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You do need to hold on to your receipt from whoever you purchased the combustion analyzer from, but of course we suggest, if you don't have a local supply house that stocks these you can easily go to true tech tools, comm pru tech tools, calm and use the Offer code get schooled and you'll get an additional 8 % off then just save your receipt that you get from true tech tools go to HVAC our school comm 4 slash, fall, promo and fill out the form, and you will get either a free, 770, 3 meter Or a 745 non-contact voltage sensor from test OU t'est, OU, 60 years of excellence, perfect for testing perfect for service, and now the man whose body odor has been deemed at ozone-depleting substance according to the Montreal Protocol, Brian or may yes, this is this is Brian and Thank you for listening to the HVAC school podcast thanks for being here and the HVAC school podcast is actually actually lives on HVAC our school comm. So if you've listened to the podcast and you've never been on HVAC our school comm, then I don't know what you're waiting on there's a lot of people who I have talked to who are like yeah. I follow your Facebook page or I see in the Facebook group or I listen to the podcast or I've read the tech tips, but the truth is, is that HVAC? Our school is all of those things and the website is kind of the center point of that. So that's HVAC our school comm, that's my little, my little plug for the website.

If you been there recently, I actually had somebody somebody in the Facebook page who I shared an article and he clicked the article. And then he wrote on Facebook that that he was gon na. Read the article but shame on me for having an ad asking for his email and I was like well, it isn't really an ad it's just asking for your email in case you want to get the daily tech tips to your email, but if you don't want To just hit the little X X button, I don't I don't know why that's so difficult but anyway, so that is one of the first things you might see. If you go to HVAC our school comm is a pop-up and the pop-up just says: hey.

You want to sign up for the daily tech, tip, email and, if you do want to, then we will send you a daily tech tip. It's not like I'm gon na be sending you. You know marketing buy something from me or anything like that. That's not how that works.

It is a daily tech, tip email. When I say daily, it's not like seven days a week, it's probably more like five. I think I never J, I'm averaging about five articles a week and it's not only written by me. I read a lot of them, but they're also written by a lot of other really cool people like Justin, Skinner and Jeremy Smith and many others.

In fact, I even I even get Jim Bergman to contribute some some stuff, so he's he's a little he's. A little more tricky to get, but anyway, today, on the podcast, we have a three-time guest on the podcast, and that is Jeff, Niemann and Jeff diamond is a chiller tech and our really down-to-earth chiller tech he's not like one of these super Tech's. It thinks he knows everything but he's a guy who's working on a lot of chillers, and he knows a lot about chillers and one thing that I know very little about again. You know everything with chillers, I know very little about, but I know very very little about low pressure.

Chillers and I've always been fascinated by it. Ever since my instructor in AC school dumped, some are 11 in my hands and I was able to watch the r11 boil off, which is patently illegal, but I didn't do it. It was my instructor, I'm not gon na name any names, but ever since then - and he was explaining - you know, low pressure chillers to me, and - and I was fascinated by that - and the fact that the low side of a low pressure chiller is actually below atmospheric Pressure so of course that creates some issues and and Jeff said well, let's talk about leak detection on low pressure chillers, so today's podcast is on leak detection with low pressure chillers, and so here we go Jeff diamond and leak detection on you guessed it low pressure. Chillers, I'm in my van and it's raining out, so I don't know how the sounds coming through on my end here.

How does it sound to you Jeff? How does it sound to you? You know it's it's very peaceful. It really is it's nice, just in the rain, you know, I'm glad I caused it. First, you sound a little stressed out. You know actually very happy that we're doing this day cuz.

It gives me about a solid hour to where I can't break anything. So that's good! Oh at least I got that going for me. Yeah, you can't break anything like out of anger, can't break anything, no just normally when they touch things. You break a big dumb animal okay, so you just you just touch objects and they break at this point.

I just have to look at them. I don't even have to touch them anymore with that being said, this being my third time doing the podcast, I'm looking forward to visiting my self-portrait in the Hall of hva school podcast, HVAC school, the pretend corridors of our pretend Palace, where we keep the honored guests, You will be forefront, it will be so if you look to your right, you'll notice, the photograph of Jim Bergman. If you look to your left, you'll see Nick Messick and to the right over there you'll see Jeff Niemann, that's high praise, I'm very flattered uh-huh should be alright. So today, on the podcast, we have Jeff third time's, the charm Neyman and we're gon na be talking about leak detection on chillers and not just any chillers mind you on special chillers.

