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You might be seeing a lot of 
Internet Influencer Hype Advertiser Content

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You Won’t Believe They Don’t Want You To See!
 lately about these so-called

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personal air conditioners.

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You might have wondered if these might be
too good to be true.

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And today I’m here to tell you that you’re
right to wonder,

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and the answer to your question is an absolute,

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unequivocal,

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indisputable,

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irrefutable

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probably.

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This thing, as well as most of the devices out there which emulate its design including the Blaux?…

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Blaugh?

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Bloerp?... is a miniature swamp cooler.

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Note; not air conditioner!

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Despite what it
may claim on the box.

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Swamp cooler.

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By the way, swamp cooler seems to be a rather US-specific term;

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evaporative cooler is the more technical and also less gross term.

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But swamp is just one syllable so I’m saying
that.

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It’s also just more fun!

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Swamp.

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Swomp.

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Swawmp.

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See?

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Deal with it.

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Swamp coolers do work, in fact in parts of
the world they’re genuinely wonderful and

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can sometimes negate the need for air conditioning
altogether.

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But these are not replacements for air conditioning.

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If you live in a region of the world where
the role of air conditioning isn’t just to cool,

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but indeed to provide dehumidification,

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well then these thing are just silly!

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You see, these aren’t air conditioners by
any stretch of the imagination.

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However, in a sort of odd twist, swamp coolers
do in fact use the same general sort of principle

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as a conventional air conditioner.

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They exploit the fact that as water evaporates,
it takes energy from the air in order to do so.

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I talked a bit about latent heat in my video
on rice cookers.

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At a very basic level it's simply that in
order for a substance to change phases from

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liquid to gas, it requires a lot of energy.

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Water is, believe it or not, a substance and
you can see this in action when you boil it.

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It doesn’t just disappear when it reaches
boiling point because it takes *more* energy

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to cause it to vaporize.

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The same thing happens when water evaporates.

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You don’t have to get water up to boiling
point in order for it to change phases.

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You probably knew that already, the water
cycle is a thing and we have rain and stuff

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and the oceans aren’t boiling.

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In any body of water, the water molecules
close to the surface can, depending on conditions,

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have enough kinetic energy to free themselves
from the liquid phase fairly easily.

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Of course extra energy, for example from the
sun, will help but the key thing is no matter

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how water changes phases, it takes a little
energy for itself.

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A device like this is simply using that concept
to provide *some* cooling.

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All it is is a fan which blows air past some
sort of absorbent material which holds water.

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The forced airflow and the large surface area
provided by these paper flute things helps

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the water to evaporate quickly.

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As it does so it takes some of the heat energy
in the air with it and the effect is that…

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well you get a bit of cooling.

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This is, by the way, exactly how sweating
cools you off.

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Fun fact!

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The name swamp cooler is thought to have originated
from the musty smell these often develop as

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algae and other fun lifeforms take refuge
in their mightily moist matrices.

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If you’ve never encountered a swamp cooler before, well we’ll get into why that might be in a short while,

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but you’ve probably
experienced the concept at work in one way or another.

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Those misting fans that blow not just air but
also a fine mist of water at you?

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Their goal isn’t just to make you annoyingly
damp,

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in fact the hope is that you don’t get wet at all.

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Instead, the spray nozzles atomize the water
into a very fine mist, which will quickly

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evaporate and cool the air, sometimes a dramatic
amount.

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Even without the fan, if you’ve seen those
mister things in a garden or whatever -

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well typically that's the goal.

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Cooling.

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And that’s the same sort of thing that these
devices do.

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But there’s a big, big, big big big big huuuuge
caveat.

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See, where I live, air conditioning isn’t
there just to make a space cooler.

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It’s also there to remove moisture from
the air.

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In fact that was the original purpose of air
conditioning - to dehumidify the air in factories

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and other industrial buildings where humidity
was causing problems on the production line.

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Human comfort was just a bonus.

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Air conditioners can remove moisture because
the refrigeration cycle relocates heat energy

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via a liquid refrigerant, which creates a
very cold surface which water vapor in the

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air will condense on.

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OK, time to bring this guy out again.

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I’m going to explain what actual air conditioners
do,

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and if you’re not interested in this part go ahead and skip to here.

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But, I think it will help to illustrate why
these fad devices are…

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fad devices.

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This is a basic window air conditioner operating
via the refrigeration cycle.

