The overall Which? test score is made up of the following star ratings, all determined by our rigorous lab tests.
How we test noise
Portable air conditioners are generally noisy, but some are quieter than others. We asses noise levels on each unit’s lowest and highest setting.
How we test ease of use
We test how easy each portable air conditioner is to use, including understanding the instruction manual, getting the machine set up, operating it via the control panel and remote, cleaning the filters, moving it around and draining the water out when needed
How we test time taken to cool room by 10 degrees
You don't want to have to wait all day to feel the effects of an air conditioner, so we time how quickly each one can achieve a 10 degree temperature drop in a room
How we test temperature distribution across the room
Some air conditioners leave a room feeling evenly cool throughout, while others create warmer and cooler patches
How we test energy efficiency
We assess how much energy each portable air conditioner uses to do its job; some are far more energy-efficient than others (though portable air conditioners are generally less energy-efficient than split units)
How we test air flow distribution across the room
Some portable air conditioners distribute their cool air evenly across a room; but some will create a strong breeze in some areas and barely make the air move in other areas
