# How does a stand-alone inside air-conditioner work **URL:** \ **Category:** Factual Questions\ **Created:** [June 27, 2024, 9:31pm UTC](https://boards.straightdope.com/t/how-does-a-stand-alone-inside-air-conditioner-work/1003415 "2024-06-27T21:31:00Z")\ **Posts on this page:** 20\ **Page:** 1
**Author:** ![Coriolanus](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/coriolanus/32/18769_2.png) [@Coriolanus](https://boards.straightdope.com/u/Coriolanus)\ **Post date:** [June 27, 2024, 9:31pm UTC](https://boards.straightdope.com/t/how-does-a-stand-alone-inside-air-conditioner-work/1003415/1 "2024-06-27T21:31:00Z")
I looked at past threads yet those machines had exhaust hoses to let the heat generated by an air compressor out of the room. I’ve reinstalled a Windows 11 machine and of course the opening page for [msn.com](http://msn.com) is full of useful news and information, including an ad for what essentially is a tower fan (no hoses visible) that blows cool air and I think it even operates from rechargeable batteries. I can only think of two ways this can work: You occasionally connect a can of freon or pour ice cubes in. Neither are mentioned or visible in the ad. This is impossible, correct? What kind of device would I get if I buy this? ---
**Author:** ![Beckdawrek](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/beckdawrek/32/3647_2.png) [@Beckdawrek](https://boards.straightdope.com/u/Beckdawrek)\ **Post date:** [June 27, 2024, 9:36pm UTC](https://boards.straightdope.com/t/how-does-a-stand-alone-inside-air-conditioner-work/1003415/2 "2024-06-27T21:36:46Z")
What’s the name brand. I couldn’t see an ad in your link. The towers I’ve seen are just fans. ---
**Author:** ![Quondam\_Mechanic](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/quondam_mechanic/32/3404_2.png) [@Quondam\_Mechanic](https://boards.straightdope.com/u/Quondam_Mechanic)\ **Post date:** [June 27, 2024, 9:37pm UTC](https://boards.straightdope.com/t/how-does-a-stand-alone-inside-air-conditioner-work/1003415/3 "2024-06-27T21:37:49Z")
I’ve seen similar ads. I haven’t investigated, but I think they work by a company taking your money and putting it in their pockets. Either that, or they found a way to violate the second law of thermodynamics. (Or, to be fair, it’s what you suggested: you put something cold in 'em and they run a fan past the cold stuff.) ---
**Author:** ![Johnny\_Bravo](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/johnny_bravo/32/493_2.png) [@Johnny\_Bravo](https://boards.straightdope.com/u/Johnny_Bravo)\ **Post date:** [June 27, 2024, 9:39pm UTC](https://boards.straightdope.com/t/how-does-a-stand-alone-inside-air-conditioner-work/1003415/4 "2024-06-27T21:39:10Z")
They’re usually [swamp coolers.](https://en.wikipedia.org/wiki/Evaporative_cooler) ---
**Author:** ![Lancia](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/lancia/32/17174_2.png) [@Lancia](https://boards.straightdope.com/u/Lancia)\ **Post date:** [June 27, 2024, 9:39pm UTC](https://boards.straightdope.com/t/how-does-a-stand-alone-inside-air-conditioner-work/1003415/5 "2024-06-27T21:39:54Z")
Without seeing the device in question and assuming it isn’t just a fan marketed as a “cooler,” it’s likely a form of swamp cooler: a fan blows air across a membrane that sits in a puddle of water, using capillary action to keep the membrane wet. The user fills the little water reservoir periodically and tells themselves that they spent their money on something that actually works. In reality they don’t work very well if at all. Most of them really are just fans marketed as coolers. ---
**Author:** ![Beckdawrek](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/beckdawrek/32/3647_2.png) [@Beckdawrek](https://boards.straightdope.com/u/Beckdawrek)\ **Post date:** [June 27, 2024, 9:40pm UTC](https://boards.straightdope.com/t/how-does-a-stand-alone-inside-air-conditioner-work/1003415/6 "2024-06-27T21:40:26Z")
You have to have a lisc. and loads of bucks to install cans of Freon. ---
