Speaker 1: Technology with tech Stuff from half staff works dot com.
Speaker 1: Hey there, and welcome to tech Stuff. I am your host,
Speaker 1: Jonathan Strickland. I am a producer executive at how stuff
Speaker 1: works dot com and I love technology and that's why
Speaker 1: I've been hosting the show for as long as I
Speaker 1: can remember. No, I seriously love tech, and recently, due
Speaker 1: to the hard work of Ramsey the Wonder producer, I
Speaker 1: was able to have a discussion with some people up
Speaker 1: on the rooftop click click click of the Pont City
Speaker 1: Market where we have an ice rink. Now, now, when
Speaker 1: I actually had this conversation, the ice rink had not
Speaker 1: been completely installed. There was a distinct lack of ice,
Speaker 1: for example. But it got me to thinking about doing
Speaker 1: a full episode about the technology then makes ice rinks
Speaker 1: possible in areas where it is not below freezing. I mean, obviously,
Speaker 1: you can have a natural ice rink if you happen
Speaker 1: to live someplace where it gets cold enough for a
Speaker 1: pond to freeze through thick enough where it's safe to
Speaker 1: do that. But as for indoor ice rinks like hockey
Speaker 1: ranks and ice skating rinks in general, you have to
Speaker 1: have a system there in order to make it work,
Speaker 1: So that's why I'm really going to explore today. Now,
Speaker 1: I'm not really familiar with this from a personal level,
Speaker 1: and that's because I live in Atlanta. I grew up
Speaker 1: essentially in the Atlanta area. I am a Southerner. We
Speaker 1: are not well known for our winter sports. We did
Speaker 1: once upon a time have an NHL hockey team called
Speaker 1: the Thrashers that got sold off to Winnipeg. But I'm
Speaker 1: not going to spend this entire episode grousing about how
Speaker 1: we don't have the Thrashers anymore. I could do that,
Speaker 1: but I won't. We do have a few temporary ice
Speaker 1: rink seasonal ice rinks that pop up during the winter, though,
Speaker 1: and I've never actually been on an ice rink. The
Speaker 1: closest experience I've had would be roller skating, and that's
Speaker 1: obviously similar but not the exact same thing as ice skating.
Speaker 1: But I do know I'm terrible at roller skating. I mean, absolutely,
Speaker 1: hilariously not graceful on roller skates, so I'm pretty sure
Speaker 1: i'd wipe out instantaneously on an ice skating rink. But
Speaker 1: I did want to learn more about how those are
Speaker 1: created and how they're maintained, particularly in places like here
Speaker 1: in the South where we have some of these outdoor
Speaker 1: ice skating rinks. And in case you weren't really familiar
Speaker 1: with us, our temperatures rarely dip below freezing, so it
Speaker 1: takes a lot of engineering to make sure that ice
Speaker 1: rink stays nice and icy. The tech to make an
Speaker 1: ice rink is pretty cool, pun intended, and a big
Speaker 1: component of it is essentially the same sort of tech
Speaker 1: that makes refrigerators or air conditioners work, only on a
Speaker 1: way bigger scale, but the same basic principles apply. So
Speaker 1: we're gonna talk a lot about the refrigeration cycle, and
Speaker 1: we're gonna talk a lot about heat exchangers. But first
Speaker 1: let's get some basic physics under our belts. Now, we've
Speaker 1: got to talk about thermal physics, as in the physics
Speaker 1: that are all about heat, and heat itself is a
Speaker 1: physical process. Heat is not something that is necessarily possessed.
Speaker 1: Heat is technically the transfer of energy from something of
Speaker 1: a high temperature to something else of a lower temperature.
Speaker 1: That process, that exchange, is in fact heat. So a
Speaker 1: lot of this stuff i'm gonna talk about you've probably
Speaker 1: heard plenty of times in basic science classes. But if
Speaker 1: you're like me and may have been a very long
Speaker 1: time since you've had a physics class, and you might
Speaker 1: need the refresher. And I always feel it's important to
Speaker 1: start simple and then you build from there. So first
Speaker 1: things first, heat always moves from an area of high
Speaker 1: temperature to an area of lower temperature within a system.
Speaker 1: That's how you do not have heat move from low
Speaker 1: temperature to high temperature. That would be crazy. It only
Speaker 1: goes high to low. That's just how our universe works.
Speaker 1: You cannot transfer the other way around. So any object
Speaker 1: that has a higher temperature than its surroundings within a
Speaker 1: system will gradually transfer heat to those surroundings and its
Speaker 1: own temperature, assuming there's not something actually generating the heat
Speaker 1: within this object will decrease until both the object itself
Speaker 1: and its surroundings will reach an equilibrium, that meaning they
Speaker 1: reach the same temperature. Similarly, if you have an object
Speaker 1: that has a lower temperature than its surrounding environment within
Speaker 1: a system, it will gradually warm up. Now this is
Speaker 1: not to say that cold is leaking out or escaping.
Speaker 1: Cold does not transfer. Only heat transfers. Heat from the
Speaker 1: environment moves into the object, ject gradually increasing its temperature.
Speaker 1: Until again it reaches an equilibrium. Now, in the real world,
Speaker 1: we would typically call this room temperature, because the systems
Speaker 1: we operate in on a day to day basis are
Speaker 1: these rooms and basic environments. So if you have a
Speaker 1: hot cup of tea and you leave it sitting on
Speaker 1: the counter for several minutes, it starts to cool because
Speaker 1: it's releasing that heat. That heat is transferring to its
Speaker 1: surrounding environment that is at a lower temperature than the
Speaker 1: hot cup of tea. Uh. Likewise, if you have a
Speaker 1: nice frosty beverage and you leave it on the counter,
Speaker 1: it will start to warm up. It'll start to absorb
Speaker 1: heat from its environment as it transfers in, until again
Speaker 1: it reaches that equilibrium. From a macro level, we could
Speaker 1: say that the heat is this flow of energy, So
Speaker 1: just keep that in mind. Generally speaking, if you want
Speaker 1: to make the base of an ice rink colder, technically
Speaker 1: this works for anything, but we're gonna use ice rink
Speaker 1: specifically because that's what this episode is about. If you
Speaker 1: want to make the base of an ice drink colder,
Speaker 1: you have to expose it to something that has a
Speaker 1: lower temperature than the rink base. So here in Atlanta,
Speaker 1: it's in I think the low sixties right now on fahrenheit,
Speaker 1: and we want to get the temperature of the base
Speaker 1: of that ice rink below the freezing temperature of water,
Speaker 1: which in fahrenheit would be thirty two degrees. It means
Speaker 1: that we have to expose that base of the ice
Speaker 1: rink to a temperature that's actually significantly lower than the
Speaker 1: freezing point for water in order to make this happen.
Speaker 1: Then the rink base will transfer heat to that lower
Speaker 1: temperature object, in other words, whatever we're using to cool
Speaker 1: down the base. Technically, what's happening is that the base
Speaker 1: is actually transferring heat to that system, and thus it
Speaker 1: will grow colder. Now, on principle, that's pretty simple, right,
Speaker 1: It's not a very amplicated thought. You just have to
Speaker 1: get something that's colder than what you're working with and
Speaker 1: move them within the same system, and then it will
Speaker 1: gradually make the other thing colder because they'll start to
Speaker 1: absorb the heat from that other thing. That's not that complicated.
