ACCA Manual J · ASHRAE 2021 · IECC 2021

HVAC Load Calculator

Calculate the correct heating and cooling capacity for your Maryland property using the industry-standard ACCA Manual J methodology. Answer 4 quick steps and get BTU requirements, recommended system size, and efficiency improvement opportunities.

✓ Based on ACCA Manual J 8th Ed.✓ Maryland Climate Data (NOAA)✓ IECC 2021 Envelope Standards✓ 100% Free · No Sign-up

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Location (Maryland)(Affects design temperatures per ACCA Manual J)

Disclaimer: This calculator provides a simplified ACCA Manual J estimate (±10% accuracy) for preliminary equipment sizing decisions. Calculations use ACCA Manual J 8th Edition methodology, ASHRAE 2021 Fundamentals psychrometric data, NOAA climate normals for Maryland, and IECC 2021 Climate Zone 4A (Mixed-Humid) envelope parameters. For permit submittals, MEP coordination, or commercial projects, a licensed HVAC engineer must perform a full Manual J with room-by-room analysis. Diaz Sheet Metal provides complimentary full Manual J calculations with every equipment quote.