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That's their Viper cleaners, especially the Viper spray. Can, if you haven't, tried that for a coil cleaning in place, then I'm gon na suggest that you give it a shot. It really is very nice and then also that all their cleaners for cleaning condensers their pan and drain spray is excellent check it all out by going to refridge tech comm, or am I going to true tech tools comm, you can find it all there as well Seriously his initials RB, o or reason Brian or yo bruh, thanks for listening to the hvac school podcast, the podcast that helps you remember some things that you forgot along the way as well as helps you remember some things you forgot to know in the first place. I'm Brian, this is a little podcast that we just cracked the 1.5 million listens mark thanks to people like you who tuned in to this.

I really do appreciate it. I appreciate you telling your friends and sharing about it on social media means a lot. So many of you have said so many nice things. Some of you have said some mean things and that's okay.

It helps balance the yin and yang the dark side of the force. So if you got something mean to say, don't hold it in that's what my mother used to always say, but she was a Sith Lord all right. So today, on the podcast I am talking to John Oaks. John, is a technician in Utah, really good technician.

Guy who I've interacted with online the resident mammalogists at HVAC school, but also just a good, solid dude, it's one of the admins on the Facebook group. If you haven't joined that yet you can interact with John there, but today we're talking about vrf and kind of a real-world look at what John knows about vrf and what he runs into every day. So here we go John Oaks talking to vrf, ok, so just to set the scene here, there's some podcasts that I do where I'm at my office studio and they're set up with luminaries of the HVAC industry and then there's some that I do because I'm trying To fight a technician into coming on, and I don't know that I've fought with anyone longer than you to try to get you on the podcast, I literally have guests in my house. You know Corbett Lunsford by any chance.

Have you bumped into him online at all? Probably the name doesn't ring your bell, but I'm sure his profile picture I'd recognize him better with faces than names. Yeah he's a friend of mine. He has a tiny house and it's parked in front of my house right now, and I scheduled this with you, knowing that he would be here and knowing that I would have to walk away from visiting with my friend, because I did not want to miss out On making that I got this done so the whole point of all of this woody banter. If that's what this is is just to let you know that this is a priority for me and it better be good.

I've been told that I'm good at putting people at their ease, how's that working for you hey. I have some expectations now, so that's always good. Whenever it's your first time and something to have a lot of expectations, I learned that, on my honeymoon works out really well today, we're talking about vrf we're talking about variable, refrigerant flow systems, where, if your Dyken vrv, because you just got to be a little different Well, they were first, actually, I think everybody else glommed onto the vrf thing after they already set the tone. They were first they're still different, though, but that's okay, you're saying literally Dyken.

Vrv systems are significantly different than other vrf systems, you're just saying they're, the only ones that call it vrv; no, they just copyrighted that name, so they have it, but they invented vrf for vrv back in and I think 82. It just hasn't really been on this side of the world in our market till just recently, last decade or two 82 was a good year. 82 was a good year for several things you born in 82. I was a good year plus a good music Madonna was in her prime at that point in time and be careful Brian, you don't want to date yourself here.

I wouldn't want to date myself what enough about at the vrv history. I have a list of questions here and we're gon na work through them. Okay, you ready. Let's go first off, I'm gon na.

Ask you this question, which is what the heck do you do day in and day out, because I know you do a lot of vrf, but what does that look like? So I am on the service end of things typically with vrf you're gon na have people that install it, which is gon na, be setting outdoor units piping well for Mitsubishi, it's pipe in between the indoor unit, which would be the branch controller and the outdoor units And then running line sets Tolley indoor heads you also gon na have control guys that are run in the daisy chain, setting up central controllers programming, the individual units doing start-up, calculating the total charge for the system and then once they're done. They all walk away and move on to another job, and then we have this building sooner or later, things start to go sideways and that's when service gets involved and find the leaks recharge. The units change the filters watch, the coils then troubleshoot any issues that come along with the systems, and so I'm on that end of things, I'm actually probably really bad at the install in, but as far as troubleshooting, these systems are pretty complicated or they can be Think that's kind of the part of the industry that I've gotten myself into alright. So let's do some quick definitions.

Well, I'm not gon na waste a lot of time explaining what vrf is because you're listening to a podcast, that's about vrf, so you must know something about it, but essentially the way that I like to explain it quickly is if you've ever seen, ductless or mini Splits, it's basically like using that type of system, but in a larger commercial environment where you have multiple combinations of air handlers or heads. But you mentioned a couple things that I want to nail down. One of them is a branch box. So, for somebody who isn't familiar with what a branch box is, how do you explain that each brand is gon na? Do that a little different again, my specialties Mitsubishi, and so basically, you have a compressor or compressors running outside, obviously compressors polling instructions putting on discharge and depending on the mode that it's in whether it's in heating mode or cooling mode or some combination of both the Branch box is going to be taking that and directing it so units in each heat it's gon na be directing discharge gas to them.

