The capacity of the air conditioner required depends on the volume of the room to be cooled and its heat load.
Cooling capacity is measured in kilocalories kCal/hr or British Thermal Units (BTU/hr).
An air conditioner that is too small for the room does not cool adequately, and one that is too large will cool the room before dehumidifying it, leading to a sweaty feeling.
Hence, consider these parameters before choosing the capacity of the air conditioner.