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Btu (British thermal unit)

A Btu is the heat needed to raise one pound of water by one degree Fahrenheit, and heat pump capacity is given in Btu per hour.

Editorial staffEdited by heatpumpwiki

History 1

A Btu (British thermal unit) is a unit of heat. EIA defines it: "One Btu is the amount of heat needed to raise the temperature of one pound of water by 1° Fahrenheit (F)."Source 1

Heat pump and furnace capacity is given in Btu per hour (Btu/h). A 36,000 Btu/h heat pump is a 3-Ton unit.Source 2

Useful conversions from EIA:Source 1

Energy Btu
1 kilowatt-hour of electricity 3,412
1 therm of natural gas 100,000
1 gallon of propane 91,452

The kWh figure links Btu-based ratings to COP (coefficient of performance): an efficiency in Btu per watt-hour divided by 3.412 gives a COP. See HSPF2 and SEER2.

Sources

  1. 1.British thermal units (Btu). U.S. Energy Information Administration. Accessed Oct 25, 2026
  2. 2.Heating and cooling with a heat pump. Natural Resources Canada. Accessed Oct 25, 2026

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