kW to BTU/hr Converter

Sizing electric heaters rated in kW for US building codes.

Comparing heat pump performance across metric and US datasheets.

In the global boiler market, European manufacturers (Viessmann, Bosch, Buderus, Baxi) rate output in kW (a 30 kW residential gas boiler is 102,000 BTU/hr) while their US counterparts (Burnham, Weil-McLain, U.S.

Boiler Company) rate in BTU/hr (a 100,000 BTU/hr residential boiler is 29.3 kW), and engineering teams specifying equipment for international projects or for facilities with mixed equipment populations must convert fluently.

AHRI (Air-Conditioning, Heating, and Refrigeration Institute) certified ratings for chillers in North America use BTU/hr (or 'MBH' for thousand BTU/hr) and tons of refrigeration as the primary units, while Eurovent certified ratings for the same European-manufactured chillers (Trane, Carrier, Daikin, Mitsubishi Electric) use kW for cooling capacity — a 500-ton (1,758 kW) chiller from Trane in the US is rated 6,000,000 BTU/hr but its EU spec sheet reads 1,758 kW, and the conversion is required for any project mixing US and EU documentation.

Heat pump COP and SCOP ratings in the EU (per EN 14511 and EN 14825) are dimensionless ratios of thermal output (in kW) to electrical input (in kW), while US SEER, EER, and HSPF ratings use BTU/hr per watt (EER) or BTU/hr per Wh per year (HSPF) — the conversion between the EU and US metrics is mechanical but is essential for comparing like-for-like equipment from different markets.

Data center cooling capacity planning is increasingly done in kW per rack (the ASHRAE TC 9.9 thermal guidelines for data centers specify rack densities from 5 kW to 40+ kW), while legacy data center documentation was in BTU/hr per rack (a 5 kW rack is 17,061 BTU/hr, a 40 kW rack is 136,486 BTU/hr), and facility teams working on both old and new data center builds must convert between these conventions constantly.

Electric resistance heating elements for industrial process heating, comfort heating, and duct heaters are universally rated in kW (since the input is electrical), but the thermal output in US project specifications is converted to BTU/hr to match the rest of the HVAC documentation.

Tankless water heaters, electric boilers, and electric furnaces in residential and light commercial use are rated in kW (a 27 kW electric tankless water heater delivers about 92,000 BTU/hr of hot water heating), and US installers must convert to BTU/hr for sizing against a US-spec gas water heater (typically 199,000 BTU/hr).

Refrigerated transport (reefer) containers, refrigerated trucks, and intermodal containers are rated in kW of cooling capacity in international shipping (a Carrier Transicold PrimeLINE reefer unit is typically 6–17 kW of cooling) but in BTU/hr or tons in US-domestic shipping — the conversion is required for international cold-chain logistics planning.