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How to Calculate BTU for Air Conditioning
Formula
BTU (British Thermal Unit) is the standard measure for AC cooling capacity. The required BTU depends on room size, ceiling height, insulation quality, and local climate.
A general rule is 20 BTU per square foot for well-insulated rooms and up to 35 BTU per square foot for poorly insulated rooms in hot climates.
Common use cases:
- Sizing a window or portable AC unit
- Central air conditioning capacity planning
- Comparing AC unit specifications
Frequently Asked Questions
Dr. David Park
Applied Mathematician, PhD Mathematics
David holds a PhD in Applied Mathematics from MIT. He has published research on numerical methods and computational algorithms used in engineering and scientific calculators.
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