DIY air conditioners may seem like a cheap way to beat the heat, but they aren’t perfect. This video puts two homemade versions to the test and compares them to real AC units.

In this video from the Consumer Reports YouTube channel, air conditioning specialist Chris Regan built two homemade AC units that cost around $30 to see how they actually perform. Over the span of an hour, both DIY units were only able to bring the testing room’s temperature down about three degrees. And half an hour of running, the temp began to rise back up. When they tested spot cooling with the DIY units, however, they found the air to be about 15 degrees cooler. So, best case scenario, you have to sit right next to your DIY AC to get any sort of benefit from it. A homemade unit is better than nothing, but you’ll be much better off with a real AC unit that can cool entire rooms and maintain the temperature.

Putting a Homemade Air Conditioner to the Test | YouTube