Speaker 1: But then when you start actually looking at practical applications,
Speaker 1: you realize, all right, we've got to solve some pretty
Speaker 1: big problems. Requires a lot of engineering So, for one thing,
Speaker 1: if you want the ice rink to remain ice even
Speaker 1: if the surrounding temperature is above the freezing point for water,
Speaker 1: for example Atlanta, Georgia, and the winter tends to be that,
Speaker 1: you'll have to continuously chill the base of that ice rink.
Speaker 1: You can't just get it cold and leave it. You
Speaker 1: have to keep it cold. And since the base of
Speaker 1: the ice rink will continually transfer heat to that colder object,
Speaker 1: that colder object will eventually warm up. So whatever the
Speaker 1: system is that you're using to chill the base of
Speaker 1: the ice rink, it's absorbing heat. That means it is
Speaker 1: warming up. That means you have to have a continuous
Speaker 1: way to to keep that that's system more cool, to
Speaker 1: chill it, to use a chiller if you will, that's
Speaker 1: what they're called. Uh So these are actually pretty complicated. Now.
Speaker 1: I keep saying colder object because not all ice rinks
Speaker 1: are equal. They're not all exactly the same. They use
Speaker 1: the same principle, but the actual application is different. So,
Speaker 1: for example, if you wanna hockey rink, like a standard
Speaker 1: hockey rink in HL hockey rink, you're talking about typically
Speaker 1: a a base. There's a concrete base under which you
Speaker 1: have a network of steel pipes, and the steel pipes
Speaker 1: carry an extremely cold liquid, something that's below the freezing
Speaker 1: temperature of water. We'll get into that a little bit later,
Speaker 1: and that in turn pulls heat away from the concrete base,
Speaker 1: making it colder than the freezing point for water. You
Speaker 1: can then add water on top of the concrete base
Speaker 1: and start building up layers of ice. Others are a
Speaker 1: little bit different. The one that's up on the rooftop
Speaker 1: of our building actually has a series of plastic tubes
Speaker 1: that are carrying an extremely cold liquid in them being
Speaker 1: pumped underneath the surface of the ice rink, and that's
Speaker 1: what allows the water to freeze even in temperatures that
Speaker 1: are above the freezing point for water. And essentially pour
Speaker 1: water on top of this or otherwise distribute water on
Speaker 1: top of it. It's a little more precise than just pouring,
Speaker 1: and you get your ice rink. Uh So, generally speaking,
Speaker 1: same approach, just slightly different applications. Now we have to
Speaker 1: create a system that will hold a temperature below the
Speaker 1: freezing point of water. Now that presents itself with a
Speaker 1: few challenges. First, you have to figure out, all right,
Speaker 1: what substance are we going to use. Clearly, we can't
Speaker 1: just use plain old water because if we did the
Speaker 1: water in our system to try and absorb heat, that
Speaker 1: would freeze and then you wouldn't be able to move
Speaker 1: it through your pipe system. So you can't just use
Speaker 1: plane old water. You would need to have a liquid
Speaker 1: that has a lower freezing temperature than water does. So
Speaker 1: one way you could do that is by adding stuff
Speaker 1: to water in order to lower its freezing point. So
Speaker 1: salt is a good example. Saltwater has a lower freezing
Speaker 1: point than freshwater, and that freezing point is dependent upon
Speaker 1: how much salt concentration there is within that water mixture.
Speaker 1: So some hockey rinks will use a briny mixture, meaning
Speaker 1: they've got some salt content in the water to lower
Speaker 1: that freezing temperature. Um if you have fresh water that
Speaker 1: freezes at thirty two degrees fahrenheit or zero degrees celsius, seawater,
Speaker 1: which obviously is not the same thing as being used
Speaker 1: in hockey rink systems, uh seawater freezes at twenty eight
Speaker 1: point four degrees fahrenheit or minus two degrees celsius. So
Speaker 1: seawater has a salinity that's salt content of about three
Speaker 1: point five percent. That is not as salty as water
Speaker 1: can get. Though. You can keep adding salt into water
Speaker 1: up to the point that the salt makes up about
Speaker 1: twenty three point three percent of the weight of the mixture.
Speaker 1: So at that point you reach what's called saturation. You
Speaker 1: cannot put more salt into that mixture. It will never dissolve.
Speaker 1: So at twenty three point you hit that maximum salinity. Now,
Speaker 1: at that concentration, saltwater would have a freezing temperature of
Speaker 1: minus twenty one point one degree celsius or minus five
Speaker 1: point nine eight degrees fahrenheit, So very different. Right, You're
Speaker 1: talking about a vast array of temperatures there, and again
Speaker 1: it's all just based on the amount of salt in
Speaker 1: that water. So a lot of ice ranks, like I said,
Speaker 1: a lot of hockey ranks, use a briny mixture as
Speaker 1: the cooling mechanism for the base of the rank. And
Speaker 1: now the ice itself that's on the the rank, that's
Speaker 1: pure ice. That's just water that doesn't have any salt content,
Speaker 1: and at all, the only thing that has the salt
Speaker 1: content is the system underneath the rink that is at
Speaker 1: a lower temperature in order to allow the ice to
Speaker 1: form the one that's actually being or one that's in
Speaker 1: use now on the rink. When we went up to talk,
Speaker 1: they were still putting this all together. Doesn't use a
Speaker 1: briny mixture. Instead, it uses glycol, which is a type
Speaker 1: of alcohol, and glycol also has a lower freezing point
Speaker 1: than water. In fact, glycol will remain a liquid until
Speaker 1: you hit about negative seventy four degrees fahrenheit, which is
Speaker 1: about negative fifty nine degrees celsius. So if you can
Speaker 1: cool glycol down well below waters freezing temperature, but still
Speaker 1: above the freezing temperature of glycol itself, you're in business.
Speaker 1: You can keep pumping liquid glycol that's at a very
Speaker 1: low temperature at the very base of your ice rink,
Speaker 1: and that will provide the heat sink to pull heat
Speaker 1: away from water and allow it to freeze. But this
Speaker 1: leads us to our second big problem to solve. How
Speaker 1: do you get the cooling liquid to that low temperature.
Speaker 1: How you keep your glycol or your briny mixture, and
Speaker 1: they'll temperature lower than the freezing point for water. If
Speaker 1: the water you are adding is constantly transferring its heat
Speaker 1: to the system, how do you then get rid of
Speaker 1: that heat, because if you don't do that, you're cooling
Speaker 1: pipes will gradually warm up and then your ice rink
Speaker 1: will just become a very shallow swimming pool and people
Speaker 1: will not have very much fun. That is where the
Speaker 1: chillers come in. Chillers are all about transferring heat, so
Speaker 1: as you can siphon it away from one area and
Speaker 1: dump it in another area. You cannot destroy energy, but
Speaker 1: you can move it from one place to another. So
Speaker 1: you can't destroy heat, but you can pull it from
Speaker 1: one location and disperse it into a different location. Chillers
Speaker 1: do this by taking advantage of thermal physics. And there's
Speaker 1: several different types of killers that use slightly different approaches,
Speaker 1: some of them dramatically different approaches, but they all have
Speaker 1: essentially the same end goal, which is to facilitate heat transfer.
