Refrigerant: Testing and Inspection

AIR CONDITIONING: REFRIGERANT: ON-VEHICLE 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°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/cm2)
High pressure side:
1.37 to 1.57 MPa (14 to 16 kgf/cm2)
(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: