Work out enthalpy of air instantly with clear inputs, formula shown and shareable results.
Enthalpy of moist air is measured per pound of dry air and splits cleanly in two: the sensible term 0.24 x T for the air itself, and the latent term W x (1061 + 0.444 T) for the water vapour it carries. Coil loads are calculated on enthalpy difference because it captures both temperature and moisture change at once.
Moist air enthalpy
h = 0.24 T + W (1061 + 0.444 T)
h = 0.24 T + W (1061 + 0.444 T). Enthalpy of moist air is measured per pound of dry air and splits cleanly in two: the sensible term 0.24 x T for the air itself, and the latent term W x (1061 + 0.444 T) for the water vapour it carries.
A cooling coil removes both heat and moisture. Total capacity is 4.5 x CFM x Δh, which counts the latent work that a temperature-only calculation misses entirely.
This calculator takes 2 inputs: Dry bulb temperature, Humidity ratio. The pre-filled defaults are a realistic worked example — replace them with your own site or project figures.