Relative Humidity (RH)
Relative humidity (RH) is a measure of the amount of water air can hold at a certain temperature. Air temperature (dry-bulb) is important because warmer air can hold more moisture…
Temperature: Wet Bulb
The wet bulb temperature (WBT) is a temperature associated with the moisture content of the air. Wet bulb temperature is taken by surrounding the thermometer with a wet wick and…
READING PSYCHROMETRIC CHART
To the novice, a psychrometric chart seems a dizzying maze of lines and curves going every which way, but once a few fundamental things are understood about the psych chart,…
Psychrometric Chart
The Psychrometric Chart provides a graphic relationship of the state or condition of the air at any particular time. It displays the properties of air: dry bulb temperature (vertical lines),…
PSYCHROMETRICS
Psychrometrics is the science of studying the thermodynamic properties of moist air. The amount of moisture vapour in the air varies quite significantly under different conditions. When the air is…
Determine Design Supply Airflow Rate
HVAC engineers use psychrometrics to translate the knowledge of heating or cooling loads (which are in kW or tons) into volume flow rates (in m3 /s or CFM) for the…
AIR CONDITIONING SYSTEM DESIGN
In designing air conditioning systems, the first challenge is to understand the components that affect the building heat gain or heat loss - this process is called heating or cooling…
Approaches to Humidity Control
Humidity control in a conditioned space is done by controlling the amount of water vapor present in the air in the space. When relative humidity at the desired temperature set-point…
Approaches to Temperature Control
Temperature control in an air conditioning system is achieved by passing the air through the cooling or heating coil, which may use any of the following approaches: 1. Vary the…
AIR CONDITIONING PSYCHROMETRICS
In air-conditioning system, the air must undergo one or several of the following processes: Psychrometrics can be used to predict changes in the environment when the amount of heat and/or…
