What this reference converts
Btu is an energy quantity. BTU/h, watts, and kilowatts are rates. Refrigeration tons are a cooling-capacity convention. This page compares units; it does not estimate a building’s heating or cooling load, electrical consumption, or equipment performance.
1 Btu1.055056 kJ (International Table Btu)
1 BTU/h0.29307107 W
1 kW3,412.141633 BTU/h
1 RT12,000 BTU/h
Formulas
W = BTU/h × 0.29307107
BTU/h = kW × 3,412.141633
RT = BTU/h ÷ 12,000
BTU/h = kW × 3,412.141633
RT = BTU/h ÷ 12,000
Capacity lookup table
| BTU/h | kW thermal | Refrigeration tons |
|---|---|---|
| 6,000 | 1.759 | 0.5 |
| 12,000 | 3.517 | 1 |
| 18,000 | 5.275 | 1.5 |
| 24,000 | 7.034 | 2 |
| 36,000 | 10.551 | 3 |
| 60,000 | 17.584 | 5 |
How to use the table
- Identify whether the starting value is an energy amount or a capacity rate.
- Use a row or formula to convert the capacity unit.
- Check manufacturer capacity at documented rating conditions for equipment selection.
- Calculate the load first for building sizing; conversion does not validate the result.
Example
A 30,000 BTU/h thermal capacity is 2.5 RT and approximately 8.79 thermal kW. It does not mean the unit consumes 8.79 kW of electricity.
Related tool
Convert a specific capacity value and copy the result.
BTU CalculatorSources
- NIST: British Thermal Unit (Btu) for the unit definition.
- U.S. Department of Energy: Central Air Conditioning for the load-calculation and equipment-selection context.