Latent and sensible cooling and heating calculations

Latent Heat

To calculate the latent heat due to moisture in the air we can use this equation

hl = 4,840 q dwlb

hl is the latent heat in Btu per hour

q is the air volume flow in cubic feet per minute

dwlb is the humidity ratio difference in lb water per lb dry air

Sensible Heat

To calculate the sensible heat in a heating or cooling process of air we can use this  equation

hs = 1.08 q ΔT

hs is the sensible heat in Btu per hour

q is the air volume flow in cubic feet per minute

ΔT is the temperature difference in °F

Total Heat – Latent and Sensible Heat
To calculate the Total heat(Sensible and Latent Heat) due to both temperature and
moisture we can use this equation

ht = 4.5 q Δh

ht is the total heat in Btu per hour

q is the air volume flow in cubic feet per minute

Δh is the enthalpy difference in btu per lb dry air

Or we can calculate the Total Heat by using this equation

ht = hs + hl= 1.08 q dt + 0.68 q dwgr

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