HVAC guides
Context for better tool use
Use a guide to understand the assumptions, formulas, and limits behind a calculation before acting on its result.
Load and capacity
Start with the load basis
Capacity conversion follows a documented load; it does not replace one.
How to Calculate HVAC Load
Understand the inputs behind a credible preliminary load.
LOADCooling Load Explained
Review solar, internal, and outdoor-air gains.
BTUWhat Is BTU?
Separate energy, BTU/h capacity, tons, and thermal kW.
BTUHow to Calculate BTU
Use a transparent component-load workflow.
LOADHeating Load Explained
Review the conditions and heat-loss inputs behind a heating calculation.
LOADHVAC Load per Square Foot
Understand what an area ratio misses before using a planning estimate.
LOADHVAC Load Calculation Mistakes
Catch omitted inputs and unsupported sizing shortcuts.
LOADWhy Oversized HVAC Systems Cause Problems
See why a larger nominal capacity is not automatically a better result.
Airflow and duct design
Follow the air path
Identify airflow purpose first, then check geometry and resistance.
What Is CFM in HVAC?
Understand airflow labels and air-stream purpose.
AIRFLOWAir Changes per Hour Explained
Use ACH as a volume-flow ratio, not a mixing guarantee.
DUCTHow to Size HVAC Ductwork
Connect airflow, area, velocity, and pressure checks.
DUCTDuct Friction Loss Explained
Separate straight-run friction from total system resistance.
AIRFLOWHow to Calculate CFM
Calculate airflow from a documented room volume and ACH basis.
AIRFLOWHow Many CFM per Room?
Separate room airflow questions from universal design targets.
AIRFLOWCFM per Square Foot Guide
Understand the limits of normalizing airflow by floor area.
BTU capacity
Read capacity labels correctly
Use these guides to distinguish energy, thermal capacity, unit conversion, and a documented space load.
Duct performance
Check the full air path
Velocity and sizing decisions need an airflow basis and a complete pressure-path review.
Refrigeration
Read measured refrigeration states
Keep thermal capacity, saturation data, and measured line-temperature differences in their correct context.
Psychrometrics
Understand the moist-air state
Read temperature, moisture, pressure, and energy as connected properties before using a load or airflow result.