That's a variable, there's special chillers, all right! So, first off I always have to ask you you do the type of work that I have always kind of wanted to do. Have you done anything interesting today or one the last few days? Let's see it's all kind of interesting today I had a system where they have glycol leaks all over the place, so that's fun and they don't have the time to shut the chiller down and fix the leaks, so basically we're just adding glycol to it as it's Leaking out, if you try putting a see leak, fries in it, I have not. I will remind that to them and yeah. Instead of actually sticking the injector like feeding it, you actually just stick it right where it's leaking, just let it in there yeah all right.

I'm writing that down one more okay good. It won't hurt anything because it's an oil-based product, okay, ignore all that last stuff that I said it being sarcastic okay, so glycol leaks all over the place yeah, my colleagues, so the chilled water pump on the suction side is running into a vacuum, and it's introducing Air into the system, through the shaft seal, which is introducing more leaks, because now the air vent is trying to purge out air, that's getting into the system and we're at least in glycol with that as well. So it's just going around around casing our tail. Trying to keep this thing and in working order form, and so we can do the proper repairs on it, got it so proper repairs are shutting it down and actually repairing the leaks, properly yeah, and I'm actually here enough to do repair on another chiller.

Actually, this is a question that I posted to the ATA school podcast page Facebook page with the vibration absorber, on a compressor so where the piping to an 1/8 inch, copper piping, etch, the fitting actually cracked after the vibration absorber. So I'm gon na redo the whole discharge line and install the absorber in the proper way and hopefully take care of that mess. What was improper about how it was installed? It is installed perpendicular to the axis of the shaft of the compressor, and it is also installed as a riser and there's no piping support after I've got it where it's installed, so basically stretched it out over time and it doesn't work. No more.

It's broke. It's broke, they did it wrong and it's booked something wrong, definitely yeah all right. So when we're talking about leak, detection on chillers, which is what we're talking about today, there are chillers that are very typical in the way that we do leak detection and that they are all positive pressures. So let's do that again.

So for those of us who know nothing about chillers, let's talk about the two different typical types of chillers as far as as far as pressures go. That was a really bad way of introducing that just go ahead, and you know what I'm trying to say: yeah, no for sure yeah I mean there's chillers that work with pressures just like every other piece of equipment out there with a positive pressure of 134a r22 For 10a and the smaller chillers and regarding those usually check those just like any other package, another residential type system, then you have the low-pressure chillers, where the operates yet even standing idle, not an operation that they're sitting in a vacuum. They are below atmospheric pressure and that's gon na be refrigerants 123 r11 and see where cases just associate some r11 out there and leave checking those are little more time consuming than your high-pressure machines all right. So, as far as the types of machines generally, the high-pressure machines are going to be usually screw chillers right.

In most cases, yeah screw chillers are actually yeah pretty much all secure chillers that I've run into are all high-pressure there's chillers that have scroll Copeland, scroll compressors. On them - and those are all high-pressure in my experience, doing low pressure chiller that I've run to is a significant type of chiller and that's gon na be either a train or a York in. Although York York doesn't make any low-pressure choice, anymore, trains, actually the only manufacturer that still makes those. In my experience really yes, this is the only centrifugal chiller static did it be made currently are trained.

Well, that are low-pressure, okay yeah. So there are high pressures and drivel trailers, yep yep, your carrier, McCoy they're, all 134a and the nor once as far as centrifugal goes so and the air-cooled side, but again they're gon na be either 134 a or 410 a you'll see on the scroll, not a School chillers, alright, so I want to address real quick, so I'm just gon na take this little piece here cuz. This is something that I know which is rare, that I know something. It seems like all my guests come on.

They know all the stuff, and I don't know anything anymore - I'm like a big dummy. I need to do some more solo episodes so that way I get to getting some respect back from my audience, but so the one thing I understand is that so at atmospheric pressure at sea level, pressure is 14.7 PSI a and that's the pressure of the atmosphere. All around this, and so I think we tend to think traditionally when we think of a high pressure system. We think when the system is at zero, psi G, which is zero pounds per square inch gauge that there's no more refrigerant in the system.

We've achieved atmospheric, but that is just patently false. So you, when you are at zero psi G, which is when we were looking at our typical gauges and they say: zero, there's still 14.7 PSI a of whatever matter is inside that system. So you can have a system that has a lot of refrigerant still in it, for those of you who are universally epa certified. So that means you have your class three.

The epa guidelines go over this, a lot that you have to understand that and low pressure systems. You are functioning almost exclusively or at least on the in the static state and we're in the low side state you're functioning below atmospheric pressure, so you're dealing with massive amounts of refrigerant all below zero psi g below atmospheric pressure. So the key thing i'm wanting to get to here is that, just because you see zero on a gauge unengaged, that's a gauge scale does not mean that there's no refrigerant present anymore, which is also true on a high-pressure system. When you take a system - and you get it down to say, you pump a system down to zero psi g and you open it up.