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This is about as small as they come, but for
larger systems everything just gets scaled up

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and sometimes moved around a bit

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The refrigeration cycle really is almost magical,
so here’s a brief overview.

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For now, the only things we need to focus
on are these pipes.

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Notice that it’s a sealed loop, starting
and ending at the heart of the system,

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the compressor.

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All these various pipes are filled with a special chemical called a refrigerant.

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What’s so special about refrigerants?

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Well, I’ll show you!

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This is a can of R134a

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(also known as 1,1,1,2-tetrafluoroethane).

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It’s typically used in cars but is currently being
phased out.

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Now you obviously can’t feel this through
your screen but this can is clearly filled with a liquid.

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You can shake it and tell that there’s definitely
something sloshing around in there.

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Maybe you can hear it.

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[sloshy liquidy sounds]

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Put it on a scale and you can see that it
weighs what it says it does plus the can.

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But here’s the key thing - this would really
prefer to not be a liquid right now.

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The boiling point of this chemical is -15° Fahrenheit,
 or -26°C

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That’s really cold!

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So why is it still a liquid?

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It’s at room temperature but also not a gas.

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How?

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Well, because it’s trapped in this can.

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It’s under pressure, and when you confine
a gas into a small space

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(and thus increase the pressure it’s under) 
you raise its boiling point.

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Right now, at room temperature, the pressure
in this can is about 70 psi.

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Not tremendously high.

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And so long as it’s in this can, it will
stay a liquid.

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It doesn’t have room to expand into a gas.

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But, if I were to puncture a hole in this
can,

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which I’m not going to do because this chemical is environmentally problematic,

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it would instantly begin boiling once the pressure is relieved.

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And the key is, in order for it to do that,
it has to remove energy from the space it's in.

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The latent heat of vaporization doesn’t
just go away when the refrigerant is at a

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higher temperature than boiling - it still
needs to get energy from some place to change  phases

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- or boil.

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It will initially do that from itself, causing
the liquid to get very cold very quickly,

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but then it will actually pull energy from
its surroundings to keep boiling.

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It becomes an area devoid of heat energy,
so ambient energy will naturally spill into it.

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That makes the air around it get colder.

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But, once it’s all expanded to a gas, we’ve achieved
equilibrium and the energy transfer stops.

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The single most important property of refrigerants is
that they don’t need to be under very high pressures

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in order for us to raise their boiling
point above ambient temperature.

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This can really isn't that strong at all
and yet it’s able to keep the refrigerant a liquid.

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In fact, fun fact!

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Those cans of computer duster you can buy?

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Those are filled with a refrigerant.

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If you thought that was just compressed air

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Nope! It’s a refrigerant.

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You need very strong tanks to hold back compressed
air.

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Just look at this little three gallon air
compressor.

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This tank is made of thick steel and when
charged to its max of 110 PSI,

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it barely holds enough air to fill a tire.

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Because selling a can of compressed air would
require expensive steel cans

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that can accomplish hardly any dusting work,

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these cans are filled with a liquid refrigerant which expands into a gas as it is vented by the spray nozzle.

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[ffffssssssstttt]

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This allows for much more dusting to occur.

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And is precisely why these cans get
cold as you use them!

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It’s a refrigerant briefly refrigerating.

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If you spray them upside down you’ll release
liquid refrigerant

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and you can witness it boil away with your very eyes.

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[phwwwwwoooooosssshhh]

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A slightly terrifying thing about these is
that many refrigerants are terribly potent

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greenhouse gases, and the idea that we just
sell cans of the stuff with the express intent

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of venting directly to the atmosphere is more than
slightly unsettling.

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This particular can is full of R152a, 
or 1,1-Difluoroethane.

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Now, as far as refrigerants go, it’s not
*that* bad.

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It has a global warming potential of 140,

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which sounds pretty bad but it's about
about an order of magnitude less than R134a,

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and also its atmospheric lifetime is only
slightly more than a year

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(again, about an order of magnitude better than this).

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So, in all likelihood it’s probably not that bad.

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Still, I would highly encourage you to look
up what refrigerant is used in your preferred duster

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(if you have one)

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or better yet find alternative means of dusting your computer junk.

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And by the way, this very same chemical is
often used as a propellant in products like

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spray paint and hair spray, and we used to
use good ‘ol R-12,

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everyone’s least favorite ozone-depleting chlorofluorocarbon (CFC)

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trade named Freon for that task.

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Yeah, the ozone layer still hasn’t forgiven
us for that one.

