thinking, why, why does this matter? The designers are supposed to do that.

At the end of the day, as a technician, we're responsible for the system. Not that the engineers are designed we're because we're working on it because it could be two or three years down the road. So just remember that we're if we're the last one to touch is we're responsible for this stuff. So it's important to understand the codes certainly is and so yeah after we talk about the selection We'll have a like a little look at in the Henry online PRV selector that we got, but it takes a lot of the hassle out of the selection process.

At the end of the day, as a technician, we're responsible for the system. Not that the engineers are designed we're because we're working on it because it could be two or three years down the road. So just remember that we're if we're the last one to touch is we're responsible for this stuff. So it's important to understand the codes certainly is and so yeah after we talk about the selection We'll have a like a little look at in the Henry online PRV selector that we got, but it takes a lot of the hassle out of the selection process.

Again, you might have seen Trevor and I covering that at Chilventa last year, one of the videos. Then we'll look a little bit at pressure drop, which is important consideration as well, and pressure drop into the valve, but also coming out from the valve and how that can affect behavior. And then a little bit of proactive troubleshooting, I've called it, at the end of the presentation.

So the first, first thing to look at is CO2 challenges. So obviously, as you guys know, CO2 with the conventional refrigerants on your, on your pH diagram, you tend to be in this kind of region here with CO2, you're up here. So you're beyond the critical point, you're at much higher pressures, much higher temperatures.

So what challenges does that give us as, as valve designers? So. Are CO2 PRVs different? Is the question I've asked here. The answer is not necessarily subcritical CO2 doesn't really behave any massively different from any conventional refrigerant. So although we at Henry have a high pressure range of valves specifically designed for CO2.

So what challenges does that give us as, as valve designers? So. Are CO2 PRVs different? Is the question I've asked here. The answer is not necessarily subcritical CO2 doesn't really behave any massively different from any conventional refrigerant. So although we at Henry have a high pressure range of valves specifically designed for CO2.

All of our valves, even our low pressure ones, are suitable for CO2 because on your transcritical, your subcritical side, low pressure end yeah, normal valves kind of work fine, but transcritical has, has its unique challenges. The obvious one's increased pressure I've put here 130 bar because, again, that's, that's where our limit is on our pressure relief valve range, but I've heard up to 150, 160 bar in some systems which, again, has the, as the impact as a valve designer, you have to look at the rigidity and the structural integrity of the valve at those pressures.

The other thing that comes in consideration there is the CO material as well. You tend to find most high pressure CO2 valves are, teflon or a derivative thereof in the seal material, whereas at lower pressures you can get away with softer seals with better leak tightness, because again, there is not as much force acting on the seal because the valve is not set quite as high.

The other thing that comes in consideration there is the CO material as well. You tend to find most high pressure CO2 valves are, teflon or a derivative thereof in the seal material, whereas at lower pressures you can get away with softer seals with better leak tightness, because again, there is not as much force acting on the seal because the valve is not set quite as high.

Increased temperature obviously goes hand in hand with the pressure as well. Again, that comes back to affecting the seal material. Make sure the seal material is appropriate for the temperature range it's going to be working at. Again, I've put 150, but again, you could even get higher than that. And.

Again, the other consideration from a design point of view with temperature is the spring, because if the valve is in a high temperature environment and you haven't selected the correct spring design or materials or pre stressed it enough, it can actually lose tension due to the temperature over the life of the valve, which makes the valve open early, which obviously is something we don't want.

And the final point I put on here is rapid decompression, which is a term that It's quite well known in the oil and gas industry where the temperatures are much higher. Again, it's effectively, for those of you who don't know, it's effectively in a phenomenon where an elastomer seal, like an o ring or something, the gas, because of the high pressure, can effectively creep into and impregnate that material.

And then when it's exposed to atmospheric pressure or low pressure, the gas bursts out of the material very suddenly and effectively rips it to bits. And so in an oil valve, if you're using a. Again, elastomer seal in the, in the seat itself and the valve opens, you can see there's rapid decompression, which is why, again, choice of material is, is very important for a CO2 valve, especially transcritical.

And then when it's exposed to atmospheric pressure or low pressure, the gas bursts out of the material very suddenly and effectively rips it to bits. And so in an oil valve, if you're using a. Again, elastomer seal in the, in the seat itself and the valve opens, you can see there's rapid decompression, which is why, again, choice of material is, is very important for a CO2 valve, especially transcritical.

So jumping into the selection by calculation method as we've touched on, I'm sure you, you guys all know we've mentioned already that the, the most important thing with the PRV is that it is your last line of defense. It needs to be sized correctly. If it's too small. It won't protect the system. If it's too large, as we discussed earlier, you get chattering and issues.

So there are many standards, again, depending on your local province, country, area. What I'm focusing on here is the M13136, which is a European and British standard which we use constantly here. Again, even though there are many different forms of standards throughout the world, you'll find that if you comply with Something like a recognized standard like 1 3 1 3 6, it tends to be acceptable in most places, or it can be easily modified to the needs of another standard, for example, North America.

So there are many standards, again, depending on your local province, country, area. What I'm focusing on here is the M13136, which is a European and British standard which we use constantly here. Again, even though there are many different forms of standards throughout the world, you'll find that if you comply with Something like a recognized standard like 1 3 1 3 6, it tends to be acceptable in most places, or it can be easily modified to the needs of another standard, for example, North America.

So 6, it looks at three scenarios that you size your valve based on. External heat source, which is effectively a fire, by far the most common one that everyone thinks about when they're Slicing a PRV. Internal heat, which I don't see used a lot. That tends to be the scenario where you would maybe have a heater coil or something inside your system, and you're worrying about that running out of control and adding heat that way, excessive heat that way.

And compressor flow being the other one. So again, Again, typically for transcritical CO2 systems, we sometimes see valves located on the discharge line, and they will be sized to cope with the flow rate of the compressor. So if there's some blockage further down the system, the valve will open and allow the total flow rate of the compressor to be discharged.

And the standard then says that you should consider as many of these as are applicable and you should obviously use the worst case for what path to pick. So there's some calculations involved, which we'll dive into in a sec they require system properties, refrigerant properties, and PRV properties obviously as well.

And the standard then says that you should consider as many of these as are applicable and you should obviously use the worst case for what path to pick. So there's some calculations involved, which we'll dive into in a sec they require system properties, refrigerant properties, and PRV properties obviously as well.

And basically you're looking at two terms, you're calculating a required flow rate, the QMD as it's called, this is what's required to keep the system safe in these scenarios, and you're then calculating QM, which is the actual rated flow rate of the valve. And effectively, you're making sure that one is, you make sure the valve is, has more rated flow than your requirement.

So find the required flow rate is the first step. So as I mentioned, you've got your three scenarios here, external and internal compressor. Looking at external heat source, this is the equation that we use. Again, I'm going to be throwing some numbers and equations up. There's not going to be a test at the end.

Nobody worry. There will be a test. There will be a test. It goes back to something that one of my lecturers said to me at university, was that you don't necessarily have to remember all this stuff, but you have to know that this stuff exists. It's important to know that there is this in the background, and that's why it's important to calculate these things.

So external fire, here's your equation for QnD, and you've got the surface area of the vessel. If it's a simple tank, it's straightforward enough. If we've got something like a, like a condenser, You use the boxed area if you like, rather than taking all the surface area, the fins, that, that it, it doesn't work if you do that.

So external fire, here's your equation for QnD, and you've got the surface area of the vessel. If it's a simple tank, it's straightforward enough. If we've got something like a, like a condenser, You use the boxed area if you like, rather than taking all the surface area, the fins, that, that it, it doesn't work if you do that.

H wrap is the heat of vaporization, which is taken at 1.1 times the set pressure. And then you've got the larter, which is the density of heat flow rate. Again, that is given in the standard as 10, but it may vary if you've got things like inchi shape or things on the, on the vessel, internal heat source.

Very similar equation, but you have the same heat of evaporate, heat of vaporization, but you also have this rate of heat production term, which again comes from the heating element or whatever you're using in that scenario. In compressor flow, really what this equation is doing is working out the the flow rate of the compressor in kilograms per hour, you're looking at the volumetric flow, which are kind of these terms taken together multiplied by the rho, which is the vapor density, and nu to the base V, which is the volumetric efficiency of the compressor.

So question on these different calculations, we're all, you're trying to figure out the kilograms per hour or pounds per hour SCFM, depending on all of them, how do they like, how different are they? Will, when you do these calculations, we're not going to get into the calculations too much. And I know your software does all this stuff, but how do they differ?

So question on these different calculations, we're all, you're trying to figure out the kilograms per hour or pounds per hour SCFM, depending on all of them, how do they like, how different are they? Will, when you do these calculations, we're not going to get into the calculations too much. And I know your software does all this stuff, but how do they differ?

