About Units

Btu per hour: BTU per hour (BTU/h) is a unit of power that describes the power of heating and cooling systems, such as furnaces, ovens, and air conditioners. One BTU per hour is the rate at which one British Thermal Unit of energy is transferred in one hour. For example, the cooling capacity of a residential air conditioner might be rated at 10,000 BTU per hour.

Tons of refrigeration: A ton of refrigeration (RT) is a unit of power used to describe the heat-extraction capacity of air conditioning and refrigeration equipment. One ton of refrigeration is equal to the rate of heat transfer needed to freeze 1 ton (2000 pounds) of water at 0°C in 24 hours, equivalent to 12,000 BTU per hour or approximately 3.517 kilowatts.