Speaker 1: We're gonna look at a general approach and talk about
Speaker 1: the types of chillers you're likely to run into if
Speaker 1: you were, I don't know, going to an ice rink
Speaker 1: or installing a massive HVAC system for an office building.
Speaker 1: So think of chillers as three loops that are adjacent
Speaker 1: to one another, but they don't connect to each other.
Speaker 1: So almost like three rubber bands that are very close together.
Speaker 1: Within one loop, you have the chilled liquid. That is,
Speaker 1: this is the stuff that is creating the heat sync,
Speaker 1: that's pulling the heat away from whatever it is that
Speaker 1: you want to cool down. This might be an air
Speaker 1: conditioning system, or it might be again the basis the
Speaker 1: foundation for your ice rink. Uh. So you've got that,
Speaker 1: You've got the second loop that takes the heat gathered
Speaker 1: from the first loop. So that first loop starts to
Speaker 1: heat up as it's absorbing this heat. You've got to
Speaker 1: find a way to remove that. You've got to find
Speaker 1: a way to dump that heat someplace. There's a second
Speaker 1: loop that it essentially does that. It takes the heat
Speaker 1: from the first loop and then finds a convenient spot
Speaker 1: to dump it. And then you have a third loop
Speaker 1: that is your refrigerant that kind of acts as the
Speaker 1: facilitator between loops one and two. In fact, it's the
Speaker 1: most important component of the entire system, is your refrigerant
Speaker 1: uh loop. Now there are four different pieces to the
Speaker 1: chiller system. Within that refrigerant loop then make all of
Speaker 1: this possible. You have a compressor, you have a condenser,
Speaker 1: you have an expansion valve and you have an evaporator.
Speaker 1: And this leads us to another element of thermal physics,
Speaker 1: which is if you crank up pressure on a gas,
Speaker 1: for example, you not just increase the pressure of that substance,
Speaker 1: you also increase its temperature. And it also means that
Speaker 1: you can push up the boiling point of a substance
Speaker 1: by putting it under pressure, which is also a great
Speaker 1: song with Freddie Mercury and David Bowie. So if you
Speaker 1: take a gas and you pressureize it enough, you can
Speaker 1: convert that gas into a liquid, even if the temperature
Speaker 1: of the substance is above its normal boiling point at
Speaker 1: regular air pressure. So it will end up condensing into
Speaker 1: a liquid, whereas it would normally evaporate into a gas
Speaker 1: under that under a normal pressures, as long as you're
Speaker 1: cranking up the actual pressure of the gas. So here's
Speaker 1: how I think about it. On a molecular level, it's
Speaker 1: really easy to understand the behavior of solids, liquids and gases.
Speaker 1: A solid substance has its molecules pretty much locked into place.
Speaker 1: I mean, there's always some little movement, but it's more
Speaker 1: or less locked into place. They hold their positions relative
Speaker 1: to each other that keeps a solid consistent. But a
Speaker 1: liquid has molecules that can move around more freely. They
Speaker 1: spread out a bit, they get to wander around, they
Speaker 1: test their boundaries because the liquid always is going to
Speaker 1: take the shape of whatever container it is in. Then
Speaker 1: a gas goes even further with molecules spreading out even more.
Speaker 1: But if you do put that gas under pressure, you're
Speaker 1: effectively forcing those molecules closer together as if they were
Speaker 1: in a liquid. So if you do that enough, the
Speaker 1: gas condenses into a liquid. You push those molecules together
Speaker 1: enough to convert it into its liquid form. So how
Speaker 1: does a chiller take advantage of this? All? Right, this
Speaker 1: is gonna be a little tricky to describe without the
Speaker 1: use of visual aids, but I'm gonna do my best.
Speaker 1: So let's just imagine the system as simple as we
Speaker 1: possibly can. Imagine a rectangle, and it's wider than it
Speaker 1: is tall. So you've got a wide rectangle. Now in
Speaker 1: the center part of the base of the rectangle, that
Speaker 1: bottom border of the rectangle, just imagine a circle right
Speaker 1: in the center of that. That circle is going to
Speaker 1: represent our compressor. Now at the top of the rectangle,
Speaker 1: opposite of our compressor will draw a little triangle, and
Speaker 1: that triangle is going to represent the expansion valve. So
Speaker 1: you can think of these as two gates. They keep
Speaker 1: the pressure different on either side of the gates. On
Speaker 1: the right side of this rectangle, we're going to imagine
Speaker 1: that's the condenser, and on the left side, we're going
Speaker 1: to imagine that that is the evaporator. So refrigerant moves
Speaker 1: from the evaporator side through the condenser side via the compressor.
Speaker 1: So you have the refrigerant moving from evaporator into compressor
Speaker 1: where it gets compressed, thus the name, and then pushed
Speaker 1: over to the condenser side. So we're going to take
Speaker 1: a journey with the refrigerant to understand how this works
Speaker 1: from a technical perspective. From the evaporator side, just as
Speaker 1: you get to the compressor, that refrigerant before it goes
Speaker 1: through the compressor is a low pressure arm gas. Typically,
Speaker 1: the compressor then compresses this gas so that the output
Speaker 1: on the other side, on the condenser side is a
Speaker 1: high pressure hot gas. This hot gas then moves through
Speaker 1: the condenser and that's typically a long length of pipe
Speaker 1: or tubing that folds back and forth on itself. If
Speaker 1: you've ever looked into the back of a refrigerator or
Speaker 1: in an air conditioning unit, you've probably seen this where
Speaker 1: you've seen these these pipes that do these tight s
Speaker 1: curves over and over and over again. Well, that's the
Speaker 1: way it's laid out. In a condenser. The high temperature,
Speaker 1: high pressure gas moves through this length of pipe and
Speaker 1: it can start to transfer some of that heat. Some
Speaker 1: of it gets transferred straight through the pipe, some of
Speaker 1: it typically gets transferred through fins that are uh connected
Speaker 1: to the pipes so that it can draw heat away
Speaker 1: through conductivity. It's it's conducting the heat and you then
Speaker 1: have um a fan typically that blows air across the
Speaker 1: system that uses convection to pull heat away as well.
Speaker 1: So this gas starts to lose some of that temperature.
Speaker 1: As it's moving through this series of s curves, it's
Speaker 1: transferring heat to the air around it. Now, the higher
Speaker 1: pressure means that as this happens, the gas begins to
Speaker 1: condense into a liquid. As it makes its journey through
Speaker 1: this part of the loop, the liquid is still under
Speaker 1: a lot of pressure that you can't really pressurized liquid
Speaker 1: the way you can with gases, but it's still under
Speaker 1: a great deal push, you could think of it in
Speaker 1: that sense, um, but it's reaching more of a regular temperature.
