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Refrigerant: Testing and Inspection

ON-VEHICLE INSPECTION

1. INSPECT REFRIGERANT PRESSURE WITH MANIFOLD GAUGE SET




a. This is a method to specify trouble areas by using a manifold gauge set. Read the manifold gauge pressure when the following conditions are established.
Test conditions:
- Engine has been warmed up.
- All doors are fully open.
- A/C switch is ON.
- Engine is running at 1,500 rpm.
- Air inlet mode selector damper is set at recirculation.
- Temperature control switch is in MAX. COLD position.
- Blower speed control switch is in HI position.
- Air temperature at the air inlet is 30 to 35 degrees C (86 to 95 degrees F).




1. When the refrigerant volume is proper.

Gauge reading:
Low pressure side: 0.15 to 0.25 MPa (1.5 to 2.5 kgf/sq.cm)
High pressure side: 1.37 to 1.57 MPa (14 to 16 kgf/sq.cm)




2. When there is moisture in the refrigeration system.




3. When cooling is insufficient.




4. When the circulation of the refrigerant is poor.




5. When the refrigerant does not circulate.







6. When the refrigerant is overcharged or cooling of condenser is insufficient.




7. When there is air in the refrigeration system.




8. When the expansion valve malfunctions.







9. When the compressor is defective.