Free HVAC Calculators
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Sizing
BTU Calculator
Calculate the BTU heating and cooling capacity needed for any room based on dimensions, insulation, windows, and climate zone.
AC Unit Size Calculator
Find the right air conditioner size for your home. Get tonnage, SEER rating recommendations, and estimated annual energy costs.
Heating Load Calculator
Calculate your home's heating load to properly size your furnace or heat pump. Based on insulation, window area, and outdoor temperatures.
Duct Size Calculator
Size your HVAC ductwork correctly. Calculate round duct diameter, rectangular equivalents, and static pressure based on CFM and duct specs.
Cost & Efficiency
Energy Cost Calculator
Calculate how much your HVAC system costs to run daily, monthly, and yearly. Compare SEER ratings to find potential savings.
Heat Pump vs Furnace Comparison
Compare heat pump vs furnace costs over 10 years. See annual costs, break-even analysis, and environmental impact side by side.
HVAC Cost Estimator
Estimate total HVAC installation costs including equipment, labor, and materials. Compare system types and get budget ranges.
Air Quality
Air Filter Size Finder
Find the right air filter size and MERV rating for your HVAC system. Includes replacement schedules and MERV rating explanations.
Refrigerant Charge Calculator
Estimate additional refrigerant needed for your AC system based on line set length. For licensed HVAC technicians.
Ventilation (CFM) Calculator
Calculate required airflow (CFM) for any room. Get exhaust fan recommendations and fresh air requirements per ASHRAE standards.
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