On the other hand, if the area you are going to be cooling has lots of shade and very little sunlight exposure, you may want to consider subtracting 10% of the recommended BTU. This is not always recommended, as it is better to have too many BTU’s than not enough. After adding 10%, you will have a better estimate of the cooling power you will need for this space. This is due to the added ambient heat added due to the environment. This may mean going up to the next available cooling power. Split-unit air conditioners tend to be more energy efficient, but these are more expensive and have to be permanently installed by a professional. We don't test split-unit air conditioners as they're less popular in the UK. Find out which retailers are rated highly by Which? members with our guide on the best and worst shops. Can you hire or rent an air conditioner?

According to the Centers for Disease Control and Prevention, air conditioners often operate around 60 dB, which is “comfortable” to listen to over a sustained period. That said, the Environmental Protection Agency recommends limiting exposure to indoor noises above 45 dB. Of course, these statistics don’t factor in your personal tolerance for ambient noise. Ultimately, the best advice we can give is that you should look for an AC that runs quietly, especially if you’re buying an AC that you want to last, and avoid any unit that hits above 60 dB. Are there smart features? Window and portable AC units offer roughly the same amount of cooling power for around the same price. However, they operate in different ways, which may determine whether one works better for you. Before making your choice, you should know what type of air conditioner you need to shop for. Air conditioners come in many sizes, often based on their cooling capacity. To figure out what size air conditioner you need, look at the size of the room or home you’re trying to cool. Measure the space to determine how many square feet you need your AC to cover. Energy Star’s buying guide features a geometry refresher to help people calculate a room’s area specifically for this purpose. Why it made the cut: The Frigidaire FFRE053WAE offers quiet operation, a programmable timer, and impressive energy efficiency at an affordable price.

Portable air conditioners FAQs

Remember that opening the windows on either side of your home will allow air to flow through. If you have a conservatory, keep the door between it and your home closed, as a lot of heat might leak from the conservatory into other rooms. How we test air conditioners Around two million tonnes of electrical and electronic waste are generated every year, so it’s important to dispose of your portable air conditioner correctly and in a way that isn’t harmful to the environment. With some air conditioner/dehumidifiers, you'll need to connect a hose (which might not be supplied) to drain the water. With others, you'll need to set the machine up as you would in air conditioning mode, with the hose out of the open window.

The following is a rough estimation of the cooling capacity a cooling system would need to effectively cool a room/house based only on the square footage of the room/house, as provided by EnergyStar.gov. Area To Be Cooled (square feet)Increase capacity for a room with high sun exposure; +10% cooling output. That would reduce the 5000 BTU AC room size to 90-135 sq ft. To find the desired change in temperature to input into the calculator, find the difference between the unaltered outdoor temperature and the desired temperature. As a general rule of thumb, a temperature between 70 and 80°F is a comfortable temperature for most people.

Portable air conditioners also use refrigerant gas to help cool your room. This can come in the form HFCs (hydrofluorocarbons), a greenhouse gas that when emitted can contribute to global warming. If yours is working properly, it shouldn’t release any HFCs. However, if the unit leaks or is disposed of incorrectly, that’s when harmful greenhouse gases can be released. Why it made the cut: Friedrich’s CCV08A10A is a simple-looking high-performing surprisingly quiet window air conditioner. This reduces noise by running the compressor and fan more slowly. Often, the target temperature will increase automatically across the night so you don't wake up freezing cold. If left in landfill, they can release the refrigerant into the environment. Some models contain HFCs, which are potent greenhouse gases. We've tested portable air conditioners from a range of popular brands, including AEG, Argos own-brand Challenge, DeLonghi and ElectriQ.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?

The 150 square footage coverage actually comes from the Energy Star air conditioner room sizing guide which states the following: Portable air conditioners often don’t meet the same specs as window units, but the Whynter ARC-14S comes close. It offers a respectable 11.2 EER rating while pumping out an impressive 14,000 BTUs of cooling power. That makes it one of the best energy-efficient air conditioners on the market. Before you get a portable unit, there are some more sustainable options to cool your home that you can try beforehand, such as using an electric fan or closing curtains.

How much does a portable air conditioner cost to run?

For example, a home owner in Atlanta might want to determine their BTU usage during winter. Atlanta winters tend to hover around 45°F and temperatures may fall as low as 30°F occasionally. Given that the desired temperature of the residents is 75°F, the desired temperature increase would be 75°F - 30°F = 45°F. This is a general purpose calculator that helps estimate the BTUs required to heat or cool an area. The desired temperature change is the necessary increase/decrease from outdoor temperature to reach the desired indoor temperature. As an example, an unheated Boston home during winter could reach temperatures as low as -5°F. To reach a temperature of 75°F, it requires a desired temperature increase of 80°F. This calculator can only gauge rough estimates. Room/House Width Lastly, you want to consider whether or not your space is open or confined. Our square footage recommendations are meant for confined areas, so if your room open ups into another space without the option of closing a door, you will want to add in that other space. For example, if you want to cool a kitchen that opens into a living room, you will want to combine the size of those two rooms as if they were one space and use that as your determinate square footage.