1. Refrigerant Circulation

• Acts as the system's pump to move refrigerant through the A/C loop
• Creates necessary pressure differential between high and low sides
• Maintains continuous flow through condenser, expansion valve, and evaporator

2. Pressure Generation

• Compresses low-pressure gas (35-50 psi) from the evaporator
• Outputs high-pressure gas (150-300 psi) to the condenser
• Enables proper phase change of refrigerant throughout the system

3. Heat Transfer Facilitation

• Increases refrigerant temperature for efficient heat rejection in the condenser
• Creates the pressure drop needed for evaporator cooling effect
• Allows refrigerant to absorb cabin heat effectively

4. System Lubrication Management

• Circulates oil throughout the A/C system
• Maintains proper lubrication of all moving components
• Preserves compressor internal parts and reduces wear

5. Cooling Capacity Control

• Variable displacement models adjust output to match thermal load
• Regulates cooling power through clutch cycling (fixed displacement types)
• Maintains stable evaporator temperatures

Key Performance Characteristics:

• Compression Ratio: Typically 5:1 to 8:1 for automotive applications
• Flow Rate: Usually 100-200 cubic centimeters per revolution
• Efficiency: Measured by volumetric and isentropic efficiency ratings

System Interaction:

• Works with the condenser to reject heat
• Cooperates with the expansion device to create cooling
• Partners with the evaporator to absorb cabin heat
• Interfaces with the accumulator/receiver-drier for refrigerant management

Modern Advancements:

• Variable displacement technology reduces cycling losses
• Internal relief valves prevent overpressure conditions
• Lightweight designs improve fuel efficiency
• Integrated sensors enable smart system control