**Author:** ![thelurkinghorror](https://avatars.discourse-cdn.com/v4/letter/t/7c8e57/32.png) [@thelurkinghorror](https://boards.straightdope.com/u/thelurkinghorror)\ **Post date:** [June 27, 2024, 9:42pm UTC](https://boards.straightdope.com/t/how-does-a-stand-alone-inside-air-conditioner-work/1003415/7 "2024-06-27T21:42:23Z")
[In this house we obey the laws of thermodynamics!](https://www.youtube.com/watch?v=tuxbMfKO9Pg) Maybe a swamp cooler? You should really exhaust one, but if you’re in a low humidity environment and especially if you don’t mind the room muggy they work through evaporative cooling. ---
**Author:** ![Coriolanus](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/coriolanus/32/18769_2.png) [@Coriolanus](https://boards.straightdope.com/u/Coriolanus)\ **Post date:** [June 27, 2024, 9:53pm UTC](https://boards.straightdope.com/t/how-does-a-stand-alone-inside-air-conditioner-work/1003415/8 "2024-06-27T21:53:55Z")
> [@thelurkinghorror](#): > > In this house we obey the laws of thermodynamics! LOL. Thanks and thanks to all. BTW, after waiting for the add to show in a carousel in MSN,con if seems name brand “Outfany” and it’s on my mini Aerfaro computer and I can’t find a link. I’m sure no one was expecting Kenmore or Carrier. I have used the ice cube “trick” behind my little USB turbo fan. Not yet hooked up Freon. So it’s bunk. On [MSN.com](http://MSN.com). Tsk tsk. ---
**Author:** ![Dewey\_Finn](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/dewey_finn/32/4222_2.png) [@Dewey\_Finn](https://boards.straightdope.com/u/Dewey_Finn)\ **Post date:** [June 27, 2024, 10:00pm UTC](https://boards.straightdope.com/t/how-does-a-stand-alone-inside-air-conditioner-work/1003415/9 "2024-06-27T22:00:31Z")
Are you thinking of [mini-split](https://en.wikipedia.org/wiki/Air_conditioning#Mini-split_and_multi-split_systems) or ductless systems? ---
**Author:** ![WildaBeast](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/wildabeast/32/6_2.png) [@WildaBeast](https://boards.straightdope.com/u/WildaBeast)\ **Post date:** [June 27, 2024, 10:01pm UTC](https://boards.straightdope.com/t/how-does-a-stand-alone-inside-air-conditioner-work/1003415/10 "2024-06-27T22:01:48Z")
The YouTube channel Technology Connections has a good video explaining these devices: [![](https://img.youtube.com/vi/2horH-IeurA/maxresdefault.jpg "Personal "air conditioners" aren't what they seem") ](https://www.youtube.com/watch?v=2horH-IeurA) ---
**Author:** ![Coriolanus](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/coriolanus/32/18769_2.png) [@Coriolanus](https://boards.straightdope.com/u/Coriolanus)\ **Post date:** [June 27, 2024, 10:24pm UTC](https://boards.straightdope.com/t/how-does-a-stand-alone-inside-air-conditioner-work/1003415/11 "2024-06-27T22:24:53Z")
I reckon **WildaBeast** ’s video and the **lurkinghorror** ’s Homer Simpson quote are the answer. Cans of freon can still be purchased - maybe it was just my R-235 that was messing up the Ozone layer and taken off the market. Ice is generally available, imported with great cost and occasional loss of life from the arctic (Simpsons ref). ---
**Author:** ![kenobi\_65](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/kenobi_65/32/13178_2.png) [@kenobi\_65](https://boards.straightdope.com/u/kenobi_65)\ **Post date:** [June 27, 2024, 10:27pm UTC](https://boards.straightdope.com/t/how-does-a-stand-alone-inside-air-conditioner-work/1003415/12 "2024-06-27T22:27:55Z")
> [@thelurkinghorror](#): > > Maybe a swamp cooler? You should really exhaust one, but if you’re in a low humidity environment and especially if you don’t mind the room muggy they work through evaporative cooling. This, exactly. A swamp cooler can help if you live in a hot-and-dry environment, but if your heat is accompanied by humidity, one of those inexpensive, battery-operated “mini” air conditioners will just make things feel _more_ uncomfortable, because they’ll be adding more humidity to the air in the room, without actually cooling it off. ---