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But anyway, because you don’t need terribly
high pressures to hold refrigerants in liquid form,

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we can easily build a machine which
will force it to condense and evaporate

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when and where we want it to.

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And that’s what an air conditioner or refrigerator
does.

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The compressor, which by the way is the same
sort of thing as any old air compressor

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but it’s sealed in this black cylinder so that
it’s surrounded by refrigerant and also doesn’t leak,

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squeezes it into the confined space
of this first heat exchanger known as the condenser.

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That causes it to get quite hot but more importantly
increases its boiling point dramatically

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as pressure in the condenser builds.

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With the aid of these fins and a fan forcing
air through them,

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it will get cooled back down as it travels through the pipes.

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By the time it’s at the end, it has condensed
into a liquid.

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Let’s take a look at that with a thermal
camera.

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This has been off overnight so everything
is close to room temperature.

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It’s amazing how quickly the condenser heats
up, and also how uniformly.

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Almost instantly the pressure is high enough
for some of the refrigerant to start condensing

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on the inner walls of the pipes.

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And just as an evaporating refrigerant steals
energy from its surroundings to boil,

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a condensing refrigerant releases energy as it becomes
liquid again.

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That’s why the condenser gets hot - the
refrigerant is releasing a ton of heat energy

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as it changes phases.

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Liquid refrigerant will eventually start to
build up at the end of the condenser,

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and it will usually be cooled down a little further

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(which, incidentally, is called subcooling in HVAC parlance)

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before it reaches the metering device.

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This ensures a decent volume of liquid refrigerant is at the metering device in preparation for the next step,

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and is precisely why the amount
of refrigerant inside any given refrigeration system,

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known as the charge, is so critical
for proper function.

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The restriction created by the metering device
facilitates a dramatic pressure imbalance

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between the two sides of the system, because
just as the compressor is creating high pressure

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on its output side, its input side creates
suction and thus low pressure.

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The metering device can be as simple as a
capillary tube which restricts the volume

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of refrigerant that can pass through it, or
it can be as complex as a thermal expansion valve

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which reacts to changes in thermal load
to ensure optimal refrigeration performance.

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That’s deeper than we need to be going, but once
liquid refrigerant passes into the next chamber,

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another heat exchanger called the
evaporator, its boiling point plummets.

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Now that it’s in a low pressure environment,
it starts to boil just like the refrigerant

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you release from a can of computer duster.

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And it needs energy in order to do that, so
it takes it from the air around the evaporator,

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making it get very cold.

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Again, let’s take a look with a thermal
camera.

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As soon as it’s switched on, the evaporator
becomes a sink of coldness,

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a place where energy in the room will naturally go.

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The refrigerant in here NEEDS energy to evaporate,
and it MUST evaporate because the pressure

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is too low for it to remain a liquid.

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The fins of the evaporator help it to scavenge
energy from the air, which ends up cooling the room.

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Once the refrigerant has reached the end,

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assuming the charge is correct, it will have absorbed all the energy it can.

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It will then re-enter the compressor and the cycle
repeats.

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Now the energy it just picked up from inside the room can be expelled in the condenser.

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The conditioning part of air conditioning
happens thanks to the fact that the evaporator

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gets very cold.

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Moisture in the air will condense on cold
surfaces.

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You’ve seen that before when holding a glass of ice water on a humid day.

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That happens because air’s ability to hold
moisture is dependent on its temperature.

223
00:13:26,840 --> 00:13:30,480
Drop the temperature and it can’t hold as
much water, so the water that it’s in it

224
00:13:30,480 --> 00:13:34,080
condenses out of it and onto the cold surface
of the glass.

225
00:13:34,080 --> 00:13:34,940
Fun fact!

226
00:13:34,940 --> 00:13:38,280
That’s how clouds and storms and dew happen.

227
00:13:38,560 --> 00:13:42,140
Because the evaporator gets so cold and air rushes through its fins,

228
00:13:42,140 --> 00:13:48,140
that air will lose its ability to hold moisture so it loses its
water and the evaporator will get very wet

229
00:13:48,140 --> 00:13:49,660
as time goes on.

230
00:13:49,660 --> 00:13:54,760
Thanks to surface tension and gravity, that
collected water (called condensate) will travel

231
00:13:54,770 --> 00:13:59,470
down the fins into either some sort of drip
pan or in the case of many window units simply

232
00:13:59,470 --> 00:14:03,160
the bottom of the machine where it can seep to the
outside.

