HVAC and building services
Rectangular duct equivalent diameter
Calculates a helper equivalent diameter for a rectangular duct from its side lengths, without HVAC equipment selection.
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Duct air velocity
Calculates duct air velocity from volumetric flow rate and cross-sectional area.
Simple absolute humidity
Calculates auxiliary absolute humidity from water vapor pressure and temperature without climate tables.
ACH from air flow
Calculates air changes per hour from air flow and room volume.
Heat-loss energy through partition
Calculates heat-loss energy through a partition from U-value, area, temperature difference, and time.
Condensate rate from humidity-ratio difference
Calculates condensate mass flow from dry-air mass flow and humidity-ratio decrease.
Condensation temperature margin
Calculates the difference between surface temperature and dew-point temperature without automatic building-compliance assessment.