What are psychrometric properties and how are they used in HVAC design?

Psychrometric properties describe moist air conditions including dry-bulb temperature, wet-bulb temperature, relative humidity, specific humidity, dew point, and enthalpy. The psychrometric chart graphically represents these properties and their relationships. In HVAC design, these properties are essential for calculating cooling/heating loads, designing air conditioning processes (cooling, heating, humidification, dehumidification), and ensuring thermal comfort. Understanding sensible and latent heat components is crucial for equipment sizing.