233
00:14:03,160 --> 00:14:08,540
Newer models like this will intentionally collect it around the condenser, and the condenser fan’s blade

234
00:14:08,540 --> 00:14:11,720
(or even, as is the case here,
a specialized component of it)

235
00:14:11,720 --> 00:14:17,040
splashes water onto the condenser, increasing the efficiency and effectiveness of the air conditioner

236
00:14:17,040 --> 00:14:20,360
through, somewhat ironically, evaporative cooling.

237
00:14:20,360 --> 00:14:26,420
In fact, in this one, the condenser is actually
shaped so that part of it sits in collected condensate.

238
00:14:26,420 --> 00:14:30,900
And it’s done quite cleverly at the very
end of the condenser's loop.

239
00:14:30,900 --> 00:14:35,300
The refrigerant should at this point already
be liquid and piling up at the metering device,

240
00:14:35,300 --> 00:14:39,440
but the water will cool it further making
doubly sure this actually happens and also

241
00:14:39,440 --> 00:14:43,690
increasing subcooling, again that’s the
amount the refrigerant is able cool further

242
00:14:43,690 --> 00:14:45,540
after it has condensed.

243
00:14:45,540 --> 00:14:50,440
That increases efficiency and effectiveness
by allowing the evaporator to absorb a little

244
00:14:50,440 --> 00:14:53,460
more energy after the refrigerant boils.

245
00:14:53,460 --> 00:14:58,320
Remember that when it boils it first takes
energy from itself, so in general the

246
00:14:58,320 --> 00:15:02,100
cooler you can make it before it re-enters
the evaporator the better

247
00:15:02,100 --> 00:15:04,000
(though there is some nuance there).

248
00:15:04,000 --> 00:15:08,140
Some people claim that this practice reduces
the life of the condenser through promotion

249
00:15:08,140 --> 00:15:12,180
of corrosion but those are just some people
who didn’t engineer the thing.

250
00:15:12,180 --> 00:15:17,100
Also, the evaporator which is exactly the
same sort of thing, made of the same materials

251
00:15:17,100 --> 00:15:21,320
and everything, gets wet constantly as it
operates but I digress.

252
00:15:21,320 --> 00:15:25,160
So here’s the key thing - the refrigerant
in here is trapped

253
00:15:25,160 --> 00:15:27,520
and is making a continuous circuit.

254
00:15:27,520 --> 00:15:32,540
We’re forcing it to boil, then condense, boil,
condense, boil, condense, boil and condense

255
00:15:32,540 --> 00:15:34,860
over and over and over and over and over again.

256
00:15:34,860 --> 00:15:35,940
And over again.

257
00:15:35,980 --> 00:15:40,280
And most importantly, we control where those
two things happen.

258
00:15:40,280 --> 00:15:43,400
We’re using the properties of latent heat
to our advantage,

259
00:15:43,400 --> 00:15:46,040
in a deliberate and controlled way.

260
00:15:46,040 --> 00:15:48,060
We call this a heat pump.

261
00:15:48,060 --> 00:15:51,860
With it we can collect and concentrate heat
energy in one location,

262
00:15:51,860 --> 00:15:54,620
and move it to another to be released.

263
00:15:54,620 --> 00:15:58,280
In one direction this will cool a room by
moving heat to outside,

264
00:15:58,280 --> 00:16:02,020
but the cycle can be reversed, which is becoming increasingly common.

265
00:16:02,020 --> 00:16:05,900
Since the refrigerant is actually performing
the work when it changes phases,

266
00:16:05,900 --> 00:16:11,340
it can move four or five times as much energy as the heat pump consumes in the compressor

267
00:16:11,340 --> 00:16:12,750
(depending on conditions).

268
00:16:12,750 --> 00:16:17,660
It’s the closest thing we have to free energy,
and is very neat.

269
00:16:17,660 --> 00:16:22,860
Every real air conditioner, even the terrible
single-hose portable air conditioners

270
00:16:22,860 --> 00:16:26,460
which you should avoid at all costs as I explained here

271
00:16:26,460 --> 00:16:29,840
(feel free to skip around that video as we’re covering some of the same things again)

272
00:16:29,840 --> 00:16:33,330
has a hot side and a cold side.

273
00:16:33,330 --> 00:16:37,380
The cold side collects energy, and the hot
side releases it.

274
00:16:37,380 --> 00:16:42,820
Move energy out of a space and you cool it,
move it into the space and you heat it.

