ELi5 Why do we out air conditioners in windows?

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I have a portable one that has a hose thing that goes to a window but I don’t understand why it’s necessary. Is it?

In: Technology

11 Answers

Anonymous 0 Comments

What an AC does is basically just removes heat from a room by moving it outside of said room. Less heat means the room feels cold.

If the AC cant move the heat *out* of a room its worse than just not having an AC. Because now it’s not removing the heat but just by running its generating some heat of its own.

Anonymous 0 Comments

Air conditioners blow out both hot and cold air simultaneously.

If you don’t direct the hot air out of the room you’re trying to cool, it’s not going to do a very good job at bringing the temperature down.

Anonymous 0 Comments

Also, this is the worst type of portable AC. I would recommend a window unit, if possible. See [this](https://youtu.be/_-mBeYC2KGc) video for more information as to why they are so bad.

Anonymous 0 Comments

The hose from my air conditioning unit fell out of my window once and I woke up to an unbelievably hot room.

Anonymous 0 Comments

ACs take heat from the air, but that heat has to go somewhere. You probably don’t want it in your room so the most convenient place is out the window

Anonymous 0 Comments

Its notable that ACs do not exchange the indoor/outdoor air, or at least not much of it. It’s actually extracting the heat from the indoor air and dumping it via a radiator to the outside air

Anonymous 0 Comments

Air conditioners don’t really “make” coldness. They actually move hotness from one place to another. The air conditioner’s job is to take some of the hotness in your house and put it outside

Anonymous 0 Comments

ACs work in a similar way to fridges: they use a compressor to sequentially compress and expand gas in a refrigerating coil. The unit sucks in the air in the room, humidity condenses on the coil and accumulates in a tank as liquid. At the same time the AC ejects air previously cooled by the same refrigerating coil.

They need an outlet facing outside because, in order to function, their compressor necessarily generates heat, which must be directed away from the location to refrigerate.

Anonymous 0 Comments

An air conditioner is basically a heat exchanger. It doesn’t ‘make’ cold (heat is energy and cold is just the absence of that energy), so what an air conditioner does is take heat energy from one place and put it somewhere else.

The way air conditioners work is by condensing and evaporating a refrigerant (basically a liquid with a low boiling point)

So, the refrigerant is pumped as a liquid into the ‘cold side’ of the A/C unit where it’s under low pressure which allows the refrigerant to boil off and evaporate. The refrigerant needs energy in order to boil and it gets this by absorbing heat from the environment. This refrigerant is then pumped to to ‘hot side’ of the A/C unit where it is compressed and the high pressure causes the refrigerant to turn back from a gas to a liquid and release the heat it absorbed on the cold side. Then, the now liquid refrigerant is pumped back to the cold side and the whole process starts again.

Basically, liquid boils, absorbing heat from the environment, and then is compressed back to a liquid dumping that heat back into the environment. We’re just moving heat energy from one place to another.

So, basically, if you just put an A/C unit in the middle of the room, it’s going to blow cold air out the front and hot air out the back. It’s removing the heat from the air and just releasing it again.

But, if you put the A/C unit in a window, it’ll take the heat from the air in your room and then release it outside. With your unit, that’s what that hose is for.

Anonymous 0 Comments

A portable air conditioner takes the air from your house, half of it becomes hot and half of it becomes hot. The cold air is vented forward into your room. The hot air must be disposed outside, else your room will never get cold.