Air conditioning units are quickly becoming the norm in today's world and can be found in homes, offices, and transportation systems all over the country. So why are these technological marvels so popular? Air conditioning units provide a controlled comfortable climate that can be altered according personal preference - whether it be too hot or too cold an air conditioner will make it just right.

Not only is the temperture manipulated but the air has the added benefit of being dehumidified and cleaned by means of series filtration systems . Some units also have special filters that are designed to remove pollutants contained within the air.

The principle is generally based on the same principles that are found in your modern refrigerator, but on a larger scale whereby the area that is being controlled is now extended to cover a whole room or building. Air conditioners have three primary parts - a compressor, a condenser and an evaporator.

The coolant or refrigerant is in a vapor form when it reaches the condenser - here it is then put under immense pressure, so much so that it is converted in to its liquid form and the excess heat energy removed. Looking at the condenser more closely you will notice it has fins similar to that found on a car radiator, these fins help disseminate the heat faster.

The liquid coolant then flows down the air conditioning unit through to the evaporator coils where it latterly absorbs the heat from the air that has been drawn in. This process causes the coolant to transform into a gas. The evaporator is also equipped with small metal fins which aids in the transferring the heat from the air to the coolant. When the working fluid leaves the condenser, its temperature is much cooler and it has changed from a gas to a liquid under high pressure. This is then channeled back up through to the condenser and the process is repeated till the desired temperature on the thermostat is reached.

The Department of Energy has put together a set of efficiency standards that dictate the minimum requirements for air conditioning units. The unit that is used to measure this is the "SEER", otherwise known as seasonal energy efficiency rating. Generally speaking the higher the SEER the more energy efficient the air conditioning unit will be - ideally you would want one rated 12 to 17.

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