275
00:16:43,200 --> 00:16:46,960
This thing, though… you’ll find no sides
at all.

276
00:16:46,960 --> 00:16:51,920
It’s basically just a wet sponge and a fan
which presents two giant flaws.

277
00:16:51,920 --> 00:16:54,760
The first is that there’s no self-contained
loop.

278
00:16:54,760 --> 00:17:00,660
While you most certainly can use water to
cool air, once it evaporates you need to add more.

279
00:17:00,660 --> 00:17:02,680
Water generally isn’t scarce

280
00:17:02,680 --> 00:17:04,260
(except for where it is)

281
00:17:04,260 --> 00:17:08,760
so for the most part this is more of an annoyance than anything else but it is noteworthy.

282
00:17:08,760 --> 00:17:10,100
And the second flaw?

283
00:17:10,100 --> 00:17:12,920
Well, now it’s time to answer the question
at hand.

284
00:17:12,920 --> 00:17:14,840
Do these even work?

285
00:17:14,840 --> 00:17:19,120
Well, as a concept these can technically work.

286
00:17:19,120 --> 00:17:23,279
In fact, you can even see a slight cooling
effect going on here in the thermal camera.

287
00:17:23,279 --> 00:17:27,920
I’ll emphasize slight, but honestly it is
pretty interesting how it manages to achieve

288
00:17:27,920 --> 00:17:31,200
cooling with nothing but room-temperature
tap water.

289
00:17:31,200 --> 00:17:36,060
And it was more powerful than I expected,
with the air leaving it being about 2 or 3° F

290
00:17:36,060 --> 00:17:38,120
below ambient temperature.

291
00:17:38,120 --> 00:17:41,320
Yes, my expectations were indeed that low.

292
00:17:41,320 --> 00:17:44,600
But now here comes the gigantic caveat.

293
00:17:44,600 --> 00:17:48,420
The real dealbreaker is that, if you haven’t
figured this out already,

294
00:17:48,420 --> 00:17:53,480
a swamp cooler doesn’t dehumidify - it adds humidity!

295
00:17:53,480 --> 00:17:59,720
In order for a swamp cooler to do anything at all, it has to help water inside it evaporate.

296
00:17:59,720 --> 00:18:02,780
And that makes the ambient humidity go up.

297
00:18:02,780 --> 00:18:06,340
In case you thought, oh, well no big deal,
at least it’s cooler

298
00:18:06,340 --> 00:18:11,040
well here’s the other thing - if the ambient humidity is already high,

299
00:18:11,040 --> 00:18:13,640
then swamp coolers just don’t work.

300
00:18:13,640 --> 00:18:15,040
They can’t work.

301
00:18:15,040 --> 00:18:17,279
It literally becomes impossible.

302
00:18:17,280 --> 00:18:22,440
The air has to be able to take on more moisture
in order for the cooling effect to even happen,

303
00:18:22,440 --> 00:18:26,920
and if you’re at or near the saturation
point well then you’re just SOL.

304
00:18:26,929 --> 00:18:32,660
The air that comes from this feels a bit cooler
than air coming from an ordinary fan but…

305
00:18:32,660 --> 00:18:34,260
not by much.

306
00:18:34,260 --> 00:18:38,380
In this test I pointed the louvers so it was blowing right
on this thermostat

307
00:18:38,380 --> 00:18:40,320
(because apparently I don’t have a thermometer)

308
00:18:40,320 --> 00:18:43,350
so I could get a fairly
accurate temperature reading.

309
00:18:43,350 --> 00:18:46,990
And, well, 64 degrees was the best it could
muster.

310
00:18:46,990 --> 00:18:51,740
That’s down from an ambient temperature
of about 67 maaaaaybe 68.

311
00:18:51,740 --> 00:18:55,080
So at best it produced a 4 degree temperature
drop.

312
00:18:55,080 --> 00:18:57,460
This becomes even more damning when you consider
that

313
00:18:57,460 --> 00:19:00,620
this was in an air conditioned space already!

314
00:19:00,620 --> 00:19:04,260
Relative humidity was about 50% when I tested
this.

315
00:19:04,260 --> 00:19:07,300
Outside, though, it was around 80%.

316
00:19:07,300 --> 00:19:11,460
It flat out would not work if it were my only
source of cooling.

317
00:19:11,460 --> 00:19:16,860
To really drive home how much like air conditioners
these aren't, I used the thermostat again

318
00:19:16,870 --> 00:19:20,769
to see what the air exiting the air conditioner
was and… yeah.