**Author:** ![Quondam\_Mechanic](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/quondam_mechanic/32/3404_2.png) [@Quondam\_Mechanic](https://boards.straightdope.com/u/Quondam_Mechanic)\ **Post date:** [June 27, 2024, 11:11pm UTC](https://boards.straightdope.com/t/how-does-a-stand-alone-inside-air-conditioner-work/1003415/13 "2024-06-27T23:11:46Z")
> [@Dewey\_Finn](#): > > Are you thinking of [mini-split](https://en.wikipedia.org/wiki/Air_conditioning#Mini-split_and_multi-split_systems) or ductless systems? No, those are normal A/C’s. They just cool a liquid that goes to the different rooms instead of moving cool air around via ducts. ---
**Author:** ![Dewey\_Finn](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/dewey_finn/32/4222_2.png) [@Dewey\_Finn](https://boards.straightdope.com/u/Dewey_Finn)\ **Post date:** [June 27, 2024, 11:27pm UTC](https://boards.straightdope.com/t/how-does-a-stand-alone-inside-air-conditioner-work/1003415/14 "2024-06-27T23:27:18Z")
I thought perhaps the OP missed the pipes leading to the outside compressor and assumed the inside components were the entirety of the mini-split system. ---
**Author:** ![ParallelLines](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/parallellines/32/3575_2.png) [@ParallelLines](https://boards.straightdope.com/u/ParallelLines)\ **Post date:** [June 27, 2024, 11:47pm UTC](https://boards.straightdope.com/t/how-does-a-stand-alone-inside-air-conditioner-work/1003415/15 "2024-06-27T23:47:29Z")
See also this thread: > [@Chillwell A/C units. Do they work or is it a scam?](https://boards.straightdope.com/t/chillwell-a-c-units-do-they-work-or-is-it-a-scam/966272/2): > > Based on everything I’ve seen about them, it’s not . . . totally a scam. What it seems to be is a micro [swamp cooler](https://home.howstuffworks.com/home-improvement/heating-and-cooling/swamp-cooler.htm), like maybe, one smallish rooms worth. If a swamp cooler works with your climate, then, yeah, it would cool you a bit. Especially for the brief time you add ice to the unit. If your climate is humid, or the temps are high enough, nope, does nothing more than a multi-speed fan would. But for the small coverage area, they seem quite expensive, so I’m leaning towards over-hyped … Which references this one as well: > [@Are these advertised products frauds?](https://boards.straightdope.com/t/are-these-advertised-products-frauds/988306): > > Are these frauds? Or are they genuine and I’m missing something? I’ve seen all of these products advertised on YouTube videos. Some are available on Amazon, eBay, and Lowe’s. Why hasn’t the FTC sued these companies for fraud. The first product is a mini “air conditioner” about the size of a toaster. It advertises to cool a room in minutes. You can save $$$ with this device. BS: It’s not an air conditioner; it’s a small humidifier. How it works: It has a 660ml reservoir for you to put t… But yeah, “no installation/venting/outside access required” are almost always underpowered swamp coolers (sometimes with ice added), standing fans with woo, or out and out frauds. Yes, I know the OP is referencing a tower, not the mini-mini variants, but same technology (or lack of) almost all the time. At least with a tower, you’ve got a bigger fan! ETA - of course, if it’s the same/similar to this: > **[Amazon.com: Outfany Portable Air Conditioner, Shirem Cooling Ace, Outfany...](https://www.amazon.com/Outfany-Portable-Conditioner-charging-Bladeless/dp/B0D6W9PR1G)** > > Specification: Name:Outfany Portable Air Conditioner Colors: Gray, White Types: USB Rated Current: 2.1A Weight: 588g Size: 9.44x6.69x3.93 in Package Includes: 1 PCS \* Outfany Portable Air Conditioner Note: 1.Due to the lighting effects and shooting... Then it’s calling itself a portable air conditioner when it’s described operation is ONLY of a fan. So, more scammy than usual. ---
**Author:** ![DrDeth](https://avatars.discourse-cdn.com/v4/letter/d/b487fb/32.png) [@DrDeth](https://boards.straightdope.com/u/DrDeth)\ **Post date:** [June 28, 2024, 1:18am UTC](https://boards.straightdope.com/t/how-does-a-stand-alone-inside-air-conditioner-work/1003415/16 "2024-06-28T01:18:57Z")
Swamp coolers or totally indoor Air conditioners cant cool a room- the laws of Thermodynamics say so. A true portable AC has to have a hose leading outside to vent out the heat. ---