That doesn't mean there's no refrigerant in that system. There is still refrigerant in that system and that's why, for certain systems, the epa has guidelines that you have to pull it down into a vacuum, to actually get out the rest of that refrigerant, with low pressure, some difficult, chillers being a key place that that it Would be necessary, so i just want to explain that real, quick, just cuz, you see 0 doesn't mean no refrigerants is present, and so now we're gon na go into. If you were to run into a pressure centrifugal chiller. What would you have to do? Well? First of all, let's cover this.

What would happen if there was a leak? Let's say there was a leak on the low side of a centrifugal low-pressure system. What would happen a low-pressure chiller, where leaks are presents. Low-Pressure chillers have a separate purge. You nuts installed on the chiller itself, and the purpose of the purge unit is to get rid of non-condensibles that enter into the system and typically it's not a huge problem.

The purge will take care of any real small leaks that happen to be there in the system, but once that leak or multiple leaks get large enough to where the purge cannot overcome the leak rate, then you have problems and you you're introducing excessive non-condensibles into the System, your head pressures go up, your heat transfer and your condenser aside from the refrigerant to the condenser water reduces, so your approach, temperature will increase and the operating envelope of that compressor will be exceeded. So the lift pressure, which is your difference between your suction and your discharge, pressure centrifugal compressors, will have a design lift pressure and I vary from manufacturer to manufacturer and there's a lot of variables that play into there. But once you exceed that that envelope of what it can do, it will start surging, no will have a stall and it will surge and the surge is just basically a reversal of refrigerant flow within the compressor itself, which is not good, and you know when they're Surging because they will be screaming at you pretty loud, they tell you so when we think of leaks in a low pressure, centrifugal chiller, it's not refrigerant, leaking out, at least on the low side of the system. It's not refrigerant leaking out.

It's our atmosphere or air. Entering so it's the opposite of what we would typically think of it. So you end up with this additional air in the system, which then displaces the refrigerant. It's a non condensable gas, and so it causes issues in a system similar to what a non condensable gas would cause in a typical high-pressure system.

But, unlike a high-pressure system, it happens dynamically, meaning you continue this non-condensable gas ie air into the system, the more that it runs correct. Yes, that is they say anything incorrect there. No, no, that's very accurate. It leaks a low-pressure machine, yeah you're in Russia, Arab, but when the leak becomes excessive, there will also be refrigerant loss through the purge unit itself, a dirty little secret.

That comes with the purge units that doesn't get published in manuals and books. The literature is that our guests, until more pipe or podcast but every time a purge unit, events non-condensibles, there's always a trace amount of refrigerant that gets carried away with it and they do a pretty good job of separating most of it under normal conditions. But when you have excessive leak and you have excessive purging going on, there's always some refrigerant that gets vented out with it and one of the safeties that are with these low-pressure machines, whether it's a train or York, there's max purge times or first counts within a Set amount of time, whether New York, it's a maximum purge, counts per hour and on a train chiller, it's it's max purge time per day. You know it's just different way of that they have them set up, and so that's kind of a safety to where it almost seems counterintuitive, because they'll shut the purge down if it's venting or purging excessively, but it doesn't help the matter.

If, if you have a leak and your purge tops down - and it just makes everything even worse so start shutting it down because it doesn't want to either a vent excessive refrigerant or I'm guessing when it shuts down it's alarming and telling you that this is occurring And so it's more likely that it's then going to be fixed right yeah! It's basically telling you hey we're we're purging way too much. We have a leak going on somewhere and it's a way for you know, then, as a to notify the operator or the technician that something's going on and also a way to prevent excessive refrigerants purging out to the yes, sir, just a couple quick things to mention Here one thing that I want to mention is that well, I've seen an increase recently in different municipalities, different locations around the country around the u.s. enforcing the installation of locking caps on new installations of systems, and so I'm gon na just suggest to you that if You haven't started installing locking caps that maybe you just start doing it now, a lot of people bring up that they don't like having to have the special keys for the locking caps, but the truth is: is that as other companies begin using these keys anyway, these Caps with the special keys from rector seal you're gon na want to have these keys on your keychain anyway, and rector seal makes a great product. It's called the no vent product of locking tamper, proof caps, and then you get the little keychain ring that goes right.

There on your under keychain and then, if you ever run into a no vent cap, you've got that right there on your keychain. So it's a good thing to have a good thing to be prepared with, even if you are not yet installing them go ahead and pick up one of those keychain keys. So that way you and your technicians are prepared. Another thing that I want to mention from our sponsor carrier and again those of you who don't know I'm a carrier dealer we install carrier products all the time, I'm really surprised and surprised and delighted.

