Whether replacing an older, less efficient unit, or buying a new unit for a previously unair conditioned room, you should be impressed with the performance of newer models. The major attributes to consider include Cooling Capacity The ability of a unit to cool an area is measured in BTUhour. The higher the BTU, the more cooling power the unit has. However, don’t chose a model with too much cooling capacity, it will cycle on and off too often, wearing on the machine and not staying on long enough to remove humidity from the air. Make sure you have a rough estimate of the sizes of the rooms you want to cool in square feet before you start shopping.Energy Efficiency Look for high efficiency units. Efficiency is measured by the EER energy efficiency rating. All new units sold in the US must clearly display the EER. The higher the EER the more efficient the model and the lower your energy bill. A model with an EER of 10 should use about 20 less energy than one with an EER of Installation Requirements – Make sure that the unit is the right size for the window you plan to mount it in. Also, make sure you have enough help in installing the unit most are awkward and very heavy. Some require installation of a metal shell, while other require special electrical wiring

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