Like, because maybe they will. Change faster like a I guess a fire versus someone shuts his dish something on the discharge line. Yeah Is that what it really is? It depends on the system. So if you might have a system where your receiver, so your external heat source, you're using your receiver as the calculation, is maybe, I don't know, average size, but you maybe have three or four compressors feeding the system.

So in that case, you would find that your compressor flow would be the one That will drive the selection of the PRV, because it will be much larger. Ah, I get you. Conversely, you might have a small one compressor system, but you might have a huge receiver. In which case, this will come out as the worst case, and that's what you use for the Ah, now, now I get it.

So in that case, you would find that your compressor flow would be the one That will drive the selection of the PRV, because it will be much larger. Ah, I get you. Conversely, you might have a small one compressor system, but you might have a huge receiver. In which case, this will come out as the worst case, and that's what you use for the Ah, now, now I get it.

Now, now I definitely get it, because depending on the design of the system, will depend on the equation you have to use, like the components in the system. Correct, correct. The standard does say you, you always use all of them, or as many as are applicable, and then pick the worst one. But you can usually Most of the time it's the external heat source that people use.

Again, as I said, except from what we typically see in transcritical CO2 systems are people using PRVs on discharge lines, and then it's obviously the compressor because it's not even connected to the receiver. It's coming straight from the compressor. That's right. Yeah, yeah. Well, I learned something there.

So, you've got your, your QMD, if you like, your required discharge. Next, you find the right PRV. So, here's another equation. Again, lots of terms in here, but this is the equation that tells you what the rated flow of the valve is. And again, as I said earlier, QM, which is the valve flow, must be greater or equal to.

QMD, which is your requirement. So just go through the terms here. C is the function of the isentropic exponent for the refrigerant, which you get in the standard for many, and it can be derived from the isentropic exponent itself. Again, if you can't find it in the standards or anywhere, the refrigerant manufacturer can usually get that to you.

QMD, which is your requirement. So just go through the terms here. C is the function of the isentropic exponent for the refrigerant, which you get in the standard for many, and it can be derived from the isentropic exponent itself. Again, if you can't find it in the standards or anywhere, the refrigerant manufacturer can usually get that to you.

A is the flow area of the PRV, which again, the manufacturer will have. This KDR term is specific to the European standards and it comes from the certification of the valve when it's flow certified. Although it's specific to European standards, we at Hendry, our valves are dual certified to both European standards and the A SME standards in America.

And we therefore flow test our valves. At the National Board in America, and we get a rated slope which is again, one of the terms that we use from the American side but we can derive KDR from that. And so even if you have an American valve, it's totally just set to certified on slope, you can again derive this KDR term from the slope.

Kb is what's called the theoretical capacity correction factor for subcritical flow, which is a bit of a mouthful, but effectively that is always one if your valve has a supersonic internal flow, which all of these refrigerant parts generally are. So you don't need to worry about that term too much unless you have a strange valve.

Kb is what's called the theoretical capacity correction factor for subcritical flow, which is a bit of a mouthful, but effectively that is always one if your valve has a supersonic internal flow, which all of these refrigerant parts generally are. So you don't need to worry about that term too much unless you have a strange valve.

P0 or P naught is the actual leaving pressure, which is 1. 1 times your set pressure plus atmospheric pressure. And the final term there is your not, which is a specific volume of refrigerant in meters cubed per kilogram. And in the terms of the units here, but again, you can get other units. Yeah. So there's a lot there, you know, this is engineering stuff.

This is design stuff. This is stuff that we, that Jordan knows inside now. And this is the behind the scenes where a lot of you here that are engineers and designer understand this stuff, but as you know, for. Technician to size and all this is done. You don't have to worry about this. This is done in the software, the selection softwares is all inputted in there.

But it's very important that like Jordan said earlier is to understand that this is what's happening in the background. Correct. Because when I look at that, Jordan, I'm like, Oh man, that's above me. That's for sure. And that's, and that's kind of the point of this a little bit as well, is to show how easy it is using our selection tool that you don't have to anymore, worry about in the olden days, you would have had to get a pen and paper and go through this.

But it's very important that like Jordan said earlier is to understand that this is what's happening in the background. Correct. Because when I look at that, Jordan, I'm like, Oh man, that's above me. That's for sure. And that's, and that's kind of the point of this a little bit as well, is to show how easy it is using our selection tool that you don't have to anymore, worry about in the olden days, you would have had to get a pen and paper and go through this.

Which I've done many times. Well, I see quite a few people on the call right now who have definitely done it as well. Yeah. Good stuff. Good stuff. Okay. So that was the selection process basically. So just to summarize establish your Q and D and select the right PRV to meet or exceed that in your QM.

And this is what I've mentioned about gross oversizing that we touched on earlier. There is no definition given in the standard about what gross oversizing is. It just says not to do it or to avoid it. We, based on some research we've done and some independent research have found we tend to typically classify gross oversizing as five times.

So if the valve is, has five times the flow of the required flow, then we would call that gross oversize. And that's where this chatter and seal damage we talked about earlier can come in. A couple of other sections of the standard just to make us aware that it's there. Variations in the phi term, which was the density of heat flow rate.

So if the valve is, has five times the flow of the required flow, then we would call that gross oversize. And that's where this chatter and seal damage we talked about earlier can come in. A couple of other sections of the standard just to make us aware that it's there. Variations in the phi term, which was the density of heat flow rate. Again, if you've got insulated vessels and things, that term can, can vary a little bit from the 10 that is stated as recommended in the standard. Liquid expansion is a little bit of a different beast. Compared to gas, because obviously gas is compressible, liquid isn't. So it behaves slightly differently.

You do need to make sure if you're fitting a valve in a liquid line, that you use a valve that is rated for liquid discharge. Henry valves are all rated for gas discharge only, so it shouldn't be used in the liquid line. You do get special valves that are rated for liquid. Again, subcritical flow that I spoke about earlier, most valves tend to be critical flow through the valve itself.

So that, that term doesn't mean, but if you have a different valve, then the manufacturer would probably advise that you use a different term. And a little bit, we'll talk in more detail later about the adjusted PRV discharge capacity QMD and the pressure drop calculations, which are a whole other branch of calculations and things that I won't get into in too much detail here.

So before we move on, so these are Different standards within the code for, okay. So let's just talk a little, just quickly, cause we know CO2 system need to be insulated very well because they're there, they run colder, a lot of moisture and it can cause rust and deterioration and stuff. So we did, there's a lot of insulation on there.

So before we move on, so these are Different standards within the code for, okay. So let's just talk a little, just quickly, cause we know CO2 system need to be insulated very well because they're there, they run colder, a lot of moisture and it can cause rust and deterioration and stuff. So we did, there's a lot of insulation on there.

So when we talk about various in installation, do you mean actual in, like you said, they're insulating of the. That flash tank receiver or that vessel that will change the selection for the PRV. It may do it may do. So remember if we skip back a slide and what we're doing for the external heat source method here is we are looking at the surface area of the vessel and various other terms.

The reason we're looking at the surface area of the vessel is what this calculation is trying to figure out is. If there is a fire in the plant, how quickly is the heat going to be absorbed into the vessel? So that's why he's worried about surface area, rather than, a lot of people think it's the volume of the receiver that matters, but no, it's the surface area, because it's how quickly the heat's going to be absorbed in, because that'll determine how quickly the pressure and temperature is going to rise inside the vessel, therefore how quickly the, how much capacity the valve needs to have to vent that safely and stop it getting above.

The reason we're looking at the surface area of the vessel is what this calculation is trying to figure out is. If there is a fire in the plant, how quickly is the heat going to be absorbed into the vessel? So that's why he's worried about surface area, rather than, a lot of people think it's the volume of the receiver that matters, but no, it's the surface area, because it's how quickly the heat's going to be absorbed in, because that'll determine how quickly the pressure and temperature is going to rise inside the vessel, therefore how quickly the, how much capacity the valve needs to have to vent that safely and stop it getting above.

a certain temperature over limit. So if you have insulation, then that's going to affect how quickly the fire heat will be absorbed into the vessel. Yeah. And so just to put that in terms, I guess you have a, I say a lighter and you put a lighter on the bottom versus you have a blow torch. You know what I mean?

So it's what you don't do, but that you just get more heat on it quicker. And so now with that variation, so we're talking about the first requirement, but with the insulation on it, cause a lot of times it's one inch, one and a half inch, even up to two inch insulation on some of these vessels that will change the sizing and selection of the PRV.

It could do, it changes that, that term at the top the Oh, okay. The Greek, my Greek letter's correct, that's 5. So this is given in the standard as a value of 10 as standard, but it does say you should account for insulation. It'll go up or down depending on type of insulation, level of insulation, etc.

It could do, it changes that, that term at the top the Oh, okay. The Greek, my Greek letter's correct, that's 5. So this is given in the standard as a value of 10 as standard, but it does say you should account for insulation. It'll go up or down depending on type of insulation, level of insulation, etc. And because it's multi the top line's multiplied by that, it's going to have quite a big effect. So yeah, it could, it could well change the selection. Yeah, that's cool. Yeah, it's something I would not have thought of. so the liquid Let's get into the liquid inspection So this is important. We we Need to make sure that if it's gas prv it needs if it's on the gas lines discharge line suction line It's gas, but if it's in the liquid line, you need a different design. And what, why is that?

