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.