Understanding Ice and Air Conditioning

Ice is a pretty interesting thing. We used to cool with ice. If we take a fan and blow a fan across an ice cube, we're going to have heat transfer. Here I have weighed in a pound of ice. This is a pound of ice right here. So if I had a block of ice, it was one pound. and I push air across it, the temperature there will be warmer than the ice. The ice will be about 32 degrees Fahrenheit until it all melts. So if I'm moving air across this ice, the heat from the air is going to go to the cooler ice, and we're going to have heat transfer. So let's say, just throwing some numbers out, let's say the air was 70 degrees, goes across the ice, some of this ice is going to melt. The air coming out, let's just throw a number out, we'll say 50 degrees Fahrenheit. Where did the heat from the fifty degrees to the seven degrees, seventy degrees, sorry, from seventy degrees to fifty degrees, where did the heat go? The heat went into the ice. But the ice stays at thirty-two degrees. However, some of that ice melts in the liquid. Eventually, we're going to put so much heat across that, all of this ice will melt. So how much heat does it take to melt one pound of ice? Here I have a pound of ice, and if I was going to add heat to this, it would take 144 BTUs of heat energy to melt that one pound of ice. So it takes 144 BTUs of heat energy to melt that one pound of ice. So we actually used the coolest way to get ice, we put a fan, we put a fan across it, as the heat from the air went to the cooler ice, it would cool the air off, and it would cause the ice to melt, latent heat. After all of this, I can't change the temperature of this, it'll be 32 degrees until every last drop of this ice is gone. Once all of this ice is gone, then the temperature of the ice and water will increase above 32 degrees. But all of that has to melt first. John Gorey was a physician back in Florida. And John Gorey, his goal was to have a hospital and help people. And he did. And one of the things that John Gorey learned was that if he had people cooler, they responded better to treatment. So what John Gorey did was had fans, moving fans across ice, and that was a great way to cool. What he had a problem with, though, was getting ice in Florida back in the 1800s. So what he had to do was he had to buy ice from shippers. They would sail up to the north, they would get ice from lakes and ponds, or just off of ice cubes floating around, the big icebergs floating around, and they would sail back down and sell the ice. They needed it for food preservation, things like that. But it was very expensive for him just to use that ice to cool people off. So he went back through science, a lot of the science from all the way through Charles Law and Boyle's Law and Gay-Lussac's Law and the Law of Perfect Gases and a lot of the stuff that was invented all through time from all these inventors. He was able to finally build an ice machine where he made his own ice. So the ice machine was invented way before the AC. And what they did was he built the ice machine so he could make his own ice. And he thought, man, this is going to be a great idea. This is going to be exciting. I can make ice, and I can have this. And so what he did is he went to patent it. He said, man, if I can make a machine that makes ice for people, I want to be a millionaire, and then I can worry about making my hospitals and doing my research. It was a great idea. Now, it had some bugs in it, but it was a great idea, a great invention. He found a guy to back him money-wise, but the big people that shipped ice, they didn't like having this competition. So they actually ran a smear campaign against John Gorey, and he actually died in poverty trying to make the ice machine. The guy that backed him ended up dying, and he died in poverty trying to make the ice machine work because the big companies kept him down the whole time. I like to remember John Gorey because he was everything we do now. Imagine having drinks without ice in it. He did so much, and the poor guy died in poverty. I like to remember John Gorey because everything we do is about the ice machine. But he invented the ice machine way before the AC. In the ice machine, it took 144 B2s to melt one pound of ice. So as we go through time, we've got to think, that's hidden heat, that's latent heat. It takes 144 B2s to melt a pound of ice. If you see a lot of videos on YouTube, there'll be a guy with a bucket, and he'll have a bucket and he'll put a fan on it, and he has ice in here. What he does is, usually it's in a milk jug, he blows air into that, and on the other side, the air comes out cooler. And it is, it cools. John Gore, he's been doing that for a long time. It's nothing really new, except after all that water melts, all that ice melts into a water, what are you going to do to it? He says you're going to go over to your freezer So if we go over to our freezer the top box there, and we put that jug back in the freezer The refrigeration cycle is going to take the heat from this fluid here, and it's going to reject it outside through the compressor pressure refrigeration cycle. So it's going to take the heat from this jug and move it into the air. Then they're going to take that bucket, put the ice back in the bucket with a fan on it, take the heat from the air, blow it over the ice. so it cools the air off. And then we're going to take this jug, once all the ice melts, put it back in the freezer. So we're going to then take the heat out of the ice and put it back into the air. And then we're going to take the frozen jug and put it inside and take the heat from the air, put it back into the ice to make it melt. So those really don't do any good for actually cooling a house. You would need a refrigerator capable of making a significant amount of ice to cool with. Great little trip for camping, but you've got to think, where does the heat go? The heat from the air is going in to make the ice. ice melt. If we put that melted ice in the refrigerator, we have to take the heat out of that water to make it refreeze back to ice. To freeze one pound of ice, I have to remove 144 B2s of heat energy from it. So we used to actually buy ice by the tons. So one ton of ice, one ton of ice weighs 2,000 pounds. 