Speaker 1: At the end of the condenser side, you have that
Speaker 1: expansion valve which leads to the evaporator side. Now, the
Speaker 1: reason its valve is so that it can again create
Speaker 1: this partial seal. It's sealed. Whenever it's shut. You have
Speaker 1: a low pressure side on the other on the evaporate
Speaker 1: raator end of this loop the circuit, if you think
Speaker 1: of it that way. So you have high pressure on
Speaker 1: the condenser side, low pressure on the evaporator side. That
Speaker 1: expansion valve allows for one way travel, so it goes
Speaker 1: from condenser to evaporator, and pressure, like temperature, is all
Speaker 1: about moving from areas of high concentration to low concentration.
Speaker 1: So the expansion valve allows this pressurized substance, this refrigerant,
Speaker 1: to pass through into that low pressure side, the evaporator side,
Speaker 1: and when it does, it suddenly finds itself with a
Speaker 1: lot more room to spread out than on the high
Speaker 1: pressure side. Right Suddenly it doesn't have that high pressure
Speaker 1: to cram it together, and so the molecules of the
Speaker 1: refrigerant end up spreading out and as a result, the
Speaker 1: temperature begins to drop, so at the beginning of the
Speaker 1: refrigerant journey around the evaporator, it becomes a low pressure
Speaker 1: cold liquid, and as it moves through the evaporator, it
Speaker 1: starts to absorb heat from the system. Whatever it is
Speaker 1: you're trying to cool. In this case, it would be
Speaker 1: the the stuff that's running underneath the rink, whether it's
Speaker 1: the brine or whether it's glycol, that would be tangential
Speaker 1: to this refrigerant system, and the refrigerant would be absorbing
Speaker 1: the heat from there, and as a result, the refrigerants
Speaker 1: starts to boil off, it starts to evaporate, thus the
Speaker 1: name of operator. In air conditioning systems, this heat would
Speaker 1: be from the air of whatever area you were trying
Speaker 1: to cool, But in the case of the ice rink
Speaker 1: on the roof of our building, the heat is in
Speaker 1: that glycol that's running through the tubes that are under
Speaker 1: the rink itself. The refrigerant boils as it moves through
Speaker 1: this part of the loop and evaporates, and that turns
Speaker 1: into the low pressure warm gas that we started off
Speaker 1: with when I began talking about this refrigerant in the
Speaker 1: first place. That low pressure warm gas that immediately moves
Speaker 1: through the compressor and becomes the high pressure, high temperature gas.
Speaker 1: So we're back at the beginning, and we just keep
Speaker 1: going through. It's a close system, so it doesn't go
Speaker 1: anywhere else. The refrigerant does not mix with any of
Speaker 1: the other loops. It just continuously goes through this process.
Speaker 1: Now the glycol again access that separate loop, comes into
Speaker 1: close contact with a refrigerant, but it never actually shares
Speaker 1: a common line with it, so you never mix them together.
Speaker 1: The glycol will transfer heat over to the refrigerant, and
Speaker 1: because it's transferring heat, the glycoal itself becomes colder as
Speaker 1: a result, or if you prefer, the temperature decreases due
Speaker 1: to this heat transfer. The glycol then moves through its
Speaker 1: own pump to travel underneath the rink through lots of tubes.
Speaker 1: I mean there were hundreds of these tubes underneath the rink,
Speaker 1: and it absorbs the heat from the environment as it
Speaker 1: moves through until it gets back to the heat exchanger
Speaker 1: part of the loop, and then again transfers heat to
Speaker 1: the refrigerant and goes all the way through it again.
Speaker 1: So again closed loop systems. It's just pumps moving liquid
Speaker 1: through at this point. Typically you then would have a
Speaker 1: third loop, and this is the one that picks up
Speaker 1: all the heat that was pushed out from the condenser
Speaker 1: side of that refrigerant when it was that high pressure,
Speaker 1: high temperature gas. So there's some that are air cooled,
Speaker 1: but a lot of them end up being water cooled,
Speaker 1: so you have this water loop again on that side
Speaker 1: of it. You can use water in this particular system
Speaker 1: because you're not you're dealing with temperatures that are well
Speaker 1: above the freezing point of water. You just have to
Speaker 1: make sure that the water is at a lower temperature
Speaker 1: than the gas going through the condenser, because again, heat's
Speaker 1: going to only move from high temperature to low temperature.
Speaker 1: So if the water you're using is high temperature and
Speaker 1: the condenser is at a high temperature, it's not very efficient.
Speaker 1: You need the water to be cool enough to actually
Speaker 1: pull heat away, or rather to accept heat that's being
Speaker 1: rejected from the condenser. This water would then typically be
Speaker 1: pumped up to some sort of cooling mechanism like a
Speaker 1: cooling tower, and these are the big things you see
Speaker 1: on top of buildings that often emit enormous amounts of
Speaker 1: steam on cold days. If you've ever seen that. That's
Speaker 1: typically a cooling tower on the top of a building
Speaker 1: that's part of the HVAC system. The hot water will
Speaker 1: go into the cooling tower. It drips down over fins
Speaker 1: that are inside the cooling tower. You typically have a
Speaker 1: fan or maybe a couple of fans at the top
Speaker 1: of the cooling tower that is drawing air into the tower.
Speaker 1: Their vents along the side that pull air in. The
Speaker 1: air moves over these fins that have the hot water
Speaker 1: on them, thus cooling the water, some of it evaporating
Speaker 1: away and then ejecting out the top of the cooling
Speaker 1: tower being pushed out through that fan. So it's kind
Speaker 1: of like a vacuum cleaner, but instead of sucking up dirt,
Speaker 1: it's sucking up heat and air from the water, or
Speaker 1: heat from the water, but air in general, and blowing
Speaker 1: it up through the top. The cooling water ends up
Speaker 1: dripping down these fins, typically collects at a basin at
Speaker 1: the at the base of the cooling tower and then
Speaker 1: drains back down into the system. Uh and then back
Speaker 1: down to the heat exchange, your part of the chiller
Speaker 1: that I was just talking about. So that's your basic
Speaker 1: parts of a chiller. And again it's the same principle
Speaker 1: that's working with things like refrigerators, it's working with air
Speaker 1: conditioners and also ice skating rinks. Now I've got a
Speaker 1: lot more to say about the technology behind ice skating
Speaker 1: rinks and maintaining them, but before I do any more
Speaker 1: of that, let's take a quick break to thank our sponsor.
Speaker 1: All Right, So we've talked about how to get the
Speaker 1: temperature down low enough to freeze water and keep it
Speaker 1: at a temperature where you still have solid water a k. A. Ice.
Speaker 1: But how do you fill up the ice rink. The
Speaker 1: answer is that you do it very carefully, or if
Speaker 1: you prefer, meticulously and slowly. So a large permanent ice
Speaker 1: rink typically will have that concrete foundation, and underneath that
Speaker 1: you have a network of pipes that carry the cool
Speaker 1: liquid that keep the concrete foundation nice and chili. The
Speaker 1: concrete will be at a temperature that is below the
Speaker 1: freezing point of water. Uh. You fill up the rink
Speaker 1: by spraying it with a fine mist of water onto
Speaker 1: the concrete layer to start off with the temperature of
Speaker 1: the concrete so low that those tiny water droplets pretty
Speaker 1: much freeze as they make contact with the concrete, it
Speaker 1: doesn't take along at all for it to freeze to
Speaker 1: the surface. The first couple of layers of ice are
Speaker 1: always extremely thin, So for a typical hockey rink that
Speaker 1: uses this concrete approach, you're talking about an inch thick,
Speaker 1: which is about point eight five millimeters, and once those
Speaker 1: layers are down, you paint it. So most ice rinks
Speaker 1: will lay down a layer of paint on those first
Speaker 1: couple of layers of ice. This helps do a few things.