It's gon na be getting liquid back from those units that need cooling their zones that need cooling. It's going to be sending liquid down to them, pulling suction gas back, it's got some sub coolers in it, and basically, what those are doing is any liquid. That's coming from the outdoor unit, it's some cooling mode, sending liquid from outside. It's gon na sub cool that liquid through these and it's gon na just try and maintain the pressures, and it's got a lot of valves in there a lot of Scylla noids.

It's got several led's and it's basically just directing traffic between all the indoor zones and so in Mitsubishi. The branch box is what allows it to simultaneously heat and cool, and so they actually have a more basic form that doesn't have a branch box or brandy controller. I called Y series very similar outdoor unit and you can same thing connect a bunch of indoor units they just all have to be in the same mode hall and cooling all in heating, all the ones that are calling anyways. So the branch controller is basically just a lot of copper piping in valves yeah and when you mentioned that every manufacturer does it differently.

This is one area that is done differently, depending on the manufacturer, but often in ductless we're used to having the metering devices being in the outside unit by the compressors. Traditionally, all the condensing unit we're used to having our electronic expansion valves out there, even in multi ductless in many cases, maybe in all cases I'm not a hundred percent sure. But in many cases at least, the metering devices are actually either in the branch box or in the air handler fan coil in a wall-mounted unit itself, and I don't actually know in Mitsubishi - is the metering device in the branch box or is it still in the Air handler, if you were in heating mode you discharged gas from outside, go through the units you get liquid back around through the sub coolers, get heavily sub cooled liquid, there's a metering device in the branch controller. It's going to flash that to saturated suction gas.

Send that outside run it through the evaporator outside then back to the compressor and again this is one that every manufacturer does way different, because Mitsubishi is a two pipe system where in some modes one of their lines is discharge, gas and some of their modes. It's going to be a liquid, and so we'll probably talk about that more later. But now in cooling mode, the metering device is just going to be all the indoor heads that are cooling, and so it's just going to take that suction gas and just run it straight to the compressor outside and then that mode the outdoor coil is going to Be a condenser in either way with vrf systems, you're, not metering it at the outside unit you're, either metering it depending on mode at the branch box or at the head, and I think there are some that even in cooling mode will actually do the metering within The branch box - I can't be a hundred percent sure again, I've been through training on a lot of these things, but I've only worked on a handful of them, but one thing that I think does differentiate ductless from vrf is that in general, when we say vrf We're talking about commercial applications and generally three-phase, although I do understand that Mitsubishi has a category a single-phase, what they call single-phase vrf and I don't know what the difference is between that and typical ductless. Or are you aware, it's interesting the lines between commercial and residential start to blur in this, because in theory, you could take a commercial unit like the ones you talked about, that would run on a lower power supply and if you fed them, you could easily run A house on it I mean they make these condensers that are like a 6-ton condenser.

You could run the house on no problem, but what I deal with is typically on the commercial end. I haven't dealt a lot with the ones that are designed for residential. I know that a lot of the manufacturers have mini-split design with multiple lines, which is more like that y series. I had talked about whether they call them like multi splits.

We've got like couple of port connections at the condensing. You know to the outdoor unit. We're not gon na spend too much time focusing on that. I think there's gon na be a much larger majority of tax who will have worked with ductless, so I'm kind of trying to give them a vision of what this looks like.

But the next thing so there's the branch box it's sort of in between the air handler fan, coil head or whatever you want to call it and the outside unit where the compressors are located the branch box in between. But then you mentioned daisy, chaining controls and that's something that I think a lot of techs who mostly work on residential, aren't gon na be familiar with. So what does that mean on a traditional system? It's gon na be driven with a 24 volt kind of signal. A lot of the newer modulating systems have proprietary communicating controls for most of the vrf you're more in that direction, where they have controllers that will work with them.

It's not like 24 volts. It's like 20 volts DC that are like communicating, because there's more than just run heat run cool, that's being communicated, there's all the temperatures from all the sensors, the mode that it's in the fan, speed when it goes into defrost. You've got to send the signal out to up to 50 units to say, hey change, mode change. What you're doing the whole system is more interconnected, and so the controls are a lot more advanced.

Other commercial pipe systems might have a more basic control like a lot of rooftops could be run on a residential type thermostat. But then you can have a BMS system that can take over that and run it where a lot of the vrf has like an onboard communication that could be standalone where it could run everything if you just put the thermostats in that the manufacturer has yeah. So what I was wanting to kind of nail down is that when we think about in the more residential world, even when we're thinking about communicating controls, we're more thinking, one two one, two one air handler: condenser thermostat air controller in this case, you're taking multiple components And you're taking control, comm, wire and you're, just basically connecting them all together and then you're programming it at the controller, with the difference, whatever the addresses are for the different years, essentially addressing all the different units in programming and in essence, in most cases, you're really Literally, just looping a comm we're interconnecting everything. Essentially I mean and not everything everything, but a lot of different components are being connected in together and then you're essentially sorting them out when you address them in the control, at least that's my way of understanding.