319
00:19:20,769 --> 00:19:22,900
That’s actually cold.

320
00:19:22,900 --> 00:19:26,760
In short, swamp coolers only work up to a
point.

321
00:19:26,770 --> 00:19:31,270
And, because we’re dealing with relative
humidity (which itself affects how hot a given

322
00:19:31,270 --> 00:19:35,100
temperature feels to us) it’s anything but
simple.

323
00:19:35,100 --> 00:19:40,960
As a general rule, a swamp cooler could, assuming
it’s a good one, cool to within a few degrees

324
00:19:40,960 --> 00:19:42,940
of the wet-bulb temperature.

325
00:19:42,940 --> 00:19:45,720
Now, what is the wet-bulb temperature, you ask?

326
00:19:45,720 --> 00:19:50,640
Heh, well annoyingly it is the lowest temperature
that can be achieved through evaporative cooling.

327
00:19:51,260 --> 00:19:52,000
I know.

328
00:19:52,000 --> 00:19:53,269
It describes itself.

329
00:19:53,269 --> 00:19:55,289
Hang on, I’ll try…

330
00:19:55,289 --> 00:19:59,830
Basically, the wet-bulb temperature is what
a thermometer which has its bulb wrapped in

331
00:19:59,830 --> 00:20:02,049
wet cotton or the like will read.

332
00:20:02,049 --> 00:20:06,720
It’s affected by how quickly the water evaporates
from that little cotton ball.

333
00:20:06,720 --> 00:20:11,480
It presents the theoretical minimum temperature an evaporative cooler can hope to obtain,

334
00:20:11,480 --> 00:20:16,169
and as humidity goes up, so does the wet-bulb temperature.

335
00:20:16,169 --> 00:20:20,860
When humidity is 100%, the wet-bulb temperature
is the same as the dry-bulb

336
00:20:20,860 --> 00:20:26,300
(also known as… normal) temperature 
because the air cannot take on more moisture.

337
00:20:26,300 --> 00:20:30,059
Given my sense of humor I’m sure I’ve
been called a dry bulb a few times.

338
00:20:30,060 --> 00:20:36,360
Honestly, all you need to know is that as humidity goes up the ability for these to work goes down.

339
00:20:36,360 --> 00:20:39,500
I mean, that makes sense, given that they’re basically
little humidifiers,

340
00:20:39,500 --> 00:20:43,389
and explains why calling these air conditioners is super dumb.

341
00:20:43,389 --> 00:20:46,240
Now, are they without value?

342
00:20:46,240 --> 00:20:47,620
Well… it depends.

343
00:20:47,620 --> 00:20:52,080
It might be nice to use this on my desk as
a supplement to central air conditioning.

344
00:20:52,080 --> 00:20:53,940
Maybe I could run that a little less.

345
00:20:53,940 --> 00:20:57,880
After all a three degree
temperature drop is definitely noticeable.

346
00:20:57,920 --> 00:21:03,600
But certainly it won’t make a dramatic difference
and it definitely isn’t going to cool the room.

347
00:21:04,060 --> 00:21:08,180
In arid places, swamp coolers work amazingly!

348
00:21:08,180 --> 00:21:12,580
Many people have them to supplement traditional
air conditioning and it dramatically lowers

349
00:21:12,590 --> 00:21:16,070
energy needs (at the expense of increased
water usage).

350
00:21:16,070 --> 00:21:22,240
And, since you typically want a little more
humidity in aird places anyway, they’re a win-win.

351
00:21:22,240 --> 00:21:26,580
Swamp coolers can also help the efficiency
of split air conditioning systems by cooling

352
00:21:26,590 --> 00:21:30,500
the space around the condenser coils and thus
increasing their effectiveness.

353
00:21:30,500 --> 00:21:34,169
Kinda like how this one pools the condensate around the condenser.

354
00:21:34,169 --> 00:21:38,340
You can see this in practice in this video
made by HVACR videos.

355
00:21:38,340 --> 00:21:41,929
You should check out that channel if you want
to see some of the various commercial refrigeration

356
00:21:41,929 --> 00:21:46,509
and air conditioning systems out there up
close, as well as the various ways they fail

357
00:21:46,509 --> 00:21:48,999
and how issues are diagnosed and repaired.

358
00:21:49,000 --> 00:21:51,740
It’s really a great channel for that sort of thing.

