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BTU / kW Converter

Convert between BTU per hour, kilowatts and boiler horsepower — the three ways heating capacity gets quoted.

Value Unit

The conversions

1 kW ≈ 3,412 Btu/h
1 Boiler HP = 33,475 Btu/h

Why it matters for G3

A G3 certificate permits work on appliances up to 400,000 BTU/h under supervision, so being able to read a rating plate in whichever unit it uses is practical rather than academic. Electric heater questions on the exam typically give kilowatts and ask for BTU output — a 10 kW heater is about 34,100 Btu/h.

Studying for the G3 exam?

This is one of the figures the Ontario G3 exam expects you to know without reaching for a calculator. The app has 1,184 practice questions across all 9 syllabus topics, with a free 20-question mock exam.

Try the free mock exam →

What a G3 certificate permits →

Electricity and controls →

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