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Manual J

Manual J is the ACCA standard for calculating a home's heating and cooling loads, the starting point for sizing a heat pump.

Editorial staffEdited by heatpumpwiki

History 1

Manual J is the Air Conditioning Contractors of America's standard for residential load calculations. ACCA calls the current edition, ANSI/ACCA 2 Manual J (8th Edition), "the national ANSI-recognized standard for producing HVAC equipment sizing loads" for homes, and says it is "required by national building codes and most state and local jurisdictions."Source 1

It calculates heat loss and heat gain room by room from the actual house and local design temperatures. Equipment is then chosen with Manual S. See Manual J, Manual S and Manual D explained.

Sources

  1. 1.Manual J. Air Conditioning Contractors of America (ACCA). Accessed Oct 25, 2026

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