It tell me if I'm wrong there yeah so every unit, the outdoor units, the branch controller, all the indoor units will have an ADD and they've got. Rules of this headdress has to be in sequence with these addresses, and this type of unit goes in. This address range and they've got rules like that, but they're, all daisy chained together they're all fully communicating if they lost a unit that they know they're supposed to be saying. They'll other units will report that error.

Haywood communication error, I'm like if the outdoor unit has an issue. I throws a hard error code and shuts down all the indoor. Thermostats will start flashing, that error code, it's all very interconnected, which is both helpful and not helpful as well. I remember there was one that had a condensate issue and because the condensate lines can be tied together, it said.

Well, I don't know if I'm flooded in the building shut the whole floor down because it had a pump that wasn't disconnected so can be a benefit as a bane, but more and more as time goes on. I'm seeing systems where you have a commercial system of medicine or an Allerton or a safer kind of system that is going to be pulling data points from the indoor units through that communication protocol and also can be writing to those points where they say. Okay, put this one in an occupied cave, but this one, the heat, Kait change, this one set point. So when I started working on these, I didn't see that as much and I'm seeing it more and more as time goes on, which again can be good and bad.

We had one the other day where the schedule was set up wrong, and so it took Thanksgiving a day. Early, the whole building was unoccupied and nothing was a temperature right. I mean that's the same with any type of control strategy that we use the more complicated you get the more you're trying to do, fancy setbacks or trying to make adjustments based on preemptively, you're gon na run into more potential for error, and so you just have To be that much more diligent to make sure that it's all set up properly, it makes sense that those sorts of mistakes will happen if you're not super diligent on the setup, it's more than just making sure everything's running in the right mode. So, like the outdoor unit, kind of will flip through the different modes heating, only cooling, only heating, main cooling main depending on what the indoor units are calling and so to coordinate that what should the vows be doing? What should the compressor be doing doesn't need to ramp up, doesn't need to ramp down? Was it have enough cooling units shut down that we need to switch to a heating main mode to coordinate that as a lot of information that needs to be collected and gathered, and I don't know how you'd do if anything, but a fully communicating system? We talked about this coming out in 82.

I imagine the systems we have now are a lot more advanced and they were in 82. The manufacturers, as time goes on we're seeing as more and more technologies become more mainstream. I just see these keep getting better and better what they can do compared I've run into a couple buildings that had systems from 10-15 years ago and I'm floor with how much more sophisticated the new ones are coming out now in just even that short amount of Time this industry is not like okay, this is it. This is the product.

This is vrf, they are constantly improving, upgrading they just getting better and better and a lot of people. You start to see the advantages of this type of system, give it 20 years. I'd say probably one in four buildings is gon na be BRF some brand. Some variety of it I mean now is a really good time to start learning about these companies should probably already be bidding on these if their commercial contractor, but getting your mind open to the possibility of working on these and upping your game to understand.

Okay. So it's a heat pump. What's a heat pump, okay, what runs on an inverter? Okay? What's an inverter? How does that operate kay? It's got these controls, there's a lot of components that need to be understood like you can take a basic understanding. Well, I understand the four components of the refrigeration cycle: okay.

Well, we take that and we twist it like a pretzel. These actually run like a high-pressure zone, but they also have a mid pressure zone when they're gon na have your basic components, but it's we've got systems we're in the right mode. If you've got units that are heating and some that are cooling, you mean you might not have refrigerant going through the outdoor coil at all, all the heat transfer may be from this zone here to that zone there, and then the suction gas go back to the Compressor very different from what you would see in a standard: commercial rooftop, a standard, commercial condenser residential systems. I mean even some of the more advanced systems like some of the geothermal systems.

I mean the complexity of these is starting to approach for the comfort, cooling and he's starting to see more components that are like you can see in a rack grocery store. But it's a good time to be learning about these and to be getting out there. It really is a wonderful opportunity to expand yourself as a technician and give yourself a place in the industry in the next 20 years. You pulled a Jim Bergman on me just there.

What saying in the next 20 years, do you know what a Jim Bergman is? What's a Jim Berger, not Jim Berger, Jim Bergman, you know, Jim Bergman is right felt like a cheese and all its Limburger. I know Jim Bergman is yes, I know well, Jim Bergman is when you start off on a technical subject, and then you end up spinning into like this really in-depth, like positive industry-wide motivational speech, so that was good, I'm very motivated. I want to go work on a V RF system right this. Second, I want to go find one right now and go work on it.

Do they have capacitors, because I know how to change capacitors, I'm really good at that. So, like the inverter boards, I could try to count up how much capacitance was on one of those. It was like twenty-five thousand microfarads between all the capacitors on the inverter board. Well, that's way too many micro, farad's and they're all excited to the board.

