Cooling
BTU / kW Conversion Reference
Conversion factors and a quick-lookup table between kW, watts, BTU/h, refrigeration tons and kcal/h — the five units cooling-capacity nameplates and datasheets typically mix between regions. Use alongside the BTU / kW Converter.
Last updated: June 2026
Terms
- CRACComputer Room Air Conditioner
- The specialized air-conditioning unit that cools a server room.
- IECInternational Electrotechnical Commission
- The international body that writes electrical safety standards used across most of the world outside North America. When a chart cites an IEC number, it's pointing to the official rulebook behind a calculation.
Conversion Factors
1 kW = 3 412.14 BTU/h = 0.2843 tons = 860.42 kcal/h
1 ton of refrigeration = 12 000 BTU/h = 3.517 kW
1 BTU/h = 0.293 W | 1 kcal/h = 1.163 W
Quick Lookup — Common Cooling Capacities
| kW | Watts | BTU/h | Tons (TR) | kcal/h |
|---|---|---|---|---|
| 1 kW | 1 000 | 3 412 | 0.28 | 860 |
| 3.5 kW | 3 500 | 11 943 | 1.00 | 3 011 |
| 5 kW | 5 000 | 17 061 | 1.42 | 4 302 |
| 7 kW | 7 000 | 23 885 | 1.99 | 6 023 |
| 10 kW | 10 000 | 34 121 | 2.84 | 8 604 |
| 17.6 kW | 17 600 | 60 053 | 5.00 | 15 145 |
| 35.2 kW | 35 200 | 120 107 | 10.00 | 30 291 |
| 100 kW | 100 000 | 341 214 | 28.43 | 86 042 |
Ton sizes (1, 5, 10 TR…) are common nameplate steps for packaged AC/CRAC units in North American markets; kW steps are more common in European/IEC datasheets.
Where Each Unit Shows Up
| Unit | Typically used in | Watch out for |
|---|---|---|
| kW | European/IEC datasheets, electrical load calculations | Cooling kW (thermal) vs electrical kW input (compressor power) are different numbers — check which one a spec sheet means |
| BTU/h | US/UK residential and small split-system AC nameplates | Often rounded to marketing numbers (9 000 / 12 000 / 18 000 BTU/h) |
| Tons (TR) | North American commercial/packaged HVAC, chillers | "Ton" here means a unit of cooling power, not a unit of mass — historically the heat to melt one short ton of ice in 24 h |
| kcal/h | Older European, Japanese and some Asian-market HVAC datasheets | Increasingly replaced by kW on modern equipment, but still common on legacy nameplates |
Frequently Asked Questions
Why do AC units list both BTU/h and kW?
Many international manufacturers sell into both BTU/h-native markets (US, parts of Asia) and kW-native markets (Europe). Listing both avoids needing region-specific datasheets, and lets installers cross-check a nameplate value against local design documents in whichever unit they normally use.
Is "1 ton of cooling" related to weight?
Only historically. A refrigeration ton originally meant the cooling power needed to freeze one short ton (2 000 lb) of water into ice in 24 hours — about 12 000 BTU/h. Today it's used purely as a cooling-capacity unit, with no weight measurement involved.
Is the cooling kW the same as the electrical kW the unit draws?
No — they're often very different. Cooling kW (thermal output) divided by electrical kW (compressor input) gives the unit's coefficient of performance (COP) or EER. A unit might output 10 kW of cooling while drawing only 3–4 kW of electricity (COP ≈ 2.5–3.3). Always check which figure a datasheet quotes before sizing electrical infrastructure.
How does this relate to the Cooling Load Calculator?
The Cooling Load Calculator tells you how much cooling capacity (in kW) a room needs. This converter then translates that requirement, or an existing unit's nameplate rating, into whatever unit your supplier or local market uses.