Lesson 1 - Air Movement and Distribution
Topics:
Air handling system; Comfort, process air conditioning; Heat and moisture transport; How air moves; Types of airflow; Pressure relationships; Controlled ventilation and pressurization; Dual-duct systems; System velocity
Learning Objectives:
– List the variables controlled by an air-handling system.– Define comfort and explain how to predict whether or not people in a space will be comfortable.
– Define the following terms: laminar flow, turbulent flow, streamlining, and eddy currents.
– Differentiate between static pressure, velocity pressure, and total pressure in an air-distribution system.
– Compare a dual-duct system to a single-duct system in both structure and operation.
Lesson 2 - Fans and Fan Motors
Topics:
Fan construction; Centrifugal and axial-flow fans; Fan performance curves; System characteristics; Preventive maintenance for fans; Impeller maintenance; Belt, drive-train, and bearing maintenance
Learning Objectives:
– Describe the two basic types of fans used in air-conditioning systems.– Define the terms system characteristic and point of operation.
– Explain why a knowledge of fan laws and performance curves is necessary when altering an air-handling system.
– Describe preventive-maintenance procedures for typical fans.
– Explain how to replace the bearings in a centrifugal fan.
Lesson 3 - Ductwork Types, Fabrication, and Repair
Topics:
Types of ducts; Duct designations, fittings, and connections; Insulation; Terminal devices; Fabricating sheet metal ducts; Duct reinforcement; Duct maintenance
Learning Objectives:
– Define the term aspect ratio.– Compare and contrast a radial duct system and an extended plenum system.
– Describe the structure and purpose of dampers and turning vanes.
– Identify a variety of fittings and connections used in a sheet metal ductwork system.
– Explain how and why ducts are insulated and reinforced.
– Identify common types of sheet metal seams and describe how each is fashioned.
– Explain the basic servicing and inspection procedures for ductwork systems.
Lesson 4 - Air Filtration
Topics:
Mechanical air filters; Service schedules; Servicing impingement filters; Replacing dry media filters; Installing HEPA filters; Electronic air cleaners
Learning Objectives:
– Explain the function of an air filter.– Describe the two main types of mechanical air filters.
– Explain how to establish a service schedule for air filters.
– Explain how to clean and/or replace the filters in your HVAC system.
– Explain the operation of electronic air cleaners and tell how they are serviced.
Lesson 5 - Air System Balancing and Troubleshooting
Topics:
Measuring instruments; Pretest data collection; Preparing the system; Measuring and adjusting the main airflow, branch ducts, registers, and diffusers; Troubleshooting
Learning Objectives:
– Explain why air-handling systems need to be balanced.– Describe the instruments used to test and balance an air-handling system.
– Demonstrate how to measure velocity pressure and show how airflow rates are calculated from these pressure readings.
– Describe a pitot-tube traverse.
– Explain in step-by-step fashion how to test and balance an air-handling system.
– Name common complaints related to air-handling systems and give common causes.
Lesson 6 - Indoor Air Quality and Sick Building Syndrome
Topics:
Sick building syndrome (SBS) characteristics, contributors; HVAC systems as contaminant sources; Pollutant pathways; Odors and contamination, Building-related illness
Learning Objectives:
– Discuss the characteristics of sick building syndrome (SBS).– Describe the process for investigating an SBS complaint and explain how to conduct a facility site review.
– Discuss ways a facility can minimize the probability of perceived SBS problems.
– Discuss internal and external SBS contributors, including HVAC systems, and discuss ways to eliminate or reduce the problems.
– Describe specific ways to control particulates, odors, and other contaminants.
– Define the abbreviations SBS, IAQ, BRI, VOC, and MCS.
