This unit covers:

Explain the principles of refrigeration.
Describe the four cycles of refrigeration.
Describe the high- and low-pressure sides of an air conditioning system.
Explain the basic function and construction of each major part of a typical heating and air
conditioning system.
Summarize the operation and interaction of heating, ventilation, and air conditioning
systems.
Describe safety precautions to be observed when working on heating and air conditioning
systems.

Visually inspect a heating and air conditioning system and locate obvious troubles.
Diagnose common heating and air conditioning problems.
Describe the functions and uses of air conditioning test equipment.
Locate air conditioning and heating system leaks.
Explain how to replace major heating and air conditioning components.
Describe the general procedures for evacuating and charging an air conditioning system.
Demonstrate safe working practices when servicing heating and air conditioning
equipment.