Is it just because you need more flow? Cause like liquids denser or whatever, like that is, does it need to be bigger? Like, can you just give us just a little insight on the difference between a liquid and a vapor one again, you might. Yeah. So from, from, I mean, again, we, we don't make any liquid valves at Henry.

So it's something that I've dabbled in, but I wouldn't say I'm an expert. But fundamentally, liquid and gas behaves differently, especially flowing through a valve, where if you look at the fluid flow and the aerodynamic or fluid mechanics, I should say, inside the valve, you're getting really high accelerations of flow in very, very short spaces, changes in temperature, changes in pressure.

So it's something that I've dabbled in, but I wouldn't say I'm an expert. But fundamentally, liquid and gas behaves differently, especially flowing through a valve, where if you look at the fluid flow and the aerodynamic or fluid mechanics, I should say, inside the valve, you're getting really high accelerations of flow in very, very short spaces, changes in temperature, changes in pressure.

You can get what's called cavitation in liquid. Where so yeah, it basically, yeah, it doesn't, doesn't behave like a gas, but that goes into too much detail. Yeah, and with CO2, you get dry ice. So that's what it means. All of a sudden it blows out liquid and then it just stops. You know what I mean?

That's, that's an issue. So, okay. I totally understand that. Okay. I don't think I've seen, honestly, on a CO2 system. I'll have to dive in a little bit quicker if I ever seen any on the liquid line. I don't think so. Like they will usually point back into like a vessel or something and the vessel would be gas.

So yeah, I'll have to look into that. Yeah. It's, it's maybe more for conventional refrigerants. Did you say so? Yeah, so, okay. Move on. Do you have anything else on that page you want to pick up on or okay? No, no, let's keep going. Let's go. So, some complexities specifically for CO2. So, eagle eyed amongst you will have noticed that HVAP and nu naught are calculated at saturated conditions at p naught, but obviously with transcritical CO2 we're not at saturated conditions, we're above the critical point.

So yeah, I'll have to look into that. Yeah. It's, it's maybe more for conventional refrigerants. Did you say so? Yeah, so, okay. Move on. Do you have anything else on that page you want to pick up on or okay? No, no, let's keep going. Let's go. So, some complexities specifically for CO2. So, eagle eyed amongst you will have noticed that HVAP and nu naught are calculated at saturated conditions at p naught, but obviously with transcritical CO2 we're not at saturated conditions, we're above the critical point.

So, what if, in this case, p naught is above the critical point, which is your supercritical CO2? So this is what the standard says but to paraphrase effectively, if that is the case and you're above the critical point, HVAP and V0 shall be taken at the critical temperature minus 5k. So when you look at your refrigerant properties, you go down 5k from your critical temperature, and that's where you take these values from, regardless of how high the pressure is.

Well if the temperature is above the saturated temperature, so you've got a superheated gas, then again the standard gives you this, which effectively says that if you have a superheated gas, then each FAP shall be taken at saturated conditions. So again, even though you're to the right of this case of your saturated line, you take the values from the saturated line.

You mentioned that they are, Trevor, at risk of solid CO2 formation in the in the, the discharge of the PRV line. Again, that's something that's mentioned in the standard, but again, they, they don't give much advice as to how to, how to avoid it, except for saying it should be avoided, which is helpful.

You mentioned that they are, Trevor, at risk of solid CO2 formation in the in the, the discharge of the PRV line. Again, that's something that's mentioned in the standard, but again, they, they don't give much advice as to how to, how to avoid it, except for saying it should be avoided, which is helpful. Again, they, Advice that we typically give are that ideally outlet pipe work should be avoided altogether and the valve should just be allowed to vent. There are cases where that's not possible because maybe the valve's at, for example, head height somewhere or somebody might be working and you don't want that to discharge off straight into obviously somebody's face.

Could be, could be very dangerous. So if you do need to use some outlet piping to to change the angle of the outlet or flow, generally try and use the shortest length and the largest diameter pipe possible. So again, for an angled valve coming out, if all you want to do is point it up the way, then a simple angle that would point the flow up will would be better than having to pipe it all the way through meters and meters of pipe artillery, because that's where you'll get the solid CO2 forming, which is a blockage in the exit of the valve, again.

Potentially bad adventures. So yeah, let's stick on that point because I know here in canada This is why you need to know your code different provinces in here have different rules and regulations so some province say that every prv depending on the system and depending on if it what type of room it's in They need to be vented outside.

Potentially bad adventures. So yeah, let's stick on that point because I know here in canada This is why you need to know your code different provinces in here have different rules and regulations so some province say that every prv depending on the system and depending on if it what type of room it's in They need to be vented outside.

So now we know CO2 compressors have discharged pressure reliefs on them. So some provinces may say, and depending on who you talk with as the agent, who is doing the inspection may say, you need a pipe them all the way outside. And some other ones say you don't need them because you have mechanical vent by code here in Canada.

This is something that still is a gray area. That is not pointed out in the code. And I I'm sure this is other parts of the world as well. It's kind of gray and depending on the inspector you get, they may approve or disapprove the installation of those PRVs. We know one thing we cannot have a shutoff valve before any pressure relief.

And I know we didn't get into it yet. You cannot do that because if someone forgets it, shut off or something like that, their accident could happen. And then now you've got a ticking time bomb potentially. You can't have it at at the outlet, just like Jordan just said, you can't put it at the outlets.

It's the same thing. If you shot it, even though the pressure relief goes off. It's blocked. It can't go anywhere. And so this one here is I talk with designers, I talk with engineers and I talk with contractors and it's a gray area, depending on where you're at. The best thing possible is to, like Jordan said, not have anything on the outlet and be outside.

It's the same thing. If you shot it, even though the pressure relief goes off. It's blocked. It can't go anywhere. And so this one here is I talk with designers, I talk with engineers and I talk with contractors and it's a gray area, depending on where you're at. The best thing possible is to, like Jordan said, not have anything on the outlet and be outside.

But that's not the case. There's so many pressure reliefs on systems now. I've seen one that I was at, they had seven compressors on the medium, four or five on the low temp, and all of them were headed together into a big large header to go outside. You know what I mean? And then have one big one go outside.

So. Please just follow up with this, find different people in your province, state, or country and ask them questions because they honestly, some of them don't know, because I've been reaching out to the people that are supposed to know the code and it's great for them. So follow up, follow up, follow up, because I did have contractors reach out to me here saying they had to pull out all their installations or they had to go and re pipe, pipe the reliefs all outside.

So. Please just follow up with this, find different people in your province, state, or country and ask them questions because they honestly, some of them don't know, because I've been reaching out to the people that are supposed to know the code and it's great for them. So follow up, follow up, follow up, because I did have contractors reach out to me here saying they had to pull out all their installations or they had to go and re pipe, pipe the reliefs all outside. Yeah. So it's a touchy area, even with you, you know, you deal with this cause they're calling you up. Well, what's the goal? Well, I don't know. Cause that area of jurisdiction could be different. Some could say something just like we said, some could say, okay, you can put something at the outlet as long as it's a bigger diameter, just like Jordan said.

Some others say, no, you have to pipe the pressure relief and put the pressure relief outside. So this is where you need to work with your local authority. Definitely. So I've got time to run through a selection on the online or do you want me to? Yeah, let's do it. I think this is important because let's show, show how anyone can really do this. If, if you're in a tech, if you're a tech, you're doing an install and you're a technician, you want to understand this. This is very, very important.

Or if you're a designer. Yeah, so across here to the Henry Tech website. This is our technical United Kingdom page. If you're on the Henry Tech website and you want to get to it, you simply go to technical, click on United Kingdom, and you bring up this. We've got lots of useful stuff on here as far as operating instructions, and declarations of conformity, various technical brochures and things.

Or if you're a designer. Yeah, so across here to the Henry Tech website. This is our technical United Kingdom page. If you're on the Henry Tech website and you want to get to it, you simply go to technical, click on United Kingdom, and you bring up this. We've got lots of useful stuff on here as far as operating instructions, and declarations of conformity, various technical brochures and things.

The bit we're interested in just now is the PRV selector here. So I'll just bring this up. And I'll log in quickly. Again, to set this up, you just click the sign up button and you'll get a quick email just confirming your email address which you click a link on and then you, it's a one time thing, it's free, and then you can log in at any time you like.

So first page, so the way it works, you've got four different sections. And we just work through them step by step. Yeah, first off select your refrigerant, so we're going for R744 for CO2. Again, set pressure, again, let's go 120 bar. You can enter this in PSI, you can kill the Pascals any of the three units, it doesn't matter.