I guess I shouldn't say, surprised and delighted that they are really committing to the ductless line. We've installed a lot of decals over the years, but over the years we have not installed a lot of carrier ductless, but lately we're installing more and more, and I am really surprised by the quality of the product and it really it's improving one thing that I Really, like the carrier's doing, is they're focusing on the serviceability of their air handlers because that's always been a challenge getting to the blower wheels getting the the units, apart with a lot of the other brands. If you've worked on Douglas, you know exactly what I'm talking about in carriers, making some really big strides and the ability to service and access those of a perk, whales and those blower wheels and one of their new products. You actually can take the entire blower compartment out with just four screws, which i think is pretty awesome, so carrier turn to the experts.

Another product that I want to mention, who is they are not a sponsor at all, but it's a product that I really think is cool that I think you should know about as part of this little little segment here and that is the pipe wiper product. That's made by a Jack's manufacturing, so you just type in a Jack's manufacturing comm and you go to their website and they have this product called the pipe wiper and what it is. It's just a system, a very simple system for you to push wipers. They they call them, but they're, really pigs.

If you're familiar with how you can you know, force pigs through a line in order to clean out of line to flush your line set if you're going to keep an existing line set instead of flushing it with solvents. We've used solvents for years, we've used different products that are out there on the market commercially available, and the problem with a lot of these solvents is. First of all, some manufacturers are starting to say: hey. We don't really want you using them, because we're afraid that you're gon na leave a residue in the lines there's that concern the other thing is most of them, are pretty nasty, get them in your eyes, get them on your hands.

They're, not the not the greatest thing, and the other thing is just having that stuff dumped on the ground isn't always the best either I mean let alone that you're not supposed to dump it on the ground, but if it damages customers, you know sidewalk or damages Or plants or whatever that solvent stuff, just isn't, isn't the best, so if the pipe wiper doesn't use any solvents, all the does is just force that that pig that wiper through the lines you just use nitrogen to do it. We find that it saves time, saves money, you know, because the flush solvents are actually pretty expensive and it works great. The concern that a lot of people have is that it's gon na get stuck, but we show pretty pretty well that it doesn't. That's not the case we actually forced to through a line set.

That was a second-story application and went through just fine. We did that by accident by the way, but he also demonstrates on his website. You can swatch them his videos where he forces it through kinks and short radius, 90s and all sorts of situations like that. So you can find that by going to a Jax manufacturing and he actually set up a discount for you as well.

It's the same one that we used for tech tools, it's gets cooled and you can use that to get a discount at checkout. So that's on the low side of the system, but on the high side of the system, you are above atmospheric pressure. Correct. Yes, most cases you are in a positive pressure on the condenser side and when it's an operation, we can leave check that just like any other chiller with your electronic detector.

Whatever you happen to be using, but on the low side is still be low, atmospheric pressure. So while it's an operation, not a whole lot, you can do to check for leaks on that until you get to variable to shut the chiller off all right. So let's talk to the process now, so you know you have a leak now. What do you do? Next, well, you know you have a leak.

We need to find that leak. So when you shut the chiller off the chiller sitting, idle more than likely is going to be below atmospheric there's a couple different ways. You can increase that pressure should bring above atmospheric and one of the more common ways is using a a water, a portable boiler or a hot water pack. Some people will call it it's basically just a setup, a rig like a handcart that has a little circulating pump on it with a couple electric water heaters, and you will hook that up to the system.

Y'All you'll show your valves off and under water piping. So you essentially create a closed loop just within the chiller itself and you'll hook, this hot pack up and circulate hot water, create hot water is circulated through the chiller and increased or refrigerant pressure above atmospheric check for leaks, and that's not necessarily my favorite way to Do it because it's very time consuming you could actually spend all day. You know six hours plus trying to get this thing up to to your three psi gauge in order to check for leaks. What I prefer to do is actually pull all of the refrigerants and it's not the most economical weather in the long run.

It's the best bang for your buck, because it gives you time to go through the chiller thoroughly and make sure you find every single leak that you could find. You pull all the refrigerant way it out. So you know exactly what you're dealing with in comparison to the main plate, charge and add nitrogen with trace. You know 134a.

Now we used to use our 22, but with the prices on it, you know our 134 is a lot more economical and will increase the pressures up to 10 psi very, very slowly, very carefully, we'll get it up to 10 psi because there is a safety on The low side, I called a rupture disc and usually those are set about 15 psi gauge to where they will burst, got it so, okay, so that's one big thing to consider is that you need to be really careful. You're, not you know jack, and this thing up to 200 psi: okay, like a difficult high pressure system, so you wan na really careful and gentle with it, because even though they're supposed to burst at 15, they could potentially burst lower than that. I would assume, if you hit them all at once, with with the pressure cranked yeah, usually before I add the nitrogen I'll put in maybe five pounds of 134a and I'll start slowly. Adding nitrogen I'll make sure I'll have multiple gauges on the machine of one.