Speaker 1: For one, it hides the base of the ice rink away,
Speaker 1: so you're not looking at clear ice and seeing a
Speaker 1: concrete floor, or in the case of the ice rink
Speaker 1: that's on the roof of our building, you wouldn't see
Speaker 1: a series of tubes that are pink because call has
Speaker 1: a the glyde call they're using has a pink tent
Speaker 1: to it, so you would otherwise see just lines and
Speaker 1: lines and lines of pink tubes. So they paint the
Speaker 1: ice that it obscures that. It also will allow for
Speaker 1: good contrast with any logos or words that you want
Speaker 1: to paint on the ice rink. So, for example, with
Speaker 1: hockey rinks, you would typically paint the name of the
Speaker 1: hockey team on there, maybe put their logo on, maybe
Speaker 1: a sponsor logo could go on there. But you want
Speaker 1: there to be good contrast, so that's why you have
Speaker 1: that white base. Also, it creates great contrast for the
Speaker 1: puck in hockey because you want to be able to
Speaker 1: see that if you're a player or or an observer. Really,
Speaker 1: So after that layer of paint would come another layer
Speaker 1: of ice. This one is a little more thick. It
Speaker 1: is one of an inch thick, that's about one point
Speaker 1: six millimeters, and that acts like a seiler for that
Speaker 1: layer of paint that was just laid down, and then
Speaker 1: you could put more paint down on top of this layer.
Speaker 1: So this is where you would paint logos or the
Speaker 1: lines and circles and arcane symbols that make up the
Speaker 1: rules of hockey that I never got a chance to
Speaker 1: understand because Atlanta's team was taken from us before I
Speaker 1: could ever get a full grasp on the rules. And yeah,
Speaker 1: I know, I said I wouldn't talk about it, but
Speaker 1: I'm still angry about it. Anyway, after that you would
Speaker 1: add your final layer of ice on top. But this
Speaker 1: actually would happen in several stages, so it's one solid layer,
Speaker 1: but it's done in phases. This is the actual surface
Speaker 1: that people would skate upon. Now. Typical hockey rank, which
Speaker 1: again is much larger than the one that we have upstairs,
Speaker 1: would require between twelve thousand and fifteen thousand gallons of water,
Speaker 1: that's forty thousand to fifty seven thousand liters. Most of
Speaker 1: that water gets added in that final layer. The overwhelming
Speaker 1: majority of the water is added in that last layer.
Speaker 1: And whereas the early layers get added as a fine missed,
Speaker 1: the final one is a bit less delicate. They typically
Speaker 1: will just use a flooding hose to pour water out
Speaker 1: on top of the rink, and we're talking about ten
Speaker 1: thousand gallons of water at a rate of about five
Speaker 1: hundred to six hundred gallons per hour, which means it
Speaker 1: can take about twenty hours or so to add that
Speaker 1: final layer to the rink. And according to Don McMillan,
Speaker 1: whom hell Stuff Works, interviewed for an article on how
Speaker 1: ice rinks work, most rinks will allow each five hundred
Speaker 1: or six hundred gallon amount in that hour to freeze
Speaker 1: completely before they start adding more water. So again in phases,
Speaker 1: and that helps maintain a really good quality of ice
Speaker 1: and ice quality is really a thing. You can have
Speaker 1: good ice and you can't have bad ice. If your
Speaker 1: temperature isn't right, you're gonna have some issues. So for example, um, outside,
Speaker 1: if you don't have the right temperature, it's gonna start melting.
Speaker 1: You'll have some slushy ice at the top, and that's
Speaker 1: not great for skating. Um if you have really high humidity,
Speaker 1: you're gonna end up with a lot of fog over
Speaker 1: the ice, which happens here because we have a lot
Speaker 1: of humidity in Atlanta. And uh, it's pretty spooky looking
Speaker 1: in the morning to walk up to Pont City Market
Speaker 1: and see the the the mist pouring off the top
Speaker 1: of the building. Professional ice skaters tend to like their
Speaker 1: ice at a relatively warm to twenty degrees fahrenheit at
Speaker 1: the surface. That's minus three point three three to minus
Speaker 1: two point to two degrees celsius. Hockey players like it
Speaker 1: a little colder because the ice is harder, it's more resilient,
Speaker 1: doesn't grip the ice skates quite like the softer, less
Speaker 1: cold ice does. They prefer the surface to be closer
Speaker 1: to twenty four to twenty six degrees fahrenheit or minus
Speaker 1: four point four four to minus three point three three
Speaker 1: degrees celsius. Now, I had a chance to chat with
Speaker 1: the project manager for the ice rink installed on the
Speaker 1: roof of our building, and we cover some of the
Speaker 1: stuff I just mentioned, but I think it's a pretty
Speaker 1: interesting discussion, including all the work that was required to
Speaker 1: install an ice rink on the roof of a nine
Speaker 1: story building in Atlanta, Georgia, and just the amount of
Speaker 1: sheer effort it required to do that. So here's what
Speaker 1: he had to say. Oh and just so you guys know,
Speaker 1: we were talking up on the roof on a windy days,
Speaker 1: so it was also during while you know, construction, they
Speaker 1: were still playing the ice ring together, so the audio
Speaker 1: quality is a bit atmospheric. But here he goes, so basically,
Speaker 1: you got to have a level surface. Obviously, if you're
Speaker 1: gonna make guys it's greight water, you can have it
Speaker 1: running downhill. So we were fortunate enough to already have
Speaker 1: a basically a perfectly leveled deck up here. So then
Speaker 1: we put in foam insulation over that deck, uh, and
Speaker 1: then a biscuen plastic and then we put these mats together,
Speaker 1: and each of these tubes is a circulating system that
Speaker 1: will run the glacoll pump pressurized probably minus ten twenty
Speaker 1: degree claike all through and as the glacoll is running
Speaker 1: through it and freezing, you basically take your standard garden
Speaker 1: host and start missing water. And as soon as the
Speaker 1: water hits that minus twenty degree glycol to being, it
Speaker 1: starts to freeze. And so you start building that that
Speaker 1: base of ice. And they'll basically take it from from
Speaker 1: below the glacoll t being that you see here to
Speaker 1: about a half inch above it, and then they'll paint
Speaker 1: it white so that you don't see everything all this
Speaker 1: pink glacol underneath. So then they'll put after they've got
Speaker 1: that basecoat of white paint on it, then they'll put
Speaker 1: another layer of clear ice on it. So it looks
Speaker 1: just like any other ice skating rink in America, hockey
Speaker 1: rink that you would see on TV. And if we
Speaker 1: wanted to, you could paint lines, or we could have
Speaker 1: a sponsor, we would have a how how stuff works
Speaker 1: out there, and you know, logo in the middle and
Speaker 1: everybody skating would be skating over it, and that's pretty
Speaker 1: much that. That's you know, that's the the end of
Speaker 1: the process, and it's pretty simple. It's what happens prior
Speaker 1: to that where all the engineering comes into play and uh,
Speaker 1: all the hard work happens. So in order for us
Speaker 1: to create this on the roof, a lot had to happen.
