What is BTU?
A British thermal unit (Btu) is a standard unit of energy that is used in the United States and sometimes in the U.K. It represents the amount of thermal energy necessary to raise the temperature of one pound of pure liquid water by one degree Fahrenheit at the temperature at which water has its greatest density (39 degrees Fahrenheit). The Btu is a measure in the so-called English system of units (the foot-pound-second system). Other countries use the joule, the unit of energy in the International System of Units (SI). A Btu is equivalent to approximately 1055 joules (or 1055 watt-seconds).
BTU is the abbreviation for British Thermal Unit, British standard unit of energy. BTU as a heating measure is used to determine heat requirements of bathrooms, kitchens and other parts of houses. Technically, one BTU is equal to the amount of heat required to raise the temperature of one pound of liquid water by 1 degree Fahrenheit at its maximum density, which occurs at a temperature of 39.1 degrees Fahrenheit. One BTU is equal to approximately 251.9 calories or 1055 joules.
