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    AC Cooling Load Calculator (BTU) — Free Manual J Lite

    How many BTU do I need to cool a 1,000 sq ft house?

    A rough rule is 20–25 BTU/hr per square foot, so a 1,000 sq ft home lands around 20,000–24,000 BTU/hr, or about 1.5–2 tons. Hot climates, lots of west-facing glass, or poor insulation push it higher. This is a starting estimate only — an oversized AC short-cycles and will not dehumidify, so confirm with a Manual J load calculation.

    Run the numbers for your project

    Use the AC Cooling Load Calculator (BTU) — Free Manual J Lite to get an exact answer for your inputs.

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    Estimates and general guidance only. Verify against your local code and AHJ before any installation. Gas, electrical, and refrigerant work is hazardous to untrained users.

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