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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
Sarah Chen
Financial Analyst, CFA
Sarah is a Chartered Financial Analyst with over 8 years of experience in investment management and financial modeling. She specializes in retirement planning and compound interest calculations.
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