Chris Roth, CEO and owner of National Technical Institute for insights on selecting the best air conditioner for your home

All of the models we've tested are heavy (up to 30kg) and awkward to lift out of the box. If you live alone, we suggest you get someone to help you set it up, particularly if you're pregnant or elderly. We've tested portable air conditioners from a range of popular brands, including AEG, Argos own-brand Challenge, DeLonghi and ElectriQ. Overall, we were very satisfied with how well the De'Longhi Pinguino was able to cool a large space, and we found it to be unobtrusive and quiet. Installation can leave some small gaps; consider adding additional foam or sealing with gaffer’s tapeIf you want to lower the temperature in the room by more than a few degrees then you need an air conditioner; similarly, if your room is large, then an air cooler probably won’t work very well.

Depending on the power output of the portable air conditioner, these devices can cool spaces from about 100 to 800 square feet. Q. Can I use a portable air conditioner in a room with no windows? We also liked that the unit provided a clear and constant update of the room temperature and that you're able to set a timer and change the settings easily from the unit or with the remote control. The filters inside the units are designed to catch dust so if they are not cleaned regularly they can become clogged, collect moisture and may even become mouldy.

How do portable air conditioners work?

The Midea Duo 14,000 BTU portable air conditioner with heat is powerful enough to cool, warm, dehumidify, and circulate the air in rooms up to 550 square feet. It uses variable-speed inverter technology to increase energy savings by 40 percent in comparison to U.S. federal standards. Multiply the dimensions (in feet) of the room by five. So for a room measuring 15ft x 10ft x 8ft, you would calculate 15 x 10 x 8 x 5 = an air conditioner of 6,000 BTUs. Air conditioners don't have to be big or bulky though - there are many portable models out there that don't require any complicated installation. In our experience, Midea makes solid air conditioners that are good value, but they don't always feel as premium as their more expensive cousins. The digital control is really clear and easy to use, with three modes - air conditioning, fan and dehumidifier. You can select the fan speed and choose to have maximum or medium power or to make the unit silent.

During the testing of this unit, we really loved the sleek design, plus it was one of the easier units to wheel around from room to room despite its heavy weight of 72 pounds. The LED display was very intuitive and easy to use and read. When cooling an 80 degree Fahrenheit room, it brought the temperature down in our 600-square-foot living space in under an hour, making it one of the more powerful units on our list. The only downside is that the vent is on the top of this unit, which makes it hard to direct the airflow and is therefore not as easily adjustable as some other units. We find a lot of customers get these units for bedrooms,” says Appliance Direct’s Jake Crossley. “7,000 BTUs is the output we would recommend for rooms up to 18 square metres. Any larger and you won’t get the full benefit.”Many newer air conditioners are WiFi-enabled, so you can control them via your phone, a handy extra that means you can get your house cooling down before you've even stepped inside. How much does an air conditioner cost? The Honeywell Contempo Series of Portable Air Conditioners offers an efficient and altogether quieter means of cooling your surrounding area. Worried about the loud and often intrusive sound of a portable ac unit disrupting your day or worse yet, your night's sleep? Lay that worry to rest as Honeywell Contempo Air Conditioners operate within the 52-55 dbA range. What does that mean though? It means that your portable air conditioner will operate fully while remaining within the same noise range of an average conversation between two people in a quiet room. Learn More How about Honeywell HF Smart Wi-Fi Portable Air Conditioners? You could also look at the claimed energy class. Air conditioner manufacturers are obliged to self-certify their energy class, from A to G. However, we conduct our own expert tests according to the European Standard BS EN 14511:2013. Often, we find the claimed and actual energy class to be different. Can you buy an eco air conditioner? Neither the lightest nor heaviest option on this list, the Whynter ARC-14-S weighs 73 pounds—and it has four rolling wheels to make the job of moving it around much easier. If you store this unit away during the cooler months of the year, a protective cover safeguards the housing and keeps out dust and dirt. Air conditioners with a BTU rating of 10,000 or higher are typically the most efficient at cooling a room, but the higher the BTU, the louder and heavier the model. Most AC units also come with an Energy efficiency Ratio (EER). A higher EER rating equates to greater efficiency; EER indicates the ratio of the air conditioner’s BTUs per hour to its power input, measured in watts.