On the high side of this is someone on the low side of the system. One on the low side is sufficient enough, but I like to doing something like that: Alec to overdo it and make sure I'm safe all the way around and I'll set. My nitrogen regulator for like maybe a hundred psi and just let it forward so the chiller and it may take two or three bottles, depending on the size of the children of nitrogen, just to get it up to that 10 psi once it hits about 8 psi I'll slow the flow down to about 50 psi outlet. I my my regulator and just kind of carefully watch my gauges and once I hit that 10 psi mark, then I'll shut it down and go through.

It certainly checking okay. So I imagine, when you're dealing with a unit of this size, first of all, there's gon na be a lot of refrigerant to recover. So that's gon na take a while, but then once you're getting something up to such low pressures. Doesn't that make it kind of difficult to find the leaks? I mean, I guess, I'm thinking like you know, sending something to 10 psi and finding leaks.

It just seems like that would be kind of tricky. It does, and I mean well, would you let me ask you: when you're working on a split system, you guys have a certain method right when you're really checking there's a certain technique that you go about it right, yeah first we'd do a little dance and then We hold our nose, I mean yeah sure I mean there's a typical position. I'd like to see a video of that cuz. I wan na compare notes to see if our dances are similar, uh-huh yeah, it's more of a dirge, more of a dirge yeah.

I mean there's there's a typical process, but that's that's yeah! That's what I'm wondering is like. It just seems like you're dealing with such a large piece of equipment at such low pressures that it's got to be a real pain in the very tedious. It's very time-consuming it to me. Leak checking is almost an art form.

It takes a lot of lot of practice to do it right. You know to make sure you don't miss anything. You got to go real slow and I will usually start at the highest point of the machine, because collecting refrigerant will usually fall to the bottom. You know at the floor level and so I'll start at the very top and kind of work.

My way down from there checking every gasket that I could think of every thread would connect and then there's some hidden areas that people kind of forgets, such as the motor terminal. Sometimes, though, I have to take the cover off of the box on that's connected to the motor and check inside, there make sure no, the motor terminals are leaking, there's other other little electrical boxes, mountain after their misters and different way or in connections and sensors. So you got ta, you got ta, make sure you hit every little nook and cranny and then, when you don't find anything that gets really frustrating and you have to think of the possibility of a of a tubes that are leaking refrigerant into the water system. And so then you got ta kind of go that route, which is a little more.

It's not very scientific approach, basically will just drain some water and into a bucket and stick our sniffer in there and see if we pick anything up just to get right in the water yeah, yes, fully submerged the whole thing right in the water and see what Happens and you never pick up anything ever again, cuz you ruined your leak tanker yeah. That's that's kind of frustrating too, because sometimes you'll pick something up and it could be chemical from the water treatment. You know so thanks. You got to kind of use your discretion.

You know, and before I go to the lengths of determining there's a leak in the tubes I'll go over the chiller at least three or four times just to make sure I didn't miss anything. And so how often have you found a chiller that is leaking in the tubes? It's a low-pressure chiller, maybe only only a handful of times, but those were cases where we kind of knew that something was wrong, that they could have possibly frozen up a tube or some other type of issues happened. Something got in the water piping and damaged the tubes internally, so it's actually pretty rare that you get a significant leak in the tube themselves. Unless you know there's some others outside force that that could have happened.

What would be a cause of one of the tubes freezing? Oh that's a topic for a whole nother, podcast, okay, sorry, well, improper recovery practices or charging practices. You can definitely freeze it to about a chiller. Sorry I'll leave that I'll leave that there then yeah. If, if you're not pulling the refrigerant outs in the proper manner or not adding refrigerant, you know and when you're breaking the vacuum and if you evacuated the chiller, then start and or forget you, if you don't do that properly, you could definitely fouseytube and really, if You start dumping liquid straight into a vacuum: ya, always half.

Whenever you're. You know you got your appears on your evacuated. You need to break the vacuum with vapor refrigerants until you bring the saturation temperature up above 32 degrees. I usually won't go to like 35 and then you can use the push/pull method to get all the liquid into it and you got to make sure you have water flowing technically, you don't have to have water flowing, but it's an added safety.

If you do it right and while it's not flowing, you should have new problems, but I was always like the you know messing around with stuff like that always like to play it safe and just get water flowing whenever I can and always introduce your liquid into The lowest part of the system that you can cuz, you don't want to go into a valve on top of the evaporator or the condenser just have liquid refrigerant, pulling down and flashing off, I'm hitting a tube or something like that. You know in a single spot. You're moving thousands of pounds of refrigerant, no constant in the same spot. The tube will definitely freeze it right and if it's a water system, then I mean - I guess at that point - you're more risk than if you had a glycol system or something yeah.