Next, this is our three discharge methods. So this is what we talked about. So we've got internal. There's your QH term asking you for that. You can click external as well. And again, this is your cylindrical. Is it a box? Do you know the surface area? So you can just override it by putting area. And again, you can use meters or inches.

Doesn't matter. Here's your density or heat flow rate term we talked about. Normally, this is what the standard set is normally assumed, but a higher value can be used if necessary. Again, depending if you've. Okay. Let's just talk about that for a second. So just say I have a one inch insulation on the vessel.

Doesn't matter. Here's your density or heat flow rate term we talked about. Normally, this is what the standard set is normally assumed, but a higher value can be used if necessary. Again, depending if you've. Okay. Let's just talk about that for a second. So just say I have a one inch insulation on the vessel.

How, what would number would I put in there? And like, how do you, is that another calculation? There's another whole calculation for that. Good question. The standard doesn't, doesn't tell you. So I don't know Okay. That that's fair. So if anybody knows can, and it's someone, it's someone that, yeah, it's another, as you say, and there's lots of this you'll find in the standard, there's great areas where it says you need to do this.

And then somebody ask the question, well, what do I do? Well, don't ask me. I'm just the standard. I don't know. So yeah, it's to do it again, it's, it's looking at the, the heat density of heat flow rate. So you would have to. Get a feel for how your specific insulation and the thickness of the insulation affects the heat flow rate into the, into the vessel, which is, again, it's, it's, there's no guidance really how to do that in the standard, there may be other standards.

So this, I guess this is where someone would have to go to the insulation company who designs the insulation and find out what that fire rating is for that insulation, I'm guessing. I'm just throwing things out there. If anybody knows this, please throw it in a chat, reach out to me. I would love to find this out as well.

So this, I guess this is where someone would have to go to the insulation company who designs the insulation and find out what that fire rating is for that insulation, I'm guessing. I'm just throwing things out there. If anybody knows this, please throw it in a chat, reach out to me. I would love to find this out as well.

So we can share this knowledge with other people because these, this, I'm really trying to get a lot of these gray areas for people to have a better understanding. We know we'll never get all the gray areas out of standards and stuff. But if anybody has that information, please. send me an email info at refrigeration mentor.

com. And I'll try to get this out to the public. So I would like to the refrigeration industry. Yeah. Yeah, definitely. So yeah, external, I mean, you've got your compressor method, you talked about as well where you can put in all your terms or again, if you know the. volumetric flow rate, you can enter it directly.

So again, as the standard says, you should consider as many of these as possible. So you can tick all three boxes and use all three and the software will automatically then select the worst case scenario and select the valve based on that. For the purposes of today, I'll just. I'll just use the external method and we'll just override it with a simple value of 10 meter squared.

So again, as the standard says, you should consider as many of these as possible. So you can tick all three boxes and use all three and the software will automatically then select the worst case scenario and select the valve based on that. For the purposes of today, I'll just. I'll just use the external method and we'll just override it with a simple value of 10 meter squared.

Next step again we'll cover this right at the end of the presentation a little bit whether you want any additional components, so I'll tick the boxes just for the sake of an example, 3D vowels and rupture discs, and then we can click calculate, and that takes us to the last page. What I've got here are all the valves in the Henry range that are suitable.

Again, you can see here 5701EX and the 5702 inlet connection, outlet connection. This is your QM we talked about in the, in the calculation. This is the actual rated flow rate of the valve of CO2 at the, at the set pressure. Again, three way valves and rupture discs that fit. If you expand the box here at the top, you get all the calculation parameters.

So this is all the formulas we talked through. Here's a reference to the standard and here's all the parameters that, that, that has come out from, for this calculation, the surface area that we entered and here is your QMD. This is your required discharge capacity in kilograms per hour. So this is the requirement and you can see here 3 we're getting a valve with 3 5 30 and then 9.

So this is all the formulas we talked through. Here's a reference to the standard and here's all the parameters that, that, that has come out from, for this calculation, the surface area that we entered and here is your QMD. This is your required discharge capacity in kilograms per hour. So this is the requirement and you can see here 3 we're getting a valve with 3 5 30 and then 9.

This, the software will not select a valve that is grossly oversized, so you can be confident that even though this is a larger valve, see, see, usually you would pick the closest one because it's the most efficient. To pick the smallest one, the one that's closest to your, your requirement. But maybe you've got an inch connection on your vessel and you don't want to have an additional leak path by having an additional connection.

So you could quite happily go with a 5702B in this case. So, so for an example there, it says external is 3. 225 as a minimum requirement. If your actual requirement is 3. 3, that would be good. Or even 3. 225 would be good. Yeah, so it has to be equal to or exceed. Okay. Yeah. As long as there's safety factors in all these categories.

So you can always think, well, it should always be bigger, but if it equals to it, then it's acceptable. And just to point out that that's a comma rather than a point. So it would be 3, 225. Yeah. It would be difficult to see on the screen. Yeah. Sorry. 3, 000. 225. Okay. Yeah. Makes sense. Okay. So last point is just to, as it says here, collect, connect which one you want.

So you can always think, well, it should always be bigger, but if it equals to it, then it's acceptable. And just to point out that that's a comma rather than a point. So it would be 3, 225. Yeah. It would be difficult to see on the screen. Yeah. Sorry. 3, 000. 225. Okay. Yeah. Makes sense. Okay. So last point is just to, as it says here, collect, connect which one you want.

So let's go for the 5701EX. Once we click that box, we get more data at the bottom here. Again, here's your formulas that we talked about. Here's all the different parameters and the valve that's come out. Again, we've got the option here to select which three way valve we want. I'll just pick that up in a moment, and I'll give you some more parameters of the three way valve, which is important when you look at pressure drop, which I'll do in a second.

You can go back by just by clicking and deciding you want to change something. So say you want to, you've got, oh, I made a mistake there, it's supposed to be five. You can recalculate, you can jump straight to the end again. Now you can see because we've reduced the surface area. Our requirement is now 1, 612 because it's half the service area.

So we've got two different valves. We've got the valve we selected last time, but we've also got the option of the smaller one now, which is 1898. Again, gives you the option to tick all that. Once you've completed this and you've got your selection fine, you could send an email to Henry. But more importantly, you could download, or more usefully, I should say, you could download this as a PDF.

So there's The most your PC, and this is laid out exactly as the standard and requires with all the references, all the equations and all the information there. So this is really useful because when you put your design of your system together and you you've been notified, body asks for the proof that you've selected your PRV collected.

So there's The most your PC, and this is laid out exactly as the standard and requires with all the references, all the equations and all the information there. So this is really useful because when you put your design of your system together and you you've been notified, body asks for the proof that you've selected your PRV collected.

you present this bit of paper in your technical file and job done. So it really is a one stop shop for, for everything. Yeah. And so yeah, that, so that's, that's that. Again, easy enough to get to. I'm sure Trevor will share the link around for it for anyone who wants to have a play about with your own selections. And we'll get back to our presentation.

So, as I said, advantages of Selector, as you guys have seen there, it's pretty user friendly it's pretty customisable, you can play about with different figures and values, you can look at different scenarios at the same time, it's in full compliance with the standard, and again, you get that downloadable sheet for your design file at the end.

So how are we doing for time? We we're getting, we're good. Oh, we're good? We're good. Okay. Okay. So I won. I won't, important stuff. We're good. I won't spend too much, but I'll, I'll try and zip through, but I can't talk too fast sometimes. So slow me down if I need, if you need to. No, I think there's pressure drop calculations.

So how are we doing for time? We we're getting, we're good. Oh, we're good? We're good. Okay. Okay. So I won. I won't, important stuff. We're good. I won't spend too much, but I'll, I'll try and zip through, but I can't talk too fast sometimes. So slow me down if I need, if you need to. No, I think there's pressure drop calculations.

So pressure drops in pvs. Why, why is it important? You talk about pressure dropping in the inlet line pressure drop in the outlet line. What, why is that important? So this is a, a typical straight through PRV with an angle outlet on the top. This is when the valve is closed. This is the normal condition that the valves here at the time, red.

Coloring pressure here, so red is high pressure. When the valve opens, this is a simplistic rendering of what actually happens. So the, as the flow accelerates through various portions of the valve and geometry, is that it'll effectively, the pressure drops. So we start off with red through orange into the blues and out the tops.

And this is how the valve is designed to behave. What's the effect of excessive pressure dropping a PRV? So first of all, if you've got pressure drop in the inlet or the outlet, there's no difference in set pressure. If you've got a, a long pipe that puts too much pressure, excessive pressure onto the valve due to, you know, when it's flowing, it doesn't change the set pressure or the valve at all.

So the valve is still open at the correct pressure, but what will happen is that the valve's forced to close unnaturally early, and it is not operating as designed. So in extreme cases, it's very similar to what we talked about with the chatter with the oversizing, it can result in seal damage and loss of seal integrity.

