Laboratory Sources & Standards
HVACLogic mathematical equations, physical derating coefficients, and editable presets are developed referencing published technical literature, national laboratories, and engineering standards.
Primary Engineering References & Standards
ASHRAE Handbook â Fundamentals (Chapters 18, 21, 30)
American Society of Heating, Refrigerating and Air-Conditioning Engineers
Governs outdoor climatic design conditions, duct design fluid mechanics (Darcy-Weisbach / Colebrook equations), and psychrometric state points.
Air Duct Friction Losses for Flexible Ductwork (Research Project 1333)
ASHRAE & Energy Systems Laboratory (Texas A&M)
Landmark research by Dr. Charles H. Culp, P.E., Ph.D. et al. establishing empirical fluid friction and boundary-layer turbulence penalties across 4% to 30% flexible duct compression and sag.
Manual J (8th Edition) â Residential Load Calculation
Air Conditioning Contractors of America
National ANSI standard for sizing residential heating and cooling equipment based on building envelope heat loss and sensible/latent heat gain.
Manual S (2nd Edition) â Residential Equipment Selection
Air Conditioning Contractors of America
Standard protocol for matching sensible and latent cooling capacities of OEM equipment to Manual J loads within 90%â115% tolerances.
Manual D (3rd Edition) â Residential Duct Systems
Air Conditioning Contractors of America
Comprehensive ductwork sizing methodology utilizing Total Effective Length (TEL), available static pressure, and equal friction rate calculations.
HVAC Duct Construction Standards â Metal and Flexible (4th Edition)
Sheet Metal and Air Conditioning Contractors' National Association
Standardizes duct gauge thicknesses, reinforcement requirements, fitting loss coefficients, and flexible duct sag derating curves.
Clean Air Act Section 608 & American Innovation and Manufacturing Act
United States Environmental Protection Agency
Mandates refrigerant recovery standards, leak rate repair thresholds, and phasedown protocols transitioning from R-410A to A2L alternatives.
Performance Rating of Unitary Air-Conditioning & Air-Source Heat Pump Equipment
Air-Conditioning, Heating, and Refrigeration Institute
Defines the test procedures for SEER2, EER2, and HSPF2 energy efficiency ratings under standard M1 static pressure testing.
International Energy Conservation Code â Residential & Commercial
International Code Council
Specifies prescriptive and performance-based building envelope insulation levels (R-values, continuous exterior insulation, and assembly U-factors).
Reference Fluid Thermodynamic and Transport Properties Database
National Institute of Standards and Technology
Provides high-accuracy pressure-temperature-enthalpy polynomial fits for single-component refrigerants and non-azeotropic zeotropic mixtures.
Explore Standards-Backed Calculation Hubs & Research
Airflow & Ducts â
Ductulator, flex duct CFM, and ACCA Manual D friction solvers.
Cooling & Loads â
ACCA Manual J cooling loads, AC tonnage, and mini-split sizing.
Field Diagnostics â
Superheat/subcooling, A2L PT chart, and psychrometric state points.
Heating Systems â
Heat pump balance points, furnace AFUE, boilers, and NFPA 54.
Building Science â
Building heat loss, infiltration leakage, and R-value assembly U-factors.
Research & Monograph Hub â
Open-access engineering monographs, lab manuals, and datasets.
ASHRAE Climatic Design Conditions âStandards Matrix âView Engineering Methodology âAbout HVACLogic âPrivacy Policy â