Speaker 1: We had a hundred and twenty ton chiller that we
Speaker 1: had to crane to the roof, and so that was
Speaker 1: we had a three hundred foot crane basically that we
Speaker 1: hooked that up to. But before we did that, you
Speaker 1: just can't set pounds plus another three thousand pounds of
Speaker 1: glycol on a roof. It has to be engineered. So
Speaker 1: we did structural engineering analysis and then built a platform
Speaker 1: that would handle the weight the distribution, because not only
Speaker 1: is it weight, you also need a little shock absorbers
Speaker 1: in there to handle any of the vibrations because once
Speaker 1: you tie into the columns and the beams, you don't
Speaker 1: want the neighbors below hearing or feeling any any vibration
Speaker 1: and rattling. So we isolated that system, craned up the chiller,
Speaker 1: and uh and at that point we're running six inch
Speaker 1: steel pipe from the chiller up to the rink here
Speaker 1: and it's a closed system. So it's just a massive
Speaker 1: circulation of glycol. Because we had to locate our chiller
Speaker 1: UM further than about twenty feet from the rank. We
Speaker 1: had to put a massive pump on it too. So
Speaker 1: the chillers themselves have a limited pressure capability for runs,
Speaker 1: but our run was so long, we we put a
Speaker 1: huge pump on it so that we get the constant
Speaker 1: pressure that we need and UM and that we maintain
Speaker 1: our ability to keep this thing frozen. We're lucky that
Speaker 1: we're under a tent. If we were outside in Atlanta,
Speaker 1: you know, we we don't have a lot of days
Speaker 1: of constantly below freezing here and in the sunshine it
Speaker 1: would probably melt the ice at some of the some
Speaker 1: of the other outdoor rinks struggle with that. UM, we
Speaker 1: will not have any issues. I'm told by the experts.
Speaker 1: Without rect sunlight on our rank that we should have
Speaker 1: a great surface. We could probably do it all year round,
Speaker 1: believe it or not. UM. I know that this company
Speaker 1: UH does things worldwide and they have outdoor outdoor skating
Speaker 1: in San Diego, so and they say to run that
Speaker 1: in the summertime there. So you just have to have
Speaker 1: a you know, it's all about your how big your
Speaker 1: chiller is, and how big your rank is. In order
Speaker 1: to to make that happen, and then all the six
Speaker 1: inch piping of course had to be highly insulated. Uh.
Speaker 1: You don't want to lose any of your value, your
Speaker 1: temperature values. You know, steel obviously would would bleed out
Speaker 1: and into the ambient air temperature. So we've got about
Speaker 1: the two inches of insulation around all the piping. Uh.
Speaker 1: From an electrical standpoint where four naty volts three phase uh,
Speaker 1: so lots of lots of juice to run all this,
Speaker 1: as you're probably aware, you know, the bigger equipment, anything
Speaker 1: that involves heating and cool really it's gonna pull a
Speaker 1: lot of amps and it's gonna need a lot of
Speaker 1: a lot of voltage. So we we actually ran additional
Speaker 1: power up here on the roof in order to make
Speaker 1: that happen. Can't just plug it into the outlet on
Speaker 1: the wall, regrettably, because running power from the west side
Speaker 1: of the building to over here is it's it's pricey
Speaker 1: at at the thirty bucks a foot just for the
Speaker 1: just for the wire, just for the cable. So they
Speaker 1: the power was was a disappointment. My landlord has been
Speaker 1: very helpful with with helping us out on some of that.
Speaker 1: So basically what we're looking at here for for people
Speaker 1: who may not be aware of how this all works,
Speaker 1: we're looking at essentially a heat exchanger. You've got your glycol,
Speaker 1: which has a lower freezing point than water, so you
Speaker 1: can lower that temperature of the glycol much lower than
Speaker 1: the freezing point of water. You run that through the system,
Speaker 1: water hits it. Obviously, the heat transfers into the glycoal system,
Speaker 1: which is so cold and so massive and being up
Speaker 1: so quickly that it's not effectively raising the temperature of
Speaker 1: glycol enough for it to affect uh. But it's not
Speaker 1: like you're going to have one part of the rink
Speaker 1: that's slushy, whereas the rest of it's all all nice
Speaker 1: and solid. It goes, pumps through the system, hits the chiller,
Speaker 1: reduces the temperature of the glycol back down to what
Speaker 1: you wanted at the top, goes right back in because
Speaker 1: it's a closed loop, and just continuously pumps through to
Speaker 1: keep that water at that that below freezing temperature, so
Speaker 1: that you have anice solid rink. Is that more or
Speaker 1: less what we're looking at. That's exactly what we're looking
Speaker 1: at here, And and In fact, the chiller has got
Speaker 1: it the sensors on it, and it will monitor the
Speaker 1: pressure and it will also monitor the temperature. So it's
Speaker 1: kind of a smart system in order to be efficient
Speaker 1: to tell itself exactly what it needs to do to
Speaker 1: maintain the conditions that we're looking that you just described
Speaker 1: out here. Well, that's great because this is exactly the
Speaker 1: same sort of principle that you would see on things
Speaker 1: like air conditioners or a refrigerator, just on a much
Speaker 1: more are massive scale. And it temperature is far lower
Speaker 1: than what you would I mean, I like a nice
Speaker 1: cool man cave, but minus twenties is low even for me. Yeah,
Speaker 1: you know, it's not something you want to walk around
Speaker 1: barefoot on in the garage or in your cave. So
Speaker 1: that's great. About how long would it take to go
Speaker 1: from from dry to full rank? Uh? Knowing that this
Speaker 1: is going through phases right once, once we're at this
Speaker 1: point where the system is set up, the grid is
Speaker 1: laid down, and once we flip that compressor on within
Speaker 1: an hour, we're gonna start making ice. As soon as
Speaker 1: we reach the right tempts that are circulating through the system,
Speaker 1: we're gonna start spraying down that that first coat of
Speaker 1: water in order to uh to build up that ice.
Speaker 1: So it should happen very quickly. Uh, you know, we
Speaker 1: probably will. It'll take hours, of course to build up inches.
Speaker 1: Will probably get to about three inches of ice out here.
Speaker 1: That may take some time. But again, because we're not
Speaker 1: interact sunlight, we're and it is cool at night. So
Speaker 1: if we start this in the afternoon and work into
Speaker 1: the evening, we should have a solid rink within a
Speaker 1: matter of four or five hours up here to skate on.
Speaker 1: That's incredibly one of the do you happen to know
Speaker 1: the dimensions of this rank? Yes, this rank is fifty
Speaker 1: by seventy, so we're right at suare feet here, So
Speaker 1: just five hours or less for that much that much
Speaker 1: square footage is really impressive when you sit there and
Speaker 1: you think about the energy requirements, as you were saying,
Speaker 1: just for the equipment is incredible, but if we're talking
Speaker 1: about just physics, the energy requirements to remove that much
Speaker 1: heat so that you can convert water into ice for
Speaker 1: that much square footage, it's it's phenomenal and it's an
Speaker 1: elegant solution to I'm sad that my listeners won't be
Speaker 1: able to see this. Well, we'll share some images on
Speaker 1: social as well to kind of get a look at
Speaker 1: how this works. But when you see it and you
Speaker 1: see the solution that was proposed, from an engineering perspective,
Speaker 1: it is simple and elegant and yet incredibly effective to
Speaker 1: be able to turn that much water into that much
Speaker 1: ice that quickly. Um Again, when you start looking at
Speaker 1: it from a physics perspective, like that's a that's a
Speaker 1: lot of energy that you have to take into consideration.