2,000 pounds. So if it took a hundred... 144 BTUs to melt 1 pound of ice, how many BTUs would it take to melt 2,000 pounds of ice? So if we do a quick little math here, it should go up to around 288,000. So we got 144 times 2,000. 288,000. So it takes 288,000 BTUs to melt one ton of ice. But that's in a 24 hour period. So every 24 hours... If you had the fan blowing on it, 24 hours, it would absorb 288,000 BTUs of heat energy. So if I wanted to know, I'm sorry, this is for 24 hours. So if I wanted to know in a per hour situation, I take 288,000 and divide that by 24 hours in a day. 288,000 divided by 24 hours in a day comes out to 12. 12,000 BTUs per hour. 12,000 BTUs per hour. This is a very magical number that you should know. For HVAC, this number ties into so much of what we do. 12,000 BTUs per hour is one ton of air conditioning. Today, we still size our air conditioners on tonnage. An average air conditioner is about a three-ton unit. Here we have a three ton air conditioner. That three ton air conditioner has the same capacity to melt three tons of ice in a 24 hour period. So imagine if your air conditioner is a three ton unit. It has the same capacity as you would have somebody deliver to your house 288,000 B2s times three in a 24 hour period, you're melting three tons of ice. Imagine a truck coming out and unloading three tons of ice every day, every 24 hours, they're bringing to you three tons of ice with a fan blowing on it. That is a three ton air conditioner. It's based off of 12,000 BTUs per hour. So when Willis Carey invented the air conditioner, he invented the air conditioner to cool the air and dehumidify the air. But even though we use it in BTUs, we still convert it to tons of cooling. And it goes back to when John Gorey had his ice machine. to 144 BTUs per hour. Now the reason that's really important, a lot of customers are going to ask you, hey, where does a ton of air, why is it called a ton of air conditioner? Is that unit going to weigh three tons? I don't want that three ton unit on my roof. It's going to collapse my roof. No, no, it goes back to when it would take three tons of ice for that same capacity. Why this is important is if I have a 12,000 BTU unit, that equals a one ton system. And if I had 6,000 BTUs, that would equal a one-half ton system. And if I had 18,000 BTU units, that would be a 1.5 ton unit. 24,000 BTUs, that is a two-ton system. 30,000 BTUs. We add another 6. 6, 7, 8, 9, 10. 30,000 BTU systems. That would be a 2.5 ton system. And then we have a 36,000 BTU system. It's a 3 ton system. We add another 6. We have a 42,000 BTU unit. That's a three and a half ton system. And if we end up with 48,000 BTUs, that equals a four ton system. And can you guess what's next? What's next? What's next is a 5 ton system and that is 60,000 BTUs. NOAA didn't make a mistake that time because they don't make a 4.5 ton system. It goes from a half ton to 1 ton all the way up to 4 tons and 4 tons we jump to a 5 ton. From 5 ton we jump to 7.5 ton, 10 ton, 15 ton, etc. But this is how many tons of ice it would take to melt in a 24 hour period and we simply use it in a 12 hour period. 24,000 BTUs, two ton system. A lot of times in the model number of equipment, if you look for 24, 18, 12, 30, 36, 42, 48, 60, a lot of times that's a key sign of what the tonnage is of that system. But it all goes back to John Gorey when he used ice to help cool people off. Tonnage of air conditioning all ties in together. And what's really good about that, What makes it so important with that latent heat is let's think about if we had two ice chests or coolers. Ice chest number one and ice chest number two. Let's say we put in one pound of water. and we put in one pound of ice. During the day, let's say I put in here 100 BTUs of heat energy to this 32 degree water. If I started out at 70 degrees Fahrenheit, 100 BTUs, we would clearly be at 170, which isn't even practical. So let's use a better number. Let's say if I was to increase it, start my day out in the morning, the water was 32 degrees. And I say it's going to heat up to a hot part of the day where the water ended up being 80 degrees. Let's call it for simplicity, 82. So 82 minus 32. That ends up being 6. 6, 7, 8, 9, 10. So quick. So somebody put 50 BTUs of heat energy into that. We started at 32 degrees, I put 50 B2s in during the day, heat's going into the cooler water, the water's going to be 82 degrees. If I have 32 pounds of ice and I put 50 B2s in, it's at 32 degrees, but that's 144 B2s to melt one ton of ice. So we take 144 minus 50. It's still going to be at 32 degrees Fahrenheit. and I still have 94 B2s of heat energy left. So it wouldn't have even melted half of that ice. I would still have ice water. It'd still be at 32 degrees Fahrenheit. Over here, if I just had water at 32 degrees, the temperature of that water would have increased to 82, whereas ice, because it's latent heat, it's hidden heat, I'm putting heat into that, and it went from 32 degrees to 32 degrees. I just lost some of the ice. I have more water than I had ice. After all of that ice melts, I put 144 BTUs into it, then the temperature of that water would start to change. And that's the beauty of ice. That's why we use ice. That's why we still call it tons of air conditioning, but they're really still sized on BTUs per hour. BTUs per hour times 24 hours is how many tons of ice it takes to melt in a 24-hour period. And that is ice completed.

