Introduction and Conversion of Cooling Capacity Units

• Various Cooling Capacity Units:

There is an important indicator on the air conditioner, which is the cooling capacity. The core unit of cooling capacity in the International System of Units is Watt (W), but in different scenarios, there are different units are commonly used, such as Refrigeration Tons (RT), British Thermal Units (BTU/h), Horsepower (HP) and Kilowatts (kW), kcal/h, etc. Among them, the international standard unit is Watt (W), while Refrigeration Tons (RT), BTU/h and Horsepower (HP) are most widely used in air conditioning and refrigeration engineering.

• Conversion Between Different Units:

  • 1RT ≈ 3.517kW ≈ 12000BTU ≈ 3024kcal/h

  • 1kW ≈ 3412BTU ≈ 0.284RT ≈ 859.8 kcal/h

  • 1HP ≈ 2.5kW (air-cooled unit) ≈ 3kW (water-cooled unit) ≈ 8530~10236BTU

  • 1kcal/h ≈ 1.163W ≈ 3.968BTU

• An Example:

Small and medium-sized air conditioners often use HP to express cooling capacity, while large units often use RT. Scenario:

You're designing an air conditioning system for an office building that needs a cooling load of 100,000 BTU/hr.