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Move these handy portable ACs between rooms to circulate a deliciously icy breeze
While you can try draping a damp towel over your body and sticking your tower fan on full blast in an attempt to stay cool, sometimes the summer heat can still be unbearable. However, the best portable air conditioners are here to help.
When the temperature rises, the most effective solution for overcoming heatwave blues is an air conditioner. Unlike fans, which simply circulate hot air, air conditioners extract the hot air from your room and replace it with a refreshing cool blast instead.
However, wall-mounted air conditioners are expensive, and, chances are, you’re mainly going to be using them for mini heatwaves, which come in spurts throughout the summer here in the UK. You’re not going to be using an AC enough throughout the year to make them worth the cost of installation, making portable air conditioners (PACs) a better investment.
Portable air conditioners can be carted from bedroom to office to living room, and they can be easily packed away and stored for the winter. All PACs are vented via a duct through a window or wall – the hot air needs to go somewhere to get it out of your home. While most of them come with window kits to make them as energy-efficient as possible, they’ll really only work with sliding or sash windows. You’ll most likely have your window wide open whenever you use a PAC, so bear that in mind.
It’s also worth noting that, while they’re technically portable, PACs are large machines, because of all the engineering inside. There’s an evaporator, a condenser and a compressor. They’re heavy, but they offer a sure-fire way to cool down a room. If you want something slightly better than a fan, there are always air coolers, which are smaller and lighter than PACs, but make the room quite humid.
It’s also worth noting air conditioners are measured in British Thermal Units (BTUs) – the higher the BTU, the more powerful the portable air conditioner. A portable air conditioning unit with 7,000 BTUs will cool a small room of around 18-20 square metres, but always check the size of the room before you buy. A unit with too low a BTU for the space won’t cool it effectively.
We reviewed a range of portable air conditioner units in our homes – in living rooms, bedrooms and offices, and even inside a caravan – over especially hot days, to find the best. We took into account the price, portability, cost and how well they cooled us down, despite baking temperatures outside.
One of our testers lives in a flat that consistently reaches temperatures of up to 30C when the outside temperature ranges from the low to mid-20s, acting as a perfect test environment for reviewing portable air conditioners.
The best portable air conditioners come with added features, such as a programmable timer, an in-built dehumidifier and smart app controls. Here’s our pick of the best, whether it’s for a stuffy office, balmy nights, or a conservatory, where intense heat can build up quickly.
What makes portable air conditioners so effective is that, unlike fans, which just cool you down, portable air conditioners physically lower the temperature in the room. It does this by sucking up the hot air inside the room, expelling that hot air out through the window, via an exhaust hose, and then replacing that hot air with cooler air. Fans, on the other hand, just circulate a breeze around the room, which is still effective, but not on extremely hot days.
Portable air conditioners can cost anywhere between £250 to more than £1,000, depending on the product’s BTU rating. While fans are considerably cheaper, portable conditioners are worth investing in if you’re looking to cool down a larger space.
Cheaper models with a lower BTU rating tend to be below the £300 mark and generally aren’t worth buying unless you want to condition a small room. Higher BTU models are bigger, pricier and can cool a larger space.
Portable air conditioners cost significantly more than fans to run. They cost roughly 44p per hour. If you use your air conditioner for 4 hours and 18 minutes during the day – the UK average – and 4 hours and 48 minutes at night, it’s estimated you’ll pay roughly £28 per week. Air conditioners with an A energy rating are the most efficient to run.
If you’re not investing in an air conditioner that can set timers or has a smart app, we’d recommend investing in a smart AC controller, such as the Tado smart AC control V3+, as this will help you manage and control your unit, so it runs more efficiently.
While portable air conditioners are loud machines, they’re not noisy enough to disrupt your sleep. Most range between 40dB and 60dB. To quantify that, a regular conversation is about 50dB, while a washing machine is about 70dB. The models in our round-up range between 44dB and 64dB.
On the whole, portable air conditioners are going to be loud, but not as loud as a washing machine spinning next to your bed. If you’re after a particularly quiet model, the EcoFlow wave 2 is the quietest portable air conditioner in our list, at just 44dB. Bigger or more BTUs doesn’t mean louder, either. Both MeacoCool models on our list range between 51dB and 53dB, despite the series 14000 having double the BTUs of the series 7000.
The most important thing to pay attention to when buying a portable air conditioner is the number of British Thermal Units (BTUs) of each model. A 5,000 BTU portable air conditioner is typically the smallest and will cool down a small room; a 7,000 BTU air conditioner is rated to cool down an 18 square-meter room. Medium-sized rooms and bedrooms roughly 24 square-meters in size will need something between 8,000 BTUs and 10,000 BTUs to run efficiently, and larger rooms will need something with 12,000 BTUs and above.
We’d also recommend looking for some specific features that make your portable AC more efficient and smarter to run. An in-built fan, dehumidification mode, a timer and smart controls are all useful features to have.
There are a few ways to vent a portable air conditioner without a window. These include placing the portable air conditioning unit near an external door or adding a vent to a wall or ceiling.
Portable air conditioners typically use anywhere between 700W to 1,500W, depending on the BTU rating. The amount of electricity used per hour then varies according to this wattage number.
To install a portable air conditioner, place it near a window or exit and ensure the window kit (if one is included) creates a secure seal. After this, position the ventilation pipe according to its length.
The type of air conditioner you buy depends on the size of the room you want to cool. Portable conditioners with a BTU of 9,000 or 12,000 can cool a room of around 21 or 30 square metres, respectively, while anything below will only cool smaller spaces. Experts recommend multiplying the dimensions of your room by five to find your necessary BTU.
You might also want to consider noise; if this is a concern, go for a model with sleep mode, which automatically switches off the air conditioner once the room has reached the right temperature.
Fully self-evaporative models automatically evaporate moisture out of the exhaust hose along with warm air, while older manual removal needs you to drain the collected moisture manually to enjoy a continued cooling effect.
While some conditioners are self-evaporating and don’t require manual removal of condensate water, standard portable conditioners have buckets that need to be emptied periodically – anywhere between eight hours or up to a month, depending on the model. Even some self-evaporating models need emptying after long-time use.
The MeacoCool MC pro series 9000 was definitely the easiest air con unit to use at home, thanks to its longer hose, smaller size and wifi support. Unless you’re cooling a huge area, it’s a no-brainer. For slightly bigger rooms, look to the De’Longhi pinguino or the slightly heavier and bulkier MeacoCool MC series 14000. The VonHaus 7,000 BTU model is a great choice if you’re on a tight budget, though, the hose is quite short and there aren’t too many extra features.
Want more warm-weather essentials? Check out the best fans