Capacity units
Cooling or heating capacity: BTU/h to kW and tons of refrigeration
- where
- capacity (kW)
- capacity (BTU/h)
- capacity (tons of refrigeration)
Explain this equation
Converts a capacity in BTU per hour into kW and tons of refrigeration. Use it when equipment data or a US specification quotes BTU/h.
B is the capacity in BTU/h. Multiplying by 0.29307107 gives watts and dividing by 1000 gives kW. Dividing B by 12 000 gives tons of refrigeration, because one ton is defined as 12 000 BTU/h.
Both are fixed unit conversions based on the international table BTU.
Sense check: 9000 BTU/h is about 2.6 kW, 12 000 is about 3.5 kW, 24 000 about 7 kW. Doubling B doubles every result.
Watch out: a unit marketed as “12 000 BTU” means BTU per hour at the rating conditions.
Converts a capacity in BTU/h to kW and tons of refrigeration.
Enter your values to see the result.
Good to know
Common split sizes: 9 000 BTU/h ≈ 2.6 kW, 12 000 ≈ 3.5 kW, 18 000 ≈ 5.3 kW, 24 000 ≈ 7.0 kW.
Common mistake
Treating “BTU” on a label as BTU per hour without checking; it nearly always means BTU/h.
Limits
Pure unit conversion using the international table BTU.
Sources
Results are calculations from the published methods and figures shown, and depend on the data you enter. Follow the equipment manufacturer’s data, CIBSE guidance, BS EN 378, the F-gas Regulations and your company procedures. Refrigerant work needs the correct F-gas certification.