Portable AC units are really effective at cooling the air in a room, in most instances for less than the price of a fancy fan. All you have to do is work out the size of the room you want to cool and select an AC unit with a suitable output, measured in British Thermal Units (or BTUs). A BTU is a unit for estimating thermal heat and it’s an important little acronym when it comes to selecting the right air conditioner for your abode. For instance, an air-con with 10,000 BTUs is good for a room of around 450 sq ft while a 5,000BTU model is suitable for a room of about 150 sq ft. Hence, it’s pretty important to know your room’s measurements or the unit could underperform.
However, there is a caveat with portable units and it’s the heated air that’s pumped out of the rear exhaust port. As the ‘law of conservation of energy’ states, energy (in this case heat) ‘can only be transformed or transferred from one form to another’. Hence, you will need to port the heated air generated by the AC out of the home using the supplied concertina hose that comes with every model. This can be done by either cutting a hole in the wall or a window (the most effective and most costly method) or by using the window kit that most manufacturers provide. As a last resort, simply dangle the hose out of an open window or doorway and sit closer to the unit.
Alternatively, if you’re lucky enough to have a working open flue fireplace (unlikely in the US), you could place the air con unit in front of it and all the heat will go straight up the chimney; after all, it’s what the chimney was designed for. This is by far the most hassle-free and tidiest way to enjoy the benefits of portable air conditioning but, for heaven's sake, make sure you’ve removed as much soot as possible from the fireplace first or it’ll be blown all over your furnishings.
Portable AC units are much louder than their built-in counterparts and that’s hardly surprising given that the compressors, pumps and fans are all in the same unit. By contrast, integrated systems have all the noisy stuff tucked away out of earshot so you rarely hear anything more than a gently whoosh. If you want a good night’s sleep with a portable air con in the room then you’re advised to turn it on a couple of hours before bedtime and keep the door closed. Then turn if off when hitting the sack – unless, of course, you’re lucky enough to be able to sleep through a hurricane.
Energy use and environmental impact are also worth considering. While modern AC units no longer use ozone-damaging chlorofluorocarbons (CFCs), they do sap a lot more power from the grid than a humble fan and that means slightly higher leccy bills and hence more pressure on the environment.
Now you’re no longer an air con newbie, have a scour through our carefully curated list of contenders and take your pick of the chillers.