Air Conditioning and Refrigeration Skills

Course 1 – Introduction to Air Conditioning and Refrigeration

Prerequisites: This lesson is designed so that that no prior knowledge is required.

Description: This lesson covers the principles of Air Conditioning and Refrigeration. This course focuses on the factors involved in the refrigeration process, including methods of heat transfer, how substances change phase, and the relationship between pressure and temperature. It also shows the basic components of a refrigeration system and explains their functions.

Objectives:

• Understand the technical definition and applications of refrigeration
• Identify the differences between convection and conduction and the factors that affect each process
• Display an understanding of the terminology used when describing refrigeration theory
• Demonstrate a knowledge of the relationship of pressure and temperature
• Identify the four main components in a refrigeration cycle

Course 2 – AC System Components

Prerequisites: This lesson is designed for participants who are familiar with the principles of refrigeration theory.

Description: This lesson covers vapor compression equipment components. This course focuses on various equipment designs typically used in air conditioning and refrigeration systems. It shows variations in the design of system components including the evaporator, compressor, condenser, and the metering device.

Objectives:

• Identify and understand the operation of the components of an air conditioning or refrigeration system
• Demonstrate a knowledge of the refrigerant circuit
• Understand the differences between shell and tube and tube and fin evaporators
• Understand the differences between shell and tube and tube in tube condensers
• Identify the different types of metering devices used in refrigeration systems

Course 3 – AC Test and Maintenance Equipment

Prerequisites: This lesson is designed for participants who are familiar with the principles of refrigeration theory, the basic operation of air conditioning and refrigeration systems, the proper use of hand tools, and good safety practices.

Description: This lesson covers test and maintenance equipment. This course shows and explains the use of equipment such as temperature sensors, pressure gauges, gauge manifolds, leak detectors, vacuum pumps, and vacuum gauges. It also includes guidelines for the care of each type of equipment.

Objectives:

• Identify and understand the instruments used for checking temperatures at various points in the refrigeration circuit
• Identify and understand the instruments used for checking pressures at various points in the refrigeration circuit
• Understand the operation of leak detectors during a leak detection procedure
• Understand the proper care and maintenance of temperature and pressure sensing instruments

Course 4 – AC Routine Checks and Maintenance

Prerequisites: This lesson is designed for participants who are familiar with the principles of refrigeration theory, the basic operation of air conditioning and refrigeration systems, the use of the appropriate tools and test instruments, the use of the liquid sub-cooling and superheat methods of checking a charge, and the safety practices that should be followed when working on air conditioning and refrigeration systems.

Description: This lesson covers common maintenance procedures performed on air conditioning and refrigeration systems. This program shows and explains the basic steps in a general system check. It also covers common periodic maintenance procedures, including checking for refrigerant leakage, checking for correct refrigerant charge, and checking the oil level in a compressor.

Objectives:

• Demonstrate the proper procedures for checking a refrigerant charge
• Demonstrate the proper procedures for checking the oil levels in a refrigeration system compressor
• Understand the importance of maintenance procedures such as checking pressure levels across components
• Identify the symptoms of a low charge
• Demonstrate the procedures for removing or adding oil to a compressor
• Explain the steps involved in a system startup

Course 5 – Maintaining Refrigerant Levels

Prerequisites: This lesson is designed for participants who are familiar with the principles of refrigeration theory, the basic operation of air conditioning and refrigeration systems, the use of the appropriate tools and test instruments, and the safety practices that should be followed when working on air conditioning and refrigeration systems.

Description: This lesson covers system pump down, evacuation, and charging. This course shows and explains the basic steps involved in pumping a system down, performing a deep vacuum system evacuation, a triple evacuation, high-side charging, and low-side charging. This course also covers basic principles and applications of each of these procedures.

Objectives:

• Describe the pump down procedure used for isolating refrigerant in a certain part of the system
• Explain the purpose of a pump down procedure
• Describe the deep vacuum and triple evacuation methods of system evacuation
• Explain the purpose of a system evacuation and the advantages and disadvantages of each method
• Demonstrate the two methods of charging a refrigeration system
• Explain the circumstances of when each charging method should be used

Course 6 – Troubleshooting Cooling Systems

Prerequisites: This lesson is designed for participants who are familiar with the principles of refrigeration, the function and operation of each component in a refrigeration system, good safety practices, and the tools and equipment used during troubleshooting.

Description: This lesson covers mechanical troubleshooting as applied to a variety of problems. This course focuses on how to troubleshoot short cycling of the compressor, restrictions in the liquid lines and installed accessory devices, insufficient cooling of the refrigeration system, and improper heat transfer. It also shows how to repair a clogged filter drier.

Objectives:

• Demonstrate a full understanding of the troubleshooting process
• Explain the difference between causes and symptoms
• Display an understanding of the operation and basic components of an air conditioning and refrigeration system
• Understand the importance of a correct and stable charge to the refrigeration cycle
• Demonstrate a knowledge of troubleshooting the main components in a refrigeration system

Course 7 – Troubleshooting Heating Systems

Prerequisites: This lesson is designed for participants who are familiar with the principles of refrigeration, the function and operation of each component in a refrigeration system, good safety practices, and the tools and equipment used during troubleshooting and maintaining a chiller.

Description: This lesson covers the basic operation of a boiler-based heating system and the components contained in these systems. This course focuses on troubleshooting the burner, heat exchanger, pumps, relief valves, and the expansion tank.

Objectives:

• Visually identify and describe the function of each basic component hot water or steam boiler
• Understand the basic maintenance procedures to keep a heating system running safely and efficiently
• Explain the difference between co-current and counter-current heat exchangers
• Identify symptoms of a malfunctioning component in a heating system
• Understand the importance of proper water chemistry in a heating system /li>