Everything we get in the world today has to meet a particular standard. They are all rated to meet some criterion that describes their quality. Air conditioning units are no different and are also rated. There are two major measurements that describe an air conditioner’s performance.

• BTU ( British Thermal Unit )
• EER ( Energy Efficient Ratio )

The BTU of an air conditioner is equivalent to the capacity of the unit. The BTU range that air conditioners are available in is from 5,000 units to 18,000 units. So if an air conditioner has a high BTU, the capacity of the unit will be high as well. Although, you have to keep in mind that an air conditioner will be more expensive if it has a higher BTU rating.

The EER rates the unit on its efficiency as it is working and consuming energy. An air conditioning unit will consume less power if the EER rating is high. This in turn will result in lower electricity bills.

Another important feature that should be taken into consideration is whether the unit emits pollutants. The rating of an air conditioner decreases if it discharges pollutants which are hazardous to the environment. It is advisable to buy a unit that has a ‘no CFC’ label as it does not let out harmful pollutants. The noise factor must also be considered. There are some units that while working make a humming sound, while others you cannot hear at all.