So the valve is still open at the correct pressure, but what will happen is that the valve's forced to close unnaturally early, and it is not operating as designed. So in extreme cases, it's very similar to what we talked about with the chatter with the oversizing, it can result in seal damage and loss of seal integrity.

So to try and visualize that a little bit for upstream line and components, so you've got things like three way valve structures, et cetera and just pipe, long pipe in the inlet line. If you have a pressure drop in that line because your pipe is too small diameter or it's too long, you've got excessive pressure drop.

This is effectively what the valve sees. So where it saw when it initially opens again, everything's static, nothing's flowing. It'll open with that high pressure and. It'll vent. But then as soon as it opens and the flow starts, that's where this buildup pressure drop starts. And the valve sees a lower pressure.

So you notice this has changed from yellow, from red to yellow. It's seen a lower pressure. Because this happens instantaneously, pretty much, the valve then wants to close again. And as soon as it closes, the flow stops and the pressure builds up again because you, all your built up back pressure is, is away.

And then the valve opens and again, the cycle repeats. Very similar to what I explained before. And you get this chatter, the piston moves up and down and chatters. So what can cause that? Things like rupture disks that are incorrectly sized, three way dual structural files that are incorrectly sized, and obviously piping that's, that's too large or too, too long or too small diameter.

And then the valve opens and again, the cycle repeats. Very similar to what I explained before. And you get this chatter, the piston moves up and down and chatters. So what can cause that? Things like rupture disks that are incorrectly sized, three way dual structural files that are incorrectly sized, and obviously piping that's, that's too large or too, too long or too small diameter.

And again, similar to the effect of gross labor per size of the PRV. So, so basically we're saying that if, if you have just a rupture disc or the three way valve is too small, like it's size incorrectly, that the pressure will build up, it'll open up, but then it'll close too quickly. Yeah. It'll close because it's effectively, the pressure it sees disappears.

As soon as the flow starts, it's restriction of flow, it sees less pressure. So it closes. But then the flow stops. So the pressure increases again. Yeah. Because what we want to do with the pressure relief, we want to let out enough so that when it seats again, it's at a safe, like a safe pressure in the vessel or whatever you relieve from to, to hopefully not relieve again.

Is that correct? Correct. Yeah. The valve needs to open and discharge. I would call it discharge natural, naturally a nice. smooth piss of, of noise as it's designed. If you, if you restrict it in either of these ways, then it's, you're forcing it to close, but it's not ready to close yet. So it wants to open again.

Is that correct? Correct. Yeah. The valve needs to open and discharge. I would call it discharge natural, naturally a nice. smooth piss of, of noise as it's designed. If you, if you restrict it in either of these ways, then it's, you're forcing it to close, but it's not ready to close yet. So it wants to open again.

And this, this is where you get the chatter. So downstream line is the opposite. So you've still got your, your high pressure at the inlet, but if you have a long, long, excessively long, excessively Narrow diameter pipe on here, the pressure doesn't drop enough through the PRV because you have all this built up back pressure behind it, and it's the same thing.

In fact, from this point of view, it's getting forced closed by the excessive pressure in the outlet as soon as it closes. That flow stops. So as soon as the flow through here stops, your back pressure disappears because there's no, there's no flow and the pressure is back to atmospheric pressure. So the valve will open again, but as soon as it opens, the flow starts and you're into the same scenario.

So it's the same. It's the same thing, but on the downstream side, that's usually caused by excessive. Piping either length or short diameter and can also be called not so much for CO2, but some refrigerants and things like ammonia where we discharge into a vessel rather than discharging the atmosphere and that can obviously have back pressure effect as well.

So it's the same. It's the same thing, but on the downstream side, that's usually caused by excessive. Piping either length or short diameter and can also be called not so much for CO2, but some refrigerants and things like ammonia where we discharge into a vessel rather than discharging the atmosphere and that can obviously have back pressure effect as well.

You get superimposed back pressure as well. And that's an important point is that All Henry valves are back pressure dependent, so they are designed and they must relieve two atmospheric pressure. You get some PRVs that are specifically designed to be back pressure independent. Now they can deal with a certain level of superimposed back pressure, they call it.

So they're charging into a pressurized environment as opposed to charging the atmosphere. So it's important to make sure you get the right valve from the job. Yeah. And where do you see that more in industrial? Is that where you would see it in like ammonia? Things where the refrigerants specifically nasty or harmful.

You don't want it in the environment. You would discharge to a receiver or something, yeah. Yeah, exactly. So how do we deal with all this and how do we get our heads around how do we know if the pipe's too big, too small, you know, all the rest of it. Back to the same standard again for us in Europe. I'm sure, I'm not sure what the equivalent ASME Standards are 8, ASHRAE standards are, but I'm sure that there will be some there.

If anybody knows, stick it in the comments. But yeah, 1, again, there are calculations in there. And limits so the limits from 6 are 3 percent of set pressure on the inlet side and 10 percent of set pressure on the outlet side. If you have a back pressure independent valve, I think that's 20 percent on the outlet side you can get away with.

If anybody knows, stick it in the comments. But yeah, 1, again, there are calculations in there. And limits so the limits from 6 are 3 percent of set pressure on the inlet side and 10 percent of set pressure on the outlet side. If you have a back pressure independent valve, I think that's 20 percent on the outlet side you can get away with.

Again, for this, if any of you is doing this and they want a little bit of help work with the calculations for this, I'm not going to put the formulas up because they're even worse than the ones before. There is support available from Henry. We don't have it online as yet. But we have an in house tool based on Excel, which again, will work through the various calculations.

You can add in different amounts of header lines and things that can work out what diameter of pipe. You should be, or is the minimum diameter you could use for that. And again, we can send you that as a PDF. So if anyone needs any help, then please, please give our tech team a call.

So the last section, I just want to run through quickly is the what I've called proactive troubleshooting for PRVs, so. Mostly it's, it's the safety device kits that you see on screen here. Again, if you saw Trevor and myself at Chilventa, we covered a little bit of this on the stand. So PRVs in general are fail safe devices.

So the last section, I just want to run through quickly is the what I've called proactive troubleshooting for PRVs, so. Mostly it's, it's the safety device kits that you see on screen here. Again, if you saw Trevor and myself at Chilventa, we covered a little bit of this on the stand. So PRVs in general are fail safe devices.

So they are designed so that if any individual part of the valve breaks, they're going to open and vent. So there's no really, from a, from a system pressure point of view, there's no, not really a safety risk. For a BRV failing. So when you're troubleshooting PRVs, it tends to be because you've got a leak or because there's a defect in the valve that's causing it to leak early.

As I say, unless there's something really wrong with the valve, it should not, it should not, not open. If that makes sense. Yep. So there's two ways that you can really be proactive in, in ensuring you're ready to troubleshoot something like this. So the first one here is the, the, the three way dual shutoff valve.

So this is the device at the bottom here. Now, Trevor, you mentioned before, you're, you're not allowed usually to have a shutoff valve upstream of your PRV for the simple fact that you could block it off. There is scope in. It's certainly the EN 378, the European, relevant European standard for a single shut off valve in line with the VAT and upstream for PRV.

So this is the device at the bottom here. Now, Trevor, you mentioned before, you're, you're not allowed usually to have a shutoff valve upstream of your PRV for the simple fact that you could block it off. There is scope in. It's certainly the EN 378, the European, relevant European standard for a single shut off valve in line with the VAT and upstream for PRV.

But I think it must be under lock and key and it must be controlled by a certain personnel. But we at Henry don't offer that because even then, there's still a risk that human error can occur and somebody can forget to turn it off. So we only offer the three way valve solution here. And what the advantages of this are that if you have a problematic valve or even if just a valve blows because you've had an issue.

You can switch this valve across and isolate the one that is the problematic one. You have very easily, in this case, it's a, it's a cap you remove and you just, a little spanner in and you can, you can change the flow from this angle to this angle. And that allows you to remove the valve that's isolated without any depressurization of your system, any degassing, valve off and away.

So, although As I say, troubleshooting is such, if a valve is leaking because, maybe because of chatter, or maybe because of debris in the system, there's so many reasons a valve could, could pass. Having, being proactive and having this three way valve in the system means that it's really not going to cause you any problems, because you just isolate across to the other one, remove it, now that's been sent away for inspection.

So, although As I say, troubleshooting is such, if a valve is leaking because, maybe because of chatter, or maybe because of debris in the system, there's so many reasons a valve could, could pass. Having, being proactive and having this three way valve in the system means that it's really not going to cause you any problems, because you just isolate across to the other one, remove it, now that's been sent away for inspection.

You don't have to pull out all the whole charge. Yeah, exactly. Words would be a nightmare. It means you've still got system protection as well. That's the important point. If you do the same thing with a single isolation valve, but then your system's unprotected. So something happens, you have to run away for something.

You forget to unlock the valve again, and something, God forbid, happens to the system. It's going to, it's going to be a bad one. So this means you're always protected. So with your three-way valves, is there like a, can you tell, like, is there markings on there to say, okay, you're the left one's open right now.