Ice is a pretty interesting thing. We used to cool with ice. If we take a fan and blow a fan across an ice cube, we're going to have heat transfer.

Here I have weighed in a pound of ice. This is a pound of ice right here. So if I had a block of ice, it was one pound.

and I push air across it, the temperature there will be warmer than the ice. The ice will be about 32 degrees Fahrenheit until it all melts. So if I'm moving air across this ice, the heat from the air is going to go to the cooler ice, and we're going to have heat transfer.

So let's say, just throwing some numbers out, let's say the air was 70 degrees, goes across the ice, some of this ice is going to melt. The air coming out, let's just throw a number out, we'll say 50 degrees Fahrenheit. Where did the heat from the fifty degrees to the seven degrees, seventy degrees, sorry, from seventy degrees to fifty degrees, where did the heat go? The heat went into the ice. But the ice stays at thirty-two degrees.

However, some of that ice melts in the liquid. Eventually, we're going to put so much heat across that, all of this ice will melt. So how much heat does it take to melt one pound of ice? Here I have a pound of ice, and if I was going to add heat to this, it would take 144 BTUs of heat energy to melt that one pound of ice. So it takes 144 BTUs of heat energy to melt that one pound of ice.

So we actually used the coolest way to get ice, we put a fan, we put a fan across it, as the heat from the air went to the cooler ice, it would cool the air off, and it would cause the ice to melt, latent heat. After all of this, I can't change the temperature of this, it'll be 32 degrees until every last drop of this ice is gone. Once all of this ice is gone, then the temperature of the ice and water will increase above 32 degrees. But all of that has to melt first. John Gorey was a physician back in Florida.

And John Gorey, his goal was to have a hospital and help people. And he did. And one of the things that John Gorey learned was that if he had people cooler, they responded better to treatment.

So what John Gorey did was had fans, moving fans across ice, and that was a great way to cool. What he had a problem with, though, was getting ice in Florida back in the 1800s. So what he had to do was he had to buy ice from shippers. They would sail up to the north, they would get ice from lakes and ponds, or just off of ice cubes floating around, the big icebergs floating around, and they would sail back down and sell the ice.

