Air Conditioning: What Size Do I Need?

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Air conditioning units are available in a variety of sizes, but what size do you need for your home? We explain how to calculate the size and power of the unit to ensure you get the most from your investment.

Calculate the right size

Similar to how you would calculate the size of radiator in a room, you also need to use the British thermal unit (BTU) system to determine the size of the air conditioning unit. A BTU represents the amount of energy needed to heat one pound of water by one degree Fahrenheit.

In general terms, most living rooms will require an air conditioning unit that produces between 5,000 to 8,000 BTUs. The first thing to do is to measure the height, width and length of the room in question. To get a more accurate calculation for your room you can use the following formula to get the right BTU level.

> Find out more about how home air conditioning units work – click here

For example, if a room measures 16x11x9 feet: 16 x 11 x 9 x 5 = air conditioning unit that can produce a minimum of 7,920 BTUs.

If energy efficiency is a major concern look for air conditioning units that have a strong energy efficiency ratio (EER). This measures the ratio between the power input (in watts) and the BTU. The general rule is that the higher the EER rating the more efficient the system will be.

Air conditioning units also fall into certain energy classes. Manufacturers must self-certify whether their unit is in the A to G energy class, although sometimes they might not be always be as accurate as advertised. This is why speaking with a professional installation company can make all the difference, as a site survey will ensure the recommended unit is suited to the exact needs of the space.

What to look for when buying an air conditioning unit?

Other things to look out for when buying an air conditioning unit include:

Get a free survey and quote

If you want to improve the air quality in your home and have greater control over the temperature, get in touch with AAC today to arrange a free quote and survey at a time that suits you. Email or call 01707 32 55 66.

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