HVAC Calculators & Tools
Professional calculators for HVAC technicians
Tonnage Converter
Convert between BTU/h, kW, refrigeration tons (RT), and kcal/h. Essential for comparing equipment specifications.
Refrigerant Charge Calculator
Calculate additional refrigerant charge based on liquid line length, pipe diameter, and system tonnage.
Electrical Load Calculator
Determine running amps (RLA), locked rotor amps (LRA), breaker size, and wire gauge for compressors.
Pipe Size Selector
Get recommended liquid and suction line diameters based on system capacity and refrigerant type.
Subcooling & Superheat Calculator
Calculate subcooling and superheat from pressure and temperature readings. Includes diagnostic feedback.
Heat Load Calculator
Estimate cooling load and AC tonnage for residential and commercial spaces. Simplified Manual J methodology.
Duct Sizing Calculator
Calculate duct dimensions based on airflow (CFM), velocity, and shape. Round and rectangular duct support.
Vacuum Pump Calculator
Estimate evacuation time based on pump CFM, system volume, and target micron level. Includes best practices.
System Diagnostic Tool
Input pressure and temperature readings to get instant diagnosis. Identifies charge issues, restrictions, and airflow problems.
Micron to Dew Point Converter
Convert vacuum micron readings to dew point temperature and moisture content. Essential for proper system evacuation.
Voltage Drop Calculator
Calculate wire size for long electrical runs. Ensure proper voltage at equipment with NEC-compliant sizing.
Refrigerant Identifier
Identify unknown refrigerants and detect contamination using pressure-temperature analysis. Compares readings against P-T curves.
Pressure Drop Calculator
Calculate pressure and saturation temperature drop in refrigerant piping. Includes fitting equivalent lengths and design guidelines.
Annual Energy Calculator
Estimate yearly HVAC operating costs based on system capacity, efficiency rating, usage patterns, and local electricity rates.
Equipment Comparison Tool
Compare HVAC equipment side by side. Analyze capacity, efficiency, operating costs, and total cost of ownership.
Water-Side & Central Plant
Chiller Selection Calculator
Calculate chiller capacity, chilled water flow rate, and sizing parameters for air-cooled and water-cooled chillers.
Pump Head Calculator
Calculate pump head, friction loss, and selection parameters for chilled water and condenser water systems.
Psychrometric Chart
Interactive psychrometric chart with air property calculations. Dry bulb, wet bulb, dew point, enthalpy, and humidity ratio.
Air-Side Systems
ERV/HRV Calculator
Calculate energy recovery ventilator sizing, sensible and latent heat recovery, and ventilation requirements.
AHU/FCU Selection Calculator
Calculate Air Handling Unit and Fan Coil Unit sizing. Includes coil selection, airflow, and static pressure.
VRF Piping Design Calculator
Calculate VRF/VRV refrigerant piping sizes, equivalent lengths, branch selector sizing, and oil return requirements.
Field Tools
Professional Engineering Tools
Advanced analysis tools for system engineers, energy auditors, and design professionals.
Operating Envelope Checker
Verify compressor operating conditions against manufacturer envelope limits. Check pressure ratio, discharge temperature, and oil return.
IPLV/NPLV Calculator
Calculate Integrated Part Load Value and Non-Standard Part Load Value for chillers per AHRI 550/590. Compare against ASHRAE 90.1 minimums.
Carbon Footprint Calculator
Calculate TEWI (Total Equivalent Warming Impact) including direct refrigerant emissions and indirect energy emissions. Compare refrigerant options.
Electrical Load Summary
Build HVAC electrical load schedules with demand/diversity factors. Auto-size transformers, main breakers, and cable runs. Export to CSV.
Annual Energy Simulation
Estimate annual HVAC energy consumption using bin method. Calculate cooling/heating loads by temperature distribution and part-load efficiency.
Pressure Drop Calculator
Calculate pressure and temperature drop in refrigerant piping. Includes fitting equivalent lengths and velocity checks.