Speaker 1: And of course that's before anyone that tries to manage
Speaker 1: a triple axel out here. I will not be one
Speaker 1: of those people. I might try my hand at skating,
Speaker 1: but considering my lack of grace just on roller skates,
Speaker 1: I suspect spectacular white belts would be to followed so
Speaker 1: well when they when that ice has finished and ready
Speaker 1: to skate on, you're gonna hear me tap out at
Speaker 1: the other sides and turn it over to another group
Speaker 1: of people to handle it from there on out. You know,
Speaker 1: to your point, the amount of energy and and everything
Speaker 1: that goes into this, you know the I think only
Speaker 1: mother nature really does it better than what we're doing here,
Speaker 1: and it is it is when you start to think
Speaker 1: about the the energy and the physics involved, it is
Speaker 1: h s daunting really sure. Yeah, yeah, And as you
Speaker 1: we were pointing out, just the just taking into consideration
Speaker 1: and how they handle the weight is an enormous undertaking
Speaker 1: because you're on we're on the rooftop of an existing structure. Obviously,
Speaker 1: Uh one, the rooftop was not necessarily intended to hold
Speaker 1: a ton chiller plus a rinkfull of solid water, uh
Speaker 1: not dimensional people on top of it. But that's incidental
Speaker 1: compared to everything else. Uh So yeah, having to take
Speaker 1: that into consideration and look at and how is the
Speaker 1: building built, how does that weight distribute already? Love would
Speaker 1: you need to do in order to offset that in
Speaker 1: any way? If there's a point where you think, well,
Speaker 1: we'd love to play it here, but the roof literally
Speaker 1: can't support it there, There's a lot of things you've
Speaker 1: taken into account, and I imagined the whole process took
Speaker 1: quite some time before anything was laid down at all.
Speaker 1: We we should really started visioning this over a year
Speaker 1: ago and started to kind of analyze the hurdles that
Speaker 1: we would have in front of us, and uh, structural engineering.
Speaker 1: Of course, it was our first consideration, can we handle
Speaker 1: the pounds per square foot up here? What's the rating
Speaker 1: of this ice gonna be? And how well is our
Speaker 1: deck engineered? And and so we had to bring in,
Speaker 1: you know, the brainy acts to help us out and
Speaker 1: figure out exactly what we could handle up here, because
Speaker 1: it's not just ice. We have wind load up here,
Speaker 1: and then we're gonna have a human load as well.
Speaker 1: So if you really start to factor in all of that,
Speaker 1: and the math kicks in. And we were fortunate that
Speaker 1: we have very robust engineering up here and that we
Speaker 1: were able to to pull this off. But uh yeah,
Speaker 1: almost at every turn of the project we were we
Speaker 1: were surprised by the complexity of it and surprised because
Speaker 1: this was a little bit out of our wheelhouse. This
Speaker 1: was a new venture for us, and so the learning
Speaker 1: curve was steep. Well. To me, those are the most
Speaker 1: exciting projects to work on. I've always said that my
Speaker 1: job is one of the best I can imagine because
Speaker 1: I get to learn new things every single week, and
Speaker 1: that you know, that challenge is what I feed off of.
Speaker 1: At times, it can obviously become so challenging as to
Speaker 1: be frustrating, but the fact that we're looking at a
Speaker 1: project that's so close to being ready for the public
Speaker 1: to see. I'm very excited to actually get a look
Speaker 1: at the rink once it's all finished. Being able to
Speaker 1: see that in this state is actually really cool for
Speaker 1: me because it's something that I typically would never have
Speaker 1: been able to see, you know, outside of just images
Speaker 1: or maybe some videos. So having this opportunity is fantastic.
Speaker 1: I really appreciate it, and I can't wait to see
Speaker 1: this chiller I've heard so much about. Well it was.
Speaker 1: It was a beast and and to see it come
Speaker 1: off of a huge flatbed truck and have the crane
Speaker 1: and of course you just don't latch onto it. You
Speaker 1: can imagine, you know, even a five mile an hour
Speaker 1: breeze as you're craning something hundreds of feet into the
Speaker 1: air can get a little bit dicey. So they just
Speaker 1: just watching the crane set up, it's booms and it's
Speaker 1: it's weight distribution. That was a whole another engineering lesson
Speaker 1: in itself. Again, the physics involved in every phase of
Speaker 1: this was really amazing, and and yeah it was. It
Speaker 1: was an enormous amount of fund for me to be
Speaker 1: a part of this, To go through the learning curve
Speaker 1: and I can now speak in in some languages of
Speaker 1: physics that I couldn't have before we started the project.
Speaker 1: You never know, and that's gonna come in handy on
Speaker 1: the future projects. And that's also well, thank you so
Speaker 1: much for showing the rink. I really appreciate it. I'm
Speaker 1: I really can't wait to see this one. It's ways
Speaker 1: ago well as a pleasure having you up here. And uh,
Speaker 1: I think we'll force you to get into a pair
Speaker 1: of skates and get on the ice when we're done.
Speaker 1: I think I have to. At this point, I want
Speaker 1: to thank Mr Brett hole Ride for inviting us up
Speaker 1: and taking a look at the ice rink in progress.
Speaker 1: It was pretty awesome, not just to see the rink
Speaker 1: itself and how it was laid out and with all
Speaker 1: those tubes of glycol underneath, but also just that massive chiller,
Speaker 1: hundred twenty ton chiller on the roof of this building.
Speaker 1: It was enormous, along with the huge pump that was
Speaker 1: necessary to actually move the glycol through the system, and
Speaker 1: we never would have had a chance without it. So
Speaker 1: thank you again, Brett. And I got a little bit
Speaker 1: more to say about maintaining an ice rink. But before
Speaker 1: I go into that last section, let's take another quick
Speaker 1: break to thank our sponsor. Alright, I thought it might
Speaker 1: be fun to end this episode with a look at
Speaker 1: ice resurfaceers. Typically, folks would refer to these as a Zamboni,
Speaker 1: But just to be clear, Zamboni refers to a particular
Speaker 1: brand of ice resurfacing machines. It's just that most folks
Speaker 1: use that brand name to refer to the technology in general,
Speaker 1: much the same way that some people will refer to
Speaker 1: any copy machine as a xerox. Now, the purpose of
Speaker 1: these machines is to repair and polish the surface of
Speaker 1: ice rinks as they experience wear and tear, and it
Speaker 1: does not take very long for metal ice skates to
Speaker 1: carve up that nice, pristine surface of an ice rink.
