Refrigerant Pressures

REFRIGERANT

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 °C (86 to 95 °F).




Gauge readings (Reference)




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: