BTUh

BTUh, commonly written as BTU/h or BTUH, is a unit of power used in the HVAC industry to express the heating or cooling capacity of equipment. It represents the rate at which heat is transferred or removed. The term derives from the British thermal unit (BTU), which is the amount of heat required to raise the temperature of one pound of water by one degree Fahrenheit at standard pressure. One BTU per hour equals one BTU of heat transfer per hour. In SI terms, 1 BTU/h is approximately 0.293 watts.

Equivalents and context: 5,000 BTU/h is about 1.46 kW, and 12,000 BTU/h is about 3.52 kW. The “ton” of refrigeration, a common sizing reference in cooling, is defined as 12,000 BTU/h (roughly 3.5 kW). BTUh is used to rate the capacity of furnaces, air conditioners, heat pumps, and water heaters.

Regional use and standards: BTUh remains common in North America, where equipment capacities are often specified in BTU/h. In many markets, metric units (kilowatts) are also used, but BTU/h appears on product labels, performance charts, and codes that follow Imperial or customary units.

Summary: BTUh denotes the rate of heat transfer (power) measured in British thermal units per hour, and is a foundational unit for describing HVAC equipment capacity in the United States and parts of Canada. It ties to kilowatts via 1 BTU/h ≈ 0.293 W, with larger capacities typically expressed in multiples of 12,000 BTU/h (tons).