How to check the capacity of the A/C system
You can check the capacity of the air conditioner basing on the model code.
(4), (5) shows the capacity of the air conditioner.
09 : 9,000 Btu / 12 : 12,000 Btu / 18 : 18,000 Btu / 24 : 24,000 Btu
What is BTU?
A BTU is the amount of heat required to raise the temperature of 1 pound (0.454 kg) of liquid water by 1 °F (0.56 °C) at a constant pressure of one atmosphere. As with calorie, several BTU definitions exist, which are based on different water temperatures and therefore vary by up to 0.5%. A BTU can be approximated as the heat produced by burning a single wooden match or as the amount of energy it takes to lift a one-pound weight 778 feet (237 m).