Wow. That's a lot of them. Some of the indoor units, some of the indoor blowers, are running on inverter boards, no more PSC motors, which is actually kind of trippy, because you can't even tell when they're running. What do you mean? You can't tell them they're running because they run so slow.

I've been sitting there waiting for one to kick on and then I'm like. Is it even running, and then I reach out my hand. I can feel just a little bit of airflow coming out on like a kick on when how long is it up and going on where you know when a PSC motor kicks on, you can hear it down the hall yeah. Well then, that's sort of like ECM motors that we for common residential for awhile, I mean that's, basically, what an ECM motor is.

It's just a inverter drive or a VFD coupled to a three-phase motor, basically right anyway. I digress next question that I want to ask: you is one of the first things whenever you have a new technology and we've seen this a lot with flare fittings. That's one thing that we saw in ductless and I'm sure that's carried over to vrf is just if people didn't know how to make proper flares now became a nightmare for those of us going back later. Trying to deal with, especially these systems that have total charges is significant and when you have a V RF system, you've got a lot of refrigerant.

That's shared across many different heads and leaks can cause a real problems. So what are some of the most common installation errors that you've run into and you've had to correct as you've done more and more of this well charge on? These is pretty critical because it's not as simple as well and block the outdoor coil. Kick it on and check your sub cooling. If there's a charge issue the problem that these systems have is they're too smart like if it's low on charge, it just slows the compressor down and the pressures look normal it just it's moving less refrigerant, but the pressure comes up and head pressure comes down and It can mask of those problems really well, so how do you deal with it like you're, not weighing out total system charges? If you have a system, that's got the leak in and they're a little bit short on charge.

How do you deal with that? So each manufactures a little different. I know Dyken has like a charge mode where it will tell you add gas take cast out and it will take the guesswork out of it, which would be nice. I wish Mitch would be. She had that from Mitsubishi.

They've got a couple options, obviously the most accurate is they have what's called the diamond system builder, where you punch in I'm you're like I've got these upper units. I've got a branch controller, but these indoor units that are these models. I've got this many feet of line set. It's this size and you punch in all the information it says k your total charge for the system is 162 pounds.

You need to add 112 pounds or whatever and it's there and it creates a record. It's permanent. You save the file and if you ever have a question on the road I mean you'd hope it'd be written on the unit. But even if it's not let's get filed with Mitsubishi, you can hunt it down said: hey here's my charge.

So if there were ever a question or if the system were empty, you know how to massively core you needed to change compressors and you had to pull it all out. You can compare that and weigh that amount in now. That's some practical! If it's in the middle of the summer, you just want to check, and so they've got a mode called refrigerator just mode, you kick it in the mode put everything in test cooling mode. It stops modulating as much goes in a more stable mode.

Compressor frequency kind of doesn't fluctuate as much the indoor metering device to stop opening and closing so much they don't hunt as much and then once it's all stabilized you just look and say: okay, my compressor discharge should be above this below this. My sub cooling and the branch controller here should be above this below this, and here should be above this, and if everything checks, the system is roughly charged correctly. The really hard time to charge them is the middle of the winter, because you can't do most of those, and so you can always charge it till the numbers look decent, but you usually want to go back and charge when you have better conditions, you pull the Whole charge or go through the refrigerator just mode, getting the correct amount of charge in there is critical, like I've run into some systems. Where I don't know exactly what happened, I think people round it up on line set lengths.

They used a 75-foot line set, but they cut off 15 feet, but they listed it as 75, so they listed too much line set, told them too much charge. They charged it to that amount and then that's too much. It's with anything. If you put garbage into the calculator you're gon na get garbage out, so the people that are installing these there's a great deal of care that needs to be taken while you're installing them planning that goes into it.

Accurate notes, accurate red lines. It doesn't react well to being installed poorly I'll put it. That way I mean if there are leaks and you lose charge again, you have run into the issue charging it correctly. After that, have you run into a lot of challenges with leaks after installs, so for a time Mitsubishi was using flares, and I personally like flares, I know there's some people that love them some people that hate on my liked them if they're done right, but I've Had to fix a lot of layers that were leaking, you go look at the branch controller because you got 32 flares up there.

You can look spot the oil pull the line down redo the flare done that a lot. I've probably fixed 50 60 flares. At this point, anymore, they're, all the new systems coming out are. The majority of the connections are braised now, but the double-edged sword with that is it's not as easy to create a braze joint, that's gon na leak.

But if, for example, if you don't flow nitrogen, while you brace these systems are different from any system, I worked on because I mean there's screens throughout the system, little wire mesh screens inside the different points, but there's no filter dryers like that stuff. Just just gon na keep circulating around until it finds something to plug up whether it's a pickup screen or a screen out to an LED or something like that, and so again they don't respond well to being poorly installed. It might not be in the first day week month, but you give it long enough and you'll plug something up: you'll lose oil return and then you'll be changing. Compressors yeah.

