If you're spending this much on an appliance – and one that's going to take up a good deal of storage space in the home – then you might want it to do more than just cool. No, absolutely not. A mobile air conditioner needs space to allow airflow and air intake. In a small space the device can overheat.

This has the effect of dramatically reducing the temperature in the room. In our tests, we found the best portable air conditioners, used in a well-sealed room, could reduce the temperature by up to 10 degrees in under an hour.

Air coolers are growing increasingly popular, giving you a kind of halfway house between an expensive and bulky air conditioner and an ordinary fan. They can’t refrigerate the air like an air conditioner, but they can reduce the heat through a combination of airflow and evaporation, effectively using some of the thermal energy in the air to evaporate water, so lowering its temperature before it’s driven out through a fan. It also comes with a remote control and two window kits included, a timer function, 'night' mode for (slightly) quieter night-time operation, plus 3-in-1 air con, fan and dehumidifier functionality. R-410A is a cooling agent that is used in appliances that cool up to 0°C, like refrigerators and air conditioners. It is the replacement of older cooling agents and does not damage the ozon layer.

A portable air con unit uses both a fan and a compressor to cool the air, and that's a noisy process, meaning you're likely to have to turn the TV up quite a few notches if you have one running in a living space. And, if you're a light sleeper, then you may struggle to sleep whilst the air con unit is running. We found the the best bet is to run the air con unit in a bedroom for a few hours before you want to go to sleep, and then turn it off once you turn in for the night. Affordable, lightweight and compact, energy efficient and easy to use, there's lots to love about the MeacoCool MS Series. We tested the smallest 7000 BTU model, but there are also 8000, 9000, 10000, 12000, and 14000 BTUoptions for every room size imaginable. As the name suggests, it also has basic smart features. With the cooler connected to your Wi-Fi network, you can control it from your smartphone or even an Alexa or Google Assistant speaker, although the voice commands don’t cover much more than switching modes or turning the unit on and off. After being massively impressed by the brand's virtually silent Duux Whisper Flex Ultimate Fan, we had high hopes this unit was going to be just as whisper-quiet, but sadly that also wasn't to be, with the North Smart proving just as loud as your average portable air con.Like most portable air con units of this power, it isn't light, weighing in at 27kgs, and its most common negative gripe from users is – as with most air con units – its noise. On its lowest, night-time setting the manufacturer advises it produces 53dB of noise. Interestingly, figures aren't given for decibel levels on the highest fan speeds, suggesting they climb quite a lot higher as you scroll upwards through its two additional speed settings. In terms of cooling powers this is one of the most powerful portable air con units we've tested, but, that power does comes at a price, with the AEG Comfort 6000 using 3400W of energy compared to the MeacoCool MC Series 7000BTU units 780W. It means running costs for the AEG are higher – as is the initial outlay compared to the Meaco – but, our reviewer did find they didn't need this unit running for as long to cool down a space. It has some downsides, but only in keeping with most portable air con units, in that it's heavy which makes it not quite as portable in reality as its name may suggest.However, the build quality is good, it has easy-to-use controls, and its design is unobtrusive – although we think the AEG Comfort just pips it to the post in the style stakes by offering a sleeker design.