Speaker 1: And once in a while you need to fix things
Speaker 1: so that they're more attractive and to avoid situations where
Speaker 1: a skater goes topsy turvy after hitting a particularly big
Speaker 1: divot cut out of the surface. Now, in the good
Speaker 1: old days, and by that I mean the awful old days,
Speaker 1: this was all done by hand. People would actually venture
Speaker 1: out onto the skating surface with tools to physically chip
Speaker 1: away at that top layer in order to get as
Speaker 1: smooth as surface as possible. They would use shovels to
Speaker 1: shovel up any of the ice shavings that they created,
Speaker 1: either from skating or just scraping that top layer of ice,
Speaker 1: and they would use water hoses to pour out more
Speaker 1: water to replace the ice lost from the whole process
Speaker 1: as well, and they'd use squeegees and towels to help
Speaker 1: spread the water in a thin layer across the entire
Speaker 1: surface to get that nice shiny appearance and make everything
Speaker 1: clean and beautiful again. And the whole process would take
Speaker 1: several hours of backbreaking work. Then in you have a
Speaker 1: visionary named Frank Zamboni who decided to tackle this problem
Speaker 1: and find a better way to resurface an ice rink.
Speaker 1: He and his brother Lawrence had opened up an ice
Speaker 1: rink in California, Southern California at that and they had
Speaker 1: been using a tractor that was outfitted with a large
Speaker 1: blade to scrape that top layer before manually shoveling up
Speaker 1: all the ice shavings and pouring hot water from a
Speaker 1: hose onto the rink and then squeegeeing it by hand
Speaker 1: across the surface. The whole process, even with the tractor,
Speaker 1: meant that it would take about an hour and a
Speaker 1: half to resurface their ice rink, which was not an
Speaker 1: enormous rink. It was a It was a decent size
Speaker 1: one is bigger than the one that we have upstairs,
Speaker 1: but not the biggest one in the world. And so
Speaker 1: Zamboni thought, there's gotta be a better way to do this.
Speaker 1: His solution was to create a new type of vehicle
Speaker 1: that could do as much of this work as pile
Speaker 1: all by itself. And he worked on this concept for
Speaker 1: nearly a decade and created a truly terrifying Frankenstein's Monster
Speaker 1: of a vehicle out of parts that included stuff like
Speaker 1: there was a cylinder from a plane, there was a
Speaker 1: jeep engine driving the whole thing. There was an oil
Speaker 1: derec chassis. So this invention first debuted in nineteen forty nine,
Speaker 1: it obviously went through lots of different evolutionary processes until
Speaker 1: it was refined into the sleek, sexy vehicle we all
Speaker 1: know and love today. And of course, there's more than
Speaker 1: justice Amboni ice resurfacing machines out there at this time.
Speaker 1: There's all sorts of ones that are out there. But
Speaker 1: here's what a modern ice resurfacing vehicle actually does. So
Speaker 1: underneath the vehicle there's a blade that is positioned inside
Speaker 1: an overall structure that's called the conditioner. This you can
Speaker 1: actually raise and lower underneath the zamboni, so when you're
Speaker 1: just driving it onto the surface of the ice, you
Speaker 1: can raise it up so nothing is dragging, and when
Speaker 1: you're ready to start, you lower the conditioner down and
Speaker 1: then you typically have a control that can put the
Speaker 1: angle of attack for the blade at such so that
Speaker 1: you can cut exactly the amount of ice you want
Speaker 1: off the top surface. For hockey rinks, it's a very
Speaker 1: very thin layer, but other rinks it might be a
Speaker 1: little bit more more severe, depending upon what they're trying
Speaker 1: to do. So the blade is typically somewhere between seventy
Speaker 1: seven to ninety six inches in width, which is about
Speaker 1: a hundreds and it cuts that top layer of the ice,
Speaker 1: the very top layer, removes any protrusions, helps level out
Speaker 1: any big divots. Uh. There are a pair of augers
Speaker 1: that catch all the shavings, the the ice chips or
Speaker 1: the snow and they move it into a snow tank.
Speaker 1: Augers are are essentially large screws, so you rotational force
Speaker 1: to move those shavings around. There's one that's horizontal and
Speaker 1: it ends up pulling all the ice shavings, are really
Speaker 1: pushing all the ice shavings into the center back portion
Speaker 1: of the zamboni. Then there's a vertical auger that lifts
Speaker 1: from that central packed mass and moves it up to
Speaker 1: the snow tank, this waist tank that's typically on the
Speaker 1: front of the zamboni or ice resurfacer, i should say.
Speaker 1: And then typically one of these machines will pour hot
Speaker 1: water onto the ice. Behind this there's maybe it's warm,
Speaker 1: not hot water, and helps level out anything that the
Speaker 1: blade wasn't able to get. There's a squeegee that is
Speaker 1: right behind this hot water that then allows that to
Speaker 1: get sucked back up into the system so that it
Speaker 1: can be recycled. And then there's another hot water emitter
Speaker 1: at the very back of the zamboni just before you
Speaker 1: get to the the extreme rear of the vehicle where
Speaker 1: there's a flap. It's essentially a towel at the very back,
Speaker 1: and so hot water drips out and the towel then
Speaker 1: spreads the hot water against the surface of the ice
Speaker 1: ice free surfacers use hot water instead of cold water
Speaker 1: because the hot water, when it makes contact with the
Speaker 1: ice rink, will start to melt that surface ice just
Speaker 1: slightly before it begins to free freeze into a solid layer.
Speaker 1: If you were to use cold water, cold water freezes
Speaker 1: so quickly that you end up more like very thin
Speaker 1: additional layers on top, and those chip way very easily.
Speaker 1: So if you're doing some sort of fancy ice skating
Speaker 1: or you're doing you know, playing hockey or something, you
Speaker 1: end up getting these big chips that fly up, and
Speaker 1: that typically is not really preferred. So that's why they
Speaker 1: use hot water. It it melts the top surface of
Speaker 1: the ice just a little bit before it all refreezes
Speaker 1: and makes it more of a solid layer of ice. Often, Um,
Speaker 1: you'll have a couple of other elements, like there might
Speaker 1: be another brush. It depends upon the vehicle. Some of
Speaker 1: them run on natural gas, some of them run on
Speaker 1: battery power. Um, if you're looking at a full size
Speaker 1: zamboni with a full tank, these things are heavy. They
Speaker 1: weigh about eleven thousand pounds or four thousand ns. These
Speaker 1: are massive, heavy vehicles. So running across that ice is
Speaker 1: no joke. And they also tend to have a metal
Speaker 1: studs on their tires to give them enough purchase to
Speaker 1: be able to actually move across the ice effectively. And
Speaker 1: according to Car and Driver, operating a zamboni isn't exactly
Speaker 1: like driving a sports car. The report said, quote, visibility
Speaker 1: from the elevated left rear position is poor, the abrupt
Speaker 1: throttle tip in takes some getting used to, and the
Speaker 1: vague steering is totally seventies Cadillac end quote. But it's
Speaker 1: still kind of like to ride on one, though, And
Speaker 1: that's our show about ice rinks. I'm still not likely
Speaker 1: to get on one anytime soon unless I just decide
Speaker 1: that a few nice weeks in traction would be a
Speaker 1: really good vacation. But like many Southerners, I really only
Speaker 1: trust ice if it's in my t That wraps up
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