359
00:21:51,740 --> 00:21:55,300
But here in the Midwest where humidity can
often be oppressive,

360
00:21:55,300 --> 00:21:59,759
swamp coolers don’t do much and actually just make things worse.

361
00:21:59,759 --> 00:22:04,350
Now, this little thing, to its credit, suggests
that you put ice cubes in it.

362
00:22:04,350 --> 00:22:08,649
Which is, well, somewhat hilarious
because then you’re actually using your

363
00:22:08,649 --> 00:22:11,250
refrigerator to cool you down and you know what?

364
00:22:11,250 --> 00:22:12,580
I approve!

365
00:22:12,580 --> 00:22:14,760
Not in any practical way, of course.

366
00:22:14,760 --> 00:22:16,120
It’s absolutely silly.

367
00:22:16,140 --> 00:22:20,500
Your refrigerator made that ice by pulling energy out
of water and dumping into your kitchen.

368
00:22:20,500 --> 00:22:23,400
But technically it would work at least a ‘lil
bit.

369
00:22:23,400 --> 00:22:28,769
But in general these desktop personal coolers are only sometimes able to do anything at all.

370
00:22:28,769 --> 00:22:32,920
It depends entirely on where you live and
also varies day to day.

371
00:22:32,920 --> 00:22:37,700
Now just because I’m not a total jerk about
these things, I have in fact tested this in a few scenarios.

372
00:22:37,860 --> 00:22:43,600
And while I think that sure, it provides a
cooling effect, it’s not the miracle product

373
00:22:43,600 --> 00:22:48,520
that you HAVE TO BUY that all of the ads out
there are proclaiming them to be.

374
00:22:48,520 --> 00:22:53,020
And how on Earth this little thing managed
to get all these five star reviews is …

375
00:22:53,020 --> 00:22:54,760
Suspicious!

376
00:22:54,760 --> 00:22:58,860
And also, right now, these are horribly overpriced!

377
00:22:58,860 --> 00:23:04,480
It is literally a computer case fan, a hunk
of cheap plastic, and a bit of paper

378
00:23:04,480 --> 00:23:06,760
with a tiny control board for everything.

379
00:23:06,760 --> 00:23:11,980
It’s powered over USB and they don’t even
give you the courtesy of providing a power supply.

380
00:23:11,980 --> 00:23:17,720
These should cost no more than $25 and even
then, that’s a lot for what it is.

381
00:23:17,720 --> 00:23:21,340
Plus, the water absorbing material should be
replaced periodically.

382
00:23:21,340 --> 00:23:25,420
It gets gross over time, and do any of these
companies provide replacements?

383
00:23:25,420 --> 00:23:26,980
Who knows!

384
00:23:26,980 --> 00:23:32,260
Keep in mind also that by adding humidity
you’re making your air conditioner work harder.

385
00:23:32,260 --> 00:23:36,440
Getting water to condense removes heat energy
that we can’t feel -

386
00:23:36,440 --> 00:23:38,159
that’s the whole latent heat bit.

387
00:23:38,159 --> 00:23:42,700
So if you have a lot of moisture in the air,
your air conditioner needs to run longer to

388
00:23:42,700 --> 00:23:47,380
provide the same amount of cooling thanks
to all that water that’s condensing on the evaporator.

389
00:23:47,380 --> 00:23:51,800
Using a mini-swamp cooler in an already-humid
place makes your struggling air conditioner

390
00:23:51,800 --> 00:23:56,519
struggle even more (though admittedly, not
much given the small amount of water this

391
00:23:56,519 --> 00:23:58,929
thing is capable of putting out over a day).

392
00:23:58,929 --> 00:24:01,009
So - these things.

393
00:24:01,009 --> 00:24:02,200
Are they a scam?

394
00:24:03,520 --> 00:24:08,620
Well, they just barely pull off a no on a technicality.

395
00:24:08,620 --> 00:24:12,300
I mean, calling it an air conditioner is an
outright lie.

396
00:24:12,300 --> 00:24:20,720
But if they’re sold as “personal cooling devices” then… well yeah I suppose that’s technically true.

397
00:24:20,720 --> 00:24:25,060
But they’re only useful in certain places
and certain situations.

398
00:24:25,060 --> 00:24:29,480
This is not a personal air conditioner, and while
I wish it was as easy as

399
00:24:29,480 --> 00:24:33,540
Just Add Water!
I regret to inform you that it is not.