They needed it for food preservation, things like that. But it was very expensive for him just to use that ice to cool people off. So he went back through science, a lot of the science from all the way through Charles Law and Boyle's Law and Gay-Lussac's Law and the Law of Perfect Gases and a lot of the stuff that was invented all through time from all these inventors. He was able to finally build an ice machine where he made his own ice.

So the ice machine was invented way before the AC. And what they did was he built the ice machine so he could make his own ice. And he thought, man, this is going to be a great idea. This is going to be exciting.

I can make ice, and I can have this. And so what he did is he went to patent it. He said, man, if I can make a machine that makes ice for people, I want to be a millionaire, and then I can worry about making my hospitals and doing my research. It was a great idea. Now, it had some bugs in it, but it was a great idea, a great invention.

He found a guy to back him money-wise, but the big people that shipped ice, they didn't like having this competition. So they actually ran a smear campaign against John Gorey, and he actually died in poverty trying to make the ice machine. The guy that backed him ended up dying, and he died in poverty trying to make the ice machine work because the big companies kept him down the whole time. I like to remember John Gorey because he was everything we do now.

Imagine having drinks without ice in it. He did so much, and the poor guy died in poverty. I like to remember John Gorey because everything we do is about the ice machine. But he invented the ice machine way before the AC.

In the ice machine, it took 144 B2s to melt one pound of ice. So as we go through time, we've got to think, that's hidden heat, that's latent heat. It takes 144 B2s to melt a pound of ice. If you see a lot of videos on YouTube, there'll be a guy with a bucket, and he'll have a bucket and he'll put a fan on it, and he has ice in here.

What he does is, usually it's in a milk jug, he blows air into that, and on the other side, the air comes out cooler. And it is, it cools. John Gore, he's been doing that for a long time. It's nothing really new, except after all that water melts, all that ice melts into a water, what are you going to do to it?

He says you're going to go over to your freezer So if we go over to our freezer the top box there, and we put that jug back in the freezer The refrigeration cycle is going to take the heat from this fluid here, and it's going to reject it outside through the compressor pressure refrigeration cycle. So it's going to take the heat from this jug and move it into the air. Then they're going to take that bucket, put the ice back in the bucket with a fan on it, take the heat from the air, blow it over the ice. so it cools the air off. And then we're going to take this jug, once all the ice melts, put it back in the freezer.

So we're going to then take the heat out of the ice and put it back into the air. And then we're going to take the frozen jug and put it inside and take the heat from the air, put it back into the ice to make it melt. So those really don't do any good for actually cooling a house. You would need a refrigerator capable of making a significant amount of ice to cool with. Great little trip for camping, but you've got to think, where does the heat go?

The heat from the air is going in to make the ice. ice melt. If we put that melted ice in the refrigerator, we have to take the heat out of that water to make it refreeze back to ice. To freeze one pound of ice, I have to remove 144 B2s of heat energy from it. So we used to actually buy ice by the tons.

So one ton of ice, one ton of ice weighs 2,000 pounds. 2,000 pounds. So if it took a hundred... 144 BTUs to melt 1 pound of ice, how many BTUs would it take to melt 2,000 pounds of ice?

So if we do a quick little math here, it should go up to around 288,000. So we got 144 times 2,000. 288,000. So it takes 288,000 BTUs to melt one ton of ice. But that's in a 24 hour period.

So every 24 hours... If you had the fan blowing on it, 24 hours, it would absorb 288,000 BTUs of heat energy. So if I wanted to know, I'm sorry, this is for 24 hours. So if I wanted to know in a per hour situation, I take 288,000 and divide that by 24 hours in a day.

288,000 divided by 24 hours in a day comes out to 12. 12,000 BTUs per hour. 12,000 BTUs per hour. This is a very magical number that you should know. For HVAC, this number ties into so much of what we do. 12,000 BTUs per hour is one ton of air conditioning.

Today, we still size our air conditioners on tonnage. An average air conditioner is about a three-ton unit. Here we have a three ton air conditioner.