Well, especially on the condenser side. It's it's all water. I want the thinnest aside. There's no glycol, but I'm beyond the evaporator yeah.

You could have straight water. You could have glycol, but even with quite call I still I try to do as safe as I can. That way. I know you know at the end of the day when I'm going home, there's nothing that I could right done to cause any problems in that aspect.

Right and freezing a tube would be a pretty significant thing to cause, so you have to do the whole. You have to do the whole, like Tommy Boy thing, really like what you do. I think I would just get out of the car stream that there's bees everywhere and just go for that. Okey went for the other Tommy Boy incident.

Okay, good, make sense! You learned everything I know about business. I learned from Tommy Boy, hey, it was pretty successful yeah. So it's not that's true, that's true, alright! So and then I guess, I guess one way that I'm probably thinking about this wrong is that if you have, I guess, I'm thinking in terms of an a high-pressure system when you have a leak, it's leaking under high pressure normally, whereas when you have a leak And a low pressure system, it's leaking under low pressure, so it's not gon na take as much pressure to even do leak detection, because if it's leaking under low pressure, you're gon na be able to find it easier under low pressure. Does that make sense? Yeah I've? Actually had cases even on a high pressure chiller, where we would hook up the vacuum pump to it and we would pull it down.

We just couldn't pull down the Micron's on it, just it would not pull down and then we would put like 50 psi. You know bumping up to 50 psi, they check it and we could not find a single thing and just by chance that happened to be where we were purging, the nitrogen in the trace gas out of the chiller, and we got down to like 5 psi and We ended up finding the leak at 5 psi and it was on a on the suction, oh boy, there's a butterfly valve on the bottom of the suction, oh, but what was happening was with the higher pressure was actually sealing, causing a seal on the gasket. With the higher pressure, but when we dropped it down to 5 psi with lower pressure, the leak actually showed up and exposed itself under under low pressure doesn't have enough pressure behind the gasket seal itself. Right yeah, I mean and you'll see that in some cases like some things that will leak under vacuum won't leak under pressure and some things that leak under pressure won't leak under vacuum.

Because of you know, Jason should get patches. You know that a little patch of corrosion or something will cover - and we see that in typical air conditioning - it's it's rare but usually it'll still be leaking. It's just the rate changes, but we've seen some. That's like you know, for a fact: it was holding under pressure and then you put a vacuum on it and then it starts having an issue or vice versa.

So and again it's rare, but you do see it on occasion. Oh yeah, absolutely, no, all right! So any other top tips. It sounds like the main thing when you're working on chillers this stuff just takes a lot of time. It is very time consuming make sure you have good equipment, good, live detector equipment, actually yeah.

That's what I would ask you. What do you use yeah? I had a infocon detects a lot, but I actually just purchased a H. 10 Pro through your partner. Textured tool did use the offer code get schooled, I used they had it on sale and I used the offer code and I did the easy financing.

It was pretty awesome their work. That's like a trifecta, that's like a quad factor of awesome right. There yeah - and I was very pleased with it - and I've used it a few times already and it's worked out very well for me. Just got ta watch the battery yeah watch.

You know I was actually surprised. It only takes like three to four hours for it to charge up it's where my DTEC I'd have to almost plug it in overnight to get a full charge on it. Yeah I haven't used the latest version of the HM Pro, so maybe it's because I would let them like fully discharged and then just sit for long periods of time. I don't know if that might have been some of it, but I have the only issue that I've ever had with them is the battery the battery life.

You know how long the batteries last so cool yeah last couple days that I had the jb Prowler and I liked that one because it used alkaline, they use doublea's. So it was. I got batteries low, just swap new batteries and you're ready to go. It was those nice little feature yeah.

I actually in some ways. I almost wished that that's how it was, but I guess for some of these that would that would go pretty quickly. Have you ever used the PG Mir the high super high end backer hey? Is that English, I don't know no PG Mir, you don't know what it is. I know I did not really that's the I don't know if you saw the video that I did its backer acts like highest and the portable big detector.

It's like the technology. They use in their stationary leak detection equipment, but you can feel it will actually detect every refrigerant down to one part per million. Okay yep - I just didn't - know it by the name, but I did see that was pretty cool yeah. It's pretty neat, so you need to get your employer to buy you one of those.

Well, I will okay, I tell them that I said so. I'm sure that'll carry a lot of weight yeah. You know Brian or says that I need a PGM IR and going back the first time that we had spoken. You had asked me, but what is the one of the things that I run into the most or I hate the most in leaks, refrigerant leaks or air leaks and chillers got to be my number one Bugaboo that really drives me nuts, because it's just such a Time-Consuming process, finally to fix the leak.

