BUILDING ENGINEERING CALCULATORS
Free HVAC, ductwork and hydronic sizing tools
Soft Études provides practical preliminary sizing calculators. 38 technically reviewed HVAC, ventilation, thermal and hydronic tools are now available in English.
Hydraulic separator and heating manifold
Preliminary sizing of a hydraulic separator, heating manifold, primary and secondary flow rates, pipe connections and main dimensions.
Open calculatorExpansion vessel for heating and chilled water
Estimate the minimum expansion vessel capacity, expansion volume, operating pressures and a standard vessel size.
Open calculatorHeating water flow rate and pipe diameter
Calculate heating water flow rate, theoretical diameter, suggested pipe size and actual velocity.
Open calculatorCircular and rectangular duct sizing
Calculate a circular duct diameter, an equivalent rectangular size and an indicative insulation surface.
Open calculatorAirflow in circular and rectangular ducts
Calculate airflow from duct dimensions and air velocity, and compare circular and rectangular sections.
Open calculatorAir duct pressure loss
Calculate pressure losses by duct section, including linear, fixed and fitting losses.
Open calculatorCirculator selection and operating point
Calculate system flow rate and head, assess a control valve and check the operating point against a manufacturer pump curve.
Open calculatorPlate heat exchanger for heating and cooling
Preliminary plate heat-exchanger sizing with primary and secondary flow rates, LMTD, approach temperature, indicative area and connections.
Open calculatorDirect boiler heating circuit
Preliminary sizing of a boiler supplying one direct heating circuit without a hydraulic separator or manifold.
Open calculatorBoiler cascade preliminary sizing
Check installed output, N+1 redundancy, modulation range, primary flow and a generic component list for a boiler cascade.
Open calculatorHydraulic separation for heat pumps and hybrid systems
Compare primary and secondary flow rates, manufacturer minimum flow, buffer volume and indicative separator arrangements.
Open calculatorWater flow rate and AHU coil duty
Calculate water flow from heating or cooling duty, or sensible air-coil duty from airflow and supply-air temperature difference.
Open calculatorLocal pressure loss using K coefficient
Calculate local pressure loss through a bend, tee, valve or fitting from its K coefficient, flow rate and internal diameter.
Open calculatorHeat loss from circular pipes
Calculate linear heat loss, surface temperature, dew point, condensation or burn risk and indicative annual energy loss.
Open calculatorAHU airflow preliminary sizing
Estimate AHU airflow from air-change rate, occupancy, outdoor-air requirement or sensible cooling duty.
Open calculatorAirside free-cooling potential
Estimate sensible cooling available from outdoor air and compare it with the room sensible load.
Open calculatorMoist-air psychrometrics
Calculate dew point, humidity ratio, absolute humidity, enthalpy, air density and condensation or frost risk.
Open calculatorHeating and cooling load estimate
Simplified heating and cooling load estimate using overall heat-loss coefficient, exposed area and ventilation.
Open calculatorCold-room cooling load
Preliminary cold-room duty from envelope, air change, doors, lighting, people, products and evaporator fans.
Open calculatorRefrigeration COP
Compare actual refrigeration COP with an ideal Carnot reference and estimate annual electricity use.
Open calculatorU-values and insulation
Calculate multilayer wall U-value, compare insulation options and estimate associated transmission heat loss.
Open calculatorHeat-pump and chiller buffer-water volume
Estimate useful system water volume and any additional buffer-vessel capacity needed to limit short cycling.
Open calculatorAdditional refrigerant charge
Estimate additional liquid-line refrigerant charge from fluid, internal diameter, added length and liquid temperature.
Open calculatorRefrigerant pressure-temperature converter
Convert refrigerant saturation temperature, absolute pressure and gauge pressure, including bubble and dew values for blends.
Open calculatorHVAC refrigeration diagnostics
Diagnostic aid using suction and discharge pressures, line temperatures, superheat, subcooling and heat-exchanger approaches.
Open calculatorVRF refrigerant concentration check
Indicative VRF refrigerant concentration and safety check using charge, room area, low-point height, ventilation and refrigerant class.
Open calculatorCold-water flow rate and pipe diameter
Check cold-water flow rate, velocity, pipe diameter, pressure loss and residual pressure.
Open calculatorCollective and commercial cold/hot water supply
Estimate diversified cold- and hot-water flow rates, pipe size, velocity, pressure loss and residual pressure.
Open calculatorCollective and commercial DHW production
Compare instantaneous, semi-instantaneous and storage DHW production using demand, duty and storage volume.
Open calculatorDHW circulation pump selection
Estimate DHW circulation heat loss, minimum return flow, pipe size, pressure loss and pump head.
Open calculatorRainwater storage tank volume
Estimate useful rainwater storage from roof area, rainfall, collection efficiency, daily demand and autonomy.
Open calculatorIndividual solar DHW preliminary sizing
Estimate DHW demand, collector area, storage volume, solar fraction, backup heat and indicative savings.
Open calculatorCollective solar DHW preliminary sizing
Estimate collective DHW demand, circulation losses, solar collector area, storage, backup heat and savings.
Open calculatorSolar thermal expansion vessel
Estimate solar-loop fluid volume, vapour reserve, pressures and minimum expansion-vessel capacity.
Open calculatorFuel lower and higher heating values
Convert fuel quantity to energy using indicative LHV and HHV values for common heating fuels.
Open calculatorQuick heating-energy estimate
Convert fuel or electricity use to useful heating energy and estimate an indicative heat-pump equivalent.
Open calculatorHeat-pump selection assistant
Compare air-to-air, air-to-water, water-source and ground-source heat pumps from project constraints.
Open calculatorInternational heating-energy comparison
Compare heating and DHW scenarios using user-entered climate, energy prices, efficiencies and carbon factors.
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