That three ton air conditioner has the same capacity to melt three tons of ice in a 24 hour period. So imagine if your air conditioner is a three ton unit. It has the same capacity as you would have somebody deliver to your house 288,000 B2s times three in a 24 hour period, you're melting three tons of ice. Imagine a truck coming out and unloading three tons of ice every day, every 24 hours, they're bringing to you three tons of ice with a fan blowing on it. That is a three ton air conditioner.

It's based off of 12,000 BTUs per hour. So when Willis Carey invented the air conditioner, he invented the air conditioner to cool the air and dehumidify the air. But even though we use it in BTUs, we still convert it to tons of cooling.

And it goes back to when John Gorey had his ice machine. to 144 BTUs per hour. Now the reason that's really important, a lot of customers are going to ask you, hey, where does a ton of air, why is it called a ton of air conditioner?

Is that unit going to weigh three tons? I don't want that three ton unit on my roof. It's going to collapse my roof.

No, no, it goes back to when it would take three tons of ice for that same capacity. Why this is important is if I have a 12,000 BTU unit, that equals a one ton system. And if I had 6,000 BTUs, that would equal a one-half ton system.

And if I had 18,000 BTU units, that would be a 1.5 ton unit. 24,000 BTUs, that is a two-ton system. 30,000 BTUs.

We add another 6. 6, 7, 8, 9, 10. 30,000 BTU systems. That would be a 2.5 ton system. And then we have a 36,000 BTU system.

It's a 3 ton system. We add another 6. We have a 42,000 BTU unit. That's a three and a half ton system.

And if we end up with 48,000 BTUs, that equals a four ton system. And can you guess what's next? What's next? What's next is a 5 ton system and that is 60,000 BTUs.

NOAA didn't make a mistake that time because they don't make a 4.5 ton system. It goes from a half ton to 1 ton all the way up to 4 tons and 4 tons we jump to a 5 ton. From 5 ton we jump to 7.5 ton, 10 ton, 15 ton, etc.

But this is how many tons of ice it would take to melt in a 24 hour period and we simply use it in a 12 hour period. 24,000 BTUs, two ton system. A lot of times in the model number of equipment, if you look for 24, 18, 12, 30, 36, 42, 48, 60, a lot of times that's a key sign of what the tonnage is of that system. But it all goes back to John Gorey when he used ice to help cool people off. Tonnage of air conditioning all ties in together.

And what's really good about that, What makes it so important with that latent heat is let's think about if we had two ice chests or coolers. Ice chest number one and ice chest number two. Let's say we put in one pound of water. and we put in one pound of ice.

During the day, let's say I put in here 100 BTUs of heat energy to this 32 degree water. If I started out at 70 degrees Fahrenheit, 100 BTUs, we would clearly be at 170, which isn't even practical. So let's use a better number. Let's say if I was to increase it, start my day out in the morning, the water was 32 degrees. And I say it's going to heat up to a hot part of the day where the water ended up being 80 degrees.

Let's call it for simplicity, 82. So 82 minus 32. That ends up being 6. 6, 7, 8, 9, 10. So quick. So somebody put 50 BTUs of heat energy into that. We started at 32 degrees, I put 50 B2s in during the day, heat's going into the cooler water, the water's going to be 82 degrees. If I have 32 pounds of ice and I put 50 B2s in, it's at 32 degrees, but that's 144 B2s to melt one ton of ice.

So we take 144 minus 50. It's still going to be at 32 degrees Fahrenheit. and I still have 94 B2s of heat energy left. So it wouldn't have even melted half of that ice.

I would still have ice water. It'd still be at 32 degrees Fahrenheit. Over here, if I just had water at 32 degrees, the temperature of that water would have increased to 82, whereas ice, because it's latent heat, it's hidden heat, I'm putting heat into that, and it went from 32 degrees to 32 degrees.

I just lost some of the ice. I have more water than I had ice. After all of that ice melts, I put 144 BTUs into it, then the temperature of that water would start to change.

And that's the beauty of ice. That's why we use ice. That's why we still call it tons of air conditioning, but they're really still sized on BTUs per hour. BTUs per hour times 24 hours is how many tons of ice it takes to melt in a 24-hour period. And that is ice completed.

Transcript for:Understanding Ice and Air Conditioning

Transcript for:
Understanding Ice and Air Conditioning