The other side is, is that with braze connections and I'm a fan of braze connections, but the challenge in commercial is now you're gon na have so many braze connections and if you have a leak on one and you go back later well now, you've got to Bring your torches into a commercial building and that can cause a lot of heartache, bringing torches in and making a fire inside of a commercial building and there's a lot of restrictions that are involved there. That are fun to deal with. So as much as I prefer. Brazing and do kind of wish that we would just get better at making flared connections because it does eliminate some of those problems.

Well and the majority of the repairs I make. I mean other than maybe adjusting charge and tightening of flare, which is rare anymore, because a lot of connections are braised and the vast majority of repairs I make on one of these is going to be in the refrigerant circuit somewhere and it's gon na be brazing And so, if this is something you want to get into, I mean your brazing skills need to be spot-on because there's a lot of sensitive components that they have in here I mean they've, got transducers they've got LEDs, they've got solenoid valves, they've got everything from ancient 5/8 lines all the way down to like eight inch line capillary tubes. I've had done my game when it comes to brazing with this, but it's good it's something that I feel someone could very easily specialize in and get very good at over time. But how do you well that's what you've done right? Well, I'm working on it every time I think I've got this stuff figured out, something else comes out and we got something that kicks your butt and you got ta up your game again.

So at one point I would have said yeah, I'm great at this now, I'm just like I'm doing. Okay, I'm doing okay and I think that's something that's kept a lot of people away from it is when you start looking at it. I mean there's a learning curve, there's a steep learning curve right up front, even just to look at the system to pull those data points because, like I was talking about earlier, the control system can pull those data points. Small, the indoor units from all the outdoor sensors figure out what it's going to do command valves.

You can pull that, but you need a laptop to do it. Then you need to have a special software and a special interface tool, and even if you have all that from intubation at least it's just a wall of data coming at you, I know some of the other brands have more user-friendly interfaces where it's got a compressor And it shows that it's running and it takes the data points and overlays them for different spots from Mitsubishi. It's just bunch of data. It's like Kay, thermistor 14 has this temperature and you just kind of need to know where everything's at, and so it's taken some time to get comfortable.

It's just looking at a wall of data and looking at trends, trying to figure out why it's doing what it's doing and what may be wrong with it. I want to take a quick pause here and thank one of our sponsors and talk a little bit their product that is filled, peace and the product is the M r45 recovering machine. I've used a lot of recovery machines over the years. I know that they can be a giant pain in the butt, but the M R 45 just makes it so easy.

In fact that was a complaint that one of my installers had is. He said I don't know how I feel about this tool, I'm like really what don't you like about it he's like. It makes it so easy that when I train a guy using the M r45 and he goes and tries to use a different recovery machine, he doesn't know what to do. So.

I guess that is a risky run. Is that once you use the M R 45 you're not going to know how to use anything else, because the things are so intuitive? But it's got a nice digital display on it? You don't even have to use gauges. You can just hook it straight up with a hose because it's got the valves on it, and then it's also got a pressure gauge on the recovery machine, making it very easy in addition to the digital display. It also has a DC motor in it and it's very quiet.

It's very light, there's a lot of really good traits. You can actually find a video that I did with my technician, Bert at true tech tools, YouTube channel on the mr 45, and you can also buy the mr 45 at trusted. Supply houses all around the country or if you can't find one go to true tech tools, com look up the mr 45 and use the offer code get schooled for a great discount all right. Here we go back to John.

What were you gon na? Ask me before you were like how do you and then you stopped how we gon na ask you because there's a third option with between flares and braces, and that would be with a zoom walk. I know some people absolutely love it. It's the best thing ever and other people ya know, maybe later or never. I was just curious how you feel about that.

I think it's something that I think it's coming. I tend not to be an early adopter and things that have really high risk. I think there's certain applications that it's worth looking into, I mean, as you and others know, Zoom lock was once a sponsor of the podcast and I am not opposed to it. I think it's a good technology.

I think they did a good job with it, but the challenge is: is that there's been mistakes made and so there's some very large retailers of which I will not name who are customers of ours who strictly ban it? Because there's been issues - and I think the issues are largely due to installation practices - I don't doubt that, but like anything, if you're gon na do something that's very high risk, you got to get it right and I think manufacturers who bring products to market need to Be more hands-on to make sure that it is right when the risk is high, as I think it's coming, I think the day will come where the majority of the connections that are the industry will be flame free, there's reasons why you don't want to pull the Flame out all the time, there will always be the need to use a flame, they're, doing repairs and things you're gon na need to know how to braise that's necessary. But I do see a future at some point where we're gon na make connections that are fairly easy to make using specialized tools that aren't going to involve either making flares or having to pull out your torches in order to make initial installed connections. But again it still comes down to how you actually apply it. Do you do it the way that it's supposed to be done, otherwise, it's gon na leak, that's just always gon na be the case.