The right one's open. How do they tell when someone's going to switch it over? Is there, yeah, so with this design, I've not got an image on the speed unfortunately, but with this design which is our award-winning nine three series valves, there is a stem here that you've got a spanner on and it's got like a little l indication on it and it shows you which way.

The flows is gonna go. Okay. So you can see visually on the end of the stem, the older models. Some of our legacy threeway valves are a longer valves with a, a piston that cycles back and forth to shut off one port or the other. And you really just have to look at the stem and see, is it in or is it out to figure?

The flows is gonna go. Okay. So you can see visually on the end of the stem, the older models. Some of our legacy threeway valves are a longer valves with a, a piston that cycles back and forth to shut off one port or the other. And you really just have to look at the stem and see, is it in or is it out to figure?

Yeah. Backseat it or front seat. Yeah. Backseat or front seat. Exactly. Okay, cool. Again, we talked about pressure drop. These devices are things that can introduce pressure drop, so it's important to make sure that the three way valve you're using is correct for the PRV. Again, we've got guidance in our product catalog and on the online selector, as you saw there, I could select different three way valves.

It will tell you which one is, is Because again, if you have a three way valve that's too small, then it's going to restrict the flow and your, your, your relief valve is going to be affected. So important to make sure you use the right one. And the second, second thing you can do again for proactive troubleshooting is the second part of this assembly, which is the rupture disk.

Now, rupture disks are, for those of you who don't know, hermetically, they're a way of hermetically sealing a system, but still having the ability to relieve pressure. So it's a a disc in this play. In this case, it's it could be nickel, it could be different materials but it's scored with a laser very finely tuned so that it bursts at a specific set pressure.

Now, rupture disks are, for those of you who don't know, hermetically, they're a way of hermetically sealing a system, but still having the ability to relieve pressure. So it's a a disc in this play. In this case, it's it could be nickel, it could be different materials but it's scored with a laser very finely tuned so that it bursts at a specific set pressure.

And the set pressure of the disc is tied to the set pressure of the PRV, so they both work in unison. The advantages of this are that PRVs, and it's a, it's kind a common misconception. And it becomes more, it's becoming more prevalent as rightfully so. The industry is becoming more sensitive to leaks and trying to reduce leak rates everywhere.

But there's a common misconception out there that A PRV is capable of absolute seat tightness and it should never leak. Now, from a technical point of view, everything leaks you know, welded joints leak so there's always leak there. But when you think about, a PR and we're talking about welded joints.

Think that three grams a year is kind of d termed E 3 78. That's bonded around as being acceptable as leak tight. If something's three grand to three grams a year for joint leakage, and that's talking about welded joints. If you think about a PRE where you've got a Teflon seat and a, or tle, a Teflon seal, like a brass set, a steel seat, all you're doing is pushing these two surfaces together.

Like that's never going to be hermetically. It's not possible for this to be hermetically sealed, so you'll always get. In every PRV, you will get a small weep, we call it, of refrigerant through, and it's not enough to set off a leak detector, you, you know, you wouldn't notice it with any detection equipment.

Like that's never going to be hermetically. It's not possible for this to be hermetically sealed, so you'll always get. In every PRV, you will get a small weep, we call it, of refrigerant through, and it's not enough to set off a leak detector, you, you know, you wouldn't notice it with any detection equipment.

But because refrigerant is heavier than air, it sits inside the valve, and not so much with these, but some of the straight through valves, where the outlet's on top, the refrigerant just builds up and builds up and builds up over time. And if you go to that with a leak detector, it goes wild, and you think you've got a big leak.

Because you've got this pool of refrigerant that's built up and that causes issues. And if you blow it out with some air and then test again, you won't find a leak because it's not leaking at a rate, but you've got this, this issue. So the beauty of a rupture risk is that you've got this hard seal. It's a hermetic seal.

And what it does is it completely isolates the PRV from the system. So the PRV doesn't even see the gas. So it's, it's the ideal solution because the PRV thinks it's sitting on the shelf somewhere. So it's, it's nowhere near the gas until. It needs to, it needs to see it until it bursts. So the rupture risk bursts, the PRV the same time.

And what it does is it completely isolates the PRV from the system. So the PRV doesn't even see the gas. So it's, it's the ideal solution because the PRV thinks it's sitting on the shelf somewhere. So it's, it's nowhere near the gas until. It needs to, it needs to see it until it bursts. So the rupture risk bursts, the PRV the same time.

Obviously the rupture risk is gone. It's, it's open. So the fear of PRV is the thing that gives you the. The reseal again, and then you've got it on your three way valve, so you can easily switch the valve across, change it in for a new one, and and no issue. So, those are the two things. Your three way valve allows you to maintain valves and switch valves out really easily, and your rupture disc gives you that.

It's the only solution that'll give you complete leak tightness and give you that peace of mind that that there's no weep occurring anywhere in the system. Yeah. Yeah, Stephen threw in the chat and you know, it's worth mentioning that you should only have one live. PRV at a time. So if you're mid seated, for an example, and the pressures build up, you're going to blow both reliefs not just one.

You are. And again, I've seen that again, it's it's information that we need to spread. So thanks to Steve, you said, put it in the, in the, in the comments, because it's the kind of information that people do think, well, I've got two valves. So I should put it in the middle of them. They'll both be active.

But if you think back to what we talked about to do with floor and the pressure drop. Yes, you're going to open both valves, but you've got half the port either side. So neither valve is going to vent properly because you've restricted the flow. So yes, it should always be in either one valve or the other fully seated to one side of the other.

But if you think back to what we talked about to do with floor and the pressure drop. Yes, you're going to open both valves, but you've got half the port either side. So neither valve is going to vent properly because you've restricted the flow. So yes, it should always be in either one valve or the other fully seated to one side of the other.

Never, never in the middle. Yeah. Thanks Steven. So now I want to ask some questions because you had a good point there. So they're going to, if you just have a spring type, it's going to leak a little bit, you know what I mean? So you go up with your leak detector, pick it up, you blow it out. And then all of a sudden there's no no leaking.

I, I have this question for people. Well, if it's on the roof and you're outside and it rains or snow, and that fills up with water, how does that affect? The PRV, if it's in the elements like that. Yeah, so you should always avoid, avoid that the valve filling up with water, especially, or snow, even worse because again, that's, that's affecting the back end of the valve, the spring, especially and especially straight through valves where it goes in and fills up and you've, you can get corrosion on the spring, which will reduce the set pressure.

So again, you don't want to have any restriction on top. I've seen some people leave caps on the top, plastic caps thinking they'll blow off in the event of a. Discharge, which they may, but if they're tight, they may cause the valve to suddenly reseat again and jam and things, and it's, you don't want to do that.

So again, you don't want to have any restriction on top. I've seen some people leave caps on the top, plastic caps thinking they'll blow off in the event of a. Discharge, which they may, but if they're tight, they may cause the valve to suddenly reseat again and jam and things, and it's, you don't want to do that.

So ideally you'd have like a little elbow or something on the top of the valve. So that's a, that's a great one because that's what I used to do. Like I used to, you know what I mean? Like I just leave the cap on there, red cap or orange cap, so you shouldn't do that. You shouldn't. Only if it's literally.

Like, and it's just sitting on there and you can blow that off though, you know what I mean? If it's outside, well, exactly. So you're better with an elbow is the best. But yeah, if it's, if it's indoors or something, you want to protect from dust and the cap on it, not tight, but, but the cap's really just there to protect the threads in transit.

It's not designed to and although it's, it's easy to think, well, the force of air or gas is going to blow this off. It's amazing what that initial moment of Back pressure that it sees when it opens can do, it can force the valve to close again. And then maybe the cap comes off, but the valve's already kind of stuck itself, and it gets into this weird, it's strange because it can actually affect the set point as well, which is, it's almost counterintuitive, you think it opens and closes, but it kind of closes with such force that it bites into the seat more, and it can actually make the valve set higher.

It's not designed to and although it's, it's easy to think, well, the force of air or gas is going to blow this off. It's amazing what that initial moment of Back pressure that it sees when it opens can do, it can force the valve to close again. And then maybe the cap comes off, but the valve's already kind of stuck itself, and it gets into this weird, it's strange because it can actually affect the set point as well, which is, it's almost counterintuitive, you think it opens and closes, but it kind of closes with such force that it bites into the seat more, and it can actually make the valve set higher.

It's, it's really strange. I didn't know that. And okay, here's another question. I used to put like when I was in the field, like, Oh, I'm not sure if it's legal or not put a balloon over it. Is that a bad thing to do? No, no, no. No, I told her that I'll definitely show you if it's leaking, because if the balloon inflates a rate thing, you've got an obvious leak.

In fact, when I first joined Henry before we have the. The new test system we have at the moment, that's what we use to test valves and to see when they were, when they were opening was to have the valve on the test rigs, increase the pressure, a little finger caught a balloon or something on top.