**Author:** ![Coriolanus](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/coriolanus/32/18769_2.png) [@Coriolanus](https://boards.straightdope.com/u/Coriolanus)\ **Post date:** [June 28, 2024, 4:12am UTC](https://boards.straightdope.com/t/how-does-a-stand-alone-inside-air-conditioner-work/1003415/17 "2024-06-28T04:12:12Z")
> [@ParallelLines](#): > > ETA - of course, if it’s the same/similar to this: Yes, same brand and look though while usually positioned horizontally to show (in the pics on the left) the wisps of coolness that it won’t be sending out it can stand as a tower. Twice at least in that ad they use the word “cooling” and while [MSN.com](http://MSN.com) perhaps has a lower standard for what they advertise this being on Amazon is wrong. On the same Amazon page in the “Products related to this item” is another item that comes with ice packs. So your freezer (presumably in another room) has expended the heat and this thing will blow cool air. It’s the same idea as me putting a pint glass of ice cubes behind my small USB turbo fan or in front/behind my other little (rechargeable!) USB fan. ---
**Author:** ![Coriolanus](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/coriolanus/32/18769_2.png) [@Coriolanus](https://boards.straightdope.com/u/Coriolanus)\ **Post date:** [June 28, 2024, 6:07am UTC](https://boards.straightdope.com/t/how-does-a-stand-alone-inside-air-conditioner-work/1003415/18 "2024-06-28T06:07:09Z")
I found what in every way pictured was the same device on eBay for £2.49 compared to the Amazon one at £40 (which was the same one on [msn.com](http://msn.com) for I don’t recall how much) Unfortunately, both colours sold out. ---
**Author:** ![Whack-a-Mole](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/whack-a-mole/32/141_2.png) [@Whack-a-Mole](https://boards.straightdope.com/u/Whack-a-Mole)\ **Post date:** [June 28, 2024, 6:10am UTC](https://boards.straightdope.com/t/how-does-a-stand-alone-inside-air-conditioner-work/1003415/19 "2024-06-28T06:10:36Z")
> [@Lancia](#): > > Without seeing the device in question and assuming it isn’t just a fan marketed as a “cooler,” it’s likely a form of swamp cooler: a fan blows air across a membrane that sits in a puddle of water, using capillary action to keep the membrane wet. That’s exactly what [my humidifier is.](https://www.honeywellstore.com/store/products/germ-free-cool-mist-humidifier-hcm-350.htm) Exactly. ---
**Author:** ![bump](https://avatars.discourse-cdn.com/v4/letter/b/7c8e57/32.png) [@bump](https://boards.straightdope.com/u/bump)\ **Post date:** [June 28, 2024, 2:33pm UTC](https://boards.straightdope.com/t/how-does-a-stand-alone-inside-air-conditioner-work/1003415/20 "2024-06-28T14:33:23Z")
Right- traditional air conditioners actually _move_ heat from inside to outside via the refrigeration cycle. It’s a cool property of the way refrigerants work that they can basically take heat from the inside of the building/refrigerator, move it, and discharge it to the outside air. The most salient point is that you have to have an “inside” and an “outside” to make it work. If you ran a window unit in the middle of your living room, it would blow hot air in one direction, and hot air in the other, and the net gain will be zero, outside of whatever heat the compressor and fan motors create. What they could be doing is using a Peltier cooler to generate cold air and blowing it at you, while letting the hot side discharge somewhere else. That would correspond to the size of the thing, and would _seem_ to be cooling things, even though it doesn’t really do so on a larger scale. I’ve got a dehumidifier that works that way- it basically just uses the Peltier element to condense water, but a byproduct is that the vented air often feels a little cooler than the ambient air, probably due to a mix of not discharging the hot air through the same ducts and the dehumidification. But there’s not a _net_ cooling effect going on. [Next page](https://boards.straightdope.com/t/how-does-a-stand-alone-inside-air-conditioner-work/1003415.md?page=2)