So what are your thoughts? I think that'd be great as much as I enjoy brazing I've had brazing, you can get burn. You can cause issues with the piping you're sitting there catching an insulation on fire like this, so no I that would be fun. That would be nice to have that. Come down the pike, but with all those that we just talked about flares and brazing and zoom wok mechanical fittings like that, if they're installed in properly any of them there's problems that they create, so whatever you're doing make sure you're doing it correctly make sure you Have a tight dry system because here's the thing we talk about the problems, but I have systems that they were installed properly.

The charges, correct and all the joints were put in correctly and other than looking at it and washing the outdoor coils and changing filters. I have a zero repairs on them going on like five six seven eight years, I'm sure something will break sooner or later, but you just kind of look at it like yeah. Just doing this thing, no issues, it's just doing everything. That's supposed to tell temperature constantly zero issues when things are installed like that yeah I mean you'd wish every system every building was installed.

That way I mean, if every system that installed that way, I don't have a job but - and that goes back to the old like even if all else fails. We have a job because we're the janitors who have to take the stuff apart and clean it every once in a while. So we're always gon na have a job. Well, there's no capacitors change, Brian, so yeah! That is true, and it's true.

I that's all. I ever do is I just I open up an air conditioner and I just look for the failed capacitor and if it doesn't have one of those, then I just put it back together and I tell them they need a new one. That's worked well for me. So far, that's how I build my podcast Empire: fun! Capacitors! Yes, yes, literally on capacitors built on a giant pile of failed bloated, capacitors.

Okay, next question that I have for you is condensation because gun is a removal, is something that scares me to death with vrf you're still laughing. You haven't gotten over the capacitor thing yet. Well, I just find I feel, like a meme is gon na come out of this. Would you like a meme out of this? I would actually you do.

The thing is the other thing that you do because you're a very polite person, you do the same thing that Andrew Reese does when he's on the podcast, which is that as soon as I start talking, he just stops talking and you do that same thing and You've got to learn that, in order for this to be good, you've got to talk over me. That's the definition of a good podcast when you just get trampled as a host. All of my most popular podcasts are with Jim Bergman and he it just eviscerates me the entire time and it's great. So I don't keep that in mind.

Just a quick reminder that thinking about a meme for this situation, Brian on the top of the giant pile of capacitors, just like with a flag in it just be like Carlos, is actually way more truth in that. And then I'm willing to admit next question condensation, because condensate is the thing, at least in Florida, that terrifies me about ductless about vrf. All of it is that now you have all of these separate heads that are usually in at least in the ones. I've worked on in fairly inconvenient places if they were to start leaking.

I remember one of the first doctor systems we installed in a commercial location, we put in a office in a grocery store and then, like six months later, it was actually leaking on to their security computer that they placed right underneath this head and nobody was happy. So I've had a lot of terrified moments in my career since then so talk to me about condensate kind of State removal, or do you have issues with that? What do you run into so a lot of the units can be drained or can run your condensate. Two different ways under all the coils you're gon na have obviously condensate pans and, at one end the lower end. It's going to have a connection.

You can run a gravity drain and just drain it away like you wouldn't anything else, and you know the rules that apply. You can usually put a clean out blow it out with nitrogen. Do whatever you're gon na do a lot of the ducted units, so they make moderately high static, ducts, 0.5 inches 0.2 0.6 ducted units. They will have a pump in them, and so you just cap the gravity drain.

When the pump float sees it. There's condensate or hogs detecting condensate kicks on. It actually usually has a connection at the top of the unit. Then you're supposed to go over like a little hump and then it gravity drains from there and to be honest, I have had a grand total of zero calls that were related to a backup in the condensate system.

Now in Florida they probably would create a lot more condensate than the new here and it would be a larger part of I'm in Utah, Utah's, very dry and so in Florida or other humid places. I imagine it would be a more regular type of service call, but at that point they've got a pump. You can easily pull the pan. Look at the pump, replace the pump the units that don't have onboard pumps.

You can easily add a aftermarket pump. There's a whole different variety of them that are designed for mini splits and things like that. So in that regard I don't know if you'd have issues in Florida with that. I know here in Utah, where it's relatively dry, the only time I've had issues is.

There was one where the pump was unplugged for some reason and the resolution was plugging the pump and then it cleared the air and started back up and the other was it was thinking there was condensate when there wasn't, because it was detecting the condensate in a Really weird way had a thermistor in the pan, and so it was getting wasa cold air and I thought there was condensate and couldn't get rid of it and it tripped out but actual condensate. It's not been an issue now watch because of that. I'm gon na have one like in a week and I'm gon na be cursing you because I'm gon na have to like cut open these copper. It's blown out nitrogen.

Now. What kind of cursing will you be doing? Is it gon na be like modern profanity or is it gon na be like old-school 17th century cursing, like may the fleas of a thousand camels? Well, you need to understand that here in Utah, cursing is not cursing in other parts of the country. Cursing here would consist of, like I mean, look and like a strongly worded letter, something like that, like consternation to you, a strongly worded email. That said something like sincerely at the end.

