Testing/Fault Diagnosis

This is a method in which the trouble is located by using a manifold gauge set.
Installation/Removal

Read the manifold gauge pressure when the following conditions are established:
(a) Temperature at the air inlet with the switch set at RECIRC is 30 - 35° C (86 - 95° F)
(b) Engine running at 1,500 rpm
(c) Blower speed control switch set at high
(d) Temperature control set at max. cool

HINT: It should be noted that the gauge indications may vary slightly due to ambient temperature conditions.





1. NORMALLY FUNCTIONING REFRIGERATION SYSTEM
Gauge reading:
Low pressure side:
0.15 - 0.25 MPa (1.5 - 2.5 kgf/sq.cm)
High pressure side:
1.37 - 1.57 MPa (14 - 16 kgf/sq.cm)





2. MOISTURE PRESENT IN REFRIGERATION SYSTEM





3. INSUFFICIENT REFRIGERANT





4. POOR CIRCULATION OF REFRIGERANT





5. REFRIGERANT DOES NOT CIRCULATE





6. REFRIGERANT OVERCHARGE OR INSUFFICIENT COOLING OF CONDENSER





7. AIR PRESENT IN REFRIGERATION SYSTEM





8. EXPANSION VALVE IMPROPERLY MOUNTED/HEAT SENSING TUBE DEFECTIVE (OPENS TOO WIDE)





9. DEFECTIVE COMPRESSION COMPRESSOR