HVAC BTU Calculator
A rough cooling load from the floor area — a range in kW, not a specification.
A rough cooling load from floor area — about 430 BTU per square metre. It is a range to get in the right band, not a specification. Have a technician size the real system.
Measure
Rough cooling load
5 kW
About 17,200 BTU/h (5.04 kW) for 40 m². A sensible band is 4.3–5.8 kW. Glass, insulation, and climate will move this.
- BTU/h
- 17,200
- Range
- 4.3–5.8 kW
- Uses ~430 BTU per m² (about 40 BTU/ft²).
- Not a certified heat load. Do not buy a unit from this number alone.
Rough load5 kW
Measurements stay in this browser. Nothing is uploaded.
Worked example
A 40 m² room at about 430 BTU per square metre needs about 17,200 BTU/h, which is about 5.0 kW. A sensible band is about 4.3–5.8 kW. That is a rough screen, not a heat load.
FAQ
- Where does 430 BTU per square metre come from?
- It is a rule of thumb from about 40 BTU per square foot. Real loads depend on glass, insulation, and climate.
- How do you convert BTU/h to kW?
- Divide by 3,412.
- Can I size a unit from this alone?
- No. Use it to get in the right range, then have the system sized properly.