Refrigerant: Testing and Inspection

ON-VEHICLE INSPECTION







1. INSPECT REFRIGERANT VOLUME
a. Check the sight glass on liquid tube sub-assembly A.
Test conditions:
- Engine running at 1,500 rpm.
- Blower speed control switch at HI.
- A/C switch ON.
- Temperature control lever in MAX. COLD position.
- All doors fully open.

2. CHECK REFRIGERANT PRESSURE USING MANIFOLD GAUGE SET
a. This is a method to identify trouble areas by using a manifold gauge set. Read the manifold gauge pressure under the following conditions.
Test conditions:
- Engine warm.
- All doors fully open.
- A/C switch ON.
- Blower speed control switch at HI.
- Engine running at 1,500 rpm.
- Air inlet mode damper set at recirculation.
- Temperature control lever in MAX. COLD position.
- Air temperature at air inlet 30 to 35 °C (86 to 95 °F).




1. When the refrigerant volume is correct, the gauge reading indicates as follows:
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)

HINT: Pressure varies in accordance with certain conditions (outside air temperature, sunlight and wind).







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:

3. INSPECT IDLING SPEED
a. Warm up the engine.




b. Inspect the idling speed when these conditions are established.
- Engine warm
- Transmission shifted to either the neutral or the parking position.
If the idling speed is not as specified, check the idle control system.