Instead of god, bless well, that's 2018, so it'll be a meme but yeah all right right! Okay, if that happened, there's gon na be a meme it'll, be everywhere yeah. So those are you don't know, John I've dubbed him. The resident meme ologist of HVAC school. So anytime, there is something that's meme worthy John makes one recently I was actually shown as Vladimir Putin and one of his memes, which I think was intended to be positive, but I don't know I was interesting.

If you go to Russia, Vladimir Putin is like a hero over there. They show them in, like topless photos like wrestling a wolf like that's a very good thing, maybe ok, no memes of me topless wrestling wolf, please, ladies ladies calm down what type of buildings are these that you're working on primarily like what is the use of them? Typically, vrf could be installed in a lot of different applications. It's best suited to commercial buildings. Where you have some interior zone, that's going to be heated or cooled year-round.

Most commercial buildings have a core where they put conference rooms where they put all the cubicles where they put server rooms, electrical closets lights, there's a core of the building. That's gon na just need cooling, almost all the time. So for a VRS system I mean usually say: well, we got ta, have some cooling in there and it's an inefficient thing for a vrf system. In the middle of the winter I mean that's your heat source you're not pulling your heat from outside, typically you're, pulling that heat and then some from outside and then heating, the building with it so office spaces.

Doctor offices, I've seen it a lot in hospitality where you're gon na have apartment, building so old folks homes, I'm thinking through two different buildings. I have. I have one place that was like had ballet studios and a spa yoga studio stuff like that. Typically, it's gon na be commercial buildings.

Typically, it's going to be where you have some part of the building. That's not touching the exterior. You have small zones that are not necessarily sharing air to offices or separate areas that are blocked off in some way. Large open spaces, like I don't know, large grocery stores, grocery stores, banquet halls, warehouses.

Those are better served by different types of systems, not that I'm sure someone hasn't tried, but so usually it's some mid-range commercial atmosphere. Yes, a little bit of fragmentation, usually within the spaces, and so you name the applications that I think are best suited, maybe even on the residential side, maybe multi-family condo type applications in some cases, hospitality, medical office space; anything that you have a reasonable amount of diversity To as the diversity goes up between the zones, the efficiency of the system increases and as the efficiency increases, the compression actually work less hard and it's less wear and tear in the systems whenever they're in full-blown heating or full-blown cooling, that's the hardest. They work, but in the shoulder seasons, when it's part load some heating, some cooling North End of the building is heating. South End of the building is cooling all the windows, solar load.

That's when these things just shine, which is ironic because other systems that are sized for the absolute hottest or coldest part of the year, that's when they struggle because they're short cycle and their way oversized Viera systems really do well in that environment. So it's interesting. So, yes, diversity! That was one something that I learned early on when I went to vrf training with Mitsubishi, and that's just the idea that you have difference. Generally speaking, you're gon na have heating call in one's own cooling call in another zone, and you especially see this in commercial buildings where you may have a call for heating some of the central zones and then maybe even cooling on the external zones, or vice versa.

Depending on the load conditions, and then like you mentioned, you'll have diversity that will occur because of Sun, going across the horizon, etc, etc, and that is where these systems work really well, and I wanted you to address this quickly. This whole two pipe versus three pipe thing. You address that a little bit at the beginning of the podcast, but I think most of us have no clue how that works. How could you possibly run something that is operating in both heating and cooling on the same system, with only two pipes going inside the building that doesn't make any sense? The system I specialized in his mid BC city multi? It's a two pipe system, meaning there's two pipes between the branch, controller or the branch box and the outdoor unit.

Most other systems are three pipe, and the three pipes would be one is for discharge gas, which is high-pressure high-temperature. One is for suction gas, which is low pressure, low temperature and one is for liquid and depending on what mode they're in each indoor unit is going to be tapping into two of those, and some of them will have those pipe vertically to the unit. Some of them will have them pipe to smaller branch boxes in Mitsubishi sitting multi. So the two easiest - I guess you could say, would be just straight cooling, which is going to be doing the same thing and let's say you have 10 units and eight of them want cooling, any other tour off.

It's just gon na hot gas, from the compressor. The discharge gas is gon na go through the outdoor unit. We condensed liquid into the branch controller except extra sub cooling out to the unit's it does its thing meters at the metering devices, the LEDs picks up its super heat and then it's sent straight back to the compressor, just like a normal air. Conditioner same cycle heating same thing would run like a normal heat pump in heat mode hot gas, from the compressor sent inside on one of the lines through the indoor units D, superheated, phase change picked to liquid picks, up sub cooling and then goes to that metering Device and branch controller we're talking about it's going to be turning to a saturated, suction gas, no super heat, then it's going to go descent on the other line, so in heat mode discharge in suction back out, go outside run through the outdoor coil picks up its Super heat and then goes the compressor, so those are the two simple ones.

