A/C Key Components and Functions. To remove heat from the passenger compartment, all major A/C system components must operate at peak efficiency. Each component is dependent upon the function of the others. The spread of contaminants reduces system efficiency and will eventually lock up the compressor or block the flow of the refrigerant-lubricant.

High-Temperature/High-Pressure Gas High-Temperature/High-Pressure Vapor Low-Temperature/Low-Pressure Liquid Low-Temperature/Low-Pressure Gas

Compressor -- Responsible for pumping refrigerant through the air conditioning system and increasing the pressure of incoming refrigerant gases. Located under the hood. Belt driven. Problems with inadequate lubrication inside the compressor are the cause of excessive wear, contamination and the spread of particles throughout the A/C system.
	Manifold -- Connects the suction and discharge lines to the compressor. Metal particles adhering to the internal walls are evidence of system-wide contamination.
Condenser -- Heat exchanger responsible for changing refrigerant from a high-pressure gas state to a high-pressure liquid state through principles of condensation. Located in front of radiator. The small passages inside the condenser are very susceptible to clogging from the particles that enter under high pressure.
	Liquid Line -- Moves the high-pressure liquid through the system. Particles frequently cling to the interior walls and catch other particles as they flow through.
Orifice Tube -- Responsible for regulating refrigerant flow to the evaporator and changing refrigerant pressure from high to low. Located under the hood. The photo (top of page)  comparing a clogged orifice tube to a new one demonstrates the seriousness of the problem caused by system contamination.
	Evaporator -- Responsible for changing state of refrigerant from low-pressure liquid to low-pressure gas through principles of evaporation. Located in the passenger compartment. In all but the most serious instances of system contamination, the evaporator is the one major component that does not need replacement. Any particles that reach the evaporator tend to flow through.
Accumulator -- Responsible for storing excess refrigerant not utilized by evaporator, filtering contaminants out of refrigerant and removing any moisture that is in system. Located under the hood. Due to the concentrations of particles that are trapped here, the accumulator frequently requires replacement.

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