400
00:24:33,540 --> 00:24:36,880
If you’d like to take a little test drive
of this concept,

401
00:24:36,880 --> 00:24:41,799
I’d suggest you make your own evaporative cooler to see if it would even do anything for you.

402
00:24:41,800 --> 00:24:45,960
You could probably just glue a few kitchen
sponges to a dinner plate in an upright position,

403
00:24:45,960 --> 00:24:47,640
with a bit of space between them,

404
00:24:47,649 --> 00:24:51,160
add some water so the sponges absorb it, and
put that contraption in front of a small

405
00:24:51,160 --> 00:24:56,080
desk fan and get way more cooling than this thing
could ever hope to produce.

406
00:24:56,080 --> 00:25:01,240
Any time you see a cooling device for sale
which doesn’t require either a hose for

407
00:25:01,240 --> 00:25:05,540
exhaust or actual installation, it’s not
an air conditioner.

408
00:25:05,540 --> 00:25:11,420
There has yet to be a device you can just
plop on your desk and actually get air conditioning from.

409
00:25:11,420 --> 00:25:13,340
In fact, that’s impossible.

410
00:25:13,340 --> 00:25:18,960
So while I can’t quite call this a useless
device, it’s alarmingly disingenuous,

411
00:25:18,960 --> 00:25:21,080
terribly overpriced,

412
00:25:21,080 --> 00:25:23,880
and almost always not worth your time.

413
00:25:23,880 --> 00:25:24,880
Thanks for watching!

414
00:25:24,880 --> 00:25:29,760
This is now, I believe, the third time I’ve
explained the refrigeration cycle without

415
00:25:29,769 --> 00:25:33,169
actually making a video specifically about
it.

416
00:25:33,169 --> 00:25:38,340
It really is a remarkable achievement of humanity, and
heat pumps are going to become increasingly

417
00:25:38,340 --> 00:25:42,580
common and important as we move into the age
of electrification.

418
00:25:42,580 --> 00:25:46,590
For sure you’ll be seeing a video about
that before too long, and I think then we’ll

419
00:25:46,590 --> 00:25:50,680
get into the real nitty-gritty like all those
terrible refrigerants we used to use

420
00:25:50,680 --> 00:25:53,580
and how we can move forward with grace.

421
00:25:53,580 --> 00:25:56,420
But for now, le bloops.

422
00:25:57,320 --> 00:25:59,720
♫ disingenuously smooth jazz ♫

423
00:26:01,600 --> 00:26:03,860
But swamp is just one syllabo…

424
00:26:04,740 --> 00:26:06,060
syllabo…

425
00:26:06,060 --> 00:26:07,920
But swamp is just one syllabo…

426
00:26:08,440 --> 00:26:09,679
syllable!

427
00:26:09,679 --> 00:26:11,640
I said “syllabo”... twice now

428
00:26:11,640 --> 00:26:14,480
Now the energy it picked up from cooling the process….

429
00:26:14,480 --> 00:26:17,100
From the cooling process…

430
00:26:17,100 --> 00:26:18,820
uugghghhg

431
00:26:18,820 --> 00:26:19,400
But!

432
00:26:19,409 --> 00:26:21,920
I think it will help to illustrate why these

433
00:26:21,920 --> 00:26:23,780
.... oh I need it here, ha!

434
00:26:24,400 --> 00:26:25,860
In fact, fun fact!

435
00:26:25,860 --> 00:26:28,660
[clink as the nozzle hits the table] 
The… shoot.

436
00:26:28,660 --> 00:26:31,940
And if you’re not interested in this part,
go ahead and skip to here.

437
00:26:31,940 --> 00:26:33,400
But, I think it will help to…

438
00:26:33,400 --> 00:26:35,590
that’s right
in front of my face, that’s a bad idea.

439
00:26:35,590 --> 00:26:40,860
The air that comes from this feels a little
bit cooler than the air coming from an ordinary fan, but

440
00:26:40,860 --> 00:26:41,960
not my much.

441
00:26:41,960 --> 00:26:43,360
Not My much.

442
00:26:43,360 --> 00:26:45,380
It’s not MY much it’s YOUR much!

443
00:26:46,760 --> 00:26:49,480
The way these things are marketed?

444
00:26:49,480 --> 00:26:51,900
Not cool.

445
00:26:51,900 --> 00:26:55,420
Oh I regret not working that into the script somehow.

446
00:26:55,420 --> 00:26:58,880
But now it's the secret end joke, so yay!