And once it starts inflating, you know that the valve's lifted. Nowadays, we've got remote. Equipment and more, more high tech than that, but yeah, it's, it's a valid way. So it's the old, the old fashioned ways. Yeah. Easiest. Okay. And another question. So if I have, so I like this this way, what do we call this?

And once it starts inflating, you know that the valve's lifted. Nowadays, we've got remote. Equipment and more, more high tech than that, but yeah, it's, it's a valid way. So it's the old, the old fashioned ways. Yeah. Easiest. Okay. And another question. So if I have, so I like this this way, what do we call this?

Is it a trunk or is it a tree? What's this setup that you have? I've heard people call it. We call it a safety device assembly, but you could call it I like that Safety device assembly. That's perfect. So if I have a relief on this example, so we've got the three way valve, we've got the rupture disc, we've got the spring.

You said if the rupture disc goes, it's a, it's a one shot deal, right? You know, you know, so that opens up, but if that spring opens up and then it's set seats back down, can I reuse that one that open, or do you recommend replacing that one? We always recommend replacing them. The, again, something else that's going to.

Not, not misconception. It's just something that's not really publicized a lot is that PRVs are so sensitive. They're designed to be sensitive. That is the point because normal valves, as you know, a non relief valve will open you know, slowly with pressure and then closely again, PRVs are designed in such a way that a small increase in pressure will bang, will lift the valve very suddenly, and that's all down to the internal aerodynamics and things.

Not, not misconception. It's just something that's not really publicized a lot is that PRVs are so sensitive. They're designed to be sensitive. That is the point because normal valves, as you know, a non relief valve will open you know, slowly with pressure and then closely again, PRVs are designed in such a way that a small increase in pressure will bang, will lift the valve very suddenly, and that's all down to the internal aerodynamics and things.

But once it comes back down again, because of the sudden opening, you often get a sudden closing again, and that, that, the force of that re closing action can affect the set point. So the valve, the valve will, will lift again, but we, you can't guarantee that it'll be within the, there's a plus or minus 3 percent tolerance on set point of valve.

So you can't guarantee that after the massive force and all the debris that's probably been blown across the seat from the, you know, the particles inside the system, that all affects the ability of the valve to seal. So you should replace it. So we'll give an example here. So if just say it's a hundred bar, PRV, it opens up and it closes by code.

It cannot go open below 97 or 103 one. One or the other. That's the 3% 97 bar or 103? Yeah. Or 1,450 PSI plus or minus 145 psi. Yeah. And, and. Again, with relief valves, nothing's, nothing's ever simple. So, so there's, there's a, there's a number of things a PRV has to achieve pressure tolerance wise.

It cannot go open below 97 or 103 one. One or the other. That's the 3% 97 bar or 103? Yeah. Or 1,450 PSI plus or minus 145 psi. Yeah. And, and. Again, with relief valves, nothing's, nothing's ever simple. So, so there's, there's a, there's a number of things a PRV has to achieve pressure tolerance wise.

There is a, a leak tightness test. So starting at the bottom end, there's a leak tightness test, which again, the standards leave it open to the manufacturer to determine how they do a leak tightness test and what pressures are involved, 527 standard. Which is a seat tightness standard so the loop tightness test that we do at Henry is at 90 percent of the set pressure.

So up to 90 percent of the set pressure there should be no leak on. The API 527 method, which is basically the outlet of the valve gets connected to a tube, which goes into a a beaker of water, usually. And then we look for bubbles on the outside of the tube. So at 90%, you should have no bubbles from the tube.

Between 90 percent and the bottom end of your tolerance, which is 97% bubbles would be allowed, but up to the second. point definition. Now, again, set point definition is another thing that's different. Manufacture the code, leave it, leaves it frustratingly open for different manufacturers to use different set point definitions.

We use, again, using that method, a minimum of one bubble per second coming out of the tube. We say that's when the valve is set. You get manufacturers that use pop as set. Like the valve will be set when it pops. You get manufacturers that use first audible, which I find astonishing that the first time you hear the valve is when it's set.

We use, again, using that method, a minimum of one bubble per second coming out of the tube. We say that's when the valve is set. You get manufacturers that use pop as set. Like the valve will be set when it pops. You get manufacturers that use first audible, which I find astonishing that the first time you hear the valve is when it's set.

So you actually have to be listening to the valve. And if that thing goes off your breast, bursted eardrum, but this is what some people use as, as the definition. So anyway, It has to be set within that minus, plus minus 3%. That's when the, whatever your definition of set point has to happen within that plus minus 3%.

And then 10 percent over your set pressure is the point at which the valve, it has to be fully open by then. Usually the valve's fully open before that. Ours typically get fully open about five or 6 percent above set pressure. So it'll start to bubble. at your, within your 3%, and then at some point, around about 5 or 6%, it'll go bang, and you'll be fully open.

But when they flow test valves, they flow test them at the 10%, because that's the worst case, so that's where the valves flow test and rated at. So that's your, that's your stages, if you like, of what a valve acid is. That's huge. Like I learned so much there. So now you like valve manufacturers. If one here I'm here in Canada, it goes off here in Canada and then it seats.

But when they flow test valves, they flow test them at the 10%, because that's the worst case, so that's where the valves flow test and rated at. So that's your, that's your stages, if you like, of what a valve acid is. That's huge. Like I learned so much there. So now you like valve manufacturers. If one here I'm here in Canada, it goes off here in Canada and then it seats.

And then it's depending on how, how fast it goes off, how quick the pressure goes up and that, that receipts. And then you're out in New Zealand and it goes off the same valve, same manufacturer off the same line, the one beside the other. Doesn't mean it'll be the same percentage afterwards, like, and that's why you recommend and I, every manufacturer I talked to, if the relief goes, you should, that I've talked to, it should be replaced or repaired.

I do have someone who asked the question, can these be repaired? Yes, you can. Yes or no. Again, nothing straightforward none of our valves are designed to be repaired. So all of our valves are sealed once they leave the factory and you can't, you can't replace the components. You do get typically larger industrial valves when again, with it in North America, the ASME code, it's an ASME, oh, it's, it's a U, no, you'd interrupt it.

I do have someone who asked the question, can these be repaired? Yes, you can. Yes or no. Again, nothing straightforward none of our valves are designed to be repaired. So all of our valves are sealed once they leave the factory and you can't, you can't replace the components. You do get typically larger industrial valves when again, with it in North America, the ASME code, it's an ASME, oh, it's, it's a U, no, you'd interrupt it.

There's a stamp anyway that you couldn't get to say that you're on the official ASME valve. Repair maintenance laboratory and you you're a license to repair the valves. But with our valves no, they're all Oh, that's that stuff is huge. So that there so if you're in the field and it it does go and you have a Leak on that one side that should be replaced It's it's very important and because it the big thing is looking at that rupture disc That should be one thing.

Okay, if you have a real leak or you're picking up a leak Go look at the rupture disc if they're on there and it'll give you an idea. You knew it leaked Switch it over, ordered a new a new assembly, not the full assembly, but just the rupture disc and the spring, the spring, get the same ones, you know, you don't want to oversize or undersize them, get the exact same ones, order those up and protect your customer.

Cause this protects everybody in that system. Yeah, well, I should have mentioned, obviously, you can see them here and you indicated it there Trevor, is that they're up to risk and our safety device kits come with these indicator gauges. So there's a little, it's difficult to see on the screen, but there's a little yellow arrow there that will.

Cause this protects everybody in that system. Yeah, well, I should have mentioned, obviously, you can see them here and you indicated it there Trevor, is that they're up to risk and our safety device kits come with these indicator gauges. So there's a little, it's difficult to see on the screen, but there's a little yellow arrow there that will.

Ping up to the, the, the pressure when it sees pressure and it doesn't tell you how much the pressure is, but so you can see visually straight away, which valve is gone. And if without looking at the valve, without looking at the three way valve to see like which side is lying, you can see because the indicator gauge will be up saying there is pressure on this line.

And so it's an easy way to to show which one's gone. Yeah, no, that's, that's awesome. I love this. Like I've learned so much already. It's not that's, that's that. Well, I've got so many slides, but effectively just the key points and that we talked about, which again, I won't go through them. Everyone, everyone can see the slides and, but yeah, we, we talked through everything today and hope it was, hope it was useful.

Oh, this was super useful for me. Like I think Just that those troubleshooting points is very, very important because we like as technicians in the field, we don't see this a lot, especially if you're a service technician, we're going around, we're doing the leak detection. Okay. We've seen it. It was, it leaked, it ruptured.

It had a pop off, whatever it is. Our job is to make sure the leak is done because you always got to fix the leak, you know, pressure relief is the valve or it's Fitting that leaked, we got to fix that stuff and we repair it. And then we got to charge it back up, but diving in a little bit deeper and understanding why you're doing this.