The two more complicated ones would be when you have mostly heating, with a little cooling and mostly cooling with little heating, so for mostly heating with a little cooling. It's the same basic mode, but instead of all of the liquid coming off of the heating units going to that metering device and being sent back out, some of it is then gon na be directed to the units that are cooling and their metering devices flash it To a section gas, pickup superheat and then it's just gon na mix that super heated section gas with the saturated section gas then go to the outdoor coil. So basically, what you're saying is that you could have some of your indoor heads functioning as condensers and some of them functioning as evaporators and rather than having that refrigerant, moving all the way back to the condenser. Instead, you're just Reed averting it and I imagine, there's a cornucopia, that's the word that comes to mind, a cornucopia of valves that make this happen.

I was thinking menagerie or assortment, but cornucopia works as well. All right we're gon na stay with cornucopia, a cornucopia of valves that would have to be present in order to make that happen. So that way, you can redirect that flow as necessary, but it makes sense that that would work and it would make sense it would happen whether or not you have primarily cooling or primarily heating you're, just taking a portion of it and instead of sending it back To the condenser you're, sending it back to a head that needs to operate so as an example, I'm just imagining. Okay, you have one head, that's operating as an evaporator coil, and so you have liquid coming in splashing off going into the evaporator coming back.

Well, actually, no, that is a little more challenging. Okay, now son I've run into a problem. I can imagine an easier the other way where you have it operating as a condenser. So it's operating is heating.

It goes through condenses changes to a liquid, and then you just take that liquid and move it into another evaporator flash it off, they're, saturated liquid, but I'm having a harder time imagining. So if it goes in, how are you going to heat it because it has to go to the compressor and be compressed for it to come out as a hot discharge? Gas? Ok, I'm missing this part, here's the tricky part! So, in the mode where it's mostly cooling, with a little heating, we needed to basically run like a regular air conditioner, where it's sitting in liquid and bring back section of the outdoor unit. However, we can't just send the liquid to the indoor units. I need heat that it's not gon na heat very well and that's usually where the third pipe would come in get where you'd have a separate line for discharge and liquid in the two pipe system.

They actually have it's like a chamber in the branch controller. It connects to the high pressure line, which, in this case, is a liquid line liquid line in some modes discharge line in some modes. So one of the two lines in the two pipe is dedicated suction. It's either saturated or superheated suction gas.

All the time. The other line, I'm just gon na call it a high pressure line cuz depending on the mode it's either liquid in or discharge gas in and when you say mode, it's like the majority mode, so the system has to decide it has to know. Are we majority cooling or are we a majority eating yeah? So it looks at the indoor units and says: what's calling? Well, it's all cooling, all heating. It can make a decision.

But if it's a mixture it'll pick either mostly heating, with a little cooling, we're mostly cooling with little heating and that changes. What valves are open? How it's gon na run and the tricky one that you'd get hung up on on the two pipe is when you're, mostly cooling with a little heating and what they do is in the outdoor unit. They condense the discharged gas mostly, but they don't sub cool it. So it's saturated and down the high pressure line.

They're gon na send a saturated liquid gas mixture and in this chamber, the hot gas. When that mixture is gon na go out, the top nice is just by gravity, and the liquids gon na go out the bottom and the hot gas that comes off. The top is gon na be sent out to the units that are heating and it's not very much heat. I mean it's not like discharge gas, but if everything needs cooling except for one little thing, it probably doesn't need much heat anyways and then the cooling is gon na go to liquid header and it's going to go out to all the units that are cooling then For that one unit, that's heating, it pulls the heat out, sub cool that or phase change, sub cool and then that liquid just joins goes back to the liquid header again and so that chamber, where it splits the phases, that's kind of what Mitsubishi has it lets Them do two pipes and I'm sure other manufacturers could use that, but why? Why do you, what Mitsubishi doing or they're gon na do what they're gon na do it's very interesting to see a technology develop between the different manufacturers, how they're all trying to accomplish the same thing but they're doing it all different ways? That reminds me a lot of in commercial refrigeration.

They have cool gas defrost instead of hot gas defrost and it's essentially the same thing: you're taking vapor off the top of a receiver and you're using that for defrost. Instead of using hot gas straight off the compressor, and so it sounds like a very similar type of thing here, where it's almost acting like that chamber is almost sort of like a receiver. It's not for that purpose, obviously, but yeah. That makes sense.

I get it in cooling mode, then you're gon na get liquid in and it's just all gon na go straight off the bottom into the liquid header and heating mode. It's all gon na be gas discharge, gas and it's all gon na go out the top. But in that one mode, it'll go and split and it'll actually separate in there. So it's pretty neat and I've never really had one fail or have issues it just kind of sits there and does its thing because it's not really any moving components in it.

But it's been interesting to read up on the literature and understand, what's happening in there, why it's significant and what makes it a little different from the other manufacturers anyways, what they're doing with the refrigeration circuit again, it's the same four components and compressor your condenser, your.