Actually, we have a service local here in the Detroit area. There, a refrigerant recovery service will actually utilize them to come out and pull all of the refrigerant out of the machine. While we're you know I'll, be off on another job, doing something else and they're doing that for us, so it actually saves us some lot of time. So once the refrigerants out, we show up and we can start doing what we got to do to it and when we're done, we just put the refrigerant back in ourselves, call them up and pick up their tanks and it's it's worked out very well for us.

It's it's been a nice little setup. Yeah we've seen services like that Walmart uses them sometimes we're starting to do some more. It's more wally world work and it's not arresting interesting and in those cases and on refrigeration, we'll just take one rack and pump it into another rack, because you have these gigantic receivers that are, you know, designed to hold that much excess refrigerant. One thing I wanted to ask you is that, because you know in a centrifugal system, the lubrication system is separate, I'm correct in saying that right it has its own dedicated lubrication system, but it does mix with the refrigerants it's kind of hard to describe.

But in a sense yeah it does have its own lubrication system that our oil is not designed to flow with the refrigerant into the chiller itself. And you know the oil pump pumps to the bearings and the seals and has a dedicated drain back to the oil sump. So so a my question, then, is you know in leak detection, typical systems, we're always looking for oil? Does that become like a non-factor than where you don't see oil? Oh, no, actually, uh, I'm the low pressure chillers, depending on where the leak is. If it's on the highest idea you, you will see some oil in certain cases, but on high pressure machines.

No oil is a huge red flag. You know we see oil somewhere, we're like all right where's this coming from. What's going on here, so I mean when I first have brought the killer. That's actually one of my first things I do before I break any tools out.

Is I'm starting to look around for oil to see any any signs of it so on New York killers they use a open drive motor, so the motor is not inside the refrigeration circuits. An open drive motor has grease ball bearings just like a pump motor or something like that, and it's a flexible coupling that connects to the shaft of the compressor and the shaft on that compressor is a is a mechanical seal and sometimes those seals fail, but they Will actually also drain a little bit of oil as the chillers running, there's an actual there's, a positive oil pressure depressingly against that seal about create to seal as a result of that, some oil will leak out of that. But there's a little collection bottle that sits under there and there's an acceptable amount of oil that you're allowed to see within a certain amount of time. I think it's like 70 milliliters within 14 days.

If it exceeds that leak rate, then there's a no either of those. The seal is worn or there's a mantle ring or gasket or something in there. So yeah, no oil or oil is a definite telltale sign. But when you don't see the oil, it's kind of bums me out cuz and I'm like oh man, I actually got ta, try and find this secret stash.

Yeah, there's nothing obvious. So yeah working is a real drag. You know it. Bums me out is.

I got rather just sit in my van listen to the rain and be on podcasts all day yeah a way. That is what I do it was. I was actually gon na. I had to postpone this cuz.

It was storming pretty out here, but I luckily it what up so it worked out. Good yeah sounds good, so yeah just to clarify, obviously on the low side of a low-pressure chiller you're not gon na have all because stuff, because atmosphere is going into the system. Nothing's coming out so obviously you're, not gon na see oil in those cases, but I was just coming to bring to it in a larger sense yeah unless it's on the oil circuit itself, because there's external oil lines out of the oil sump from the pump that Go to various areas on the compressor and those are on a positive pressure on the oil pump. So if there's a leak in that area, you will definitely see oil, but that doesn't happen very often got it.

Cool makes sense and in yeah so essentially the you can either do the using heat to drive the pressures up or you have to pull the whole charge pressurize use another refrigerant and with the nitrogen and leak to take that way, and then evacuate it back down And recharge once you have repaired, which either one of those is. It sounds like a pretty massive undertaking, but that's the nature of low pressure. Chiller leak detection, I guess yeah that'll. Take I mean we can spend all day and looking for leaks and not find anything, and you know there's leaks, you can see your temperatures readings.

Your approach levels are rising. You know your perch timer is increasing, so you know there's a leak somewhere around the high-pressure machines you just you could just tell you're low on refrigerant, because the things running dry. That compressor is just screaming, then wheel. That, with all your other readings, your garrison is low when you do figure out where it's at, but the nice thing about that is you don't have to shut the Machine down.

You can certainly checking it right away. You know the oh, I'm the low-pressure machines they're a little more time consuming good deal. Well, I appreciate it. I appreciate it sir.

This has worked well and - and hopefully I will get a chance to have that level of fun at some point - be able to go I'll, eat detection on a on a low pressure machine and when it happens, you'll be the first to know yeah if you're ever Up in the Detroit area, let me know you can use the extra help yeah yeah I can bring. I can bring my P G Mir, then I got from true tech tools using the africo get schooled. Absolutely I'm always looking for a free, labor all right man. Thank you so much.