It had a pop off, whatever it is. Our job is to make sure the leak is done because you always got to fix the leak, you know, pressure relief is the valve or it's Fitting that leaked, we got to fix that stuff and we repair it. And then we got to charge it back up, but diving in a little bit deeper and understanding why you're doing this.

And, you know, I like that rupture disc, understanding what that is. If it relieves, we know that spring is not the same and the it's not going to hold the same as if it's brand new. So it's good to, to really understand that stuff. I love this. How can people get ahold of you, Jordan and your team? If they, they want to find out more about Henry group and what, what you guys have to offer?

Sure. So our general, again, the website probably nowadays is the easiest way we're on. We're on socials as well. And I think on Facebook, on LinkedIn as well, you can get ahold of just. Search for Henry Group, Henry Group Industries. The email address there is our general contact contact. uk at henry group.

net. That's us in the UK, obviously the Henry Group is global, and that's our phone number as well. You can get a hold of me directly, it's just my name all our email addresses at Henry are just our names, so jordan. gronkowski at henry group. net. And if anyone's got any questions they want to get in touch with, that's fine.

net. That's us in the UK, obviously the Henry Group is global, and that's our phone number as well. You can get a hold of me directly, it's just my name all our email addresses at Henry are just our names, so jordan. gronkowski at henry group. net. And if anyone's got any questions they want to get in touch with, that's fine.

And I can put you in touch with, if I don't know the answer, I'll find the person in any of it does, and we'll get back to you. Yeah, just check out the website. That's that's that's and the socials, that's the best way. Yeah, I definitely think you you had the knowledge and I really appreciate you taking the time to share, share with us, because this is a topic that a lot of people are PR pressure releases is boring.

It's like, I don't need to know that's the engineering stuff, but still as a technician, we need to know this stuff. We need to have an understanding of every component in the system when I'm doing CO2 trainings, because I've trained a lot of people, thousands of people in CO2 over the last few years. And, you know, you need to know every component just because it's not a component that's working every day, but actually it is working every day.

It's in place there for those times that the pressure does build up, or you have a catastrophic event, or someone closes the wrong valve to open up. And this is not only for CO2 systems. This is HFC system, HFO system, industrial ammonia system. So understanding this is very, very important. I've got a question, a great question during a commissioning pressure relief test.

It's in place there for those times that the pressure does build up, or you have a catastrophic event, or someone closes the wrong valve to open up. And this is not only for CO2 systems. This is HFC system, HFO system, industrial ammonia system. So understanding this is very, very important. I've got a question, a great question during a commissioning pressure relief test.

Should there be a valve be replaced after test? Okay. So when you are doing a pressure test in a system, you have to blank off them or remove the pressure relief valves. Because here in Canada, the standard is, is that it's one. 0. 1 times the design pressure same as B 52, the same with as me 31. 5. It has to be 1.

1. So for an example, if you have a a 1740 PSI, which is 120 bar system, you have to do 1. 1 times that. So you will have to blank off that. You have to actually remove it. Pressure test, everything upstream of that pressure relief above that. Pressure test, because just remember, we're trying to protect the pipe, the components in the system.

So whatever that, that pressure is, all those components have to be, handle the pressure higher than the pressure relief valve. Anything you want to add to that Jordan? No, it's, it's the same here and EN 378 is our standard. And again, it says PRB should be isolated or removed for, for system pressure tests.

So whatever that, that pressure is, all those components have to be, handle the pressure higher than the pressure relief valve. Anything you want to add to that Jordan? No, it's, it's the same here and EN 378 is our standard. And again, it says PRB should be isolated or removed for, for system pressure tests.

Because yeah, you, you're going to blow the valve if you do. The other thing maybe to add slightly onto that is we, a question we often get asked and some people have the requirement is to, should I test the valve before I put it on the system to, to make sure it's working, make sure it's okay. And we, we always say, no, you should never test the valve with a third party because Because valves are so sensitive, it's very easy for you to, to do a pressure test with the best of intentions, but actually the test in itself modifies the set point of the valve, and you can get a false positive and a false negative.

And as I said before, every manufacturer has different definitions of what the set point is, so you could be testing, looking for a bubble when the valve, from this manufacturer is actually set when you can hear it or, you know, vice versa. So if you have to do a test on a PRV, again, the EN 378 standard says that each valve should be tested for seat tightness, and before it goes in the system, we as a manufacturer do that in house.

And as I said before, every manufacturer has different definitions of what the set point is, so you could be testing, looking for a bubble when the valve, from this manufacturer is actually set when you can hear it or, you know, vice versa. So if you have to do a test on a PRV, again, the EN 378 standard says that each valve should be tested for seat tightness, and before it goes in the system, we as a manufacturer do that in house.

So you do not even have to do that. But if, if you have to. feel like you have to test something or if you're your notified body or whoever, your, your inspector wants to see a valve tested, it should be the seat tightness test you do, which is the 90%. You should never take it up to, to lift the valve. Certainly the Henry valves, anyway, are other manufacturers.

Some, you do get, again, industrial valves with lifting levers, you can be used to test them and things but our valves should not be, should not be tested. And so that's a great point. So 90%, if you're doing, doing that, so once again, if it's a hundred bar or 1400 PSI, you'd go up to 90 bar. Correct. So that's the action you gonna do.

That's your, and and again, you're looking for a leak as pair, the manufacturer's definition of leak tightness. So for us it's that tube into a bottle and you're looking for zero bubbles. Different manufacturers will have different. Definitions and requirements. So it's, it's, it's a, it's a main field, especially from a, from a, you know, from a, from a, the end user's point of view, like, what do I do with my valve, but I can only speak for Henry, but for us, we do all the tests that are, that you need us to do, or you need to have done in the factory.

That's your, and and again, you're looking for a leak as pair, the manufacturer's definition of leak tightness. So for us it's that tube into a bottle and you're looking for zero bubbles. Different manufacturers will have different. Definitions and requirements. So it's, it's, it's a, it's a main field, especially from a, from a, you know, from a, from a, the end user's point of view, like, what do I do with my valve, but I can only speak for Henry, but for us, we do all the tests that are, that you need us to do, or you need to have done in the factory.

So when you buy a Henry valve, you know, it's all been done. Yeah. I got another good question here. Can you give me a thought? Is there a torque spec for installing a PRV? On onto a system. Eh, it will depend on the thread. That's another good question actually, but it's something we get asked a lot.

Most of our valves, like 99 percent of our valves, apart from a few specials that we do, are NPT threads, so tapered thread connections. Now there is no recommended torque for NPT because torque is not a good measure of how well an NPT connection is engaged. So no would be the simple answer because it's an NPT thread.

NPT threads, it's turns past finger tight, is the guidance. You can find Guidance all over the place of the internet and Google Google what it is. We've got some guidance in our literature as well. But yeah, you take it a finger tight and then it's so many turns. I think for, it depends on the thread size.

NPT threads, it's turns past finger tight, is the guidance. You can find Guidance all over the place of the internet and Google Google what it is. We've got some guidance in our literature as well. But yeah, you take it a finger tight and then it's so many turns. I think for, it depends on the thread size.

It changes, but it's, it's between like two and three turns past finger tight, I think for most, most thread sizes. If you have a Parallel thread, which again, some of our valves have that for special applications and some other manufacturers offer, offer that standard then yeah, there probably will be a torque setting, but you should contact the manufacturer and ask them for the, it should be in the operating instructions to be fair for the, for the valve, but if you're not sure, just contact the manufacturer.

Do you, okay, here's another question on it. Cause that was a great question. Do you recommend Teflon tape or thread lock on them? Any of your valves are just hand tightened. And like you just mentioned. Again, we're, we don't mind different refrigerants can react differently with things like thread tape.

As it is. 410A, I think, has an issue with PTFE tape, and it can break up the tape. I might be wrong on that, Cindy, you'll probably correct me in the chat. So it's important to know what thread locking compound you need to use to match your system, if you like. When we test valves on air and gas at Henry, or when they go to the National Award Labs in America to get tested, it's typically PTFE tape they get wrapped in.

As it is. 410A, I think, has an issue with PTFE tape, and it can break up the tape. I might be wrong on that, Cindy, you'll probably correct me in the chat. So it's important to know what thread locking compound you need to use to match your system, if you like. When we test valves on air and gas at Henry, or when they go to the National Award Labs in America to get tested, it's typically PTFE tape they get wrapped in.

So there's no, there's no there's no Perfect preference to threadlocker. The important thing is to make sure, especially if it's threadlocker compound, that you don't get any in the valve. Only apply it to the external male threads of the valve. Don't be too liberal with it. Just a couple of threads worth and tighten up.

Make sure it doesn't weigh in because if it gets in there, it can You can put it on the valve seat, which obviously can affect the set pressure and worst case scenario could stick the valve and if you've poured it in there, which is but yeah, so just be careful using threadlocker compound that doesn't get into the valve. Love it. Oh, Jordan, thank you so much for taking the time to hang out with us, share some knowledge and I'll see you all next week at CO2 experts. Thanks. Thank you very much.