'Cool in 90 seconds' - the fake portable air conditioners sweeping the internet

- Published
As parts of the UK brace for another hot weekend, online adverts have been appearing for portable air conditioners claiming to be "designed by former Nasa engineers" and able to "cool a room in 90 seconds".
The adverts have emerged on platforms including Facebook and YouTube, but the Advertising Standards Agency (ASA) has now warned the products are often "too good to be true".
YouTuber Stuart Matthews, who bought several devices to test on his Proper DIY channel, told the BBC that despite paying £70 for one machine, it turned out to be "a small, simple fan worth only a few pounds".
The BBC has approached Meta and YouTube for comment.
The ASA told the BBC that some of the adverts it had seen online in recent weeks made exaggerated claims, including that a small device could cool an entire home within minutes or used very little electricity.
It also said the adverts frequently featured fake customer reviews describing dramatic temperature drops or exceptional performance.
The adverts direct shoppers to websites selling the devices, typically for between £70 and £120.
Many of the adverts also appeared to be AI-generated, using visuals such as copper coils and metallic boxes to make the products seem more sophisticated.
The ASA said there were several ways for customers to tell if an advert for a portable air conditioner was likely to be misleading.
It said people should be sceptical of the following:
Promises which sound too good to be true, like claims a small device can chill large rooms
Dramatic backstories about "secret inventions" or "industry breakthroughs"
Poor grammar, spelling mistakes and inconsistent branding
Customer reviews describing dramatic results or reading as though they're too perfect
The watchdog advised consumers who were unsure to research the retailer and check it provided genuine contact details and a business address.
Customers should also look for independent reviews rather than relying solely on testimonials on the seller's website.
It added that anyone concerned about an air conditioner advert could report it via their website, external.
A closer look
Matthews said he bought several of the devices to see whether they performed as advertised.
The civil engineer and content creator said rather than buying something that would bring the temperature of his room down quickly, he found he had instead bought some "cheap components" made using "flawed science".
One advert described the product as a "reverse-engineered aircon unit" featuring "a liquid-compressed cooling cartridge".
Matthews said the device actually contained "a load of cardboard fins that get wet as the water blows past them".
While so-called "swamp coolers" - machines that chill air by evaporating water - do work reasonably well in hot, dry climates, they also increase humidity and so are much less effective in humid places like much of the UK.
They are also not conventional air conditioners, which work by removing heat from a room via an exhaust hose or external unit.
"I really feel for the people that have been sucked into buying some of this rubbish," Matthews said.
The ASA said it was monitoring sites to spot such adverts and issuing an enforcement notice "instructing advertisers to get their ads in order". It also bans adverts found to have breached its rules.
Although the body regulates paid-for adverts on platforms including YouTube and Facebook, it cannot issue fines itself.
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- Published1 day ago
- Published1 day ago
- Published10 June

Facts Only

* Advertisements claimed portable air conditioners could cool a room in 90 seconds.
* Some adverts claimed devices were "designed by former NASA engineers."
* A YouTuber tested one machine and found it to be a small fan worth a few pounds.
* The Advertising Standards Agency warned that some adverts made exaggerated claims about cooling large rooms or low electricity use.
* Advertisements featured fake customer reviews describing dramatic temperature drops.
* Some adverts appeared AI-generated using visuals of copper coils and metallic boxes.
* One device included cardboard fins that got wet when air passed over them.
* "Swamp coolers," which use evaporation, increase humidity and are less effective in humid UK climates.
* The ASA monitored sites, issued enforcement notices, and banned breaching adverts.

Executive Summary

Online advertisements for portable air conditioners claiming rapid cooling and engineering by former NASA staff have drawn warnings from the Advertising Standards Agency regarding exaggerated claims. Test results showed that some advertised devices offered minimal cooling, with one tested unit proving to be a simple fan worth a few pounds. The advertisements often featured highly polished visuals, sometimes appearing AI-generated, and included customer reviews describing performance far exceeding reality. The watchdog advised consumers to be skeptical of promises of cooling large rooms quickly or using very little electricity. Furthermore, the advertising frequently utilized poor grammar or inconsistent branding, directing potential buyers to retail sites selling these devices for between £70 and £120.

Full Take

The pattern observed is the leveraging of perceived high authority—NASA engineering—combined with sensationalized outcomes (90-second cooling) to bypass critical assessment. This functions as a potent form of Authority Game, where complex scientific backing is reduced to superficial branding rather than substantive evidence. The underlying narrative relies on creating an immediate, high-stakes desire for 'miracle' efficiency in a climate context, which exploits the gap between marketing hyperbole and practical physics. The exposure of the actual mechanism—cardboard fins wetting out from water—reveals a deliberate obfuscation of reality behind sophisticated visual rhetoric. This suggests a systemic pattern where sensationalism related to technological advancement is used not to inform, but to create an immediate transaction based on manufactured scarcity and perceived breakthrough. The implication is that consumer agency is undermined when highly evocative, yet baseless, claims are packaged with polished aesthetics and peer-reviewed authority references.

Sentinel — Human

Confidence

The text appears to be a well-sourced journalistic piece that effectively blends regulatory warnings with specific, experiential evidence to critique misleading product advertising.

Signals Detected

Sentence length variance is irregular; strong use of direct anecdotal evidence mixed with regulatory recitation.

The structure flows logically from initial hook (ads) to regulatory action (ASA) to specific debunking (Matthews' experience). The shift in tone feels driven by the narrative arc.

The article successfully weaves quotes from multiple sources (Matthews, ASA) to build a case, avoiding simple verbatim repetition of talking points.

Specific, detailed debunking provided by the expert (Matthews) about the mechanism ('cardboard fins that get wet') suggests firsthand experience rather than pure LLM compilation.

Human Indicators

The inclusion of specific, somewhat messy anecdotal evidence from Stuart Matthews regarding the physical mechanism of the devices (cardboard fins, liquid-compressed cartridge) strongly suggests human observation rather than pure synthetic generation.

The tone transitions naturally between reporting advertising claims and presenting expert/consumer warnings.