HVAC & Plumbing Calculators
Practical preliminary engineering calculators for HVAC and plumbing design, including duct pressure drop, ERV/HRV calculations, water flow, heating, cooling, water heater sizing, and psychrometric processes.
Use these tools for preliminary reference only. Final design should be verified by a qualified mechanical professional and applicable local codes.
Duct Pressure Drop Calculator
Estimate duct velocity, friction loss, equivalent length, and total pressure drop for preliminary ductwork design.
ERV/HRV Calculator
Estimate supply air temperature and heat recovery performance using sensible, latent, and total effectiveness.
Chilled Water GPM Calculator
Calculate chilled water flow rate based on cooling capacity, temperature difference, density, and specific heat.
Heating Water GPM Calculator
Calculate heating water flow rate based on heating capacity, temperature difference, density, and specific heat.
Water Heater Sizing Calculator
Estimate domestic hot water demand, storage capacity, recovery rate, and preliminary electric water heater sizing.
Psychrometric Process Calculator
Evaluate sensible heating, sensible cooling, cooling and dehumidification, humidification, and air mixing processes.
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