Okay, thank you for listening to the podcast. Thank you for listening. All the way to the end shows a level of dedication. You just keep letting it play when you know that I'm not gon na say another useful thing for the rest of this podcast.

But you know, I appreciate your your commitment or your insanity or the fact that you're just zoned out and not even paying attention - or maybe you fell asleep - maybe you're just still playing and you're just nuzen away, and in that case I might wanted to sing you A little lullaby thank y'all, okay, I think I'll skip it. So thanks for listening, like I just mentioned, but one thing that I'm gon na ask you: if you listen to this on YouTube or if you listen to it on Facebook or if you listening to it on the on the website. Even if you listen to it on HBC our school comm, thank you for that. But the best place to listen to the podcast is in the podcast app.

If you have an iPhone and the podcast app is a purple little radio tower. That's what it looks like at least it's not actually a purple radio tower assistant app. That looks like one on your iPhone. If you have an Android device in you're, gon na have to go to the Google Play, Store and you're gon na have to download an app and that app that I would suggest downloading is called the stitcher app and you can listen to the hvac school podcast.

There - and all you got to do is just use, search, search, HVAC, you don't even have to type in school, just search for HVAC and you'll, find the hvac school podcast right there and then subscribe to it, and then that way, all you do is just go Back to your app when you're ready to listen and we'll be right there, every new episode will come right there on your phone and you can listen to it anytime, you're ready, and that is the easiest and best way to listen to a podcast. You can plug it into your to your stereo in your car home stereos. I'm not sure I guess they go home stereos. I don't know what they would call now an mp3 player.

I don't know what they call that stuff anyway, but in your car there's a way you can listen to stuff, and so I would say you can plug in there. You can connect to your Bluetooth if you're, that fancy or you can use headphones for that matter. If you can, if you'd, rather, if you're a noisy motor room, like my friend Jeremy Smith, often is you can listen that way, but another thing I want to mention to you is that. Finally, I already already mentioned this once in the bud gasps.

Let me go ahead, mention again and that's test. Oh 60th anniversary there fall combustion, analyzer promotion. It really is a great promotion, because if you double up, you can actually buy from true tech tools. Usually offer code get school.

Get a percent off then go to HVAC. Our school comm forward slash, fall promo and you can then either get a 7:45 non-contact voltage sensor. If you get the 310 or if you get the 320 or 330 series combustion analyzers, you can get yourself a brand spankin new testo 770 3, which is the meter that I have in my bag, and it is a great meter. Some people have some issues with it out there in radioland, but not me I like it.

I think it's great and so testo is celebrating their 60th anniversary, and one thing I want to say about test: oh, is that test. Oh has been the most consistent sponsor that we've had they're the ones who have Mak us through thick and thin, and I really like tests. Oh and I really like what they're doing and they've got some great new things coming up like I've mentioned in the previous episode, the one right before this, or when I say I mentioned it, it's actually Jim Bergman who mentioned it. The test is going to be working with the measure, quick, app and they're one of the first ones to sign on to do that, and that just tells you something about test out that they are they're, confident in the product that they make enough.

That they're happy to to share their data with an open source product like measure quick and I sure, as heck like them for it, because I think it's the right move and I think testers doing a lot of the right things and they're gon na keep coming Out with great products or some some secret projects and the works that I can't tell you about, but I know you're gon na like so. If you haven't tried testing yet you're gon na find that it is a great product at a great price and the fall promo is a great way for you to get a great combustion analyzer and I'm going to keep just saying the word great. All until the end of this part caste, but that is HVC our school comm forward - slash fall promo to find out more about the test. Oh 60th anniversary best-in-class fall combustion, analyzer promotion.

Now one other thing just too for those of you who are still listening. You are very really for bearing with me because this was an especially long outro, but Jim Bergman mentioned that my super stupid dad joke the other day, actually kept him listening all the way to the end cuz. He was anticipating it, my joke about the chicken crossing the road, and so I've decided that from now on, in every podcast, at least every one that I remember to do this everyone that any podcast is worth its salt, I'm going to tell a stupid dad joke At the end, because I think there's something about technicians, something about being in this industry. That makes you appreciate a good dad joke and you can put this one in your pocket and you walk in the door.

You can tell it to your wife or to your kids, or you can text it to one of your adult children if you like, but this one is something that I say whenever I go through the this is a checkout line and I'm when I've gone to The grocery store - and I have milk, which I often do this - is actually true story. I often pick up milk on the way home, so those of you who don't know I have nine kids and so I'm over always churning. I don't know, even though we have two refrigerators, and so, if the, if the cashier says to me, which is like an in a bag, I just respond now you can leave it in the carton. Thanks for listening, HBC school, we'll see you next time, you.

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