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  • The Internet, French fries, and air conditioningthese are my personal top three human

  • inventions of all time.

  • Okay, let's add indoor plumbing

  • Now I have a basic idea of how the first two things on the list work, but what about the

  • AC?

  • What makes it as awesome as it is?

  • Believe it or not, but you have to thank mosquitoes for the invention of air conditioning, or,

  • at least, its forefather!

  • No one loves them in the 21st century, but back in the 19th those guys were a real nightmare.

  • They carried around different infections, such as malaria.

  • Things were especially bad in swampy areas of Florida.

  • A local physician and inventor Dr. John Gorrie was trying to find a way to drain the swamps,

  • and while he was at it, he got this revolutionary idea in 1841.

  • He realized the problem was literally in the air.

  • So cooling the air could fix it!

  • Dr. Gorrie arranged shipping of buckets of ice from frozen lakes and streams in the North

  • of the country into hospital rooms in Florida.

  • It worked, but was super challenging logistically, so he came up with a new idea.

  • By 1851, he designed an air compressor to make ice out of water.

  • The mechanism was powered by a horse.

  • This is how the concept of air conditioning was born!

  • It does have a lot in common with the ACs of today.

  • Well, at least the basic idea is the same.

  • A few decades later, engineer Willis Carrier was helping a publishing company to stop magazine

  • pages from wrinkling because of humidity.

  • He designed the first electrical air conditioning unit with cooling coils and air filters.

  • He used cold water as a coolant first, and then installed an ammonia compressor in his machine.

  • Carrier realized it was not only good for magazines, but to humidify or dehumidify room air as well.

  • He patented the invention and started his own Carrier Engineering Corporation in 1915.

  • Air conditioning made its first mass public appearance at the St. Louis World's Fair in 1904.

  • The 1,000 people in the auditorium definitely loved the idea of comfort cooling.

  • In the 1920s, it became a basic need for thousands of people that rushed to movie theaters to

  • watch their favorite Hollywood stars on the big screen.

  • They came up with an unusual solution and decided to modify heating systems to send

  • cold air through floor vents.

  • But now the lower levels were freezing and upper levels still felt too hot.

  • It required a few adjustments, but in the end they fixed the issue and Metropolitan

  • Theater in Los Angeles got the first perfect public air conditioning system.

  • It was good enough for public buildings, but still too large and expensive for homes.

  • It took a couple more decades for engineers to design something perfect for private houses.

  • By 1947, they sold 43,000 systems, and now the AC is present

  • in hundreds of millions of homes across the world.

  • Today's air conditioners work on the principles of Carrier's invention but are, of course,

  • more energy efficient, much quieter, have way better diagnostics and controls,

  • electronic sensors and are made of better materials.

  • What they do is transport heat energy from the house outdoors.

  • It changes the temperature inside, makes air more humid and improves its quality.

  • It has 2 basic parts, or units: the outdoor unit and the indoor unit.

  • There are 2 possible scenarios: you can have either a room air conditioner

  • or a central air conditioner.

  • The way they work is basically the same, except if you have central air conditioning, there

  • is just one indoor unit and one outdoor unit.

  • If you have room air conditioning, it's in every room, or the rooms you believe to be

  • of most importance and you decide to spend money on keeping them cool.

  • I will tell you about the central air conditioner type because that's what I have.

  • So, let's go outside to check out the outdoor unit.

  • It differs model to model and brand to brand, but in general it looks like a box with a

  • fan in the rear or the side of your house.

  • In larger apartment or office buildings, these boxes flock together like birds, except they

  • aren't that cute.

  • The outdoor unit consists of a compressor, condenser coil and a fan.

  • Another vital player in this process is the refrigerant.

  • It travels through the whole system, connects the outside unit to the inside unit, and is

  • technically not a detail but a cooling fluid.

  • The heat from the air inside your home mixes with the refrigerant and moves through the

  • compressor and to the outdoor coil.

  • One cool thing about the refrigerant is that it can go from liquid to vapor state.

  • The same refrigerant is used more than oncethe compressor works like a pump that

  • keeps moving it back and forth through the whole system.

  • It gets compressed and then moves through the condenser coil.

  • It's important to squeeze the gas tightly because the higher the pressure,

  • the higher the temperature.

  • It has to be done to make the refrigerant hotter than the air outside.

  • Heat naturally moves from hotter to colder bodies.

  • The outside air gets in the condenser coil through the fan.

  • The hot air from your house disperses into street air.

  • The refrigerant has just successfully done its job.

  • It cools down, turns into gas again and goes back inside and the process continues and

  • goes on and on.

  • So it's clear now what happens outside, but what about the indoor unit?

  • Let's get back into the house and find it.

  • So, there can be an indoor unit in every room of your house, or the ones you need to keep

  • cool, or one unit in the closet or the basement, or somewhere inside your house.

  • To make it work all over the house, there is also a thermostat, and supply and return

  • air vents.

  • The indoor unit itself is a coil box that has the blower motor right here, the evaporator coil,

  • the expansion valve, the circuit board and the filter.

  • When it gets too hot in the room, the thermostat sends an SOS signal to the circuit board.

  • It turns on the blower motor.

  • The hot air from the room is sucked in through the return vents.

  • Then, the air meets the refrigerant.

  • At this stage, the hot air loses its heat and moisture.

  • But because the cooler takes in the heat it becomes so hot it's not ready to meet the

  • evaporator coils yet.

  • The expansion valve helps it blow off some steam and lose some extra pressure.

  • Then the refrigerant goes from liquid to gas and is ready to move over

  • to the ice cold evaporator coils.

  • The cold refrigerant is moving through little tubes that evaporator coil is made of.

  • Now, let's give the refrigerant some time to absorb enough heat from the indoor air.

  • And done, it's ready to move to the compressor, and you know what happens there

  • in the outdoor unit.

  • All this is going on at the same time and in a never-ending cycle.

  • Well, until the thermostat decides the temperature is okay, and shuts it down

  • before it gets hot inside again.

  • Then, it starts over, the heat goes out, and the cold air comes in.

  • It spreads across the house through the supply vents.

  • Each and every detail in the air conditioner is super important, and even if one of them goes off,

  • the whole process will stop.

  • And I deeply hope it won't as it's getting hot in here.

  • So you see air conditioners have gone a long way to become as efficient as they are today.

  • But progress never stops, and scientists are working on new technologies to make the ACs

  • more energy-efficient, eco-friendly and better looking on both the inside and the outside

  • of the house.

  • Hey, didn't that send a chill down your spine?

  • No?

  • okay.

  • Hey, if you learned something new today, then give the video a like

  • and share it with a friend!

  • And here are some other cool videos I think you'll enjoy.

  • Just click to the left or right, and remember, stay on the Bright Side of life!

The Internet, French fries, and air conditioningthese are my personal top three human

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B1 US BRIGHTSIDE air unit air conditioning conditioning compressor

AC Was Invented Because of Mosquitoes

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    Fibby posted on 2019/12/12
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