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Fundamentals of Psychrometrics

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What You Will Learn

You will develop an understanding of the basic concepts of psychrometrics including moist air properties, evaporation, enthalpy, and temperature change, plus the basic HVAC processes. After completing the course, you should know how to: use a psychrometric chart; properly design an HVAC system based on psychrometric principles; conduct a psychrometric analysis of HVAC components such as air handling units, heating and cooling coils,  humidifiers and de humidifiers; evaluate the needs of individual spaces within a building; and determine energy reduction opportunities for HVAC systems.

You will also learn about s few of the special HVAC systems and the psychrometric analysis that is required to understand these systems, plus design suggestions these special systems.

You will be tested at end of each section with Skill Development Exercises so you can truly feel confident about your progress and understanding of the presented material.

Course Content

  • Introduction to Psychrometrics – Understand the concept of temperature change, moisture change, enthalpy and the volumetric airflow equations and calculations.
  • Properties of Moist Air – The nature of air-water mixtures, indicators of moisture concentration in air, plus the 8 properties that we use in psychrometric analysis.
  • Introducing the Psychrometric Chart – How we create the psychrometric chart from the thermodynamic properties of moist air tables and scale for the eight different properties.
  • Air Conditioning Processes on the Psychrometric Chart – We define both sensible and latent heating and cooling plus plot each process on the psychrometric chart.
  • Psychrometric Analysis for HVAC Design – Schematic of an air-conditioning system, mixing air streams, designing with sensible heat ratio for cooling, and introduction of outdoor air for ventilation.
  • Psychrometric in HVAC Equipment – The air handling unit, psychrometrics of cooling and heating coils, humidification equipment, temperature rise due to fans, and designing with the same heating/cooling CFM
  •  Psychrometrics in Zoned HVAC Systems – In depth look at the psychrometrics of all the common constant air volume and common variable air volume systems. Both heating and cooling are explored.
  • Energy Conservation and Psychrometrics – What the psychrometric chart shows about heat recovery, energy recovery, water and airside economizers, and supply air temperature reset.
  • Special Applications and Psychrometric Considerations – An in depth look at airflow through a cooling tower, indoor swimming pool design, Clean room or Clean Space design, and both direct and indirect evaporative cooling applications
  • Appendix tables – Thermodynamic Properties of Moist Air, Unit Conversion Factors, World Climatic Design Information and Thermodynamic Properties of Water at Saturation

Who Should Enroll in this Course?

This course is designed for:

  • Recent engineering graduates who need additional courses in HVAC topics to improve their on-the-job performance.
  • Engineers who have recently entered the HVAC field from other engineering disciplines.
  • Engineers that maybe preparing for the Mechanical PE exam that need a refresher on HVAC and psychrometrics
  • Technicians who want to increase their knowledge and skills of psychrometrics in HVAC.
  • Architects, construction and building management professionals, Industrial owners and others responsible for the performance of HVAC systems

Getting Started:

Self-Directed Learning
$199 ( ASHRAE Member: $150)

Earn 20 PDHs/2.0 CEUs

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